Climate Neutral and Resilient Farming Systems: Practical Solutions for Climate Mitigation and Adaptation

Nagothu, Udaya Sekhar (Ed.) Book Climate Neutral and Resilient Farming Systems: Practical Solutions for Climate Mitigation and Adaptation Earthscan Food and Agriculture Provided in Cooperation with: Taylor & Francis Group Suggested Citation: Nagothu, Udaya Sekhar (Ed.) (2023) : Climate Neutral and Resilient Farming Systems: Practical Solutions for Climate Mitigation and Adaptation, Earthscan Food and Agriculture, ISBN 9781000776225, Routledge, London, https://doi.org/10.4324/9781003273172 This Version is available at: https://hdl.handle.net/10419/281308 Standard-Nutzungsbedingungen: Die Dokumente auf EconStor dürfen zu eigenen wissenschaftlichen Zwecken und zum Privatgebrauch gespeichert und kopiert werden. Sie dürfen die Dokumente nicht für öffentliche oder kommerzielle Zwecke vervielfältigen, öffentlich ausstellen, öffentlich zugänglich machen, vertreiben oder anderweitig nutzen. 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If the documents have been made available under an Open Content Licence (especially Creative Commons Licences), you may exercise further usage rights as specified in the indicated licence. https://creativecommons.org/licenses/by-nc-nd/4.0/ “ This book makes a timely contribution towards understanding the relevance and practicality of climate neutral and resilient farming systems with focus on smallholder farms, and the potential for climate mitigation and the Nationally Determined Contributions ( NDCs). It adds new knowledge and is useful for a wide audience in this field.” Dr. V. Geethalakshmi, Ph.D., FAAM, ViceChancellor, Tamil Nadu Agricultural University, Coimbatore, India “IPCC’s 6th Assessment Report of Working Group I stated in 2021 that ‘It is unequivocal that human influence has warmed the atmosphere, ocean and land’. The agricultural sector should take immediate measures to mitigate and adapt to the climate change due to global warming. For irrigation engineers, it is very significant to have a firm grasp of the topic Climate Neutral and Resilience Farming Systems (CNRFSs), which is the focus of this book.” Tsugihiro Watanabe, Vice President of the International Commission on Irrigation and Drainage ( ICID), Professor Emeritus of Kyoto University, Japan “ This book is very timely and a valuable knowledge contribution on managing greenhousegas emissions in the agriculture sector. Each chapter underscores low carbon emission agriculture in achieving the 1.5°C target of the Paris Agreement. An insightful publication!” Paxina ChilesheToe, Regional Climate and Environment Specialist, Environment, Climate, Gender and Social Inclusion Division, Strategy and Knowledge Department, IFAD, Nairobi, Kenya “ We need to deploy innovative solutions at scale to tackle climate change. This book is timely in helping to promote agrifood systems as an important part of the solution to the climate crisis, especially in the lead up to COP27 in Egypt and beyond.” Zitouni OuldDada, Deputy Director, Office of Climate Change, Biodiversity and Environment ( OCB), Food and Agriculture Organization of the United Nations ( FAO), Via delle Terme di Caracalla, Rome, Italy Climate Neutral and Resilient Farming Systems This book presents evidencebased research on climateneutral and resilient farming systems and further provides innovative and practical solutions for reducing greenhouse gas emissions and mitigating the impact of climate change. Intensive farming systems are a significant source of greenhouse gas emissions, thereby contributing to global warming and the acceleration of climate change. As paddy rice farming is one of the largest contributors, and environmentally damaging farming systems, it will be a particular focus of this book. The mitigation of greenhouse gas emissions needs to be urgently addressed to achieve the 2°C target adopted by COP21 and the 2015 Paris Agreement, but this is not possible if local and national level innovations are not accompanied by international level cooperation, mutual learning and sharing of knowledge and technologies. This book, therefore, brings together international collaborative research experiences on climateneutral and resilient farming systems compiled by leading scientists and experts from Europe, Asia and Africa. The chapters present evidencebased research and innovative solutions that can be applied or upscaled in different farming systems and regions across the world. Chapters also present models and technologies that can be used for practical implementation at the systemic level and advance the state of the art knowledge on carbonneutral farming. Combining theory and practice, this interdisciplinary book provides guidance which can inform and increase cooperation between researchers from various countries on climateneutral and resilient farming systems. Most importantly, the volume provides recommendations which can be put into practice by those working in the agricultural industry, especially in developing countries, where they are attempting to promote climateneutral and resilient farming systems. The book will be of great interest to students and academics of sustainable agriculture, food security, climate mitigation and sustainable development, in addition to policymakers and practitioners working in these areas. Udaya Sekhar Nagothu is Research Professor and Director at the Centre for International Development, NIBIO ( Norsk Institutt for Biookonomi/ Norwegian Institute of Bioeconomy Research), Norway. He is the editor of The Bioeconomy Approach ( 2020), Agricultural Development and Sustainable Intensification ( 2018), Climate Change and Agricultural Development ( 2016) and Food Security and Development ( 2015). Earthscan Food and Agriculture Farming with the Environment Thirty Years of Allerton Project Research Chris Stoate Net Zero, Food and Farming Climate Change and the UK AgriFood System Neil Ward Conservation Agriculture in India A Paradigm Shift for Sustainable Production Edited by A.R. Sharma Agricultural Commercialization, Gender Equality and the Right to Food Insights from Ghana and Cambodia Edited by Joanna Bourke Martignoni, Christophe Gironde, Christophe Golay, Elisabeth Prügl and Dzodzi Tsikata The Sociology of Farming Concepts and Methods Jan Douwe van der Ploeg Genetically Modified Crops and Food Security Commercial, Ethical and Health Considerations Edited by Jasmeet Kour, Vishal Sharma and Imtiyaz Khanday Climate Neutral and Resilient Farming Systems Practical Solutions for Climate Mitigation and Adaptation Edited by Udaya Sekhar Nagothu For more information about this series, please visit: www.routledge.com/ books/ series/ ECEFA/ Climate Neutral and Resilient Farming Systems Practical Solutions for Climate Mitigation and Adaptation LONDON AND NEW YORK Edited by Udaya Sekhar Nagothu First published 2023 by Routledge 4 Park Square, Milton Park, Abingdon, Oxon OX14 4RN and by Routledge 605 Third Avenue, New York, NY 10158 Routledge is an imprint of the Taylor& Francis Group, an informa business © 2023 selection and editorial matter, Udaya Sekhar Nagothu; individual chapters, the contributors The right of Udaya Sekhar Nagothu to be identified as the author of the editorial material, and of the authors for their individual chapters, has been asserted in accordance with sections 77 and 78 of the Copyright, Designs and Patents Act 1988. The Open Access version of this book, available at www.taylorfrancis. com, has been made available under a Creative Commons AttributionNon CommercialNo Derivatives 4.0 license. Trademark notice: Product or corporate names may be trademarks or registered trademarks, and are used only for identification and explanation without intent to infringe. British Library CataloguinginPublication Data A catalogue record for this book is available from the British Library Library of Congress CataloginginPublication Data Names: Nagothu, Udaya Sekhar, editor. Title: Climate neutral and resilient farming systems : practical solutions for climate mitigation and adaption / edited by Udaya Sekhar Nagothu. Description: New York, NY : Routledge, 2023. | Includes bibliographical references and index. Identifiers: LCCN 2022021933 (print) | LCCN 2022021934 (ebook) Subjects: LCSH: Sustainable agriculture. | Crops and climate. | Agriculture—Environmental aspects. Classification: LCC S600.5 .C556 2023 (print) | LCC S600.5 (ebook) | DDC 630—dc23/eng/20220722 LC record available at https://lccn.loc.gov/2022021933 LC ebook record available at https://lccn.loc.gov/2022021934 ISBN: 9781032225791 ( hbk) ISBN: 9781032225845 ( pbk) ISBN: 9781003273172 ( ebk) DOI: 10.4324/ 9781003273172 Typeset in Goudy by codeMantra Contents Preface ix List of figures xi List of tables xv List of boxes xvii List of contributors xix 1 Climate change impacts on agriculture: Challenges and options to reduce emissions through climateneutral and resilient farming systems 1 UDAYA SEKHAR NAGOTHU, ANDREW BORRELL, AND MEHRETEAB TESFAI 2 Precisionbased soil and nutrient management tools for enhancing soil health while reducing environmental footprint 24 AMARESH KUMAR NAYAK, SANGITA MOHANTY, MEHRETEAB TESFAI, RAHUL TRIPATHI, ANJANI KUMAR, AND UDAYA SEKHAR NAGOTHU 3 Organizational alternate wetting and drying ( AWD) irrigation management in rice by water user groups for reducing methane emission and water saving 45 KIMIHITO NAKAMURA, LE XUAN QUANG, AND SOKEN MATSUDA 4 Integrated pest management in rice and the potential to contribute to climateneutral and resilient farming systems 69 SHYAMARANJAN DAS MOHAPATRA, NAJAM WARIS ZAIDI, MINATI MOHAPATRA, UDAYA SEKHAR NAGOTHU, RADHAKRUSHNA SENAPATI, MUNMUN MOHAPATRA, BHUBANANDA ADHIKARI, SUBHENDU SEKHAR PRADHAN, AND AMARESH KUMAR NAYAK Tables 2.1 Basic principles of precisionbased tools/ techniques for N management 28 2.2 Performance of LCCbased N application compared to blanket N application 30 2.3 Examples of previous research findings using SSNM approaches 35 5.1 Greenhouse gas ( GHG) emission ( tCO2eq/ ha) from SRI and conventional fields 97 6.1 Main advantages and disadvantages of DSR compared to transplanted puddled rice ( TPR) 108 6.2 Desirable traits of rice cultivars suitable for DSR 110 6.3 Effect of greenhouse gas emissions, GWP on different crop establishment techniques 116 6.4 Examples of research findings related to effective weed control measures in DSR 119 7.1 Potential GHG savings from various measures in practice to reduce EU agriculture and land use emissions 132 7.2 Rice farms analysed for carbon footprint evaluation 135 7.3 List of innovative agricultural practices applied in the subgroup of rice farms 136 8.1 Potential AE contributions to relevant SDGs and specific targets along with references 149 8.2 The ten elements of AE ( FAO, 2019) and their implications when put in practice 150 8.3 Summary of the general characteristics of the study sites in eastern Zambia 154 8.4 Average grain yields of maize, groundnut, and soybean by treatment ( n = 15 demo plots) 157 8.5 Nutritional and antinutritional properties of maize by treatment ( n = 37) 158 8.6 Nutritional and antinutritional properties of soybean by treatment ( n = 26) 159 8.7 Nutritional and antinutritional properties of groundnut by treatment ( n = 25) 159 xvi Tables 8.8 Matching the AE practices/ approaches implemented in the case study sites with the most appropriate AE elements/ principles 160 9.1 Ecological, nutritional, and socioeconomic benefits provided by Brachiaria forage 174 9.2 Socioeconomic and physical characteristics of farmers in Kangundo ( n = 316) 177 9.3 Household socioeconomic and physical characteristics in Nyamagabe ( 308 HHs) 182 10.1 A list of farming systems to reduce GHGs, and improve resilience to climate change 199 Boxes 2.1 4R Nutrient Stewardship principle 26 2.2 Green Seeker: Principles and Applications 34 6.1 Nutrient management recommendations for dryDSR under different agroecological settings 113 8.1 Components of sustainable intensification 152 Contributors Bhubananda Adhikari is Research Scholar at Odisha University of Agriculture& Technology, Bhubaneswar, India. Laura Bardiis Director of Research at the Research Centre for Engineering and AgroFood Processing, Council for Agricultural Research and Economics ( CREA), Italy. Chiara Bertora is agroecologist and former researcher in the Department of Agricultural, Forest and Food Sciences ( DISAFA), University of Turin, Italy. Patrizia Borsottois Researcher at the Research Centre for Agricultural Policies and Bioeconomy of the Council for Agricultural Research and Economics ( CREA), Italy. Andrew Borrellis Professor at Queensland Alliance for Agriculture and Food Innovation ( QAAFI), Hermitage Research Facility, University of Queensland, Warwick, Australia. Giacomo Brancais Associate Professor in the Department of Economics, Engineering, Society and Business, Tuscia University, Italy. Luca Cacchiarelliis Researcher in the Department of Economics, Engineering, Society and Business, Tuscia University, Italy. Roberto Cagliero is Researcher at the Research Centre for Agricultural Policies and Bioeconomy of the Council for Agricultural Research and Economics ( CREA), Italy. Alamu Oladeji Emmanuelis Food Scientist working at the International Institute for Tropical Agriculture ( IITA), Zambia office. Omedé Gabrieleis Research Fellow in the Department of Agricultural, Forest and Food Sciences ( DISAFA), University of Turin, Italy. Jan Willem Ketelaaris Chief Technical Advisor of the FAO Regional Integrated Pest Management/ Pesticide Risk Reduction Programme at FAO’s Regional Office for Asia and Pacific, Bangkok. xx Contributors Anjani Kumaris Senior Scientist in the Division of Crop Production, National Rice Research Institute ( ICAR), Cuttack, India. Maite MartínezEixarchis Researcher at the Institute of Agrifood Research and Technology ( IRTA), Continental and Marine Waters, Spain. Abha Mishra is Director of ACISAI Center Asian Institute of Technology, Khlong Luang, Thailand. Soken Matsudais Researcher at National Agriculture and Food Research Organization ( NARO), Japan. Sangita Mohantyis Senior Scientist in the Division of Crop Production, National Rice Research Institute ( ICAR), Cuttack, India. Shyamaranjan Das Mohapatrais Principal Scientist in the Division of Crop Protection, National Rice Research Institute ( ICAR), Cuttack, India. Kiran Mohapatra is Research Scholar in the Division of Crop Production, National Rice Research Institute ( ICAR), Cuttack, India. Minati Mohapatrais Assistant Research Engineer at Odisha University of Agriculture& Technology, Bhubaneswar, India. Munmun Mohapatrais Research Scholar at Odisha University of Agriculture& Technology, Bhubaneswar, India. Stefano Monacois Researcher at the Research Centre for Engineering and AgroFood Processing, Council for Agricultural Research and Economics ( CREA), Italy. Udaya Sekhar Nagothuis Research Professor and Director of Centre for International Development, Norwegian Institute of Bioeconomy Research, Ås, Norway. Kimihito Nakamurais Professor of Hydrological Environment Engineering in the Graduate School of Agriculture, Kyoto University, Japan. Amaresh Kumar Nayakis Principal Scientist and Head Division of Crop Production at National Rice Research Institute, Cuttack, India. Joel Ngumayois Senior M&E Specialist/ Researcher at Community Markets for Conservation ( COMACO), Lusaka, Zambia. Joyce Bakuwa Njolomais Associate Scientist– Systems at World Agroforestry, Malawi and Associate Professor at the Lilongwe University of Agriculture and Natural Resources ( LUANAR), Lilongwe, Malawi. Chiara Perelliis Junior Researcher in the Department of Economics, Engineering, Society and Business, Tuscia University, Italy. Subhendu Sekhar Pradhanis Computer Assistant in the Division of Crop Protection, National Rice Research Institute ( ICAR), Cuttack, India. Contributors xxi Le Xuan Quang is Associate Professor and Vice Director at the Institute for Water and Environment, Vietnam Academy for Water Resources, Vietnam. Radhakrushna Senapatiis Senior Research Fellow in the Division of Crop Protection, National Rice Research Institute ( ICAR), Cuttack, India. Mehreteab Tesfaiis Senior Researcher at the Norwegian Institute of Bioeconomy Research, Ås, Norway. Rahul Tripathiis Senior Scientist in the Division of Crop Production, National Rice Research Institute ( ICAR), Cuttack, India. Max Whitten is Adjunct Professor in the School of Biological Sciences, The University of Queensland, Brisbane, Australia. Najam Waris Zaidiis Senior Associate Scientist II at International Rice Research Institute, New Delhi, India. DOI: 10.4324/9781003273172-1 Introduction A global climate crisis is drawing the attention of activists, politicians, scientists, and the general public at large, not only due to the increasing rate of extreme climate events across the world and the severity of the destruction caused by these events to communities and ecosystems but also due to their continuous coverage in the media ( WMO, 2021). At the same time, climate change debate is shaping the political landscape in several countries, with some countries seriously concerned and pressing for immediate action, while others do not see it as an immediate threat, even in the developed world. Lack of adequate information, evidencebased data, and uncertainty in forecasts are helping sceptics and politicians in both developed and developing countries to argue that climate change is not an immediate threat to global society. Such ignorance leads to shortsighted policy decisions and lack of needed transformative action and support for investments to combat climate crises. Since 1990, six assessment reports by the Intergovernmental Panel on Climate Change ( IPCC) were prepared, and recommendations were made for cutting down greenhouse gas ( GHG) emissions ( IPCC, 2021). Unfortunately, some world leaders do not recognize the seriousness of the threats and fail to stand by the commitments made to reduce emissions. As long as these commitments are not put into action, it will not be possible to limit global temperature rise to 1.5°C by the end of the century. The IPCC on the Sixth Assessment Report ( AR6) states that “ it is unequivocal that human influence has warmed the atmosphere, ocean and land” and that “ widespread and rapid changes in the atmosphere, ocean, cryosphere and biosphere have occurred” ( IPCC, 2021a). According to the Report, the world has rapidly warmed by 1.1°C which is higher than preindustrial levels, and is now moving towards 1.5° C– a critical threshold level that world leaders agreed to maintain and take measures to prevent warming above that level ( IPCC, 2021b). The complex shifts observed in recent years affecting our planet’s weather and climate systems are contributing to the melting of glaciers, sealevel rise, and 1 Climate change impacts on agriculture Challenges and options to reduce emissions through climateneutral and resilient farming systems Udaya Sekhar Nagothu, Andrew Borrell, and Mehreteab Tesfai 8 Udaya Sekhar Nagothu et al. companies can often account for significant proportions of their total GHG footprint ( Leahy etal., 2020). For example, 57% of Danone’s “ scope 3” GHG emissions are related to the purchase of agricultural products such as milk ( Danone, 2017). Many international food and beverage companies ( e.g. Danone, Mars Inc., Nestle, Tesco, CocaCola Co., Kellogg, PepsiCo., Unilever PLC) are driving climate goals ( Leahy etal., 2020). These companies are setting ambitious emissions targets and increasingly mandating that their suppliers also provide a product that meets the company’s stated climate agenda. Considering the extent of emissions from livestock industries, it is critical that industries actively drive the adoption of climatesmart policies and invest significantly. Total GHG emissions from livestock supply chains alone are estimated to be around 7.1 Gt CO2eq/ yr ( Gerber etal., 2013). The GHG emissions of 35 of the world’s largest meat and dairy companies are reported to account for up to 1 Gt CO2eq/ yr ( 14%). The onfarm supply chains from these companies are a major source of emissions ( GRAIN and the Institute for Agriculture and Trade Policy, 2018). It is likely that these company goals, coupled with global market dynamics, will increasingly shape production systems of the future. While this approach may influence internationally traded products, it may have limited impact on subsistence and smallholder farmers that provide more than half of total food production in many developing countries ( Rapsomanikis, 2015). Investment, development, commercialization, and scaling of nexthorizon technologies should greatly accelerate efforts to reduce GHG emissions in the agriculture sector. There are a range of promising technologies at various stages of development that could have significant GHG abatement potential in the crop and livestock sectors. These include gene editing for disease resistance or for enhanced carbon sequestration, plant and soil microbiome technology, aerobic rice, direct methane capture from beef and dairy cattle, perennial row crops, inhibition of enteric fermentation through vaccines, and novel feed additives ( AlAzzawi, 2021, IGI, 2021; ITIF, 2020; McKinsey& Company, 2020). Policy solutions To achieve any given level of mitigation in GHG emissions at minimum economic cost, two requirements are necessary for policy measures ( OECD, 2021). The first requirement is the use of marketbased policy instruments that achieve a common price for GHG emissions ( such as an emissions tax or emissions trading scheme). The second is that coverage of the marketbased policy includes the largest possible share of global emissions from all regions and sectors. These two policy requirements should ensure that the lowest cost mitigation measures are adopted, given the large heterogeneity in marginal abatement costs among agents, sectors, and regions. So far, no single country has set a mandatory carbon price for agricultural emissions and current evidence suggests considerable reluctance to applying other Climate change impacts on agriculture 9 climate policies with comparable stringency to agriculture ( Leahy etal., 2020). A recent review on agricultural GHG mitigation pathways stated that a more realistic view is needed if we are to avoid modelled emission scenarios providing an overly optimistic picture of mitigation potentials from the agricultural sector ( Leahy etal., 2020). While there are entry points for mitigation of agricultural GHGs outside government price policies, many questions remain unanswered around their efficacy and scalability, requiring a concerted effort to bridge the gap from modelled emissions to realistic policy pathways. Integrated policy interventions that span supply and demand approaches will be required to achieve agricultural mitigation pathways that are aligned with the 1.5ºC pathway ( IPCC, 2019). Agricultural trade is subject to a wide range of constraints and distortionary subsidies that reflect powerful special interests. Furthermore, developing countries’ desire for food selfsufficiency and protection from food price spikes must be considered. It is worth noting that some of these spikes have been linked to increased biofuel demand driven by climate policies in the energy sector of developed countries ( Anderson, 2016). Hence, international coordination is fundamental to addressing concerns about competitiveness, ensuring environmentally effective outcomes, and avoiding negative consequences at the transnational scale ( Blandford and Hassapoyannes, 2018). Current evidence suggests reluctance to apply rigorous climate policies to agriculture, even in developed countries. In theory, substantial reductions in agricultural emissions could be attained through a number of mechanisms, including the widespread introduction of pricebased policies or other measures with an implicit price ( Leahy etal., 2020). However, there appears to be little current interest in such strategies. For example, New Zealand is the only country actively considering a compulsory price on agricultural emissions, although more than 100 countries have included agriculture mitigation in their NDCs ( Richards, 2019). Global versus local scales The global desire to reduce GHG emissions in agriculture is currently weak and needs to be strengthened or the lack of progress will stifle efforts to meet the goals of the Paris Agreement to limit global warming to 1.5°C or well below 2°C ( OECD, 2021). Only 38% of agriculture emissions are covered by nationally determined commitments under the Paris Agreement ( Hönle etal., 2019). This shows that governments are not prioritizing actions to cut emissions and combat climate change. However, policy solutions do exist, despite the reality of barriers to policy implementation. Solutions include choosing policy options that can navigate tradeoffs in economic impacts between different interest groups. Other options could address the practical challenges and transaction costs related to measuring, reporting, and verifying the extent of reductions in GHG emissions. To achieve a 1.5°C pathway, 6– 8 Gt of carbon dioxide sequestration is required. If all of this was to be delivered through forestry, it would require reforesting 50– 60% of the total area that has been deforested over the past 150 years. 10 Udaya Sekhar Nagothu et al. However, there are other options for enhancing soil carbon through regenerative agricultural practices such as lowand notill agriculture, green manuring, composting, cover crops or crop rotations, and legumes sown in pastures ( Raphaela, 2016). Developed versus developing countries It is estimated that smallholder farming contributes about 1.7 Gt CO2eq/ yr emissions ( Vermeulen and Wollenberg, 2017). Given the concerns about food security, selfsufficiency, food sovereignty, and rural poverty, most developing countries will find pricebased policies or stringent regulatory policies targeting agricultural GHG emissions even harder to implement than developed countries ( IPCC, 2019). Therefore, implementation of policies to reduce GHG emissions from the agriculture sector is highly challenging for both developed and developing countries, although there are different constraints, depending on the context. Modelling studies support this view ( Hasegawa etal., 2018), concluding that climate change mitigation actions could have potentially adverse side effects on food security for some populations. More nuanced implementation and targeted support mechanisms for vulnerable groups could overcome many of the negative consequences arising from blunt pricebased policies ( Fujimori etal., 2018; Loboguerrero etal., 2019). However, the question remains as to whether finance, governance, and institutional capacity exist, together with the political will, to deliver policy arrangements of such complexity at the necessary scales required ( Grewer etal., 2018). Climate action and sustainable development goals The sustainable development goal ( SDG) 13 is about climate action and it is one of the United Nations 17 SDGs ( United Nations, 2020). The SDGs provide economic and political legitimacy to introduce sustainable initiatives. Addressing climate action must be seen as an opportunity by countries and not merely an obligation. At the same time, climate action will address other SDGs and, in the process, support global consensus and fulfil national commitments to sustainably manage the Earth’s resources. Countries rebuilding economies after COVID19 should seize this occasion to include green solutions or green growth strategies that can also address climate change. If carefully planned and implemented, actions could simultaneously address SDG 1 ( No poverty), SDG 2 ( Zero Hunger), and SDG 13. A good example could be to introduce directseeded rice ( DSR) to reduce methane emissions in areas where transplanted paddy rice is a dominant system, without compromising on productivity. In dry DSR systems with a different water regime, and less anaerobic conditions, methane emissions could be substantially reduced compared to transplanted paddy rice, due to lower CH4 production and release ( Li etal., 2019). Thus, smallholder rice farmers practising DSR will be able to realize good yields ( SDG 2) and, at the Climate change impacts on agriculture 11 same time, contribute to methane reductions from rice fields ( SDG 13). A sustainable food system incorporating improvements at all levels of the value chain from production to consumption, in other words a green transition from farm to fork, is the way forward. Implementation of the commitments made in the Paris Agreement to combat the climate crisis is essential for the achievement of the SDGs. Innovative and systemic solutions: climateneutral and resilient farming systems Given the huge challenges facing farming systems in general ( soil and water pollution and degradation, biodiversity decline, emerging pests and diseases, GHG emissions, etc.) and conventional systems such as transplanted paddy rice ( low water and nutrient use efficiency, high GHG emissions), as well as other unforeseen shocks and risks, there is an increasing need for systematically identifying, demonstrating, implementing, and assessing/ evaluating innovative solutions that are sustainable and reduce GHGs. Need for assessing current systems and developing appropriate CNRFS A transition to sustainable CNRFS can be achieved, first, by obtaining a better understanding of current systems, including their strengths and weaknesses at field/ landscape scale, their dynamics, interdependencies, local knowledge, drivers and barriers, as well as existing resources and institutions. Adopting a systems approach is the way to better understand and synthesize the complexity of existing farming systems in particular regions in a stepwise manner by: ( i) analysing the problems, root causes, opportunities to improvements; ( ii) examining technological, social/ policy, and economic factors ( e.g. market constraints and consumer’s preferences to assess the opportunities and the willingness to pay for the products); and ( iii) developing pathways to transform the existing value chains towards more economically, socially, and environmentally sustainable ones. At the same time, attention must be paid to environmental conditions including functional agribiodiversity and provision of ecosystem services, damage due to pests, diseases and resilience against weather extremes. In order to ensure farmer adoption of CNRFS, it will be necessary to consider the farm household resourceuse patterns for onfarm and offfarm activities, the cooperation along agrofood value chains, the embeddedness of farming systems and practices in agroecological settings, economic opportunities ( and limitations), institutional context, and cultural values. The related data should ensure that interdependencies, dynamics, and farmer or local knowledge, as well as existing resources and institutions, are duly considered while designing CNRFS. The participatory diagnosis and coanalysis of given farming systems should include quantitative and qualitative methodologies and tools. The analysis must make use of and combine concepts and approaches from the natural sciences 12 Udaya Sekhar Nagothu et al. and social sciences, including quantitative metaanalyses of available data. Good baseline data and indicators derived from the analysis would be necessary for measuring and monitoring progress observed with the introduction of CNRFS. Codesigning and promoting CNRFS After taking inputs from the initial assessment of current systems, the next step should be codesigning combinations of the most effective solutions that are suitable for particular agroecological settings that can lead to improvements ( Dainese etal., 2019). An important advancement would involve combining naturebased and technologybased solutions supported by the right institutional and policybased approaches. Such a combination, where simple and easy to adopt localand naturebased solutions in many settings could, in fact, help in carbon assimilation, as well as reducing GHGs ( EEA, 2021). Emerging evidence indicates that managing whole landscapes has tremendous potential for translational changes in sustainability and CNRFS ( Martin etal., 2019). Landscape factors that promote the richness and abundance of functional groups, such as natural enemies and pollinators, enhance the provision of multiple ecosystem services and contribute to crop yield quantity and quality ( Martin etal., 2019, Dainese etal., 2019). First, one must prioritize to upscale proven local solutions. Second, the aim should be to combine upscaling of local solutions with management of landscapes. These include ( i) the restoration of green infrastructure, i.e. perennial nearnatural or seminatural habitats that act as sources for beneficial organisms such as crop pollinators and arthropod and vertebrate predators of pest insects ( Beddington etal., 2002), and ( ii) the management of crop diversity. Both factors have been shown to improve natural pest control ( Martin etal., 2019). The CNRFS chosen should be sustainable in environmental terms ( in particular contributing to CNRFS), in economic terms ( e.g. relatively low cost and costefficient, contribute to farmer income), and in social terms ( e.g. fostering diverse diets, minimizing health risks, appropriate to the particular sociocultural context). Only if farmers and agrifood chain actors and stakeholders can gain from the new CNRFS will they be motivated to actually adopt and use the solutions? The sustainable solutions need to address the needs in the preproduction phase ( inputs: seeds, nutrients, water, crop and livestock management), as well as in the postproduction phase ( outputs: grains, bioresidues, storage), and market preferences ( e.g. consumer choices, increasing demand for healthy diets). However, for successful adoption and upscaling, the innovative systemic solutions require enabling institutions and policy support ( Nagothu, 2015). The systemic context shaping farmer’s/ stakeholder’s ability to implement these solutions is depicted in Figure1.1, where a transition from the current system towards CNRFS involves interventions at different levels. In order to design promising CNRFS pathways that are appropriate to the different agroecological zones, particular attention should be paid to replacing external farm inputs ( i.e. fertilizers, pesticides) with internal farm inputs ( i.e. Climate change impacts on agriculture 13 naturebased solution such as biopesticides/ biocontrol, biological solutions, improved soil services, conservation agriculture, organic farming). The key would be to increase both sustainability and resilience against future climate stresses and extremes. Examples of improved management practices that will be further discussed in subsequent chapters include the following: • Soil/ nutrient management using soil metagenomics: An important area, which has the potential for GHG reduction if precise management is applied. This can be enhanced by innovative information and communication tools/ sensors/ mobile apps for upscaling and improving precision use of farm inputs ( Chapter2). • Water management: Improving water use efficiency/ water productivity ( e.g. alternate wetting and drying/ drip irrigation, conservation agriculture) that can significantly reduce GHGs ( Chapter3). • Integrated pest, weed, disease management: Using naturebased solutions, e.g. through enhanced farm and landscape functional diversity, integrating physical and other nonchemical measures to manage pests and diseases ( Chapter4). • Crop management: Improving efficiency through systems such as climate resilient rice systems/ agroecological farming practices, short duration flood and drought tolerant crop varieties and cover/ catch crops. Here it is also important to consider specific genetic solutions for adaptation to a particular environment or climate while developing the new crop management practices ( Chapters 5– 8). Existing conditions increasing GHGsemissions, loss of Carbon SOIL:Unbalanced & excessuse of fertilizers WATER: Inefficientwater management CROP: Laqckofintegratedsystems,Puddled paddyricecultivation,chemicalpestcontrol, burningcropresidues MARKETS: Lack of market accessand consumers CNRFSs reducing GHG emissions, increasing C storage SOIL:Precisionsoil/fertilizer management (e.g., soil metagenomics,N-inhibitors) WATER: Wateruse efficiency andimprovement pathways (efficientirrigationand cropping systems) CROP:Integrated anddiversecroppingsystems, Alternate climateneutral cereal-legume, croplivestocksystems MARKETS: Favourable marketsand consumer supportfor greenerproducts Enablinginstitutions &policiestofostertransitionto climateneutral and resilientfarming systems CH4N2OCH4N2OCO2 CO2 Business as UsualCarbon neutral&resilient farmingsystems farms Transition to CNRFSs Figure1.1 Conceptual diagram showing pathways leading towards CNRFS. Source: Authors’ own design. 14 Udaya Sekhar Nagothu et al. • Postharvest, processing, marketing/ distribution to consumption: Key questions relate to consumer preferences, the sharing of higher production costs along the value chain ( including the shares that consumers are willing to cover), addressing fluctuations in market prices and feedback mechanisms on products and production systems ( Chapter9). Irrespective of farm size, ecologically sound practices ( e.g. minimum tillage, legume Nfixing crops, stubble retention) that can reduce environmental impacts, thereby enhancing climate neutrality and keeping food production systems in safe spaces, should be introduced ( Bommarco etal., 2013, Dainese etal., 2019). Further, combining local measures with landscape management concepts ( through permanent green infrastructure, enhanced crop diversity, and coordinated placement of agrienvironment schemes) provides a novel pathway to more sustainable agriculture ( Martin etal., 2019). Digital and spacebased technologies represent another line of promising and emerging solutions to counter environmental costs of crop production systems, improve efficiency, and enhance climate resilience ( King, 2017). Such solutions include precision farming with thresholdbased and spatially targeted application of pesticides and fertilizers, more efficient irrigation systems, and sensorand remote sensingbased monitoring of crop growth and potential risks ( King, 2017). A key factor to bridge gaps between scientific theoretical knowledge and practical implementation is the continuous involvement, training, and codesign of solutions with farmer’s communities and other stakeholders ( Kleijn etal., 2019). Combining the natureand technologybased components to pilot and upscale systematically designed innovative solutions will be the way forward in the future. Thus, it should be possible to overcome the limitations and risks of current conventional farming systems, including stagnation of yields, increasing yield losses due to pests and extreme weather events, degradation of soils, and emission of GHGs. Institutional changes involve a whole range of factors such as implementation of conducive policies, enabling environments and effective value chains ( Glover etal., 2019). Also the influence of risk and uncertainty in relation to socioeconomic and marketing constraints will be important to include while implementing new systems ( Reardon etal., 2019). The diffusion of CNRFS will depend on the role of service providers ( e.g. business, advisory, information, extension) to a large extent. The transformation process should adopt a wider stakeholder perspective in order to come up with strategies for fostering collaboration among actors and enhancing uptake of innovations ( FAO, 2014). The overall aim is to reach netzero emissions, together with reduced external inputs and more stable yields that can contribute to sustainability along agrifood chains. An important step in the process is to address the economic, social, and environmental sustainability challenges related to current farming systems and develop measurable baseline indicators, some of which have already been addressed in the previous stages. Attention is needed to reduce GHG emission in the process. Climate change impacts on agriculture 15 Multiactor partnerships to enhance CNRFS An inclusive multiactor approach aims at a more demanddriven innovation process through the genuine involvement of diverse actors all along the project and different segments of the agrifood chains, from farm to fork. Multiactor platforms ( MAPs) have the potential to bring diverse actors together in a structured process of interactive learning, sharing, empowerment, and collaborative governance ( Brouwer etal., 2015). Together, the actors can discuss opportunities and the ways to achieve a desired set of goals. The MAPs can promote innovation in the face of complexity, uncertainty and risk, and strengthen sciencepolicy linkage. This is achieved by building trust and continuous dialogue among the actors with interconnected but potentially divergent interests or viewpoints ( Brouwer etal., 2015). A multiactor approach involves working directly with farmers, managers, civil society groups ( e.g. youth, indigenous groups, and women); nongovernmental organizations ( NGOs); and scientific, policy, and business communities ( EIPAGRI, 2020). Their involvement in analysis, codesign, piloting, and upscaling of promising CNRFS will be highly relevant for promoting new CNRFS. The knowledge and experience of key agrifood actors combined with scientific knowledge will help to develop applicable best practices. Setting up sustainable MAPs, however, is a significant challenge ( Reid etal., 2014), requiring a whole range of skills, support, structure, and process. The regional and sectoral needs and contexts ( environmental, socioeconomic, geographical, cultural) must be considered from an early stage in the process of transition to CNRFS. The process should ensure that all relevant food systems stakeholders are actively engaged so that: • potential improvements to existing food, farming, and cropping systems can be jointly identified together with all stakeholders engaged in the MAPs. The crosssectoral representation in MAPs and use of systemic solutions will ensure that cocreated solutions will go far beyond mere technological innovations and that a crosssectoral agrifood chain ( markets, consumer, demand) perspective is applied ( European Commission, 2017). • it becomes easier to build on the existing MAPs ( including youth and women organizations, government agencies, small medium enterprises ( SMEs), producers, processors, retailers, food service providers, consumers), rather than creating new ones. Comparable structures comprised of representatives from producer associations, farmer innovation/ learning circles, and supply chain initiatives, already identified, should be engaged ( Nagothu etal., 2018). In line with the multiactor approach, defining and prioritizing the research needs together with the MAPs should be done simultaneously, including piloting the most appropriate combinations of solutions to accelerate the transition to CNRFS ( Nagothu etal., 2018). Specific care should be taken to engage young professionals ( e.g. young farmers, young fishers, young researchers, young entrepreneurs), SMEs, consumers, and citizens. 16 Udaya Sekhar Nagothu et al. Stakeholder perceptions about climate change While drafting this book chapter, farmers, scientists, and government agencies in some of the rice growing regions in Piedmont, northern Italy, and the Odisha and Assam provinces in India, were contacted during SeptemberOctober 2021. The purpose was to seek their opinion and perceptions on the current climate crisis and associated vulnerability and the implications of the Sixth IPCC report. In general, stakeholders in both India and Italy perceived the climate crisis as an immediate threat– exhibited by temperature changes, i.e. long dry periods alternating with unexpected intensive rainfall, warmer in the winter months and during early spring. Farmers, whether in Italy or in India, viewed that changes to climate will have a serious and direct influence on food production due to extreme climate variability. According to the respondents, farmers will be one of the communities most affected by the climate crisis because it is difficult to plan and grow crops in highly variable environments. During the discussions, farmers and government agencies suggested combating climate crisis with climateneutral solutions in agriculture that can create maximum impact– and able to address both adaptation and mitigation simultaneously ( to reduce GHGs and store carbon in the soils). Some of the measures suggested were ( i) minimum tillage of the soil, ( ii) growing climate resilient crop varieties with short duration ( to reduce GHGs and fix soil carbon), ( iii) diverse crops, cereallegume rotations, and ( iv) mulching with biomass to increase organic matter in the soils and enhance soil health. Wherever possible, farmers were of the opinion that these practices should be combined with agroforestry to increase agribiodiversity. One farmer practising organic rice farming in Piedmont suggested that incentives should be given for regenerative organic agriculture, training agricultural technicians who could, in turn, assist farmers in the green transition movement. The farmers also expressed that exploitation of alternative energies such as solar and wind in the agriculture sector should be explored as they contribute to reduction of GHG emissions. Although there are incentives or subsidies, they are not directly given to farmers or to support actions that can help in combating the climate crisis. Overall, the farmer and other stakeholders’ perception was that investments for scaling up climateneutral agricultural technologies that can reduce GHG emissions are going to be a challenge. Farmers in the two countries also expressed concerns that current agricultural insurance programmes do not cover crop damages and losses due to climate extremes. During the interviews, stakeholders expressed that in Europe it may be possible to tap the European funds for the Regional Rural Development Plan for supporting farmers to reduce GHG emissions ( European Commission, 2017). The current Horizon Europe programme provides an opportunity for scientists and stakeholders across the EU to cooperate on research and development to develop carbonneutral and green technologies ( European Commission, 2021). Whereas in countries such as India, although subsidies exist in the farming sector, it will Climate change impacts on agriculture 17 be challenging to access funding for reducing emissions from agriculture, as the country priorities are different compared to the EU region. It can be worse in African regions, where funds are even more limited. The EU is in the forefront when it comes to policy support ( EU level and national) to address the climate crisis. In irrigated regions, it will be important to make regulations for water use and irrigation and improve efficiency. Farmers during the interviews expressed that access to climateneutral technologies, biobased solutions, and inputs are important to reduce GHG emissions from the agriculture sector. Outline of the book This book is divided into different thematic chapters with a common objective and at the same time cover crosscutting issues related to technology, naturebased solutions, socioeconomic and policy perspectives relevant for upscaling the CNRFS. The first chapter provides a comprehensive review of the concept of climateneutral farming systems, main sources of GHG emissions, risks, and transition pathways to develop and promote CNRFS that can contribute to relevant SDGs ( especially SDGs 2, 13, and 15) and policy implications. This is followed by several chapters demonstrating promising CNRFS in rice and other food crop systems, based on experiences from different regions/ countries including South and SE Asia, Europe, and Africa. A separate chapter discusses the relevance of value chain analysis and integrating crosscutting issues, including stakeholder engagement and multiactor partnerships, and market and policy perspectives relevant for upscaling the CNRFS. Towards the end, the last chapter summarizes the key messages and lessons learnt from each chapter with specific policy recommendations and framework conditions necessary to be put in place to upscale the innovative CNRFS at a systemic level. Conclusions Achieving the major changes required to sufficiently reduce GHG emissions to meet the necessary targets may be more challenging for agriculture than for other sectors. In addition, the agriculture sector has a number of other complex objectives to consider alongside climate goals, including food and nutritional security, biodiversity, and the livelihood of farmers and farming communities. Rather than just dwelling on how we produce our food, we must change the way and what we eat, how we reduce food wastage, how we manage our forests and carbon sinks, and how we apply nexthorizon technologies. But we need to act swiftly; otherwise, emissions in agriculture will continue to grow and contribute to heating the planet to dangerous levels. DOI: 10.4324/9781003273172-2 Introduction Soil is one of our most important natural resources that provide us with vital goods and services to sustain life on land. If soils are healthy and sustainably managed, they can provide adequate food, clean water, habitats for biodiversity, and other important ecosystem services while contributing to climate resilience, adaptation, and mitigation ( Stolte etal., 2016). Soils act as source and sink for greenhouse gases ( GHGs) such as carbon dioxide, methane, and nitrous oxide ( Oertel etal., 2016). As a source, soil emits nitrous oxides from applied nitrogen fertilizers and as sink, soil increases carbon sequestration including carbon storage via fixation and organic fertilizer addition while reducing environmental footprints from rice cultivation. Rice is one of the staple foods of India that occupies about 24% of its total cropped area and contributes 42% of total food grain production. Being inputintensive crop, rice requires around 15– 20 kg of nitrogen to produce 1,000 kg of grain ( e.g., Peng etal., 2010). Most Indian soils contain lowtomedium plant available nitrogen ( N), and therefore the yield potential of rice or other crops largely depends on the exogenous application of nitrogen fertilizers ( Panda etal., 2019). Rice cultivation alone accounts for 37% of the total N fertilizer consumption in India ( FAI, 2018). However, more than 60% of this applied N is lost to environment in the form of N2O, NH3, and NO3. The conventional practice of rice cultivation in India involves ponding water between 5 and 7 cm depth in the soil for a considerable part of the growing period. Such soil microenvironment accelerates the processes of nitrogen transformation and its losses through nitrification, denitrification, volatilization, leaching, and runoff, which has resulted in low nitrogen use efficiency ( NUE). NUE of a cropping system is defined as ‘ the proportion of all N inputs that are removed in harvested crop biomass, contained in recycled crop residues, and incorporated into soil organic matter and inorganic N pools’ ( Cassman etal., 2002). As we are aware, use of fertilizer N for crop 2 Precisionbased soil and nutrient management tools for enhancing soil health while reducing environmental footprint Amaresh Kumar Nayak, Sangita Mohanty, Mehreteab Tesfai, Rahul Tripathi, Anjani Kumar, and Udaya Sekhar Nagothu Precision-based soil and nutrient management tools 25 production influences soil health primarily through changes in organic matter content, microbial life, and acidity in the soil ( Bijay Singh, 2018). Soil health and nitrogen management Soil health is defined as the continued capacity of soils to function properly and provide the required ecosystem services and goods ( EC, 2021). We take the soil services for granted, but in fact soils are nonrenewable and a threatened resource globally. The effects of climate change are putting further pressure on the soil resources and overall health of the soil. Most of the agricultural soils in the world are unhealthy, mainly because of unsustainable soil management practices. Some of the soil health improving practices generally adopted by farmers include conservation agriculture ( minimum soil tillage, residue mulching, crop rotations), intercropping with legumes, trees alley cropping, green manuring, and composting, which have a potential to reduce the exogenous application of mineral N fertilizer applications ( refer Chapter8 of this book). However, farmers do not receive any incentives for adopting such soil practices. Nitrogen is one of the most limiting nutrients for rice production and is a significant source of N2O ( a potent greenhouse gas: GHG) from agricultural soils. The direct N2O emission from synthetic N fertilizers used in agriculture has been estimated to be 0.9 N2O Tg N per year ( Syakila and Kroize, 2011). One of the nonpoint sources of pollution that cause serious threat to water environments is reactive N losses in the form of NO3. During the green revolution, nitrogen fertilizers were one of the key drivers to food production and have transformed the Indian agriculture to become the worlds’ second leading food grain producer. Nitrogen fertilizer consumption in Indian agriculture witnessed a whooping increase from 3.4 million tonnes ( in the late 1970s) to 16.9 million tonnes in 2017– 2018 ( Figure2.1). The trend will continue to increase further to attain the national yield target of 350 million tonnes 0 2 4 6 8 10 12 14 16 18 20 0 50 100 150 200 250 300 1974-75 1976-77 1978-79 1980-81 1982-83 1984-85 1986-87 1988-89 1990-91 1992-93 1994-95 1996-97 1998-99 2000-01 2002-03 2004-05 2006-07 2008-09 2010-11 2012-13 2014-15 2016-17 N consumption (mill. tonnes) Total food production (millio n tonnes) Total food grain production(million tonnes) N consumption( million tonnes) Figure2.1 Trend of total food grain production and fertilizer N consumption in India: 1974– 2016. Source: Fertilizer statistics ( 2018– 2019). Data adapted from https:// www.faidelhi.org/ statistics/ statisticaldatabase 26 Amaresh Kumar Nayak et al. of food grains ( cereals and pulses) in India by 2050, to feed around 1.8 billion people ( Kumar and Sharma, 2020). During these years, not only the consumption of fertilizer N will increase tremendously but also the flow of reactive N from agroecosystems and associated environmental losses. However, the increased food production during the Green Revolution ( e.g., by applying nitrogen fertilizers) was at the expense of environmental degradation. It has caused severe degradation of land and water resources, soil pollution, and high levels of GHG emissions ( Rahman, 2015). To address these challenges, research on nitrogen fertilizer management focused more on nutrient stewardship principles that entail right rate, right time, right methods, and right source ( 4R) of nutrient application ( IFA, 2009). The abovementioned 4R principles of nutrient stewardship ( Box 2.1) are not new. This chapter, however, attempted to present and discuss contextspecific precision nutrient management tools and techniques that can effectively support the 4R principles in the context of rice cultivation to improve soil health while reducing environmental footprints. The 4R principles could be applied using precisionbased tools such as remote sensing, Geographic Information System ( GIS), Global positions systems ( GPS), and simulation modelling. One of the key factors in implementing precision nutrient management is the ability to provide timely information regarding spatial distribution of crop N status within a field. From this perspective, determining plant N concentration by proximal or remote sensing techniques is much more appealing than the traditional destructive chemical analyses on soil/ plant samples considering the cost and time required. Box 2.1 4R Nutrient Stewardship principle 4R Nutrient Stewardship is a new innovative approach for fertilizer best management practices that considers economic, social, and environmental dimensions of fertilizer management and is essential to sustainability of agricultural systems. The concept is simple: apply the Right source of nutrient, at the Right rate, at the Right time, and in the Right place. All farmers– irrespective of the size of farm, knowledge and awareness levels– consider what fertilizer to apply, how much, when, and how before making a fertilizer application decision in any crop. The 4R Nutrient Stewardship principles connect these fertilizer application decisions to scientific principles and guide the application decisions to specific crops, soils, and local site. Moreover, the four ‘ rights’ provide a simple checklist to assess whether a given crop has been fertilized properly. Asking ‘ was the crop given the right source of nutrients at the right rate, time, and place?’ helps farmers and advisors to identify opportunities for improvement in fertilizing each specific crop in each specific field. Source: Adapted from Sapkota etal. ( 2016) Precision-based soil and nutrient management tools 27 Moreover, a declining trend of NUE in terms of partial factor productivity and recovery efficiency of nitrogen in the Indian agriculture ( Bijay Singh, 2017) calls for a more precise nutrient stewardship approach in the context of rice cultivation that ensures environmental sustainability and improves soil health. N fertilizer recovery efficiency ( REN) is defined as ‘ percentage of fertilizerN recovered in aboveground plant biomass during the growing season’ and partial factor productivity of N ( PFPN) also called agronomic N use efficiency ( AEN) is ‘ the ratio of crop yield per unit of applied N fertilizer’ ( Cassman etal., 2002). Understanding the reasons for the declining trends of NUE and the prognosis for improving them depends on knowledge of the factors that govern N demand and supply in rice cropping systems. The objectives of the chapter are to review and analyse research findings in precision nutrient management tools and techniques with special focus to N fertilizer use efficiency in rice cultivation. The chapter also discusses soil management interventions that can improve soil health while at the same time reduce environmental footprints and their policy implications for largescale adoption. Methodological framework The 4R Nutrient Stewardship framework was applied in the Norwegian funded Resilience project ( www.resilienceindia.org) in the case studies of Odisha state ( India) by adopting best management practices for soil and nutrients focusing on Nitrogen. The 4R principles aim to enhance production, increase NUE, and increase farmer profitability while reducing environmental footprints ( Figure2.2). • Critical stage based • Real time Application (CLCC, riceNxpert) • Deep placement • Root zone application • Foliar spray • EENFs • Controlled Release Fertilizers (SCU, NCU ) • USG, Urea briquette • Modeling approach • STCR • SSNM • RS based N management zone Right Rate Right Time Right Source Right Place 4R Nutrient Stewardship Figure2.2 Framework of 4R Nutrient Stewardship for enhancing N use efficiency. Source: Authors’ own compilations. Soil Testbased Crop Response ( STCR), SiteSpecific Nutrient Management ( SSNM), Remote Sensing ( RS), Customized Leaf Colour Chart ( CLCC), Enhanced Efficiency of N Fertilizers ( EENFs) that includes SulphurCoated Urea ( SCU), NeemCoated Urea ( NCU), and Urea Super Granules ( USG). 28 Amaresh Kumar Nayak et al. The precisionbased tools/ techniques for N management ( Table2.1) were assessed using PFPN or AEN and REN which are relatively easy to measure and are often used as indicators of NUE. PFP AE kg grainyield (ha/kgNappliedha) N11 1 or N=−− − ( 2.1) RE( ))100 0 UUF NN N =− × ( 2.2) where UN is the plant N uptake ( kg ha−1) measured in aboveground biomass at physiological maturity in a plot that received N at the rate of FN ( kg ha−1), and U0 is the N uptake measured in aboveground biomass in a plot without the addition of fertilizer N. Results and discussion In this section, selected research findings on NUE in rice growing areas of India and other Asian countries were reviewed and discussed. In addition, research data from the Resilience project ( www.resilienceindia.org) were analysed to show the performance of precisionbased tools and soil management practices in Odisha. The soil management practices used were conservation agriculture ( e.g., minimum tillage, notill farming), crop diversification ( including crop rotations and intercropping), crop residues mulching, composting, green manuring, and biofertilizers. Table2.1 Basic principles of precisionbased tools/ techniques for N management Precisionbased tools Principles and applications Soil testbased crop response approach Precise fertilizer recommendations are made after the establishment of a significant relationship between soil test values, added fertilizer nutrients, and crop response for a particular soil type ( Singh etal., 2021) Sitespecific nutrient management approach Supplying plants with nutrients to optimally match their inherent spatial and temporal needs for supplemental nutrients by using different tools such as remote sensing, GPS, and GIS systems ( Verma etal., 2020) Leaf colour chart A diagnostic tool used to determine N level in rice plants relative to greenness of the leaves, containing at least four panels of colour, ranging from yellowish green to dark green ( Nayak etal., 2013) Sulphurcoated urea Slowrelease fertilizer made by coating urea with sulphur and wax that increases NUE, improves plant growth, and reduces water pollution ( Shivay etal., 2016) Neemcoated urea Nitrification inhibitor which increases yield, uptake, and use efficiency of applied N fertilizer in rice ( Meena etal., 2018) Urea super granules Fertilizer applied at 8– 10 cm soil depth saves 30% N, increases absorption rate, improves soil health, and ultimately increases rice yield ( Sarker etal., 2012) Source: Authors’ own compilation from different literatures. Precision-based soil and nutrient management tools 29 Precision tools for nutrient management Several precision tools and techniques were tested in the Resilience project to assess and guide farmers in the realtime crop N need in line with the 4R Nutrient Stewardship principles. These include from simple/ easytouse and inexpensive diagnostic tools like the leaf colour chart to highly sophisticated optical sensors for precisionbased fertilizer recommendations using dronemounted sensors. i Leaf colour chart The leaf colour chart ( LCC) monitors relative greenness of a rice leaf and can be used as an indicator of the crop N status for determination of crop N demand in the season. However, the critical colour for N application may vary with cultivars, agroclimatic situations, and growing season and varieties grown. This requires cultivar specific standardization of LCC and calibration and validation of critical colour code. In response to this, a customized leaf colour chart ( CLCC) was developed by the Indian Council of Agricultural Research, National Rice Research Institute ( ICARNRRI) based on leaf colour analysis of hundreds of rice varieties ( Nayak etal., 2013). Results from field trials showed yield advantages of 0. 5– 0.7 t ha−1 with CLCCbased N application ( 25% lower than the normal recommended dose of N) ( Nayak etal., 2017; Nayak etal., 2018), which implies less cost of fertilizers for farmers and reduced environmental footprint. The CLCCbased ureaN application increased yield by 10– 13% in direct seeded rice ( DSR) and 10– 11% in puddled transplanted rice ( PTR) over conventional systems ( Mohanty etal., 2017). However, when neemcoated urea ( NCU) was applied based on CLCC recommendations, the yield advantage further maximized to 21– 23% for DSR and 15– 16% for PTR ( Mohanty etal., 2021). A possible explanation for higher yield could be attributed to the synchronized application of NCU, which reduces nitrification but increases plant available N, which results in higher PFPN or AEN. The performance of LCCbased N application compared to blanket application in terms of increasing grain yield and enhancement of NUE is shown in Table2.2. Depending upon crop management and agroclimatic conditions, the realtime N application using LCC can potentially increase yield by 10– 22% ( Mohanty etal., 2018) and save N fertilizer consumption by up to 50 kg ha−1 ( Bijay Singh etal., 2003). Similar studies by Kumar etal. ( 2018) also observed significantly higher grain yield of rice with CLCCbased N application, compared to blanket method of N application. The values for NUE ranged from 7.9% ( REN), 44% ( AEN), to 57% ( PPFN) under no basal/ basal + LCC ( 3– 4) based top dressing ( Table2.2). The low RE could be a consequence of greater N losses via nitrate leaching and N2O emission. This is in line with results from a study by AndrésBarbieri etal. ( 2018) who reported that RE was 29% ( on average) for urea which is low because of greater N mineralization from organic matter, N losses by denitrification, or immobilization. An application of N fertilizer with NCU using CLCC readings reduced N2O emission by 13– 14% in DSR and 16– 23% in PTR ( Mohanty etal., 2017). 30 Amaresh Kumar Nayak et al. Though DSR reduces CH4 emission as it uses less water during initial cropping, it can increase N2O emissions. The CLCCbased NCU application addresses the tradeoffs between CH4 and N2O emissions by translating their emissions into global warming potential ( GWP). In other words, minimum cumulative radiative forcing of the two gases on GWP is the possible option to minimize the tradeoff and effect of GHG emissions ( Susilawati etal., 2019). Moreover, the CLCCbased NCU application minimized yield loss, and resulted in 20– 25% reduction of GHG index through DSR ( Mohanty etal., 2017). Thus, the GHG index ( GHGI) that compares GWP and grain yield shows a lower value for DSR, implying that DSR mitigates GHG emission and produces more rice. Research on LCCbased N application in other rice growing areas of Asia also showed similar results about saving of N. For instance, savings of N by up to 25% by Alam etal. ( 2006) and 8.3% N by Sen etal. ( 2011) using LCCbased N management in different rice genotypes compared to the prescribed dose of N application ( 120 kg N ha−1). Moreover, the rice grain yields were 4.8 t ha−1 and 4.3 t ha−1 with variety NDR359 and Sarju52, respectively. Since the CLCC is user friendly to smallscale farmers, several state government departments, Indian Council of Agricultural Research institutes, and state agricultural universities in India have taken the initiatives to develop regionspecific CLCC and are upscaling it through various schemes ( Figure 2.3). Today, more than 500,000 units ( cards) of the Indian Rice Research Institute ( IRRI)- LCC type have been produced and distributed to farmers through collaboration with the National Agricultural Research and Extension Systems. The IRRIHyderabad, India centre developed a fivepanel modified LCC for irrigated rice. Similarly, the Punjab Agricultural University ( PAU) has come up with a sixpanel LCC for major food crops such as rice, wheat, and maize. Studies in the Punjab state of India indicated an average saving of 30 kg N ha−1 due to the use of the PAULCC. Table2.2 Performance of LCCbased N application compared to blanket N application Application method Grain yield increase (%) NUE enhancement (%) References Basal + LCC ( 4.0) based top dressing 20 15– 57 ( PPFN) Ali etal. ( 2017) Basal + LCC ( 4.0) based top dressing 22 7.9 ( REN) Mohanty etal. ( 2018) Basal + CLCC (≤ 3.0) based top dressing 10– 13 8. 9– 12.4 ( REN) Mohanty etal. ( 2021) No basal + LCC ( 4.0) based top dressing 12– 16 19– 44 ( AEN) Shukla etal. ( 2004) No basal + LCC (≤ 4.0) top dressing 11.3 13 ( REN) Bhatia etal. ( 2012) REN: recovery efficiency of N, AEN: agronomic efficiency of N, PPFN: partial productivity factor of N. Source: Adapted from several sources. Precision-based soil and nutrient management tools 31 The CLCC developed by ICARNRRI ( Cuttack, Odisha) provides cultivarspecific N recommendation for rainfed lowland, submerged/ flood prone lowland, rainfed upland, and irrigated rice of eastern India ( Nayak etal., 2013). So far, more than 200,000 units of CLCCs were distributed in several states of eastern India. ii Androidbased mobile app: riceNxpert Androidbased realtime N application ‘ riceNxpert’ app developed by the ICARNRRI under the Resilience project gives recommendations for inseason N application on the basis of leaf colour analysis. The riceNxpert is a costeffective app for realtime N application, is user friendly, has a potential for N < 100 CLCC number 100 - 250 250 - 500 500 - 1500 1500 - 3000 3000 - 5000 > 5000 400 400 Kilometers200 0 Figure2.3 Spread of CLCC across India. Source: Authors’ own compilation. 32 Amaresh Kumar Nayak et al. wider adaptation, and avoids the need for purchase CLCC every year. Research results showed that riceNxpertbased N application enhanced rice yield by 6. 6– 23.8% over RDN application and by 38% over normal farmers’ practice ( Nayak etal., 2021). This implies a yield advantage of 0. 5– 1.1 t ha−1 over RDN, and the riceNxpertbased N application in fact can give monetary benefits ranging from INR 9,000 ha−1 to INR 20,000 ha−1 (~US$ 118– 263) over RDN. Moreover, riceNxpert has a potential to cut down N use by 15– 25% in rice production and hence bring significant reduction of India’s subsidy bill for urea. Farmerled field experiments using riceNxpert in eastern India have increased crop yield and PPFN by 12– 13% compared to RDN ( Figure 2.4). However, trials conducted using riceNxpertbased N application in the research farm have enhanced PPFN by 30– 40% and REN by 9– 15% compared to RDN. The performance between riceNxpert and CLCC on crop yield and NUE ( AEN or PFPN) was compared, and results are presented in Figure2.4. iii Chlorophyll meter and SPAD meter The chlorophyll meter and the soil plant analysis development ( SPAD) meter are also realtime N application tools/ techniques. The chlorophyll meter provides the relationship of chlorophyll content of leaf with that of N contents which is more of quantitative indicator for crop N status. The SPAD meter estimates chlorophyll content of leaf in the field by measuring difference in light attenuation at 430 ( spectral transmittance peaks for chlorophyll a, b) and 750 nm wavelength, nearinfrared spectral region ( Schröder etal., 2000). SPAD with threshold 36 could save N fertilizer by 20– 35% while maintaining the same level of yield and improves REN by 14– 19% ( Ghosh etal., 2013). iv Comparative performance of LCC, riceNxpert, and SPAD The performances of realtime N application tools such as riceNxpert, CLCC, and SPAD meter were compared under field trials in the Resilience project ( Figure2.5). The difference in the performances of the three tools in 0.0 1.0 2.0 3.0 4.0 5.0 6.0 RiceNxp ert CLCC RDN Farmers' practice Grain yield (t ha-1) N management strategy 0 10 20 30 40 50 60 70 80 RiceNxp ert CLCC RDN Farmers' practic e PPFN(kg kg-1) N management strategy Figure2.4 Grain yield and PFPN of rice under different N application strategies. Source: Field data from Resilience project. Precision-based soil and nutrient management tools 33 terms of grain yield in the two rice varieties ( Naveen and Swarna Sub) was nonsignificant ( Figure2.5). However, the mean difference in grain yield was statistically significant ( P<0.05) between the tools and RDN. There was on average an 8– 13% increase in grain yield using the precisionbased tools over RDN. The grain yield of Swarna Sub variety was higher than Naveen variety in all realtime N application tools including RDN but not significant ( P<0.05). Studies comparing realtime N management tools between SPAD and CLCC are limited and showed varying results. For instance, Patil etal. ( 2018) observed that N application using LCC ( threshold 4) produced 8.5% higher yields and using SPAD ( threshold 40) produced 5% higher yields than RDN application. An LCCbased application saved 30 kg N ha−1, while SPAD saved only 10 kg N ha−1 compared to RDN application. This indicates the need for situationspecific standardization of SPAD threshold for N application. An application of 30 kg N ha−1 at ≤3.0 LCC led to additional application of 42 kg N ha−1 over RDN and contributed to a yield increase by 3. 5– 19.8%, whereas an application of 30 kg N ha−1 at ≤35 SPAD produced 0. 6– 15.4% higher yield than RDN ( Jahan etal., 2018). This implies that rice crop showing less than 4 LCC reading requires more N application than using SPAD meter. Other studies conducted by Ali etal. ( 2015) showed that applying 30 kg N ha−1 at <4 LCC saved up to 40 kg N ha−1, whereas using SPAD ( reading < 37) savings increased to 70 kg N ha−1 while producing similar yield. In other words, applications of N using SPAD ( with 35– 37) save more N than LCC (<4) based applications without yield loss. Other precision tools and approaches Green Seeker is another precision tool used to assess the realtime crop N ( Box 2.2). It is an optical sensorbased tool that can be used to calculate season N requirement as per sitespecific need of the crop. 0 1 2 3 4 5 6 Naveen Swarna Sub 1 Grain yield (t ha-1) RDNriceNxpertCLCC SPAD Figure2.5 Comparative performance of realtime N application tools in relation to grain yield of rice varieties: Naveen and Swarna Sub 1. Source: Field data from Resilience project. 40 Amaresh Kumar Nayak et al. i Precisionbased tools/ techniques for nutrient management The precision nutrient and soil management techniques discussed in the chapter have demonstrated advantages in terms of yield advancement, resource saving, enhancement in carbon stock, improvement in soil health, and reducing environmental footprint. Some of the precision nutrient management technologies involve high cost, sophisticated instruments, advanced data collection and analysis. However, data generated using these technologies will be useful for validation and ground toothing while devising largescale remote sensingbased sitespecific recommendation. The advent of remote sensing system such as unmanned air vehicles equipped with multispectral, hyperspectral, and thermal sensors can deliver realtime data at the spatial scale required for precision nutrient management. The precisionbased tools/ techniques have considerable adaptation and mitigation potential that could be exploited by providing policy support, adequate funding, infrastructure and extension, and farmer training support as needed. Government policy support and open collaboration with stakeholders at all levels will facilitate adoption of precision soil and nutrient management practices in agriculture. ii Soil health improving practices Agroecological approaches, such as conservation agriculture, with good agronomy and soil management practices such as zero tillage, crop diversifications, and residue mulching have shown an increase in carbon storage and sequestrations, and reduction in GHG emissions and GWP. This is in relation to the emission of methane from rice paddies and nitrogen losses from inefficient use of nitrogen fertilizers. India’s commitment for the NMSA– achieving its NDCs, and attaining the goal of zero emission by 2070– can be supplemented to great extent by promoting costeffective precisionbased tools/ techniques with suitable soil health improving practices. In this connection, there is a need to investigate lowcost precisionbased tools/ techniques for the effective implementation of soil health management practices that are user friendly. Acknowledgements The chapter has benefited from the results of the Resilience project field trials in Odisha. The authors would like to thank field enumerators and lead farmers involved in the field demos. At the same time, they acknowledge the support of the Norwegian Ministry of Foreign Affairs/ The Norwegian Embassy, New Delhi for funding and support to the Resilience project in India ( 2018– 2023). References Alam, M.M., Ladha, J.K., Foyjunnessa Rahman, Z., Khan, S.R., Khan, A.H. and Buresh, R.J. 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Yadav, D.B., Yadav, A., Vats, A.K., Gill, G. and Malik, R.K. ( 2021) ‘ Direct seeded rice in sequence with zerotillage wheat in northwestern India: addressing systembased sustainability issues’, SN Applied Sciences, vol. 3, 844. DOI: 10.4324/9781003273172-3 Introduction Paddy rice agriculture needs to respond to two issues relevant to climate change: one is to reduce greenhouse gas ( GHG) emissions, and the other is to save water. Paddy fields are an important source of methane ( CH4), which is one of GHGs responsible for global warming. Though nitrous oxide ( N2O) is also one of GHGs released from the agricultural fields ( Nishimura, 2004), the carbon dioxide equivalent of N2O released from rice paddies is lower than that of methane ( Quang etal., 2019). Therefore, methane is the focus in this chapter. Wetland soils are the main natural source with an estimated emission of 100– 200 Tg·year– 1, whereas the other sources are oceans, forest soils, termites, and wild ruminants. Of the anthropogenic emissions, domesticated ruminants ( 65– 100 Tg·year– 1) and rice fields ( 25– 150 Tg·year– 1) are responsible for 15– 40% of the total emissions. Human activities, including the expansion of paddy rice, played an important role in the observed longterm methane trend over the past two millennia ( Sapart etal., 2012). Hence, the need to reduce methane emissions from paddy fields is critical for mitigation ( Runkle etal., 2019). The production and consumption of methane in soils is caused by the metabolic activities of soil microorganisms. Soil organic matter is decomposed by a series of microbial activities, and methane is finally produced by methanogenic bacteria under strongly reducing conditions. When redox potential drops to less than −150 mV ( Gupta etal., 2021) or −200 mV ( Jean and Pierre, 2001), the methanogenesis process starts. After the production of methane, some of it is consumed by methanotrophs in oxidized zones ( rhizosphere, lower part of culms, soilwater interface, and submersion water) ( Jean and Pierre, 2001), and some of it is released to the atmosphere. In planted rice fields, there are two pathways of methane from soil to atmosphere: ebullition loss by the release of gas bubbles, and plant transport, into the roots by diffusion and conversion to methane gas in the aerenchyma and cortex of rice plants and concurrent release to the atmosphere 3 Organizational alternate wetting and drying ( AWD) irrigation management in rice by water user groups for reducing methane emission and water saving Kimihito Nakamura, Le Xuan Quang, and SokenMatsuda 46 Kimihito Nakamura et al. through plant micropores ( Davamani etal., 2020; Gupta etal., 2021). At the beginning of the crop cycle, when rice plants are small, the main transfer mechanism is bubble formation and vertical movement in the bulk of the soil. Diffusion through the aerenchyma becomes the dominant process, which is responsible for more than 90% of the methane emitted during the reproductive phase of the rice plant ( Cicerone and Shetter, 1981; Jean and Pierre, 2001). The amount of methane released from rice paddies depends on the redox status of the soil, so, if properly managed, it can be controlled by ponding water management. Draining the continuously flooded rice paddies once or more during the ricegrowing season would reduce global emissions by 41 Tg CH4 year−1 ( Yan etal., 2009). Therefore, rice paddy water management is very important for climate mitigation. Paddy rice cultivation uses a large amount of water. There is a concern that climate change will increase the frequency of drought risks ( Aryal etal., 2020), resulting in the loss of stable production of rice. Though paddy rice is conventionally grown in lowland systems under continuously flooded conditions, rice can be successfully grown with less water by the adoption of new technologies and various watersaving approaches which have been tested and disseminated ( Ishfaq etal., 2020). Watersaving irrigation to maintain rice productivity is required with increase in extreme weather events leading to droughts ( Bouman and Tuong, 2001). Alternate wetting and drying ( AWD) has been attracting the attention of scientists and farmers as one of the promising watersaving management methods. In this chapter, the focus is on AWD irrigation. The chapter discusses the different options for the organization of irrigation water management for AWD implementation based on experiences from Japan and Vietnam, and the challenges in AWD adoption followed by potential pathways and conditions for upscaling AWD. Alternate wetting and drying The AWD was originally proposed by the Irrigated Rice Research Consortium ( IRRC) of the International Rice Research Institute ( IRRI) as a water management technique for waterscarce areas ( Enriquez etal., 2021). In AWD, irrigation is applied intermittently with a period of nonflooding, whereas in traditional cultivation, the paddy is continuously flooded during the cropping period. Thus, in AWD continuous flooding is maintained for about two weeks after rice transplanting and about two weeks before and after the flowering period. The reason for keeping the fields flooded for two weeks after planting is to suppress weeds and to improve seedling growth. The temporary nonflooding during the cropping season is already practiced in several countries, including China, India, and Japan ( Richards and Sander, 2014). In Japan, for example, the drying of rice fields is carried out for about two weeks from about one month after transplanting. This is called the midseason drainage. The purpose of the midseason drainage is to suppress the production of hydrogen sulfide and organic acids due to soil reduction, and to create oxidative conditions in the soil, which inhibits root rot, AWD irrigation management in rice 47 promotes root elongation of the rice plant, and suppresses the development of nonproductive tillers ( Shindo etal., 2017). Furthermore, by hardening the surface of the rice fields, harvesting can be carried out smoothly using a harvester even if the field is flooded until the late stage of maturity. Insufficient midseason drying leads to excessive number of stems, which in turn leads to lodging, white underdeveloped grains, additionally weak rooting, and a soft soil surface when the rice reaches maturity. If water is drained early before harvesting, the vigor of the rice will decline in the latter half of the maturity period. Furthermore, the intermittent irrigation with alternating supply of water and oxygen is applied after the midseason drainage, except for the period before and after the flowering period, to keep the vigor of the rice plants intact. However, since most Southeast Asian countries customarily use continuous flooding throughout the cropping season, a nonflooding period is effective in saving water. The AWD method can contribute to reducing methane emissions since the aerobic soil environment is formed due to the nonflooded period and the methane production is suppressed. As shown by Enriquez etal. ( 2021), studies conducted in various countries have shown that AWD can reduce GHG emissions and irrigation water use without significant yield loss. Yagi etal. ( 2020) conducted a metaanalysis, which indicated that water management options, including single and multiple drainage approaches such as AWD, significantly reduced methane emissions by 35% as a mean effect size based on 31 regionspecific cases selected for the analysis. The widely publicized standard technique for intermittent irrigation is to install a field water tube ( 30 cm long, 15 cm in diameter, either plastic or bamboo pipe with drilled holes) to monitor the water level in the paddy plot and to irrigate water when the water level is 15 cm below the surface until the ponding depth is 3– 5 cm. This is called the safe AWD ( Rejesus etal., 2011). A depth of 15 cm is the standard to avoid rice yield loss. To reduce yield loss, it is important to level the paddy field surface properly and not to allow dry areas during flooding. The area available for AWD increases in the dry season ( Sander etal., 2017). In other words, the effect of AWD varies depending on climatic conditions, especially the amount of rainfall. Challenges for adopting AWD AWD is based on the knowledge that rice is tolerant to nonflooded conditions ( Kürschner etal., 2010), and does not involve major changes in irrigation facilities or additional costs. However, it requires careful planning and managing irrigation schedules. It is a technique that can be implemented if farmers are aware of the AWD advantages and have a strong motivation. It is not easy to change the mindsets of farmers to switch from the conventional continuous flooded irrigation to AWD because of the risks of poor growth due to soil drying, and overgrowth of weeds and pests. Even if water management is seen as a potential measure to reduce GHG emissions and recommended to farmers, the effects cannot be seen in the short term. Hence, it is difficult for farmers and local agencies to feel the 48 Kimihito Nakamura et al. direct and visible benefits. In addition, it is necessary for farmers to monitor the water level in each plot and manage water intake as needed, which can be labor intensive when there are many plots to be managed. Therefore, it is not easy to convince farmers to adopt the AWD system. The incentives for farmers to adopt AWD also depend on the irrigation system, the water availability, and the associated water pricing scheme. In the case of gravitydriven canal irrigation, there is no incentive for farmers to adopt AWD because the water usage fee is generally fixed per cultivated area or in some cases free of charge, and thus there is no change in the compensation for irrigation water saving, unless there is water shortage. Therefore, in a gravityirrigation system, the number of farmers who adopt AWD tends to be limited. However, in case where water is used by a pump, farmers have an incentive to adopt AWD because it can save the pump fuel or electric costs for drawing water. In general, water tends to be scarce in the downstream areas of an irrigation scheme or region compared to the upstream areas. Hence, when AWD is implemented in the upstream area, the possibility for the balanced distribution of water to the downstream area increases, which can contribute to reducing conflicts between the upstream and downstream areas ( Rejesus etal., 2014). In this case, it is necessary to foster motivation of farmers especially in the upstream area. For increasing the adoption of AWD, paddy fields suitable for AWD need to be well considered in terms of irrigation conditions, and simultaneously irrigation facilities need to be developed ( Yamaguchi etal., 2019). Additionally, adequate support by local government is essential, for example, training and education of farmers. The economic incentives, organizational strengthening, and improvement of the quality of irrigation infrastructure are important for the widespread adoption of AWD ( Enriquez etal., 2021). Organization of irrigation water management and AWD While individual farmers’ understanding and implementation of AWD is important, relying solely on each farmer to implement AWD, especially when there is no or insufficient direct benefit to the farmer, would not be easy for motivating farmers. Therefore, if the irrigation management organization or water user group can systematically distribute water according to the AWD cycles, the feasibility of AWD irrigation management can potentially be increased. Locally based irrigation management organizations such as water user group ( WUG) or water user association ( WUA) can play a key role in AWD adoption. The members of the water user groups are basically farmers, but in some cases, experts are hired to take on the role of water managers. Such water user groups can support irrigation projects to control water distribution; operate and maintain irrigation facilities ( Teamsuwan and Satoh, 2009); and maintain and manage agricultural dams, head works, pumping equipment, water division works, and main and branch irrigation and drainage canals. However, after the water is distributed from the diversion works, the management of intake and drainage of individual plots is generally implemented by individual farmers. AWD irrigation management in rice 49 Water user groups are considered important for the realization of participatory water management ( PIM). The policy of PIM has been adopted in several countries to stimulate a more productive and selfreliant irrigated agriculture, and an approach where farmers participate in all stages of irrigation development including operation and maintenance ( Hamada and Samad, 2011). For examples, the Government of Egypt attempts to solve challenges related to irrigation water shortage due to increases in water demands by strengthening WUA through the PIM policy ( Shindo and Yamamoto, 2017). In Korea, the irrigation management transfer from the local government to the rural community corporation is an emerging social issue ( Choi etal., 2016). Similarly, in Japan irrigation projects, all the irrigation facilities, including diversion dams, main and lateral canals, are transferred to land improvement districts ( LIDs), which are farmers’ autonomous irrigation associations with total responsibility for irrigation system management ( Kono etal., 2012). Gany etal. ( 2019) reviewed institutional reforms in the irrigation sector for sustainable agricultural water management undertaken in 14 countries and regions– including Australia, China, India, Indonesia, Iran, Japan, Malaysia, Mexico, Nepal, South Korea, Sudan, Chinese Taipei, Turkey, and Ukraine– focusing on the legal and organizational framework structure including WUAs for water supply services, PIM and management transfer, and publicprivate partnership. The study showed that water user groups have a significant impact on the local hydrological cycle and environment in terms of managing the supply of water and improving irrigation and wateruse efficiency. There are several good practices for water saving or conservation where water user groups can themselves manage irrigation and drainage water operations and water quality by directly controlling the water supply. The following are two examples of organized water management in the paddy field district area around Lake Biwa, the largest lake in Japan: block rotational irrigation ( BRI) and cyclic irrigation ( CI). Block rotational irrigation Lake Biwa covers an area of 670.25 km2 and the lake surface is roughly 85 m above sea level. The water of Lake Biwa was utilized for a variety of purposes, including domestic use, industry, agriculture, and power generation ( Shiga Prefectural Government, 2014). Water from the lake was used as a source of irrigation for rice cultivation drawn by electrical pumps. In one of the rice growing areas near the lake covering 1,244 ha, BRI was introduced after a severe drought in 1994 that caused water shortage problems. Irrigation pumps were operated and managed by a WUG ( LID). The water pumped from the lake was distributed to all areas simultaneously through 13 division works in the pipeline system. After the 1994 drought, LID decided to introduce the BRI to ensure a stable supply of water. In the BRI, the 13 terminal diversion work areas were divided into three blocks so that the command area of each block was almost equal. The operation schedule was managed such that water was delivered alternatively in two blocks on a given day during the period from midJuly to August, when good water supply was required 56 Kimihito Nakamura et al. 40 30 20 10 0 Daily average CH 4 emission flux (g CO2 m–2 d–1) C1 W1 S1 2016WS 40 30 20 10 0 C1 W1 S1 2016SA Figure3.7 Daily average methane emission fluxes converted to the equivalent CO2 in the observation plots in each cropping season in 2016. WS is the winterspring season and SA is the summerautumn season. CI, WI, and SI are a conventional plot, weakdry plot, and strongdry plot, respectively. Source: adapted from Quang etal. ( 2019). 0 5 10 10 0 5 C1 W1 S1 2016WS C1 W1 S1 2016SA Yield of unhulled rice (× 103 kg ha–2) Figure3.8 Yields of unhulled rice in the observation plots in each cropping season in 2016. Error bars represent the standard deviation. WS is the winterspring season and SA is the summerautumn season. C1, W1, and S1 are a conventional plot, weakdry plot, and strongdry plot, respectively. Source: adapted from Quang etal. ( 2019). AWD irrigation management in rice 57 manual pump to irrigate water from the canal to each plot when the ponding water depth in his plot is low. The organizational AWD does not work if there is lack of cooperation between water managers and farmers. From the farmers’ questionnaire survey, some farmers indicated that they used manual pumps less frequently, suggesting that when the BRI worked, the water level in the canal rose to the downstream in each block compared to the simultaneous water distribution to all plots in the district without the block rotation. Thus, it showed that the BRI with proper operation of pumps and gates at the water division works enabled farmers to realize that they no longer need to operate small manual pumps at the individual plot level. Due to such complexity of the irrigation management, it is likely that there was no clear effect of organizational AWD management on ponding water depth varies and no difference in methane emissions in the cropping seasons, except in 2016. The results of 2016 showed the potential of organizational AWD. Matsuda etal. ( 2021) observed the ponding water depth, soil redox potential, and methane emission in 2017 in this district, and found that the methane release could have been suppressed by a continuous nonflooding period of three to eight days after the switch from the flooded state to the nonflooded state, and that the methane was reemitted after a continuous flooding period of 14−22 days after the switch from the nonflooded state to the flooded state. Therefore, the amount of methane emission can significantly be suppressed by repeating the AWD cycles of nonflooding period of three to eight days and the flooding period of 13– 21 days. Such schedules of ponding water depth management for reduction of methane emissions would be useful for water managers. The organizational AWD can be upscaled if such data are measured and made available for different paddy growing regions. Potential pathways and conditions for upscaling AWD Multifunctionality and direct payments for environmental services Demonstration of the organizational AWD in the Red River Basin of Vietnam ( Quang etal., 2019) showed that if minor changes were made in irrigation facilities by introducing water diversion facilities, and if pumps and gates of the division works can be properly managed by WUGs, ponding water depth can be managed as needed to suit AWD cycles through the BRI without individual paddy plot water management by individual farmers. The results in such situation showed that the AWD management could significantly contribute to the reduction of methane emissions without major operation costs. In addition, this method enables sufficient water supply for each block, which is expected to avoid the water shortage that has occurred in the downstream areas in the district. To upscale this type of water management to larger areas, it is desirable that water management organizations be financially incentivized or subsidized to implement such environmentally friendly water management. It is also necessary to support the construction costs of necessary minor changes needed in the irrigation 58 Kimihito Nakamura et al. facilities, which can contribute to the reduction of GHG emissions for reducing global warming. Matsuno etal. ( 2006) reviewed various multifunctionalities of agriculture and the positive impacts of management measures such as flood control, groundwater recharge, soil erosion prevention, landslide prevention, water quality protection, organic waste decomposition, climate mitigation ( heat island prevention), biodiversity conservation, landscape formation, and regional development. Some of the major negative impacts include GHG emissions and water pollution of surface water and groundwater due to runoff and infiltration of fertilizer and pesticide components. A study by OECD ( 2003) indicated that the payment for environmental services ( PES) can be justified if the following three conditions can be demonstrated: ( 1) the agricultural production and multifunctionality are strongly linked; ( 2) the loss of agricultural production can significantly reduce multifunctionality; and ( 3) the government support for enhancing multifunctionality and reducing negative impacts is essential. Furthermore, cross compliance is a policy mechanism to encourage farmers to meet certain conditions ( e.g., environmental requirements) in return for governmental support payments that had developed in the United States and also gained political attention in the European Union and was developed as a policy instrument ( Meyer etal., 2014). This also implies that it is justifiable to provide incentives in terms of financial support to farmers and water management organizations that practice AWD properly to maintain and enhance multifunctionality and in turn can reduce GHG emissions and water pollution. In Japan, based on the idea that agriculture and rural areas have the multifunctionalities, such as land conservation, water resource recharge, natural environment conservation, landscape formation, and that the benefits of these functions are widely enjoyed by the society at large, the government has introduced three direct payment systems. This is to support local conservation activities and continuation of farming to fulfill the multifunctionalities of agriculture and rural areas, and ensure that the multifunctionalities continue to be properly fulfilled, and to support structural reforms of continuing farmers. The first is the direct payment subsidy for multifunctional activities, which financially supports the collaborative and organizational activities to keep and enhance multifunctionalities and to improve the quality of regional resources. These activities are specifically the basic conservation activities such as mowing the slopes of farmland, the removal of mud in water channels, maintaining the surface of farm roads, extending the service life of agricultural facilities such as water channels, irrigation reservoirs, and others, and landscape formation. The list also includes some specific practices linked to rice cultivation, including the implementation of paddy field dams to enhance flood mitigation ( Yoshikawa, 2014), the installation of paddy field fishways for fishecosystem conservation ( Ohtsuka, 2014), cyclic irrigation system ( Hama etal., 2010; Hama etal., 2011), and groundwater recharge from paddy fields ( Iwasaki etal., 2014). The PES are provided to organizations composed of farmers and others. The second is the direct payment subsidy for farmers in the hilly and mountainous areas, which supports positive efforts to AWD irrigation management in rice 59 continue agricultural production activities in the hilly and mountainous areas where the population is aging and declining rapidly. The third is the direct payment for environmentally friendly agriculture, which supports agricultural production activities that are highly effective in reducing the environmental impact of agricultural production, preventing global warming, and conserving biodiversity, and aims to contribute to increasing soil carbon stocks. The requirements for this support include organic farming, cover cropping, composting, notill sowing of rice, and the prolonged middrainage drying in rice cultivations ( more than 14 days), which is expected to be effective in reducing methane emissions ( Itoh etal., 2011; Kunimitsu and Nishimori, 2020), in addition to reducing the use of chemical fertilizers and synthetic pesticides by at least 50% from the conventional level. Direct payments are made to the organizations by farmers who engage in such activities, as well as to single farmers and corporations with more than a certain cultivated area. Santos and Shimada ( 2019) estimated the economic effects of PES for environmentally friendly agriculture on income of rice farmers in Shiga Prefecture, Japan, in which farmers agreed on the following three points: ( 1) reducing the use of chemical pesticides and fertilizers to less than 50% of the conventional practice, ( 2) proper use and management of compost and agricultural wastewater, and ( 3) the agreement period is to be implemented for five years. The study in fact showed that the substitution of environmentally friendly agriculture in place of conventional rice farming had resulted in increased farm income due to the PES received. Kitano ( 2019) also showed that the direct payment program had a positive influence on the spread of environmental conservation agriculture in Shiga Prefecture. In Korea, the multifunctionalities of paddy farming have been recognized and the government has introduced a direct payment system for environmentally friendly agriculture to conserve water source and national park areas since 1999, including the minimization of using pesticides and fertilizer and the improvement of water quality for reservoir, stream, and groundwater ( Kim etal., 2006). Similarly, Xuehai etal. ( 2018) concluded that one of the most important approaches to agricultural green development in China is to shift the existing subsidy policy from one which aims to ensure the yield by purchasing at a protective price, to a green subsidy which focuses on agroecological compensation. The Vietnamese government passed a national policy on payment for ecosystem services in the hope of strengthening forest conservation, improving local livelihoods, and generating revenue outside of the state budget for nature conservation ( To etal., 2012). In Asian countries, the functioning of the PES for agriculture so far seems to be limited to Japan and South Korea. It is necessary to develop similar support mechanisms in other countries to support farmers that will be responsible for carrying out climate change mitigation and adaptation efforts, including organizational AWD in several countries. Since the reduction of GHG emissions has a global benefit, it is necessary to develop a framework at the global scale beyond the local or national level in the new initiatives to reduce methane from agriculture. 60 Kimihito Nakamura et al. Water management with tradeoffs Agricultural water management affects the soil moisture status, thus altering the soil redox status and chemical and biological reactions of the soil, and the unintended substances are sometimes produced. It has been shown that AWD may increase the emission of nitrous oxide ( N2O), a GHG, which has a greater warming effect than methane ( Sibayan etal., 2018). Balaine etal. ( 2019) mentioned that given the high early season methane fluxes, drying earlier may result in greater reductions of methane in wet seeded rice systems but this requires further study as there may be negative effects such as increased N2O emissions. Additionally, an increase in the nonflooding period may lead to an oxidative environment and may increase the production of nitratenitrogen ( NO3– N), which may leach into groundwater during reflooding and contribute to an increase in NO3– N in groundwater. AWD changes the anaerobic environment caused by continuous flooding and accelerates the nitrification process, which improved the consumption of ammoniumnitrogen ( NH4– N) and expedite NO3– N loading to the groundwater ( Wang etal., 2018). The bypass or preferential flow and strengthened nitrificationdenitrification nitrogen transformation processes because of AWD potentially increase the NO3– N loading to the groundwater ( Tan etal., 2013). However, Tan et al. ( 2015) estimated using HYDRUS1D that the increased NO3– N, which was formed from nitrification of NH4– N in drying and aerobic phase, can be easily denitrified to N2 or N2O in the wetting and anaerobic phase. In another study, Amin etal. ( 2021) showed nitrogen leaching depends on the drying spell in AWD irrigation. It will be necessary to study how AWD can be used to reduce the environmental impact of NO3– N and N2O. In some soils, the presence of toxic elements such as arsenic ( As) and cadmium ( Cd) can be absorbed by crops and become harmful to human health. The mobilities of As and Cd in soils depend on soil redox potential. Paddy rice in flooded soil is prone to As uptake in which reducing conditions increase As mobility through reductive dissolution of Asbearing Fe and Mn oxides and drying cycles create more oxidizing conditions that promote the precipitation of Fe and Mn oxides and subsequent retention of As, which limits As mobility and availability for plant uptake ( Evans etal., 2021). However, soil drying may mobilize Cd as sulfide in CdS minerals is oxidized to sulfate and AWD can increase Cd bioavailability ( Li etal., 2019). When As and Cd exist simultaneously in paddy soils, the water and soil management must be designed to inhibit crop absorption of both substances. Seyfferth etal. ( 2019) suggested that a less severe watersaving approach such as AWD in combination with rice residue amendment could limit Cd and As uptake without compromising yield. They mentioned the flooding plus mixed charred/ ashed rice husk might limit Cd concentrations in rice and the limited flooding plus Sirich rice husk might limit As concentrations in rice. In addition, climate change has already caused severe flood damage, and water storage in rice paddies is expected to be a significant factor in flood prevention in Japan. Efforts to control the amount of drainage from paddy plots as much as possible without damaging the growth of rice are attracting attention ( Yoshikawa, AWD irrigation management in rice 61 2014). It should be noted that water management is not only about saving water and reducing methane emissions, but also about recycling of nutrients that would otherwise have been lost through drainage water to the surface water, leaching water to the groundwater, or emissions to the atmosphere and other multifunctionalities of paddy rice farming. Therefore, it is necessary to develop more evidencebased scientific knowledge on how to optimize AWD water management with such tradeoffs in mind. Development of necessary information for water management For an organization to conduct efficient water management, it will be necessary to spatially understand the meteorological conditions, the cropping conditions in the area to be managed, and the characteristics of the field soil, especially the permeability of the soils, which is an important factor that defines the amount of water required. The use of remote sensing ( Nagano etal., 2015) and unmanned aerial vehicles can be effective for understanding the status ( Krienke etal., 2017; Campo etal., 2020). In addition to the estimations of the spatial distribution of the required water quantity by the remote information systems, it is necessary to comprehensively determine the water use status in the management area and the status of agricultural water utilization facilities. Besides, detailed information on the source water quantity, water level and flow rate in irrigation canals, water level in regulating reservoirs, flow rate in diversion works, groundwater level, and so on is to be regularly recorded in real time. A variety of hydrological models, which are sometimes coupled with crop model, have been developed for water resources management, agricultural water management, and crop management. Many physically based distributed hydrological models such as the Soil and Water Assessment Tool ( SWAT) ( Arnold etal., 1993), the Système Hydrologique Européen ( SHE) and MIKE SHE ( Abbott etal., 1886a, 1886b), Soil and Water Integrated Model ( SWIM) ( Krysanova etal., 1998), and others have been developed and widely applied. The WEPL distributed hydrological model, derived from the water and energy transfer processes ( WEP), coupled simulations of natural hydrological processes and water use processes by human activities ( Jia etal., 2006). Khadim etal. ( 2021) developed a numerical framework, based on a groundwater model using MODFLOWNWT ( Niswonger etal., 2005), coupled with the outputs of the DSSAT crop model ( Jones etal., 2003) for agricultural water management. Furthermore, to apply the hydrological models to Asian regions dominated by paddy fields, for example, Xie and Cui ( 2011) customized the SWAT model by incorporating new processes for irrigation and drainage. The development of an integrated hydrological simulation model including irrigation and drainage management in paddy and upland fields, and the operations of agricultural water facilities ( dams, head works, reservoir, water division works, groundwater pumps, and so on) in addition to the natural surfacesubsurface hydrological processes are necessary. Outputs from such models can provide accurate information that is necessary for water management organizations to operate AWD. 62 Kimihito Nakamura et al. ICT in water management With the advancement of information and communication technology ( ICT), it is relatively easy to implement not only remote acquisition of data such as water flow and water level at agricultural water utilization facilities, but also remote operation and control such as opening and closing of gates and valves and starting and stopping of operation. In Korea, smart agricultural water resources management systems have also been introduced in irrigation districts as the prototype projects managing and monitoring the irrigation system from the water resources to the irrigated fields and ICT can be an alternative solution to overcome vulnerability of agricultural water resources structures impacted by droughts and floods ( Choi, 2015). A study by Masseroni etal. ( 2018) evaluated the hydraulic, control, and economical performances of the automatic and remotecontrolled system applied for traditional rice irrigation in Italy. The study demonstrated that the automatic system allowed us to drastically reduce the time spent by workers for water level control and flow regulation and the price of the automatic irrigation system appeared to be in good agreement with respect to the willingness of farmers for innovation. Although there are many hurdles to overcome in terms of installation and running costs, it will be useful for organizational AWD in the long term as a laborsaving method if the operation of pumps and gates of diversion works can be automated while monitoring the water level in the canal and the paddy ponding water depth in the plots in the district. Furthermore, an automatic water supply system that starts water intake at a certain time, stops water intake when the water level in the paddy plot reaches the upper limit, and resumes water intake when the water level reaches the lower limit has been developed in paddy fields in Japan. It is expected to facilitate more efficient irrigation management ( Nishida etal., 2022). The ICT water management system is technically feasible for AWD management. Conclusions To reduce the contribution to GHG emissions from rice paddies, it is important to focus on paddy water management with particular attention to methane reduction. In addition, it is important to have the potential ability for watersaving paddy water management in response to climate change. To spread AWD in a wide area and continuously, the organizational AWD irrigation system by WUGs based on BRI with the operation of water diversion works along the irrigation channels. Since the reduction of methane emission by AWD contributes to the prevention of global warming, it might be useful to promote AWD by establishing a PES mechanism to benefit farmers at the national level for water management organizations and farmer groups that strictly implement AWD with cross compliance. Providing an appropriate paddy ponding management schedule considering AWD to water management organizations and farmers is necessary. It should be a specific water and soil management method according to the soil and climatic AWD irrigation management in rice 63 characteristics of the region, not only considering methane emission and water conservation, but also reducing the environmental load of nitrate nitrogen and nitrous oxide and crop uptake of Cd, which are caused by the tradeoff between the oxidative change of soil due to the nonflooding period increased by AWD. In addition, it is necessary to establish sensing and analysis technologies to obtain information on water consumption, especially from spatial and temporal meteorological and agricultural crop conditions; to construct and operate a hydrological model that can indicate water management for agricultural water use facilities and paddy fields based on the information; and to build a platform to ensure that water management organizations and farmers can easily implement the proposed appropriate water management using ICT. Acknowledgments AWD management demos were conducted under a joint initiative of the Institute for Water and Environment under the Vietnam Academy for Water Resources in Vietnam and the IndustrialAcademic Cooperative Research for Irrigation Water Management in Japan comprising Kitai Sekkei Co., Ltd. and Kyoto University. The project was supported by the Ministry of Science and Technology in Vietnam ( Grant Number: NĐT.06.JPN/ 15), and the Japan Society for the Promotion of Science ( JSPS) KAKENHI ( 16H05799). We are grateful for the cooperation of the farmers and the agricultural cooperatives involved, the Hinogawa River Basin LID, the Kamogawa River Basin LID, the Konohama LID, the Shiga Prefecture Office, the Kinki Regional Agricultural Administration Office of the Ministry of Agriculture, Forestry and Fisheries, Japan, JSPS KAKENHI ( 18H02297 and 20H03101), and “ Integrated Research Program for Advancing Climate Models ( TOUGOU program)” from the Ministry of Education, Culture, Sports, Science and Technology, Japan. References Abbott, M.B., Bathurst, J.C., Cunge, J.A., O’Connell, P.E. and Rasmussen, J. 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Hama ( 2021) ‘ Paddy ponding water management to reduce methane emission based on 72 Shyamaranjan Das Mohapatra et al. by the FAOinitiated IPM. In addition, the farmers’ abilities and capacity to use the information and implement the selected measures in a timely manner are equally important. According to Heeb etal. ( 2019), the crosssectoral approach in IPM that aims to reduce pestinduced crop losses will also improve ecosystem services and reduce the GHG intensity per unit of food produced and make agricultural systems more resilient to climate change. As we are aware, paddy rice or wetland rice is a vast humanmade wetland with ecological complexity. The rich diversity of arthropods in the paddy agroecosystem, both plant eating and predators, helps to keep their populations in balance, especially abundance of the former groups that provide a good source of food for the latter ( Thorburn, 2015). The generalist predators ( spiders, dragonfly, damselfly, water striders, etc.) in turn help to keep the rice pest populations below the economic threshold levels. Several species of hostspecific parasites and parasitoids play an important role within the complex ecological web. The behavior and population dynamics of the predatorpest species within an agroecosystem is heavily influenced by the type of soil, water and crop management operations used, including the agronomic management practices, and the use of external inputs, especially synthetic pesticides and inorganic fertilizers ( Heong etal., 2021). The lack of integrated measures to manage the pest with reliance on chemical pesticides alone will not be enough; rather, it leads to negative impacts on the environment and human health ( Gill and Garg, 2014). Therefore, increasing awareness about a holistic IPM approach and farmers’ capacitybuilding is important for successful adoption. In India, IPM trainings and awareness campaigns thus became a part of the nationwide IPM program, as evident from the trainings that were conducted during 1995– 2021 for scientists, extension workers, and farmers through formal courses, FFSs, and exposure visits ( Government of India, 2021). However, the results and outcomes of the trainings were not able to realize the expected outcomes in the field, because of the lack of systematic followup and other critical shortcomings. The rate of adoption of IPM technology by farmers varied and was influenced by age, education, involvement in communitybased organizations, and the ability to recognize the pests and farm size ( Rao etal., 2011). Other constraints linked to lack of trained extension officers on IPM, and poor farmer integration in the planning and implementation of IPM slowed down the IPM adoption. A conceptual framework for sustainable and climatesmart integrated pest management During the last 60 years, IPM development across several countries has illustrated how crop protection evolved over time with varied outcomes, including both success and failures ( Deguine, 2021). The main objective of IPM when it was first introduced was to reduce the overuse of synthetic pesticides. During the late 1990s, the importance of sustainable intensification in agriculture gained momentum ( Conway, 1999; Pretty and Bharucha, 2015). Consequently, the importance of environment and human health in IPM started to become a priority together with reducing crop damage and yield losses. More recently, with the emphasis on Integrated pest management in rice 73 climate action, new IPM programs are obligated to give due consideration to the impacts they would have on climate or vice versa. Hence, the IPM interventions must not only be sustainable and ensure environmental health but also contribute to GHG reductions and carbon sequestration ( Figure4.1). Figure4.1 illustrates a pathway for transition from conventional pest management ( PM) toward climatesmart and sustainable IPM. First and foremost, a good understanding of the potential of a healthy rice agroecosystem and its multifunctionality will be a necessary step in IPM. At the next level, an enabling institutional environment and policy support is essential for effective implementation and upscaling of any IPM program, including the timely and right advisory from scientific community and the genuineness of farmer participatory extension approaches used, targeted trainings, adequate investments, and necessary infrastructure. Th choice of IPM measures must be based on the needs of the rice agroecosystem with the appropriate combination of nature based, cultural, physical, chemical, and biological measures that not only help to improve the agroecological processes ( e.g., nutrient cycling, biological nitrogen fixation, soil carbon sequestration, and predator activity) but also contribute to overall sustainability of the agroecosystem ( Thorburn, 2015; Ketelaar etal., 2018; Heong etal., 2021). Habitat management in noncroplands The main objective here is to protect the ecosystem and biodiversity around the crop lands, especially the natural enemies and pests. A proper habitat management High pest incidence and crop losses, habitat destruction Lack of proper integration of pest management measures Monoculture of rice Deep tillage – harmful to soil biodiversity Unbalanced use of fertilizers-pollution Puddled paddy rice cultivation-higher GHG emissions¨ Excess use of synthetic/chemical pesticides Reduced crop losses, higher yields, healthier agroecosystem, reduced GHG emissions IPM with proper combination of measures Habitat management (non-croplands): by using Nature/ecosystem-based measures Habitat management (on croplands): by using agro-ecological/cultural /physical measures Crop and pest management: by using cultural/ physical/biological/monitoring tools Direct control with bio-based pesticides and other measures Enabling institutions (Public and private sector, research, extension, and development organizations to support climate smart and sustainable IPM Conventional IPMClimate smart and sustainable IPM Transition to sustainable IPM Figure4.1 A conceptual framework showing a transition from conventional pest management to climatesmart and sustainable IPM ( authors’ own compilation). 74 Shyamaranjan Das Mohapatra et al. helps to establish a functional link between crop and noncrop lands, improves the interactions of pestpredators, and, thereby, provides a healthy diverse habitat for both beneficial insects and alternative hosts for pests. Agroecosystembased measures are normally recommended for habitat management that include maintaining graminaceous flora around paddy fields, planting catch crops, and growing green manure crops like Chinese milk vetch Astragalus sinicus after the rice harvest, which can provide shelters for native natural enemies ( Huang etal., 2005). The numbers of species, individuals, and diversity index of natural arthropod enemies were found to be significantly greater in Chinese milk vetch fields than those in winter fallow fields ( Yuan etal., 2010). Furthermore, the milk vetch fields provide favorable conditions for natural wintering enemies where natural enemies account for 67.9% of the total insect species. Field bunds around rice farms host a number of arthropods that can effectively regulate the rice pest populations increasing the parasitoid population within the rice fields ( Gu etal., 1999; Xuetal, 2004; Zhu etal., 2015). Habitat management within the croplands The importance of soil biodiversity conservation in agriculture has not been appropriately considered in the past. The focus has been mostly on increasing crop productivity through agricultural intensification, whereas a sustainable intensificationbased IPM approach requires the adoption of nature conservationbased measures, including conservation agriculture ( CA) practices ( e.g., intercropping, zero tillage, or minimum tillage), that benefit the diverse soil fauna and flora and improve overall soil health in the croplands. Studies have shown that microbial diversity and biological activity are higher in undisturbed soils under no tillage or minimum tillage compared to soils subject to deep plowing ( Nsabimana etal., 2004; Spedding etal., 2004). Also, the abundance of mesofauna was greater where CA was practiced in comparison to compacted soils ( Rohrig etal., 1998). One of the important ecosystem services generated by the soil flora and fauna is the carbon sequestration in the soils, which can be a significant contribution to the mitigation efforts in agriculture ( IPCC, 2022). Spiders constitute over 90% of the natural enemy population in rice fields, which play an important role to contain the insect pests. Simple measures such as fixing of straw bundles vertically with bamboo sticks after 15 days of rice transplanting (@20 bundles/ ha), 15 cm above the water level, helped harboring 10– 30 spider adults, 8– 10 spider egg masses, 500– 600 spiderlings, and 20– 30 earwigs ( Tanwar etal., 2011). Similarly planting wild sugarcane ( Saccharum spontaneum) twigs of 4– 5 feet in height and 4– 5 cm in diameter after 15 days of transplanting in rice fields harbor the predators at the time of occurrence of leafroller, thereby suppressing the incidence of pest. This was common in parts of India, as evident from a study that showed 90% of farmers in the Benakunda village of the Ganjam district in Odisha adopted the practice of planting wild sugarcane ( Mohapatra etal., 2019a). Another example is the Caseworm pest incidence in West Singhbhum district, Jharkhand state, India where farmers use fresh parasi leaves Integrated pest management in rice 75 ( Cleistanthus collinus) once 5– 10 days after transplanting on the insectinfested rice field using a dosage of 5 kg leaves per 100 m2 to control the pest ( Mishra etal., 2020). Similar cultural measures for habitat management within the rice fields were adopted by farmers, for example, protecting naturally occurring plants on the farm bunds, which act as a source of food for natural enemies. Avoiding insecticide sprays in the early crop stages helps maintaining arthropod population, thereby decreasing the incidence of pest such as BPH development. In Vietnam, a multimedia campaign was used to encourage farmers to stop early season spraying, and the results showed that in provinces where the campaign was implemented, farmers reduced insecticide sprays by 53% ( Heong etal., 1998). A balanced application of chemical fertilizer ( major and micronutrients) can improve the utilization efficiency and rice plant vigor and enhance the resistant ability ( de Kraker etal., 2000). For example, there is a positive relationship between rice resistance to pests and application of silicon in rice. Silicon can induce rice resistance or tolerance to adversities ( Thripathi etal., 2014), such as stem borer, rice blast disease ( Zhang etal., 2003), and the white BPH eggs laid on rice culm ( Yang etal., 2014). Thus, micronutrients have multiple benefits, such as reduced pest damage and increased yields. Crop and pest management By using a good combination of cultural, physical, and biological measures, it is possible to manage the rice crop and relevant pests through IPM programs– for example, changing planting and harvesting timings to avoid peak pest incidence, use of pest and diseasetolerant rice varieties, use of biopesticides, rice stubble management. Rice stubbles left in the field after harvest serve as the main overwintering sites for several rice stem borers. Rice stubble management using mechanized harvesting can significantly reduce the initial population by reducing overwintering sites ( Guo etal., 2013; Wu etal., 2014; Xu etal., 2015). Agroecological based measures such as intercropping and crop rotations help in suppressing pest populations, and damage to rice crop ( IPCC, 2022). Some examples of rice crop and pest management are discussed later in this chapter from the authors’ own field study. Monitoring and forecasting of insect pests Insect pest monitoring these days is becoming an important component in IPM programs as it increases the knowledge of the pest dynamics in the field that helps growers in decisionmaking– for instance, the intervention thresholds to counteract a given insect pest infestation, optimizing the control strategy and reduced use of chemical inputs ( Mohapatra etal., 2016). Monitoring data can also be used to develop phenological models that can predict insect population outbreak, which in turn will provide additional information to improve the control techniques and optimize insecticide usage ( Dent, 2000). Tools and methods such as ePest Surveillance, Smart Light trap, and other devices for monitoring pests are 76 Shyamaranjan Das Mohapatra et al. now available for improved pest monitoring and forecasting. Similarly, light traps are useful in monitoring rice stem borers and planthopper populations. The classic monitoring approach of insect pests is by placing a series of traps in infested rice fields which are monitored manually. More recently, software and image recognition algorithms have been used to support automatic trap usage to identify and/ or count insect species from pictures and enable realtime and online pest monitoring ( Mohapatra etal., 2019b). Farmers these days can opt for any model of light trap based on the cost and availability of their power source, i.e., direct electricity, battery, or solar energy as per the requirement/ situation, with the costs varying from approximately US$12 to US$200 ( Mohapatra etal., 2019b). These traps are ecofriendly, portable, easy to operate and no special skills are required for installation. Based on the peaks of its lighttrap captures, forewarning models can be developed, for example, a model for rice leaf folder was developed using the lighttrap captures and weather variables such as maximum temperature, relative humidity, and sunshine hours, which could explain 99% of the variability in leaf folder lighttrap peaks in a study in Punjab, India ( Singh etal., 2015). Similar models were analyzed for BPH to inform farmers about the pest incidence and measures to be taken ( Thakur etal., 2020). In general, pest weather relations have been analyzed through empirical models, which behave on a locationspecific manner ( Chander, 2010). The models such as DYMEX can forecast the impact of climate on the dynamics of the rice yellow stem borer population and generate a monthly or seasonal trend pattern, with R2 values of 0.74 ( calibration) and 0.88 ( validation) ( Nurhayati and Koesmaryono, 2017). In addition, mobile applications are becoming popular in agriculture, for example, the “ riceXpertApp” developed by the National Rice Research Institute ( NRRI) in Cuttack is a multilingual mobile app with a “ pest solution” module to identify the pest and estimate the right amount of pesticide to be used. The solution can help to create prescriptions automatically for different rice pests ( Mohapatra etal., 2018, 2019b). One of the main objectives of the app is to increase the precision of pest control and avoid the use of chemical pesticides wherever possible. Direct pest control with biobased products Another category is the nontoxic biobased products that can manage pests and improve plant health without using chemicals that can harm people and benefit insect populations. The biobased pesticides used are naturally occurring substances, such as microbes, bacteria, and plant extracts. The use of biobased products promotes plant and soil health, while managing weeds, pests, and plant diseases in a broad range of agricultural, horticultural crops, as part of an IPM strategy. Biological insecticides are now widely accepted and commonly used in agriculture and increasingly available in the markets in India. Products derived from the neem tree ( Azadirachta indica) were traditionally used for controlling pest in agriculture because of the presence of active ingredient Azadirachtin in neem tree ( Morakchi etal., 2021). Seed treatment with biobased products helps Integrated pest management in rice 77 in reducing pest attack and damage to rice crop at a later stage. For example, rice seedlings rootsdipped in 5% neem seed kernel extract for 12 hours reduced egg laying and hatching of green leafhopper Nephotettix virescens ( Abdul Kareem etal., 1988). Similarly, seed treatment with Trichoderma viride was found to be effective in controlling the rice seedborne fungal pathogen, Rhizoctnia solani, and foliarborne bacterial pathogen like Xanthomonas oryzae pv. Oryzae ( Bhat etal., 2009; Tanwar etal., 2019). The studies reported that making the products easily available to farmers and regular trainings about their usage would increase adoption of these environmental friendly products. Bacterial and microbial formulations are replacing chemical pesticides as their availability is increasing in India. In addition, new trails and initiatives with microbial formulations by private and public research agencies across India are showing promising results, which will help scientists to include the new products in IPM programs. A recent field assay of the National Rice Research Institute, India, Bt formulation showed LC50 (×107) values as 3.77, 5.29, 4.83 and 4.93, 4.42, 4.72 against third, fourth, and fifth instar larvae of Cnaphalocrocis medinalis respectively ( Ghosh etal., 2017). The isolates of Beauveria and Metarhizium spp. were more effective in infecting 80– 93.3% rice leaf folder larvae, compared to other entomopathogenic fungi that infected only 20– 23.3% larvae in 96 hours ( Sahoo etal., 2013). In recent years, application of Trichogramma to control insect pests in rice has become popular again since it meets the needs of food, ecological, and environmental safety standards ( Wang etal., 2015). The devices and technologies for releasing Trichog ramma in rice field have been improved ( Zhang etal., 2003), including the use of devices for releasing Tr ichogramma with nectar food supplement and the recent techniques for releasing Tr ichogramma by unmanned aerial vehicle in China ( Li etal., 2013). The nectar food application studies carried out to improve the biological control function in a ricebased ecosystem ( Gurr etal., 2016), especially on flowering plants ( Zhu etal., 2012; Chen etal., 2014) and type of nectar food spray ( Seagraves etal., 2011), will be useful to develop ecofriendly IPM programs in the future. A field study carried out in India by Kumar and Khan ( 2005) on the release of Trichogramma japonicum and T. chilonis (@ of 50,000 numbers/ ha) showed a significant reduction in the tiller damage caused by yellow stem borer ( Scirpophaga incertulas), and folded leaves by rice leaf folder ( Cnaphalocrocis medinalis) from 50.1% to 61.3% and from 63.8% to 75.5%, respectively. Similarly, reduction in tiller damage and folded leaves varied from 78.1% to 81.6% and from 72.6% to 81.8%, respectively, when egg parasitoids were released at 100,000 numbers/ ha. There are numerous examples of nonchemical measures used and available traditionally by farmers to control pests and diseases. We need to revisit them, document the local knowledge and evidence systematically, and thereby put them together with the scientific methods of pest control while developing new IPM programs for rice and other crops. Mechanisms must be in place to acknowledge the traditional practices and incentivize farmers that adopt them, in their efforts to reduce the use of chemical pesticides. 78 Shyamaranjan Das Mohapatra et al. Impacts due to climatesmart and sustainable IPM The impacts of a wellplanned climatesmart and sustainable IPM on the rice agroecosystems can be multipronged. A right combination of IPM measures can have positive impact on the environmental, sociocultural, and economic sustainability dimensions simultaneously ( Figure4.2). Figure4.2 illustrates some of the benefits, which are possible because of IPM. These indicators can be used to develop a baseline and subsequently evaluate the impact due to the implementation of IPM. The impacts can be direct and/ or indirect, which can be assessed using quantitative and qualitative indicators. Predominantly, it was the yield and crop damage that was given importance in IPM programs, whereas impacts on the environment and human health were often ignored. It is important to show the farmers, stakeholders, and policy makers about the multifunctionality that could generate a wider support for IPM programs ( Swaminathan, 2000; IAASTD, 2008; NRC, 2010). In recent years, IPM has been evolving into a more broad based integrated pest and production management, where not only pest management but multiple benefits to sustainable production are also targeted. Studies combining selected IPM measures such as minimum tillage, agroforestry, border crops outside croplands, crop rotation with legumes, the system of rice intensification, and so on showed significant reductions in water savings, improved soil nitrogen, and soil biodiversity ( e.g., abundance of earthworms), besides reduced pesticide use and increase in yield ( Kartaatmadja etal., 2004; Pretty and Bharucha, 2015). The hidden health benefits of reducing or “ no pesticide use” strategy are not easy to be assessed, which can be significant in most cases and the benefits can be enormous in some cases. A recent assessment of the government IPMcomponents Nature-based, cultural, physical, biological measures,biopesticides Farmer participatory extension services (FFS, VKCs) ●Healthier ecosystem ●GHG emissions reduced ●Carbon storage in soils increased ●Greater resilience ●Biodiversity protected ●Increased knowledge of ecosystem biodiversity ●Pesticide free agri-products ●Reduced human health problems ●Farmer innovation increased ●Increased resource use efficiency ●Organic products with better markets ●Increased farm income ●Enhanced value chain Environmental sustainability Socio-cultural sustainability Institutional and policy support -Research -Public - privatesector services (inputs, credit, marketing) Economic sustainability Figure4.2 Potential impacts due to climatesmart and sustainable IPM. Source: Authors’ own compilation. Integrated pest management in rice 79 showed that IPM initiatives in India have led to an increase in crop yields from 6.72% to 40% in rice, reduction in the use of chemical pesticide by 50– 100%, and an increase in the use of biopesticides from 123 million tons in 1994– 1995 to 7,682 million tons by 2018– 2019 ( Government of India, 2021). IPM impacts and results from Resilience and other projects in India IPM modules involve combining several measures targeting habitat management both around and within the rice farms, in addition to the direct or specific measures included to manage the pests and diseases. In some cases, it targets a particular pest, where two or more measures are combined to manage the damage due to a single pest, whereas in others combined effort targets to manage multiple pests. In this section, some examples of field demos of selected IPM modules in rice and their results from the ongoing Resilience project in Odisha, India ( www.resilienceindia.org) which is funded by the Government of Norway are presented. As per the baseline survey conducted under the Resilience project, the major insect pests observed were rice stem borer, rice bug, and termites, and diseases such as rice blast, brown spot, and false smut that cause substantial losses to rice in the project areas were observed. About 100 lead farmers were engaged in the training and demonstrations of selected IPM modules targeting particular rice pests in the project as described below. A simple IPM module was developed for managing brown spot disease in low land rice ecosystem, combining seedling dip in Pseudomonas fluorescens @ 3 × 106 cfu/ ml and clipping of seedling tips and selected spraying of chlorantraniliprole 18.5 SC ( soluble concentrate) @ 50g a.i. ( active ingredient) per hectare at 25 days after transplanting ( DAT). This module recorded lowest brown spot incidence ( 3.8%) compared to control treatment ( 12.0%). Similarly, another IPM module for rice stem borer, combining seed treatment with carbendazim @ 1 g a.i. (@ 2 g/ kg seed) and an application of chlorantraniliprole 18.5 SC @ 50g a.i at 25 DAT, recorded the lowest percent dead heart ( 2.4%) and white ear head infestation ( 2.0%) compared to control treatment, i.e., application of carbofuran 3G @ 3 g/ m2 ( nursery application) at 7 days before uprooting of seedling and thiamethoxam 25 WG @ 25 g a.i./ ha ( water dispersible granule) at panicle initiation ( PI) stage. Both the IPM modules– i.e., ( 1) chlorantraniliprole 18.5 SC at 25 DAT and Pseudomonas fluorescens @ 3 × 106 cfu and clipping of leaf tip at transplanting and ( 2) Carbendazim @ 2 g/ kg seed ( seed treatment) and carbofuran 3G @ 3 g/ m2 ( nursery application)– registered the higher yield compared to control treatment. Soil enzymatic activities such as dehydrogenase activity ( DHA) of soil also increased by 27% in treatments with chlorantraniliprole 18.5 SC @ 50 g a.i./ ha ( spray) over the control treatment with thiamethoxam 25 WG @ 25 g a.i./ ha. Similarly, fluorescein diacetate activity ( FDA) increased by 18% due to the application of chlorantraniliprole and carbendazim ( for seed treatment), and the use of Pseudomonas fluorescens over the application of Thiamethoxam and carbofuran 80 Shyamaranjan Das Mohapatra et al. ( soil application), thus safer to soils than in terms of the nontarget effect of these treatments on soil microbes and their activities. Chlorantraniliprole ( 18.5 SC) is a reducedrisk pesticide that belongs to the pyrethroid group and is considered safe to use in IPM. The overall soil microbial biomass carbon ( MBC) showed an increase because of the IPM measures. These IPM measures demonstrated a positive impact on the predators as evident from the increase in predator populations such as damsel fly; ground beetle like Paedarus sp.; predatory bugs ( Andrallusspinidens); and spiders such as Pardosapseudoannulata, Tetrag n ath a, Xanthopimpla, and Tetra stichus observed in higher numbers than the control plots. Another IPM module demonstrated in the farmer’s field at the Tangi block in Cuttack district, Odisha under the Resilience project involved a combination of pheromone traps (@ 8 traps/ ha) for monitoring yellow stem borer, combined with solar powered light traps and the biological agents Trichog ramma japanicum, an egg parasitoid at a dose of 1 gram a.i. (@ 100,000/ ha released three times at an interval of seven to eight days). A needbased application of foliar spray of flubendiamide 480SC @ 30g a.i. ha−1 against stem borer was recommended only when the damage due to stem borer was observed. In addition, farmers were advised to place straw bundles in the field to increase the spider population and also trained to collect nymphs and adults of rice gundhi bug mechanically by using hand/ sweep nets in the morning hours and reduce chemical spraying. Results in general showed that the fields with IPM demonstrated the advantages in terms of yield ranging from 4.9 t/ ha to 5.4 t/ ha compared to control farmers’ fields ( 4.8 t/ ha) that used conventional PM practices. Furthermore, compared to control plots, the use of chemical insecticide was reduced by about 1.5 applications in the IPM plots. Populations of natural enemies ( e.g., spider) doubled in the IPM demonstration plots. Pest populations in the IPMtreated plots were higher in the early stages, but gradually the numbers reduced than in the control fields toward the end of the cropping season because of IPM. This is in line with observations from other studies that compare IPMtreated and insecticidefree demos with conventional PM farms ( Horgan etal., 2017). Higher pest numbers at early crop stages are not generally considered problematic because rice compensates for insect damage during tillering and pretillering stages, particularly hybrid rice varieties ( Horgan etal., 2016). Farmers were generally positive about the IPM demo results that led to reduced pesticide use, increased cost effectiveness, and increased rice yields. Farmer engagement in IPM planning and trainings contributed to the adoption of IPM programs in the Resilience project villages in Cuttack. Policy measures in support of IPM Upscaling the IPM requires policy support and funding from the governments, and regular followup and monitoring of impacts. In Asia, awareness about the importance of IPM increased since the mid1980s, thanks to the effort of international agencies such as the FAO. Take, for example, the case of India, where Integrated pest management in rice 81 the central government has included IPM as one of the components in the overall Crop Production Programme since 1985 ( Government of India, 1985). The IPM program received a boost with the “ Strengthening and Modernization of Pest Management Approach in India in 1991– 92,” which was launched together with the establishment of 35 IPM centers across the country to support implementation. Further, the support for IPM was emphasized in the National Policy on Agriculture– 2000 and the National Policy for Farmers– 2007. The overall objective of IPM initiatives in India has been to increase crop production with balanced use of pesticides, minimize environmental pollution and occupational health hazards, and conserve ecosystem services. Although IPM is now a wellrecognized approach in India and other Asian countries both within the government and scientific communities, in practice it still has a long way to go; we need more efforts to achieve the desired impacts. The policy and programs so far appear to be promising and are a good basis on which the new climatesmart and sustainable IPM programs must be developed. A study by Rao and Rao ( 2010) in India revealed that only 3.2% of the farmers surveyed adopted IPM practices in various crops. Though IPM initiatives brought out changes in the farmers’ attitude in PM and help to reduce the use of chemical pesticides, there is a need for systematic followup to strengthen IPM adoption. The study recommended readdressing the policies for encouraging ecofriendly options and further strengthening extension services, involving farmers as one of the top priorities. This is similar to the findings of Panda and Rathore ( 2017), whose study recommended that IPM programs in India must be revised and made specific to farmer and the particular agroecosystem needs. Conclusion and way forward Experiences so far have shown that a participatory extensionbased IPM approach is the way forward to realize the full benefits, prevent yield losses in major crops such as rice, save on application of inputs, protect ecosystem, and reduce GHGs. Based on the past experiences, the future IPM programs must be prepared encompassing sitespecific based, cultural and physical measures combined with biological control and/ or plant origin pesticides that are environmentally friendly and climate smart. IPM technology and experiences generated by scientists working in national and international agricultural research centers must be combined with local knowledge and customized to farmer and agroecosystem needs through codevelopment for successful implementation. Wherever possible, new models and tools must be used to improve forecasting of pest and disease occurrence and increase precision in IPM programs. Further research is needed to explore the full potential of natural enemies, microbial insecticides, and tolerant cultivars. Incentives for reducing use of chemical pesticides and promoting use of biobased pesticides must be systematized. The net profits for the rice growers will increase by adopting IPM strategies properly, and thereby leading to reduced use of chemical pesticides while sustaining the yield. 88 Abha Mishra et al. drying ( AWD), have shown that a 6– 9 Mt/ yr reduction within the rice sector is possible ( UNEP and CCAC, 2021). Adoption of climatesmart practices has received considerable attention in the Asia region. In this regard, climatesmart agriculture ( CSA) has emerged as one of the strategies to address the emerging needs. CSA is composed of three main pillars: ( 1) sustainably increasing agricultural productivity and incomes; ( 2) adapting and building resilience to climate change; and ( 3) reducing and/ or removing greenhouse gas emissions, where possible ( FAO, 2016). The climatesmart agroecologicalbased System of Rice Intensification ( SRI) defines a way forward for smallholders to grow healthy crops with less inputs ( land, water, pesticides, synthetic fertilizers, labor and capital), and with greater appreciation and reliance on robust local ecosystem goods and services that suppress pests and diseases, that enhance soils, that support food security and rural livelihoods and, finally, that mitigate methane emission from the paddy system ( FAO, 2014; Thakur and Uphoff, 2017; Mishra etal., 2021). By producing stable crop yields with low external inputs, SRI also provides an opportunity for farm diversification, enhanced income generation and dietary diversity that addresses the nutritional needs of smallholders. Thereby, SRI can become the main climate change solution and support sustainable development ( Thakur etal., 2021). SRI is based on four agronomic principles: • transplanting young and healthy seedlings ( at 2.5 leaf stage) or direct sowing with relatively low seed rate; • shallow transplanting ( with minimum root disturbance) with wider spacing providing enough space and less competitive plant’s microenvironment to realize the fullest potential of seedlings/ seeds; • keeping soil preferably moist, not inundated, at least during vegetative stage to allow root systems to grow larger and healthier, later maintaining shallow water level, but never creating hypoxic soil condition, thus improving plant and soil health and mitigating methane emission; and • applying organic manure as much as possible to nurture the soil systems ( feed the soil to feed the plant) ( Stoop etal., 2002, 2011; Mishra etal., 2006, 2013). All four key principles are amenable for farmers’ experimentation, adaptation and adoption, as the process does not require any external physical inputs. These SRI practices– transplanting younger and single seedlings/ hill with wider spacing, or direct seeding with relatively lower seed rate, giving plants more space and avoiding continuous flooding– when implemented together have, in many instances, resulted in substantial increases in yield, and reduced GHG emissions ( Dill etal., 2013; GathorneHrady etal., 2016; Mishra etal., 2021). However, to have lasting impact, these ambitious goals need to be pursued in an enabling social context. Pretty etal. ( 2020) have argued that the political economy in past decades “ prioritized unfettered individual action over the collective” thereby harming many rural institutions and “ reducing sustainability and System of rice intensification 89 equity”. Offsetting this trend, Pretty etal. note that, in recent years, changes in national and regional policy have promoted the growth of social groups whose existence supports “ transitions towards policies and behaviours for global sustainability”. While their study cites integrated pest management ( IPM) as a catalyst in shifting the balance back from individual action to the collective, we propose that SRI is an important complement to IPM in achieving those social and economic objectives. Thus, the chapter outlines a conceptual framework for optimizing rice productivity through responsible management of ecosystem goods and services reflective of the rich biodiversity contained in healthy rice paddy fields. Furthermore, it shares onstation research findings, coupled with participatory action research and an outreach effort at scale that has empowered thousands of farmers in their rural communities to appreciate and responsibly manage sustainable rice production. Finally, the chapter concludes with a discussion about and recommendations for a better enabling environment to allow for a real transformation toward more sustainable intensification of rice production at landscape, national and global levels. Such a transformation aligns well with the action called for in the UN Decade of Ecosystem Restoration ( 2021– 2030) and is vital and urgent for the world to achieve the UN Sustainable Development Goals by 2030. Conceptual framework for optimizing the management of ecosystem goods and services and biodiversity in healthy rice paddies while mitigating the climate change Over the last 30 years, there have been widespread efforts to promote farmercentered agroecological innovation using Farmer Field School ( FFS) with several innovative efforts focused on the promotion of adoption of SRI ( FAO, 2019; Ketelaar etal., 2020). These efforts aim to involve farmers as agent to improve paddy productivity by managing household and environmental resources efficiently. Our earlier study ( Mishra etal., 2006) had conceptualized how the combination of cultural practices recommended in SRI increases the physiological efficiency of rice plants through enhanced root activity. The study also outlined many opportunities to enhance resourceuse efficiency using SRIIPM to be explored by farmers using the FFS approach. In this chapter, we will illustrate how the paddy fields change under SRIIPM practices. Emphasis is placed on holistic management approach of the paddy ecosystem. SRI fields that are managed without chemicals can enhance photosynthetic rate and capture more carbon and sequester more through enhanced physiological activity of roots and shoots ( Mishra and Salokhe, 2010, 2011; Mishra and Uphoff, 2013). Addition of organic matter, including compost, as much as possible would restore degraded soil biodiversity, rebuild soil organic matter and restore the soil’s microbiome to promote nutrients ( Figure5.1). By following alternate wet and dry ( AWD) water management practices, it is possible to improve the soil aerobic conditions, promote soil biodiversity and therefore reduce methane production and emission from paddy fields. Even under 90 Abha Mishra et al. shallow flooded conditions for short periods, the higher root activity would keep the rhizosphere aerobic facilitating methane oxidation and therefore less emission from the field. A healthier soil also means more CO2 is taken out, or sequestered, from the air. Avoiding large doses of pesticides by applying IPM principles would restore and enhance the balance between pests and natural enemies as discussed in Chapter 4. In this manner, empowered farmers combine IPM and SRI to promote above and below ground natural biodiversity. A healthy soil contains a vast number of diverse microbes, which work in exchange with paddy plants growing in the soil. Rice plants absorb carbon through photosynthesis, which helps them to grow, and excess carbon is transported to the soil, where it becomes organic matter. The carbon feeds the various microbes in the soil, which in return supply the plants with the nutrients they need. A healthy soil supports a balance among all the components of the ecosystem. These sustainable intensification approaches build on sound agronomy as well as on biodiversity and ecosystem ecology for the purpose of raising crop yields and land productivity while capturing and sequestering more carbon and reducing GHG emissions. Largescale adoption of SRI practices can be a major game changer in terms of achieving greater land productivity while addressing key environmental challenges, including climate change. Below findings from onstation research as well MICRO-ORGANISM DYNAMICS AEROBIC SOIL ENVIRONMENT (Wet/Dry) DETRIVORES SRI PLANT HIGHER YIELD Resilience to climate and other stresses Less CH4 emission from SRI field O2 O2 O2 O2 Beneficial microbes promote plant growth & protect from pathogens CH4 production (when excess water) Larger aerobic rhizosphere oxidizes CH4 Feed the soil to feed the plant Higher rootavailable nitrogen Lower leaves photosynthetically active Delayed senescence of shoots and roots More and heavier panicles Higher cytokinin production Healthy root systems = f (more organic matter in soil, fewer seedlings/ hill, wider spacing, AWD) = SRI FILTER FEEDERS HERBIVORES PREDATORS and PARASITOIDS Erect flag leaf, higher rate of photosynthesis ORGANIC MATTER Figure5.1 Healthy rice paddy fields under optimum management of ecosystem goods and biodiversity services facilitated by agroecological principlesled SRIIPM practices. System of rice intensification 91 as engagement at the regional level in the Mekong River Basin region provide some useful insights on the landscapelevel effects: how SRI can sustainably intensify rice production and mitigate GHG emission from the paddy fields. Onstation research findings on the effects of SRI practices on root architecture and its impact on methane reduction In the above section, we presented a model of a paddy production system that optimizes land productivity as well as the management of ecosystem goods and services and biodiversity contained therein while capturing and sequestering more carbon and reducing GHG emissions. Nurturing healthy root systems along with healthy soil is one of the priorities to realize the benefits that we have outlined in this model and the above explanatory section. In this section, we explore how healthy root systems, i.e., enhanced root growth through morphological and physiological plastic response observed under SRI practices, are linked to methane emission mitigation. Root growth can be altered through various mechanisms ( by genetic and by microenvironmental manipulation). But given climate change concerns, methane emission from paddy fields, as well as water constraints facing the rice sector in many countries, the most important crop management practice, which attracts major attention, from farmers, researchers as well as policy makers, is the cessation of continuous flooding, either through intermittent irrigation or by keeping soil moist but preferably not continuously inundated. The intermittent irrigation in rice or AWD is not something new. In fact, this has been supported earlier in some riceproducing countries in an attempt to reduce the volume of irrigation water used. The pros and cons of intermittent irrigation have been well reviewed and referenced in our previous published study ( Mishra and Salokhe, 2010). It has been suggested that intermittent irrigation or AWD can reduce water use in rice cultivation by 15– 25% without affecting yields, and can lower methane emissions by 30– 70% ( FAO, 2013). In addition, further reduction in methane emissions can be realized through plastic response of shoot and root, the latter resulting into a more aerobic rhizosphere ( Mishra and Salokhe, 2011). Research findings on the plastic response1 of rice plants that resulted due to change in water regimes documented that rice root morphology and physiology and consequently rice shoot growth are significantly affected by variations in soil water conditions ( Mishra and Salokhe, 2010, 2011). Root architecture ( root length density) and roots’ oxidizing activity rate are important factors influencing higher yields. Such responses are quite plastic in nature and vary considerably with varying water regimes and with varying soil microbial populations ( Mishra and Uphoff, 2013). Modifying water management to take advantage of plants’ inherent plasticity of morphological and physiological response can be one of the adaptive strategies for achieving higher yield under reduced water condition along with mitigation of methane production from rice fields ( Mishra, 2019a). The earlier findings have also shown that intermittent irrigation during vegetative growth stage along with sparse planting density of younger seedlings, i.e., 92 Abha Mishra et al. single seedling transplant/ hill with 20 × 20 cm spacing, increased root and shoot growth. These practices induce different levels of physiological activity, resulting into higher yields and higher dry matter production ( Mishra and Salokhe, 2010). Building on the earlier findings we estimated rate of oxygen release using the Kirk ( 2003) root’ model calculation to understand the implication of morphological and physiological plastic response on nutrient uptake and methane emissions from rice fields. Kirk ( 2003) indicated that for an aerobic rhizosphere, spacing is critical along with number of primary roots per plant. Keeping the standard estimation typically observed under average paddy fields in Asia,2 we calculated the rate of release of oxygen under different planting densities and water regimes. The calculation revealed that at flowering, the rate of release of oxygen per cm2 was higher under P2 planting density ( single seedlings/ hill with 20 × 20 cm spacing) in both IVF ( intermittent irrigation during vegetative stage) and CF ( continuously flooded) water regimes whereas it was drastically reduced at 20 days after flowering ( DAF) under flooded condition. The effect of spacing along with single seedlings/ hill had the maximum effect compared to other treatments. Typically, maximum rates of N uptake by rice crops are 40 pmol cm−2 ( soil surface) s−1. Therefore, if half the O2 released from the roots was used to nitrify NH4+ in the rhizosphere (( NH4+ + 2O2 → NO3− + 2H+ + H2O) and half the NO3− produced was recovered by the roots, an O2 release of 160 pmol cm−2 would be sufficient to nitrify half the nitrogen absorbed by the roots. This is one of the prerequisites, i.e., 50% N uptake should be in the form of NO3 to achieve the higher yield under any field condition ( Wang and Below, 1996; Briones etal., 2003). Furthermore, it is known that up to 90% of the CH4 emitted in rice paddies is released through rice plant transport ( Conrad, 2007), while between 19% and 90% of the CH4 produced is oxidized, with up to 75% of the CH4 oxidation taking place in the rhizosphere ( Frenzel, 2000). Accordingly, strategies to lower net CH4 emission from rice fields include reducing CH4 production, increasing CH4 oxidation and lowering CH4 transport through the plant. Among the CH4 emission mitigation strategies that do not compromise rice productivity, the introduction of drainage periods during the crop cycle appears to be the most efficient ( Neue, 1993). Thus, it has been estimated that intermittent drainage periods by applying intermittent irrigation in poorly drained rice fields could reduce to 10% of the agricultural CH4 emissions ( Kern etal., 1997). It is expected that the higher root activity rate ( Mishra and Salokhe, 2010) along with higher release of oxygen for a longer duration ( Figure5.2), as appeared in our studies, should further enhance CH4 oxidation in the rhizosphere because of the prolonged oxygenated rhizosphere. This benefit will be relatively higher under intermittent irrigation water regimes but even under flooded condition ( though relatively less) at flowering stage if intrahill competition is minimized to keep rice rhizosphere aerobic ( Figure5.2). Optimizing planting density per unit area through SRI not only enhanced root activity but also increased oxygen release under single seedlings/ hill planting option. Thus, maintaining an aerobic rhizosphere for longer duration would not System of rice intensification 93 only facilitate higher uptake of nitrogen in the form of nitrate and ammonium for higher biomass production but also support methane oxidation in the rice rhizosphere by 75– 90%. Thus, there will be negligible methane emission from the rice fields. Indeed, optimization in spacing and water management is needed in order to enhance the oxygen release in rhizosphere that benefits plants, soil microbes and environment without making it burden for plants as releasing oxygen in rhizosphere is an energyconsuming affair for plant. In addition, intermittent irrigation will reduce the aerenchyma formation rate ( Mishra etal., 2006). Since the aerenchyma acts as a channel for oxygen transport from the atmosphere to the roots and CH4 transport from the site of production to the atmosphere, reduced aerenchyma formation will lead to lowering CH4 transport through the plant. These benefits become more relevant in the prospective scenario where rice production needs to be increased with both reduced water applications and reduced “ climateforcing” practices. Scaling up through farmers’ participatory action research ( FPAR) for transition toward agroecologicalbased SRI methods As discussed above and reported by many, SRI is considered as one of the best currently available agroecological methodologies for sustainable intensification of ricebased farming systems that involve farmers as agents to improve productivity by managing environmental resources efficiently. We piloted several plot scale efforts in the Lower Mekong River Basin countries to explore the usefulness of SRI and IPM practices using the FFS approach for having farmers learn about sustainable paddy production ( Mishra and Kumar, 2009; Mishra etal., 2013). The outcome of these collaborative initiatives gave impetus for scalingup efforts to the regional level. To learn more about the SRI’s usefulness for fueling innovation IF-V Flowering 500.00 450.0 0 40 0.00 350.0 0 30 0.00 250.0 0 20 0.00 15 0.00 10 0.00 50.00 0.00 20 DAFFlowering P1 P2 P3 20 DAFFlowering 20 DAF IF-R CF Figure5.2 Effects of planting density. 94 Abha Mishra et al. at grassroot level involving smallholder farmers as a main agent, a regional collaborative project, funded by the European Union, was implemented in rainfed areas of the Lower Mekong River Basin ( LMB) countries ( Cambodia, Laos, Vietnam and Thailand) involving more than 15,000 smallholder farmers directly ( and 30,000 indirectly), researchers, extension personnel and development professionals, together with staff of relevant government ministries ( www. srilmb.ait.asia/). The sixyearlong project’s objectives were to fuel local innovation to produce healthier, more profitable rice crops with less energy and a lower carbon footprint by using the SRI method under rainfed conditions.3 The idea was also to learn and advance knowledge on technical, institutional and organizational innovation needed for shift from readytouse to tailormade solutions that address locationspecific issues along with global challenges. Keeping this in mind, local, national and regional innovation platforms were designed to systematize engagement and strengthen communication for fueling innovation. This was a network building effort that was initiated by the project and was expected to continue as a common meeting point at all levels. These platforms facilitated policy dialogues on food security, research for development, marketing improvements and extension capacity for the rainfed LMB region. More than 15 institutions ( academic, research and development) were involved in the sixyearlong farmers’ participatory action research ( FPAR) field trials located in the 33 rainfed districts of 11 provinces in the LMB countries ( Cambodia, Laos, Thailand and Vietnam). SRI’s agronomic principles were used as “ entry points” for such engagementled transition. The number of farmerparticipatory experiments conducted was more than 1,052 at >500 sites across the LMB region. As a part of this FPAR intervention, the common issues and interests expressed by farmers producing under rainfed conditions in all four countries were to achieve higher yield with reduced costs of production by reducing input use for cost saving and for making rice cultivation more efficient and profitable. Using results of baseline survey, including information generated through various groupdynamic tools such as subgroup discussion, visual tools and brainstorming sessions, a range of experimental options were selected for each of the target areas that revolved around the integration of a few SRI principles with existing conventional practices to be applied on a learning plot for locationspecific adaptation. As part of these field experiments, farmers were also encouraged to apply the full set of SRI principles on a demonstration plot which served as a “ test site” to show the full potential of SRI methods at smallholder farmers’ field level. For comparison purposes, the practices that were applied were categorized into ( 1) Baseline ( indicated as CP), ( 2) Farmer’s practices ( FP), ( 3) SRIdemonstration ( SRID) and ( 4) SRItransition ( SRIT). Baseline– the existing conventional management practices ( CP) generally followed in the target area as identified through the baseline survey prior to action research setup. Farmer’s practices ( FP)– the existing management practices generally followed in the target areas and set up by farmers as FP plots for comparisons purpose during the action research field experiment setup. System of rice intensification 95 SRIdemonstration ( SRID or SRI)– where the full set of SRI practices was applied. SRItransition ( SRIT)– where a few principles of SRI were applied in combination with modified or existing conventional practices by farmers. The word “ transition” was used because the practices are generally transitioning toward SRI with different degrees of SRI adoption and types. These practices do not fall in either category of SRI or FP. Instead, these practices were modified by farmers, improved and considered better than FP. These plots were also termed as “ learning plots”. Details of the experiment along with the specific details of the SRID or SRI, SRIT and CP alternatives can be seen in Mishra etal. ( 2021). Aligned with the Farmer Field School ( FFS) interventions, FPAR structure and research/ outreach implementation design was established ( Figure5.3). At some places, the structure was adapted based on the existing local government extension department’s program implementation structure and also according to the farmer’s needs and requirements. The design involved 50% women ( at least) and 10% landless to have an inclusive intervention. This structure facilitated the systematic introduction of SRI/ IPM/ FFS approaches for the development of knowledgeintensive and locationspecific technologies by bringing farmers, researchers, trainers and other stakeholders 4th post FFS site (2 FT) 3rdpost FFS site (2 FT) 2ndpost FFS site (2 FT) 1stpost FFS site (2 FT) 4th post FFS site (2 FT) 3rdpost FFS site (2 FT) 2ndpost FFS site (2 FT) 1stpost FFS site (2 FT) 4th post FFS site (2 FT) 3rdpost FFS site (2 FT) 2ndpost FFS site (2 FT) 1stpost FFS site (2 FT) FPAR sites FPAR sites FPAR sites Figure5.3 Structural diagram of CFPAR and FPAR in one province. 96 Abha Mishra et al. together, and by fueling their innovative capacity. Apart from these tangible and quantifiable direct benefits to the target groups of farmers, locally developed technologies for rice and other crops could take a horizontal spread pathway and reach other farmers in neighboring communities ( approx. 50,000 farmers, based on past FFS experience in the region) through field days. Through this learningcentered approach, we also refined the curricula options for women and landless in order to capitalize on the opportunity that the action presented for furthering the leadership and empowerment of women, especially in household decisionmaking and income generation activities. The process of engagement led to the development of informal farmers’ groups and networks in all four countries. The FFS interventions also facilitated systematic data collection. The data were compiled at provincial, at country and, finally, at regional level using online project database ( see User’s guideline for online database: http:// srilmb.ait.asia/ downloads/ User’s%20guide%20on%20online%20database%20for% 20SRILMB.pdf). Furthermore, the structure helped in creating a way forward for participatory policy and program development for ensuring better market access, price and returns, also as a step toward NDCs contribution under the Paris Agreement along with achieving its SDGs. The research conducted on the policy environment, and the institutional responses to the adaptation, revealed that the adaptation and adoption of agroecological practices like SRI in the region need to be further strengthened realizing that the macroeconomic situation across LMB countries is at different stages of development, and still evolving ( done by Oxfam and compiled in Mishra, 2019b). Nevertheless, the results of this collaborative engagements showed that SRI principleled practices helped to improve conditions in rainfed areas across the LMB region in numerous ways: average rice yield increased by 52%, and net onfarm economic returns were raised by 70% because of lower production costs. Labor productivity was increased by 64%, water productivity by 61% and the efficiency of mineral fertilizer use rose by 163%. The total energy input required for farming operations was decreased by 34% per hectare ( Mishra etal., 2021). The data also showed that per hectare emissions of GHG were significantly reduced, by 14% with irrigated rice production, and by 17% from a lower level in rainfed cropping ( Mishra etal., 2021, Table5.1) due to less input usages. In terms of average reduction in GHG emissions from SRI fields in the three countries ( Thailand, Vietnam and Laos), it was 25% from irrigated and 30% from rainfed systems. Therefore, the ecoefficiency ( Ecoefficiency ( USD/ tCO2 eq/ ha/ year) = Net income ( USD)/ Total GHG emissions ( tCO2 eq/ ha/ year)) was also increased under SRI and SRIT practices compared to the baseline. Interestingly, when the ecoefficiency of rainfed and irrigated production systems was compared, it was found that rainfed production was more ecoefficient compared to irrigated systems ( Figure5.4). These findings were based on the general biophysical properties of the production environment where trials were conducted and on the cropping pattern followed in those areas ( for details see Mishra etal., 2021). If we look across the four countries, 64% area is rainfed ( 74.1% in Thailand, 83.7% in Cambodia, 41.1% in Vietnam and 81% in Laos), and only 36% System of rice intensification 97 is irrigated in the region. Using the data from our research findings to calculate the GHG emissions from current conventional practice for the LMB region as a whole, it was estimated to be 6.41 million tCO2eq from rainfed and 5.18 million tCO2eq from the irrigated regions of the four countries. With adoption of SRID methods, the GHG emission will be 5.13 million tCO2eq from rainfed and 4.11 million tCO2eq from irrigated rice areas, which is an overall reduction of 20% ( Figure5.5). 350.0 300.0 250.0 200.0 150.0 100.0 50.0 127.9 140.4 114.4 128.1 90.4 101.4 268.0 287.0 0.0 TH-IRTH-RF CA-IRCA-RF VTM-IRVTM-RFLAO-IRLAO-RF Eco efficiency (USD/tC O2eq/ha/year) Eco-efficiency (USD/tCO2eq/ha/year) Figure5.4 Average ecoefficiency of irrigated and rainfed production systems with SRI practices in LMB countries. Table5.1 Greenhouse gas ( GHG) emission ( tCO2eq/ ha) from SRI and conventional fields Countries Irrigated Rainfed SRI Baseline % change with respect to baseline SRI Baseline % change with respect to baseline Thailand 1.86 2.52 −26 1.42 2.07 −31 Vietnam 2.35 2.92 −20 1.9 2.48 −23 Laos 1.17 1.74 −33 0.73 1.3 −44 Cambodia 2.20 1.54 42 1.76 1.09 61 Regional ( av. of four countries) 1.89 2.18 −13 1.45 1.74 −16.67 Regional ( av. of three countries: Thailand, Vietnam and Laos) 1.79 2.39 −25.1 1.35 1.95 30.76 Source: Based on authors’ own data from field. 104 Abha Mishra et al. Ketelaar, J.W., MoralesAbubakar, A.L., Van Du, P., Widyastama, C., Phasouysaingam, A., Binamira, J. and Dung, N.T. ( 2018) ‘ Save and Grow: Translating policy advice into field action for sustainable intensification of rice production’, In: Agricultural Development and Sustainable Intensification: Technology and Policy challenges in the face of Climate Change. London: Earthscan, p p. 23– 51. 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The International Bank for Reconstruction and Development and World Bank. Thakur, A.K. and Uphoff, N.T. ( 2017) ‘ How the system of rice intensification can contribute to climatesmart agriculture’, Agronomy Journal, vol 109, p p. 1163– 1183. Thakur, A.K., Mandal, K.G., Mohanty, R.K. and Uphoff, N.T. ( 2021) ‘ How agroecological rice intensification can assist in reaching the Sustainable Development Goals’. Available at: https:// doi.org/ 10.1080/ 14735903.2021.1925462 United Nations Environmental Programme ( 2021). ‘ Making peace with nature. A scientific blue print to tackle the climate, biodiversity and pollution emergencies’. Available at: https:// www.unep.org/ resources/ makingpeacenature United Nations Environmental Programme& Climate and Clean Air Coalition ( 2021) ‘ Global methane assessment: Benefits and costs of mitigating methane emissions’. Available at: Methane|Climate& Clean Air Coalition ( ccacoalition.org)& Global Methane Assessment: Benefits and Costs of Mitigating Methane Emissions| UNEP– UN Environment Programme. Wang, X.T. and Below, F.E. ( 1996) ‘ Cytokinins in enhanced growth and tillering of wheat induced by mixed nitrogen source’, Crop Science, vol. 36, p p. 121– 126. Whitten, M.J. and Settle, W.H. ( 1998) ‘ The Role of the Smallscale Farmer in Preserving the Link between Biodiversity and Sustainable Agriculture’, p. 187– 207, In: Chou, C.H. and Shao, K.- T. ( Eds.), Frontiers in Biology: The Challenges of Biodiversity, Biotechnology and Sustainable Agriculture Proceedings of 26th AGM, International Union of Biological Sciences, Taiwan 17– 23 November 1997, Academia Sinica, Taipei 1998. World Economic Forum ( WEF) ( 2021) ‘ The Global Risks Report 2021’, 16th Edition, World Economic Forum, ISBN: 9782940631247, Available at: https:// www3.weforum. org/ docs/ WEF_The_Global_Risks_Report_2021.pdf DOI: 10.4324/9781003273172-6 Introduction Rice ( Oryza sativa L.) is one of the principal staple food crops, which ensures food and nutritional security to a large percent of the global population, especially in Asia. It is cultivated globally by more than 95 countries and occupies 11% of the world’s arable land with an annual production of about 678 million tons ( https:// www.statista.com). Thus, rice is an important cereal crop on which global food security is dependent. The three major rice producing countries are China followed by India and Indonesia, which are also the three of the most populated countries. To satisfy the global food demand, food production needs to be increased by 70% by 2050 ( Muthayya etal., 2014). The changing trend of farming and other land uses has decreased the availability of arable land for rice farming that limits further expansion of rice cultivation. Thus, increasing the rice productivity through intensification is one option to meet the growing demand for rice production. However, the intensification must be done in a sustainable manner with minimum environmental impacts ( FAO, 2011, 2014, 2016). We need to learn from the past experiences, and any future strategy to increase rice production must be performed without further increasing greenhouse gas ( GHG) emissions, particularly methane and nitrous oxide. Conventionally, rice is grown by puddling the rice fields and transplanting the seedlings in the puddled land. The main advantage of this system includes increased nutrient mobility due to the continuous presence of standing water in the field, weed suppression and a stable yield. However, the anticipated climate change will negatively affect the precipitation pattern and crop water requirement, which in turn will affect the timely availability of irrigation water for sustaining rice production ( IPCC, 2007). In Asia, anticipated water crisis is reported to be the root cause of ‘ physical water scarcity’ for nearly 39 million ha of irrigated rice by 2025 ( Tuong and Bouman, 2003). This would ultimately result in 30% decline in agricultural production by 2050 ( Hossain and Siddique, 2015). Moreover, the presence of standing water in the traditional lowland paddy fields causes arsenic toxicity and emits significant amount of methane gas, which contributes to global 6 Direct seeded rice A potential climateneutral and resilient farming system Anjani Kumar, Amaresh Kumar Nayak, Mehreteab Tesfai, Rahul Tripathi, Sangita Mohanty, Shyamaranjan Das Mohapatra, Kiran Mohapatra and Udaya Sekhar Nagothu Direct seeded rice 107 warming ( Kumar etal., 2016). The other challenge is the migration of labour force from rural to urban areas, as a result of which the availability of labour for agricultural work is at stake in most parts of South and Southeast Asia. Thus, rice cultivation is faced by two risks in Asia mainly from anticipated irrigation water scarcity due to climate change and variability and increased labour costs ( Pandey and Velasco, 2005). In addition, there are other constraints including the availability of seeds and timely extension services support. Thus, rice demands continuous efforts to ensure a resourceefficient sustainable alternative system to cope with the vagaries of climate change and other growing risks. A viable alternative rice establishment technology, which can produce more grain with less labour and ensure optimal water use in an ecofriendly manner, would potentially be direct seeded rice ( DSR). The main objective of this chapter is to assess the performance of DSR compared to conventional puddled and transplanted rice, and further recommend strategies that can promote adoption and scaling up of DSR as a potential climateneutral and resilient rice farming system ( CNRFS). The chapter was arranged as follows: first, the introduction section that described the main challenges of rice production, followed by the principles and practices of DSR, its advantages and limitations. Then, the performance of DSR compared to conventional puddled and transplanted rice was assessed using evidencebased field data from India and other countries under both dry and wet conditions. The performance indicators that were evaluated included grain yield, nutrient and water use, GHG emissions and socioeconomic benefits. Finally, the chapter recommended strategies to promote adoption and scaling up DSR. Direct seeded rice Direct seeded rice ( DSR) is an establishment technique in which seeds are sown directly in the main field rather than by transplanting seedlings from the nursery. This technique has several advantages; however, there are some challenges that limit the adoption of DSR ( Table6.1). The main challenges include high weed infestation, rootknot nematode infestation, nutrient deficiency ( e.g., Bui etal., 2021) and relatively lower grain yield compared to conventional transplanted rice. Some of these problems can be effectively handled by following integrated approaches of nutrient, pest and weed management. Methods of direct seeded rice The main methods of DSR are dryDSR, wetDSR and water seeding ( Figure6.1). i DSR with dry seeding ( dryDSR): The practice of dry seeding involves sowing of seeds in the field with optimum moisture conditions. Seeds are sown with presowing irrigation to enhance a good seed germination rate and establishment before the onset of monsoons. This practice ensures timely crop establishment, which ensures higher productivity; in addition, it is less demanding in labour, water and energy compared to conventional paddy transplantation. 108 Anjani Kumar et al. ii DSR with wet seeding ( wetDSR): The main agronomic practices involved in wet seeding are the sowing of sprouted seeds ( seed rate = 50 kg ha−1) on the puddled bed with the help of drum seeder. The advantages of this method include reduction in labour costs and drudgery, besides, timely and better crop establishment ( De Datta, 1986). The prerequisites for successful wetseeded rice are carefully levelled field and effective weed control ( Balasubramanian and Hill, 2002). iii Water seeding: Water seeding is mostly practised in irrigated lowlands where standing water of 5– 15 cm is present. In this practice, land is dry ploughed, harrowed but puddling is avoided after dry tillage. Pregerminated seeds are broadcast in the standing water of 10– 15 cm depth; however, after wet tillage, puddling is practised. Dry direct seeded rice in upland Dry direct seeded rice in lowland Dry direct seeded rice in medium and shallow lowland Wet direct seeded rice in dry season Wet direct seeded rice in wet season Water seeding after dry tillage Wet seeding after wet tillage Dry direct seeded rice Wet direct seeded rice Water seeding Direct seeded Rice Figure6.1 Different methods of DSR and its suitability in different rice ecologies. Table6.1 Main advantages and disadvantages of DSR compared to transplanted puddled rice ( TPR) Advantages of DSR References • Saves irrigation water use by 30– 50% and increases water productivity, if properly managed Kumar etal. ( 2019) Field study ( Figure6.4) • Reduces GHG emissions ( mostly methane) Singh etal. ( 2005) • Saves labour requirement up to 60% ( no transplanting, puddling and maintenance of standing water), thus reduces labour cost and renders higher net profit Kumar and Ladha ( 2011) Field study ( Figure6.6) • Maintains soil aggregates, reduces percolation losses, avoids formation of hard pans in the root zone and ensures favourable soil condition for succeeding crops Sharma etal. ( 2003) Disadvantages of DSR • Weed emergence in DSR puts a strong competition for nutrients, moisture, space and light, and results in reduction of economic yield Bista and Dahal ( 2018) • Nutrient uptake by rice roots under DSR is decreased due to change in nutrient dynamics, compared to TPR Johnson etal. ( 2005) • Higher occurrence of rootknot nematode which results in severe damage to rice in all ecologies Prot etal. ( 1994) Direct seeded rice 109 In the following section, the performance of DSR was compared to conventional transplanted rice ( TPR). The assessment was performed using some key indicators including grain yield, water input and water use efficiency, nutrient use, GHG emissions, farm mechanization and benefitcost ratio of DSR. The results were discussed using the research findings from various studies conducted in different rice growing areas of India and other parts of Asia, under both dry and wet conditions. The data from the Government of Norwayfunded Resilience project ( www.resilienceindia. org) focusing on climatesmart rice production systems ( 2018– 2022) were analysed to show the performance of DSR in Cuttack district, Odisha state of India. Performance of DSR i Grain yield: Performance of DSR in terms of grain yield is dependent on many factors such as climatic condition, crop establishment, precise management of inputs ( irrigation water and nutrients), crop lodging and stakeholder’s knowledge ( e.g., efficient use of machinery) on different farm operations ( Rao etal., 2007). Pilot demonstrations conducted under the Resilience project in Cuttack , Odisha ( 2018– 2022) showed that grain yields of wetDSR and dryDSR were significantly higher than the TPR. The rice yield in DSR increased by 6. 71– 13.3% in the wet season and by 6. 45– 11.5% in the dry season compared to TPR. This contrasts with a study conducted by Kumar and Ladha ( 2011) that showed reduction ( 9– 28%) in grain yield under dryDSR compared to conventional TPR. This may be due to different agroecological settings in which the two studies were carried out. Grain yield under different crop establishment methods is summarized in Figure6.2. In general, the grain yield under DSR varied from 3 t ha−1 ( Farooq etal., 2009) to nearly 6 t ha−1 ( Sharma etal., 2004). In most of the studies, 0 1 2 3 4 5 6 TPRDSR TPRDSR TPRDSR TPRDSR TPRDSR TPRDSR TPRDSR D-DSRW-DSR TPR Harada et al., 2007 Mitchell et al., 2004 Farooq et al., 2009 Hobbs et al., 2002 Sharma et al., 2004 Ko and Kang, 2000 Sarkar et al., 2003 Resilience project t ha-1 Grain Yield Figure6.2 Rice grain yield under different crop establishment methods. 110 Anjani Kumar et al. the grain yield under DSR was higher than under TPR except in one study reported by Farooq etal. ( 2009). One of the reasons for the better performance of DSR was probably the desirable traits ( Table6.2) of the improved rice cultivars used and the good agronomic practices applied. ii Water input and water use efficiency: One of the critical factors for high water productivity in dry and wet seeded rice is precision water management. Maintaining aerobic conditions in the field is essential for promising crop stand establishment and high seedling vigour in early stages of dry seeding, whereas in wet seeded rice, precision water management is required for better performance of the applied herbicides and crop growth. Several studies were carried out during the last two decades, analysing the performance of water productivity and water savings under different rice systems. The research findings on total water inputs in rice under the different water management methods are summarized in Figure6.3. The total water input ranged from about 3,500 mm under flooded and transplanted ( Kato etal., 2009) to 500 mm under alternately submerged/ nonsubmerged conditions ( Belder etal., 2004) under different rice ecologies. The total water input under DDSR, WDSR in the Resilience project was lower than 1,000 mm except in TPR. Experiments conducted under the Resilience India project reported that water saving was higher by 18– 19.5% in wetDSR and by 43– 45% in dryDSR over TPR ( Figure6.4). Similar findings were reported by Sharma etal. ( 2002) that observed 12– 60% water savings under DSR and 13– 30% under TPR. However, the water productivity under DSR in dry conditions ( 0. 4– 0.5 kg m−3) was higher than that under DSR in wet conditions TPR ( 0. 2– 0.3 kg m−3) ( Figure6.2). The water productivity can further be increased under DSR by precise land levelling using laser land leveller. This ensures uniform distribution of water, proper seed germination and weed control and good crop establishment, resulting in higher yield ( 7– 24%) and irrigation water saving by 12– 21% ( Choudhary etal., 2002). In DSR, precision irrigation practices like microirrigation, drip irrigation and other automated irrigation technologies can be used for enhancing water use efficiency. However, this requires additional investments that Table6.2 Desirable traits of rice cultivars suitable for DSR Desirable traits for DSR References • Lodging resistance Mackill etal. ( 1996) • Early seedling vigour for weed competitiveness Zhao etal. ( 2006) • Vigorous root system for better anchorage and soil moisture extraction Pantuwan etal. ( 2002) • Anaerobic germination Ismail etal. ( 2009) • Rapid shoot and root growth Cui etal. ( 2002) • Shorter duration of the crop Dingkuhn etal. ( 1991) • High crop growth rate during the reproductive phase Kato etal. ( 2009) Direct seeded rice 111 smallholders cannot afford unless they are supported by subsidies from the government and maintenance of equipment. The Government of India has initiated countrywide programmes for upscaling precision irrigation systems for fruit crops, which may be eventually extended to rice ( Agricoop, 2021). Drip and sprinkler irrigation technologies were found effective in saving irrigation water in rice up to 67%, and two-fold increase in the yield ( Arns, 1999). Other advanced studies have shown that the application of artificial intelligence in automation of drip and sprinkler irrigation systems can further 0 500 1000 1500 2000 2500 3000 3500 4000 CF ASNS CF AWD TPR RB20 CF AWD FLTP ARDS CF AWD (0.2 bar) Daily irrigation AWD (40 kPa) CF AWD (30 kPa) CF AWD (30 kPa) D-DSR W-DSR TPR Beldar et al., 2004 Beldar et al., 2005 Choudhary et al., 2007 Matsuo et al., 2009 Kato et al., 2009 Ghosh et al, 2010 Yadav et al., 2011 Kadiyala et al., 2012 Kumar et al., 2017 Resilience project Water input (mm) Figure6.3 Representative studies reporting total water input in rice under different water regimes. 0 0.1 0.2 0.3 0.4 0.5 0.6 WDSR DDSR TPR Water Productivity kg kg-3 WS DS Figure6.4 Comparison of cost of production and benefitcost ratio under DSR and TPR. 112 Anjani Kumar et al. improve the application efficiency over surface irrigation method ( Bhoi etal., 2021). However, drip and sprinkler methods are not commonly practised by farmers in the rice growing countries, due to difficulties in maintenance and initial establishment costs. At the same time, we are observing a shift towards adoption of sensorbased technologies for sitespecific and needbased application of irrigation water in India and other regions within the agriculture sector. Some of the sensorbased technologies used for scheduling irrigation include gypsum block sensor, timedomain reflectometry ( TDR), frequencydomain reflectometry ( FDR) and neutron probe sensors. Recently developed advancement in precision irrigation management is the development of Customized ColourCoded Tensiometer ( Kumar etal., 2021a) and the NRRI ARM sensor ( Kumar etal., 2021b). Some of these sensors are being made farmer friendly and easy to handle and have the potential to save irrigation water, which can be up to 41% without any significant decline in the grain yield ( Kumar etal., 2021a,b). iii Integrated nutrient and fertilizer management: Sitespecific or precision nutrient management is becoming important in rice and other cropping systems to improve productivity ( Dobermann and Witt, 2004; Sapkota etal., 2016). This will not only reduce overuse of fertilizers but also reduce GHGs significantly. Proper dosage, and right time and method of application play an important role in nutrient management in rice. Otherwise, it can lead to losses of reactive nitrogen ( N) through denitrification, volatilization and leaching, as observed under dryDSR, which is higher compared to TPR ( Davidson, 1991). As a result, the availability of plant nutrients such as nitrogen ( N),phosphorus ( P), potassium (K), sulphur ( S), iron ( Fe) and zinc ( Zn) also reduced ( Ponnamperuma, 1972), which hinders optimum plant growth and yield under DSR. There are several fertilizer management practices that can contribute to an improvement in the nutrient availability in DSR. a Split fertilizer application: The dose of N fertilization used in DSR is higher than that used in TPR to compensate the higher losses of reactive N ( Gathala etal., 2011). Normally, under DSR, onethird of the full dose of N, P and K is applied as basal dose, which enhances the fertilizer use efficiency by facilitating the availability of nutrients to the plants. The remaining twothirds dosage of N is applied in equal splits at vegetative ( active tillering) and reproductive ( panicle initiation) stages ( Kamboj etal., 2012). Such type of fertilizer application increases the grain yield and maximizes N use efficiency. More details about the dosage and timing of fertilizer application for DSR in different agroecological settings are provided in Box 6.1. Awareness about the fertilizer management suitable to DSR needs to be increased among farmers through regular trainings and information. b Green/ brown manuring: In conventionally tilled DSR, the use of chemical N fertilizer can be significantly reduced by applying green/ brown manuring such as Sesbania ( Farooq etal. 2021). The seeds of Sesbania spp Direct seeded rice 113 Box 6.1 Nutrient management recommendations for dryDSR under different agroecological settings a Upland rice: Welldecomposed farmyard manure or cow dung @ 2t acre−1 should be applied at the time of final land preparation, followed by a blanket dose of 24:12:12 kg of N:P:K acre−1. For broadcast crop, the full dose of P and K during the final land preparation should be applied, and 75% of N after the first intercultural operation and rest 25% N at the panicle initiation ( PI) stage. For line sown crops, 25% N + full P and K as basal dose and band placement is recommended and 50% N at three weeks after the first intercultural operation and rest 25% N at the PI stage. However, in sandy soils, K should be applied in two equal split doses ( 50% as basal and rest 50% at PI stage), whereas in acid soils, 50% P as SSP and rest 50% P through rock phosphate should be applied. Phosphorous solubilizing bacterial culture @ 25 g kg−1 is recommended to enhance availability of P in soil, whereas integration of 50% recommended dose fertilizer + Gliricidia @ 2.5 t ha−1 + Phosphate Solubilizing Bacteria @ 2.5 kg ha−1 + Azotobactor @ 2.5 kg ha−1 is recommended for autumn rice. b Deep water rice: Blanket recommended dose is N:P:K @ 16– 8– 8 kg acre−1. It is desirable to apply 8 kg P2O5 acre−1 during land preparation. The prevailing water regime does not allow application of nitrogenous fertilizer from late July to October. It is desirable to apply nitrogen fertilizer in one or two doses before water accumulates to depth of 5– 10 cm in the field. Usually, fertilizer is placed in bands at sowing with seedcumfertilizer drill, hand plough or behind the country plough. For higher nitrogen use efficiency, 8 kg N acre−1 as basal and rest 8 kg is applied before flooding. Source: Adapted from Saha etal. ( 2012). @ 19.76 kg ha−1 are broadcast three days after rice sowing and allowed to grow for 25– 30 days. It is then dried by spraying 2, 4D Ethyl Easter. In the case of broadcast rice, at the time of beushening ( a traditional system of rice cultivation common in rainfed regions), harvested Sesbania foliage is incorporated in soil, whereas in the case of line sowing the incorporation is done at the time of manual weeding. This practice supplies about 14 kg of N per acre1, adds organic matter to soil and helps in maintenance of overall soil health. Thus, a part of nitrogenous fertilizer ( up to 25%) can be replaced by brown manuring. The occurrence of nematode infestation in DSR can be minimized by growing summer legume crops such as green gram in ricewheat or green manuring of Crotolaria juncea L. c Fertilizer and seed treatment: One of the important factors in sustainable rice production is integrated nutrient management, to improve the availability 120 Anjani Kumar et al. to farm machineries to smallholders, women and youth. For example, the Resilience project established a Custom Hiring Centre ( CHC) in Assam ( Golgahat district) to support farmers to provide farm machineries such as power tillers, paddy threshers, straw choppers, power weeders and winnowers at a subsidized hiring rate. The rent charge is used to cover the costs of maintenance and operation of CHC and the machineries. According to farmers, the timely availability of farm machinery has enabled them to perform the different farming activities efficiently. v Lack of awareness on DSR cultivation methods: The virtual and/ or physical Village Knowledge Centre ( VKC) services ( ICTbased digital tools) introduced in the Resilience project have increased farmers’ awareness about DSR. Participatory extension services through VKCs and farmertofarmer learning have encouraged other farmers to practise DSR. The VKCs extension personnel working in collaboration with the staterun farmer training centres ( KVKs) is helping in scaling up DSR. Policy and institutional support for upscaling DSR Extension activities can play a very important role in popularization of DSR, which includes training, demonstration of DSR in farmer’s field, farmertofarmer learning, onfarm trials related to various potential problems faced by farmers and exposure visit of farmers to demo farms. In this regard, there are several opportunities at international, national and state levels that can enhance upscaling DSR practice in suitable rice ecologies. Recent IPCC reports and other climate action initiatives globally are promoting DSR as one of the most promising climateneutral farming systems ( Sulaiman etal., 2018). India is committed to fight the challenge of climate change considering CoP26 commitments. One of strategies/ pathways prioritized in the policy agenda is to make Indian agriculture resilient and sustainable in a changing climate. DSR is having the potential for reducing GHG emission and is being included in the national missions that can help in achieving the target of netzero emissions by 2070, which India has pledged as per the CoP26 at Glasgow, Scotland ( Padhee and Whitbread, 2022). DSR has been prescribed as efficient in terms of input use like water, labour and energy when compared to traditionally perceived waterguzzling crop like paddy. In this regard, one of the salient recommendations that emerged during the First Indian Rice Congress held in December, 2020 in India recognized the potential of DSR as one of the promising climateneutral and sustainable rice production option ( Nayak etal., 2020). Some states in India such as Punjab are targeting to bring 1 million ha rice cultivation under DSR technique. Efforts are underway in upscaling CSA technologies that include DSR with the support of KVKs and other stakeholders outside the project areas. Direct seeded rice 121 Conclusions This chapter analysed the performance of DSR on grain yield, nutrient management, water use, GHG emissions and socioeconomic benefits and compared the results with TPR under different rice ecologies. DSR can be a viable alternative rice system to address the future challenges in the drier and warmer climate scenarios, provided enabling policy and institutional support are in place. In general: • DSR is promising as it overcomes the problem of labour and water scarcity. • Adoption of DSR will benefit not only commercial farmers but also smallholders • DSR reduces agricultural workload and provides women and youth the opportunity to move into more remunerative onfarm and offfarm employment. • Further, application of modern biotechnology and development of effective crop, water and soil management practices has the potential to optimize crop yields under DSR. • DSR can curtail methane emissions by 44%, and the cumulative GWP by 25% compared to TPR if properly managed. A coordinated effort is needed to promote adoption and upscaling of DSR. In this regard, researchers must focus on developing rice varieties that have early vigour, robust root architecture and weed competitiveness during early stages of crop growth. Extension workers must increase demonstrations and training farmers and other stakeholders about the practices of DSR and its benefits. Policy makers and government agencies should support the uptake and promotion of DSR practice in the rice farming systems through investments and marketing support measures. Finally, farmers practising DSR should be compensated for their contribution to reduce GHG emissions. Acknowledgements The chapter has benefited from the results of the Resilience project field trials in the Odisha state of India. The authors would like to thank field enumerators and lead farmers involved in the field demos. At the same time, they acknowledge the support of the Norwegian Ministry of Foreign Affairs/ The Norwegian Embassy, New Delhi for funding and support to the Resilience project in India ( 2018– 2023). References Agricoop ( 2021) ‘ Annual report, 2020– 2021’. 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DOI: 10.4324/9781003273172-7 Introduction In Europe, rice cultivation in terms of area and production has been stable between 1994 and 2020. The amount of rice produced in 2019 was about 2.8 million tonnes from a total cultivated area of about 428,000 ha, which represented 0.27% of world’s rice production and 0.41% of world’s harvested area ( FAOSTAT, 2019). Due to temperature and water needs, rice in Europe is only cultivated in southern regions and in specific areas or districts, mainly in Italy ( 53.2% of total area as of 2020) and Spain ( 23.9%), and to a lesser extent in Greece ( 8.4%), Portugal ( 6.2%), France ( 3.6%), Bulgaria ( 2.9%), Romania ( 1.4%) and Hungary ( 0.7%). The production provides nearly 60% of internal rice consumption needs in Europe; the remainder 40% ( approximately 1.2 million tonnes of milled rice per year, mainly Indica/ long grain rice) is imported, especially from Pakistan, Thailand, Myanmar and Cambodia ( EC, 2019a). Though the rice production in the European Union ( EU) is comparatively smaller to the total global production, the rice farming systems in some of the European regions have a long tradition and have important economic, cultural and landscape relevance at local and regional scale. The current research on improving sustainability and carbon neutrality of rice farming in Europe can therefore be useful to other rice growing regions in the world. This is one of the main reasons for including this chapter in the book. In the EU, rice is normally cultivated under flooding conditions, sown in spring and harvested in autumn. Average yields range between 4 and 8 tonnes per hectare, also depending on cultivars that mostly belong to Japonica rice varieties. Flooded paddy landscapes providing habitats for many organisms including migratory birds are important for biodiversity conservation and artificial wetland maintenance in Europe. This agroecosystem is similar to other rice growing regions, where several environmental problems can be observed due to high use of fertilizers and agrochemicals, leading not only to pollution of soil and water but also to greenhouse gas ( GHG) emissions ( Kraehmer etal., 2017). Moreover, climate change ( CC) further increases the vulnerability of these specialized farming systems due to the rise in water shortage, new pests and diseases and soil salinity in coastal regions. 7 Carbonneutral farming solutions in rice farming systems in Europe Stefano Monaco, Patrizia Borsotto, Roberto Cagliero, Chiara Bertora, Omedé Gabriele, Maite MartínezEixarch and Laura Bardi 128 Stefano Monaco et al. GHG emissions from agriculture and rice farming systems in the EU Considering all sources and sectors, except for LULUCF,1 the total GHG emissions decreased by about onethird in EU since 1990. A total of 3.6 Gt of CO2 eq emissions was estimated in 2019 ( EEA, 2019), which is about 10% of the global GHG emissions ( UNFCCC, 2019). According to the EEA, this is mainly due to the implementation of the EU and national policies and measures that have contributed to the decrease of GHG emissions in almost all sectors, particularly in energy supply, industry and the residential sector, while emissions from agriculture have increased in recent years. The EU has set new targets of 55% reduction by 2030 compared with 1990 level and of achieving a climateneutral economy by 2050, which will need substantial efforts across all the sectors of the economy. The agricultural sector has contributed to 12.7% of the total GHG emissions in 2019, mostly methane ( CH4) and nitrous oxide ( N2O) ( EEA, 2019). The shares of CH4 and NO2 emitted from the agricultural sector are highly relevant in the EU, because they correspond to 53.7% and 74.6% of total CH4 and NO2 emissions, respectively. Although rice in the EU is usually cultivated under flooded conditions, which causes high amount of CH4 emissions during crop growing season at field scale, the contribution of CH4 from paddy fields to the total CH4 emissions is only 1.2%, due to the very limited area of rice cultivation, while the main sources are represented by ruminants’ enteric fermentation ( 80.7%) and manure management ( 17.4%). Nevertheless, as the contribution of CH4 emissions from rice paddies to global warming is relevant at global scale, the effort for its reduction concerns the entire global community, as recognized by the EU in its strategy to reduce methane emissions ( EC, 2020). Concerning N2O emissions, the direct and indirect N2O emissions from agricultural soils are relevant, representing 88.6% of the sector in 2019, while the remaining share originates from manure management ( 11.2%). Policies on climate impacts or rice assume that N2O emissions from this crop are negligible or very small, in fact, less than 10% of the total emissions, and none of the rice growing countries include them in their national inventories. Nevertheless, watersaving techniques, which have been developed and spread to reduce water use and CH4 emissions from paddies, may increase N2O emissions through aerobicanaerobic cycling, which favours nitrification and less complete denitrification. A more detailed account of the aerobicanaerobic cycling and its impact on N2O emissions is given in Chapter3. Besides the information on the contribution of the agriculture and rice sector to climate change through IPCCsupported national GHG inventory methodology, several other methods have been proposed for calculating the magnitude of impact per kilogram of food products and for understanding where the impacts are concentrated within the production chain from field to supermarket. Life cycle assessment ( LCA) is the most utilized method for evaluating the environmental impacts of processes and products through indicators such as global warming potential ( GWP) and carbon footprint. In an LCA study carried out in the Vercelli district, which is one of the most important rice producing area Carbon-neutral farming solutions in rice farming systems 129 in Northern Italy, Blengini and Busto ( 2009) estimated that in the baseline rice farming system, direct emissions from the field were the first source of GWP with 68% of contribution, followed by fertilizer production ( 9%) and product transportation ( 6%). They also investigated the effects of alternative rice farming systems such as organic farming and watersaving techniques that provided interesting results. For organic farming, a lower impact per hectare but a higher GWP per unit mass of product was assessed, which increased by 20%, as expected due to lower yields. As organic farming has other important beneficial effects, such as biodiversity conservation and environmental pollution reduction, which are also major concerns in large rice producing regions of Asia, the research strategies for maintaining high yield and low GWP per product in the organic rice system have become more important in recent years. The use of alternatives such as watersaving techniques, which could also cause yield reductions and even concerns about its feasibility and negative tradeoffs at large scale, has nonetheless the potential to decrease GWP by about 50%. EU policy aspects and economics drivers Climate action is one of the EU’s key priorities and at the heart of European Green Deal initiative ( EC, 2019b). Climate and energy are one of the five fields of action to which the EU has assigned specific objectives to be achieved within the framework of the Europe 2030 strategy, the aim of which is to fill the gaps in the EU growth model, thus creating the conditions for smart, sustainable and inclusive growth. The EU pursues these objectives through a combination of programmes and financial support measures, including the European Structural and Investment Funds, contributing to the thematic objectives of supporting the transition to a climateneutral economy in all sectors and promoting climate change adaptation, risk prevention and management. Concerning the agricultural sector, a stronger focus on green issues is one of the main emphases through innovations of the future Common Agricultural Policy ( CAP), and it was already implemented partially in the 2014– 2020 programming period ( Matthew, 2012). Under the first pillar, direct payments were subject to crosscompliance, i.e. the observance of constraints aimed at environmental protection, food safety, animal welfare and the maintenance of land in good condition, in addition to commitments to the socalled “ green payment” or greening. Under the second pillar there was specific support for those farmers who, voluntarily exceeding the baseline of crosscompliance and greening, decided to adopt more sustainable production practices on the farm. Besides CAP, the organization of the Rural Development Programmes ( RDP) foresees that resources are concentrated on several measures in order to achieve synergistically certain common strategic priorities. It was possible to highlight Priority 5 that aims at “ Promoting resource efficiency and the shift to a lowcarbon and climate resilient economy in the agrifood and forestry sector”. This broader policy priority was broken down into five specific areas of intervention, which are known as Focus Areas ( FAs).