Product Line 3.4. Increasing resilience to climate change and reducing global warming potential
Rice production simultaneously contributes to global climate change and is affected by it. Currently, irrigated double- and triple-cropping rice systems are a significant source of methane and a small source of nitrous oxide. But, flooded rice fields also sequester and store large amounts of soil carbon, which would be emitted as atmospheric CO2 in case of an unsustainable conversion to upland systems. Management of water, soil organic matter, and nutrients can be changed to minimize these contributions to global warming. Reduced soil tillage not only affects organic matter or water availability but also can further reduce fossil fuel consumption. Global climate change will have profound effects on the livelihood of rice farmers as well as on rice production. Crop yield losses may increase because of rising air temperature or more frequent occurrence of extreme heat, drought, or storms. Because of these drivers of change, farm management practices will change. Already, two major trends are emerging rapidly in the intensive rice systems of Asia: (1) changes in management of the rice crop and (2) changes in cropping systems, particularly diversification from double or triple rice monoculture to rice–upland crop systems such as rice-maize, rice-wheat, and rice-wheat-legumes. Systems that traditionally have been flooded for long periods of the year will be exposed to greater soil aeration. These trends will occur simultaneously and they will lead to significant changes in the cycling of energy, water, carbon, nitrogen, and other elements of paddy fields. There will be impacts on C and N budgets through changes in net fluxes of greenhouse gases (CO2, N2O, CH4) and reactive nitrogen compounds, on local and regional water budgets, on the sustainability of rice production systems over the long run (e.g., conservation vs. loss of soil organic matter), and on heat fluxes and associated climate-change processes (systems that use less water are likely to have increased soil and canopy temperatures).
The flora and fauna and behavior of weeds, insects, and plant diseases will change in direct response to changing climate and in indirect response to changes in management practices. The resilience of rice ecosystems, which is threatened in some intensive rice production systems already, will be further affected by these changes. For example, massive outbreaks of planthoppers have been reported in intensive rice areas in Thailand, Vietnam, Indonesia, and China, with associated increases in hopper-transmitted viral diseases. In Africa, the major challenge will be maintaining high production with less available water and selecting varieties that can cope with extreme temperatures. Other challenges are the effects of climate change on the distribution, virulence, and socioeconomic impact of pests, weeds, and diseases. The underlying processes of climate change and its induced short- and long-term impacts must be understood to formulate appropriate mitigation and adaptive strategies and policies. Governments need to develop policies to respond to climate change and transform the agricultural sector to protect farmers, consumers, agri-businesses, and natural resources.
The key question is how rice systems should be managed to be resilient and less vulnerable to high temperature and water shortages, to take advantage of rising atmospheric CO2 levels, and, at the same time, to emit fewer harmful greenhouse gases and remain profitable for farmers.
At new interdisciplinary “experimental platforms,” cropping systems “of the future” that respond to major drivers of change will be designed and tested. Detailed process-based science will quantify the fluxes and budgets of energy, greenhouse gases, and water in an unprecedented level of detail, for current and future scenarios. Models will be used to predict the trade-offs associated with crop/system improvements, and to design appropriate combinations of component technologies. For example, increasing water scarcity may increase crop temperature and thermal stress, further exacerbated by rising atmospheric CO2. Integrated solutions thus need to be targeted at specific climatic conditions and they will be different in semi-arid and humid tropical irrigated systems.
We will analyze and model crop microclimate and carbon and water balances in the rice canopy with respect to changing weather and soil water conditions. Upstream research will fill in knowledge gaps and weaknesses in current models, especially on (1) microclimate as influenced by the crop and plant-avoidance mechanisms of thermal stresses (e.g., thermal cooling and its trade-offs with water use), (2) the determinants of phenology, (3) temperature-induced respiration losses, and (4) the interaction of external factors such as temperature, CO2 concentration, and soil water content with crop growth and performance. Insights gained will be used to adapt management practices to mitigate global warming potential.
Adaptive research trials will be established in farmers’ fields with our research and extension partners, and will deliver concrete management recommendations and cropping system practices that both mitigate global warming and adapt to the impacts of climate change. We will investigate whether seasonal weather predictions can be generated and used through decision support systems to enable farmers to make strategic and tactical decisions about cropping system management. Epidemiological research will be conducted on major rice pests and diseases by elucidating the relationships among rice plants, diseases and their vectors, crop management practices, and the natural environment as determined by weather and hydrology. A global network for assessing crop health will be established with key partners. Weed species shifts in response to changes in hydrology (as induced by water scarcity) and crop management (e.g., shifts from transplanting to direct seeding) will be studied to identify intervention points for weed control. Principles to enhance ecological resilience against insect pests will be developed through ecological engineering and regionally targeted deployment of resistance genes in rice varieties.
3.4.1 Assessment tools (ecological resilience, impact of climate change, adaptive value of response options)
3.4.2 Field management technologies to reduce greenhouse gas emissions
3.4.3 Strategies to adapt to climate change and increase resilience
Advanced research institutes and universities are partners in the research on and development of new technologies and the underlying science. For example, a consortium of German institutions (from the Universities of Giessen, Bonn, and Bremen as well as Karlsruhe Institute of Technology, IMK-IFU, and Max Planck Institute, Marburg) are partners in the process-based research to measure and model the turnover and fluxes of carbon, nitrogen, and water in rice systems and to design mitigation options. We also closely collaborate with a range of international networks dealing with atmospheric processes, for example, FluxNet and AsiaFlux. JIRCAS and JAMSTEC in Japan will collaborate in the development of seasonal weather forecast models and integrate these into decision support systems for rainfed rice farming. Local adaptive research and dissemination/diffusion involve mainly research institutes and universities in the target countries, such as NAFRI in Laos; PhilRice in the Philippines; Can Tho University, Southern Institute for Water Resource Planning, and Cuu Long Rice Research Institute in Vietnam; and BARC, BARI, and BRRI in Bangladesh. At the same time, we perceive an increasing interest coming from the private sector to work jointly on adaptation and mitigation technologies.
Upstream science partners in the development of global health monitoring and ecological engineering tools to increase ecosystem resilience include other CGIAR centers, Charles Sturt University, University of Wisconsin, University of California-Davis, Embrapa and University of of Viçosa (Brazil), and ICAR institutes in India. A private-sector organization, Syngenta, is involved in management tool evaluation coordination, problem definition, and field surveys in target countries in Asia. Sites for experimental ecological engineering are established and maintained by the Chainat Rice Seed Center, Chainat (Thailand), Southern Regional Plant Protection Center and Plant Protection Department (Vietnam), and Zhejiang University and the Plant Protection Station, Jinhua, Zhejiang, China. In the area of systems approaches to adaptation to climate change, an informal consortium of crop scientists and modelers, operating since 2007, is intensifying its work at the interface of CRP 7 and GRiSP. Leading this consortium are scientists from IRRI, AfricaRice, Cirad, WUR, and NIAES. With support and leadership by Iran, a West and Central Asia rice research network will be established with focus on crop improvement and crop management solutions for adapting to climate change.
Research into strategies to cope with less available irrigation water includes IWMI and Agrymet. The effects of extreme temperatures are being evaluated with the help of Cirad and the University of Hohenheim, while the effects of climate change on the virulence of rice pests in Africa are being analyzed in collaboration with the University of Gottingen. With IITA, ICIPE, and the CGIAR Systemwide Program on IPM, Goettingen is also a partner in the proposal to use sustainable pest management strategies for mitigating the effects of climate change. The effects of climate change on the economic impact of parasitic weeds are being studied in close collaboration with WUR.
Users of information, tools, and mitigation and adaptive technologies will essentially include stakeholders (farmers, scientists, extension personnel, and policymakers) and the scientific community. Communication with farmers will engage a variety of means, including farmers’ direct involvement in field testing of technologies and participation in field days, farmers' fairs, and on-site workshops. We will also target local media that are accessible to farmers. Research outputs will be developed into simple extension materials and advisory notes that are culturally sensitive and easy to understand and these will be distributed through channels accessible to farmers.
We will take a multitiered approach to communication and dissemination, using different approaches to target different audiences. In the extension domain, including the relevant departments of extension (e.g., Cambodia, Laos) or appropriate NGOs (e.g., Bangladesh) in projects as core partners will be the general pathway by which technical guidelines and adaptation options will be mainstreamed into public- and private-sector extension services (e.g., the model being trialed by IDE in Cambodia) and thus channeled to farmers beyond those involved with the projects. This will require significant training activities to foster outreach to more extensionists within extension departments. Different training activities will be tailored toward the needs of immediate project partners, complemented by “training the trainer” approaches to reach out beyond the immediate extensionists involved in the projects. In countries such as Bangladesh, it is envisaged to involve various NGOs in annual technical workshops. In the policy domain, we intend to conduct routine briefings with key government stakeholders and implementation agencies, as well as with other donor organizations.
In Asia, two ACIAR-funded projects, the MAFF-funded CCARA, the GTZ-funded ICON (in preparation), BMZ-funded activities, and USAID-funded activities under the CSISA umbrella are the main funding mechanisms for this product line. NOW/WOTRO is funding the study on the effects of climate change on parasitic weeds. GTZ is funding two climate-change projects in Africa: RISOCAS in Senegal, Mali, and Madagascar, and MICCORDEA in Tanzania, Rwanda, and Uganda. A proposal for a third GTZ-funded project called CC&SPM in Benin, Ghana, Nigeria, Mozambique, and Tanzania has been submitted. A concept note for CC studies in the Niger River and Senegal River basins is currently being discussed with UEMOA. Additional funds are needed to finance experimental platforms in Egypt, Senegal, and possibly Mali and Nigeria. In LAC, CIAT-FLAR co-investments are supporting this PL.