Assessing Agro-Ecological Intensification Paradigms in Irrigated Rice Systems for Energy, Environmental and Economic Security in South Asia.

To feed everyone adequately, world food production must double within the next 30 years. Projections indicate that production of rice, wheat, and maize will have to increase by about 1.1%, 1.7%, and 2.9% per annum, respectively, over the next four decades to ensure food security in South Asia. Widespread inefficiency of resource use, depletion or degradation of soil and water resources, rising production costs, and increasing environmental pollution are major concerns associated with crop production in South Asia in addition to negative impact of climate change. South Asia is one of the two regions of the world that, without sufficient adaptation measures, will likely suffer negative impacts of climate change on several crops that are important to large (30% of the world) food-insecure human populations. Improving agriculture adaptation and reducing agriculture’s global warming contribution are the key factors that will shape the future severity of climate change impacts on food production.

Future production increases must come from stabilizing yields in areas where yields are already high and increases in production in areas where yields are currently low, while promoting ecological sustainability. The agricultural revolution over the next 40 years has to be the eco-efficiency revolution, with 50 to 100% increases in the efficiency with which scarce resources of land, water, nutrients, and energy are used. Importantly, this greater output and efficiency has to be achieved while maintaining or restoring land, water, biodiversity, and agro-ecosystems. Only a holistic approach can address issues associated with crop and resource management as they entail multiple and interacting factors and effects. Intensification of agriculture is necessary, but can be environmentally challenging.

We under the umbrella of a regional program Cereal System Initiative for South Asia assessed four ecological intensification paradigms at four sites representing  distinctly different agro-ecological conditions representing major food production systems of most populated regions of South Asia. Two broad groups of cereal-based rotations were considered: wheat-rice and rice-rice with integration of either a legume (and/or potato) or substituting a cereal with maize. Using a whole suite of primary and secondary performance indicators related to grain and energy productivity, input (labor, water, nitrogen, solar radiation and energy) usages, economics and greenhouse gas emissions/global warming potential, we demonstrate that a high level of eco-efficiency with large rice system productivity is economically feasible.