96 / 2024-01-17 17:03:52

A distributional optimization model for agricultural water management based on water-energy-food nexus and water cycle under climate change

Water-food-energy nexus analysis, further climate, uncertain programming, optimal irrigation water strategy, agricultural sustainable development.

Sustainable development is hindered by the conflicts in resources in numerous regions of the world. These challenges need to be addressed by an integrated and equitable way, especially for agriculture. In this study, an integrated agricultural water management optimization method is proposed to balance the economic, social and ecological conflicts from agricultural activities. The water-energy-food nexus analysis is adopted to recognize different agricultural activities and describe their input-output relationships. The spatial-temporal dynamics of water cycle driven by irrigation is depicted and combined within the nexus. Then, the impact of agricultural activities on economy, society and ecology is evaluated integrating footprint method and life cycle assessment. The key indicators and necessary restriction are selected as objectives and constraints of the optimization model. Meanwhile, the future climate data of typical scenarios are collected and processed as the inputs of the optimization model. The involved uncertainty from inputs and decision makers is analyzed and quantified. Aimed the constructed complex uncertain model, a multi-objective robust two-stage stochastic programming is developed to deal with the conflict objectives and different kinds of uncertainties. The established optimization framework is applied in Zhanghe Irrigation District and the results show that the method is capable to make tradeoff among conflicts during agricultural development and help achieve sustainability. However, compared with SSP1-2.6 and SSP2-4.5, SSP5-8.5 needs to consume large quantity of water and energy to guarantee crop water demand under current irrigation method, and water-saving equipment should be highly promoted in this scenario to improve water efficiency.