Research On Optimizd Model Of Agricultural WEF System Under Uncertainty

The Fenhe Irrigation District is the largest artesian irrigation district in Shanxi Province.Agriculture,as a major water user,has a low utilization rate of water resources and disordered water intake.At the same time,there are errors in the measurement equipment and many assumptions in the optimization model,which cause a variety of uncertain factors,which together affect the comprehensive utilization of agricultural water resources.So,under uncertain conditions,how to ensure food production and power supply,rationally distribute and fully utilize existing water resources,and maximize agricultural income are very important to realize the sustainable development of regional social economy and effectively improve people’s lives.Therefore,aiming at maximizing agricultural net income,this paper constructs an optimization model of agricultural water resources-energy-food(WEF)system.On this basis,considering the serious uncertainty of water supply side,a single-objective agricultural WEF planning model is established,based on Information Gap Decision Theory(IGDT);in addition,considering the uncertainty in the grain production process,including the uncertainty of irrigation quota,grain yield per unit area and market price,a multi-objective interval stochastic programming model with maximum economic benefit and minimum carbon emission was established.The main research contents and conclusions are as follows:(1)Construct the optimization model of agricultural water WEF system.Incorporate planting and animal husbandry into the system,quantify the interaction and feedback within the agricultural water,food,and energy subsystems,with the goal of maximizing economic benefits,total energy,policy conditions,and model structure as constraints.It is allocated with the livestock rearing structure to obtain the irrigated area allocation,breeding structure allocation and water consumption allocation of different crops and livestock in different irrigation areas.After optimization,the net agricultural income of the Fenhe Irrigation District is 172 million yuan,the net irrigation water consumption is 3.1469 million m~3,the total water consumption quota for livestock is 7.1154 million m~3,the agricultural economic output value of water resources per unit area of the irrigation area is 15.79 yuan/m~3,and the output per unit area of land production is 15.79 yuan/m~3.The economic value is 169,500yuan/ha.After optimization,whether it is planting or animal husbandry,the agricultural economic output value has increased to a certain extent,indicating that the model has certain reference value for adjusting the agricultural structure and water allocation in Fenhe Irrigation Area to increase economic benefits.(2)Construct IGDT single-objective agricultural WEF planning model.Based on the optimization model of agricultural WEF system,aiming at maximizing agricultural income,introducing IGDT theory and considering the serious uncertainty of water supply,a decision-making model for crop planting area and livestock breeding structure was established,and applied to Fenhe Irrigation District in Shanxi Province.The results showed that the deviation factor increased from 0 to 0.5,and the interval was 0.1.The irrigated area of wheat,corn,and soybean decreased by 28%,23%and 45%,,respectively,and the number of pigs,mutton sheep,poultry,and beef cattle breeding decreased by52%,57%,11%and 51%,respectively.The model provides the fluctuation range of water supply that can be resisted by the allocation strategy of crop planting structure and livestock breeding structure under different expected income targets of decision makers.Risk-averse decision makers can evaluate different allocation strategies and take corresponding strategies to guaranteeing the expected income target provides new ideas for water resource allocation,agricultural structure allocation decision-making and risk assessment.(3)Build a multi-objective agricultural WEF interval stochastic programming model.Based on interval number programming and minimum deviation method,an optimization model is established with the goal of maximizing agricultural income and minimizing carbon emissions.The results show that when decision makers tend to obtain greater agricultural environmental benefits,the optimization scheme at?(28)0.6 is more advantageous.At this time,the net agricultural income of the irrigation area is[4.78,9.82]million yuan,and the agricultural carbon emissions are[14.72,18.05]million kg,the total amount of agricultural water[1.52,2.04]million m3.The model can provide decision support for water resource optimization,environmental sustainable development and food security in Fenhe Irrigation District.