Regional Agricultural Water Resources Optimal Allocation Based On The Agricultural Water Price

Water resources are essential to maintaining the basic needs of human production and life.Agriculture is the industry with the highest water consumption.Long-established and extensive water use patterns and management concepts have resulted in a series of problems such as low agricultural water prices,a low agricultural water-saving effect,and prominent imbalances in agricultural water use throughout the country.It is necessary to optimize the allocation of agricultural water resources,and the agricultural water price is the “primary driver” of the optimal system for agricultural water resources allocation.Therefore,based on the improvement of the agricultural water pricing model,this paper uses the interval two-stage stochastic programming model to study the optimal allocation of agricultural water resources based on agricultural water price.The specific results are as follows:According to the cost data of agricultural water supply projects in the study area and the application of the full cost pricing method and the current water resources cost collection policy,the agricultural water price is determined to be approximately 0.03 yuan/m3,which is close to the current agricultural water price of 0.02-0.05 yuan/m3.Analysis of the agricultural,industrial and domestic water consumption,water price,and the output value of the three industries in the study area reveals that the current accounting of agricultural water resources cost is too low,leading to an agricultural water price that is far lower than industrial and domestic water prices,and the role of the price lever in promoting agricultural water saving has not been realized.At the same time,the agricultural output value is the lowest among the three major industries,which does not fully reflect the value of water resources.It is necessary to formulate a reasonable agricultural water price in order to facilitate the scientific utilization of regional water resources as well as to protect the water resources and control water pollution.The shadow price and full cost of agricultural water are determined from macro-and micro-scales by building the input-output computable general equilibrium(CGE)model of water resources and improved full cost(IFC)agricultural water price model,and affordable water prices for peasants are combined to determine the agricultural water prices as well as the corresponding government subsidy policies.When using surface water,the agricultural water prices for maize planting is [0.286,0.476] yuan/m3,and the government subsidies for agricultural water supply projects are approximately 0.517 yuan/m3;the agricultural water price for rice planting is [0.101,0.179] yuan/m3,and the subsidies should be less than 0.814 yuan/m3;and the agricultural water price for soybean planting is [0.180,0.307] yuan/m3,and the subsidies should be higher than 0.686yuan/m3.When using groundwater,the agricultural water price for maize planting is [0.317,0.507]yuan/m3,and the subsidies provided by the government for agricultural water supply projects are approximately 0.813 yuan/m3;the agricultural water price for rice planting is [0.131,0.210]yuan/m3,and the subsidies should be less than 1.110 yuan/m3;and the agricultural water price for soybean planting is [0.211,0.337] yuan/m3,and the subsidies should be above 0.983 yuan/m3.The multi-scale agricultural water price is introduced into the optimal allocation of agricultural water resources,and a two-stage stochastic programming(ITSP)model of regional agricultural water resources based on agricultural water price is established.With the goal of optimizing the total benefit of irrigation,the initial allocation based on agricultural water price and re-allocation based on water-saving incentive mechanism are carried out to verify the rationality of multi-scale determination of agricultural water price and the water-saving range of high water-consuming crops.After the initial allocation,it is found that raising the current agricultural water price to the calculated agricultural water price could be accepted by farmers.After reallocation,it is found that the optimal water-saving effect can be achieved when the irrigation water consumption per unit area is 85% of the original value.Under the condition of meeting the minimum water requirement of high water-consuming crops([171.90,257.85] × 108 m3),“raising the agricultural water price to the calculated level” and “reducing the irrigation water consumption of high water-consuming crops” are found to be the best linkage strategies for optimizing the allocation of agricultural water resources.In conclusion,the optimal allocation of agricultural water resources based on agricultural water price is researched on the basis of a multi-scale determination of the agricultural water price.A win-win method to aid agricultural water price reform and ensure that farmers receive the total benefit of irrigation is obtained,which provides policy recommendations for similar regions and countries to carry out agricultural water price reform and agricultural water resources management.