Optimal irrigation for sustainable development considering water rights transaction: A Stackelberg-Nash-Cournot equilibrium model

Abstract

This paper focuses on water allocation in an irrigation district considering water rights transaction. The relationship between the reservoir authority and the sub-area managers is explored based on a novel Stackelberg-Nash-Cournot equilibrium model. In this framework, the reservoir authority has higher priority in allocating initial water rights to Sancha town, Danjing and Xinmin villages; after get the decisions from the reservoir authority, the sub-area managers decide water distribution to multi-crops planting areas and water rights transaction with the promise of Nash-Cournot equilibrium, then the reservoir authority can modify his decision by Stackelberg strategic interaction. To obtain the optimal irrigation strategy, fuzzy goal programming and genetic algorithm methods are applied. In this context, a Stackelberg-Nash-Cournot equilibrium solution can be obtained. The proposed model is applied to Sancha irrigation area, and the results show that more available water can be distributed in Sancha town while guaranteeing the equity among the sub-areas in this irrigation district; more water was utilized for wheat and oilseed rape than paddy and bean, which matched the fact that wheat and oilseed rape grow in quarters with relatively less rainfall inflows. A changeable and uncertain environment, regarding inflow levels, planting areas, and irrigation coefficient, take potential challenges to agricultural irrigation process. Hence, to cope with the challenges, cope with the future uncertainty and offer more information on the adjustment of agricultural irrigation patterns, scenario technique is applied by changing the three parameters – inflow levels, planting areas, and irrigation coefficient respectively. Finally, to highlight the superiority of the proposed model, a comparative analysis is conducted in a situation without considering the water market, which verifies the importance and effectiveness of water rights transaction.