基于模糊集对分析的灌区水库旱限水位及供水策略优化研究

随着经济社会发展和气候条件改变，我国区域干旱问题日益突出，水库在抗旱减灾过程中的作用越来越凸显，旱限水位的提出与应用对有效发挥大中型水库在抗旱中的调控作用、缓解流域旱情具有重要意义。针对旱限水位研究现状，本文以史河灌区梅山水库为例，首先考虑城乡供水、农业灌溉、水力发电和生态环境等诸多因素，构建基于模糊集对分析法的水库灌区水资源系统运行效果综合评价模型，并以水资源系统综合运行等级最优为目标，以分期分级旱限水位、灌溉限供措施（基于水库来水特征和作物生长特性）为优化变量，运用免疫遗传算法进行系统优化求解，最后对比有无旱限水位下水库水资源系统综合运行效果，并分析了不同控制方式下水库供水变化和灌区作物因旱减产风险。结果显示：该优化方法相较于以水库供水经济效益为目标旱限水位确定方法，多项年均指标都有较大改善，其中梅山水库经济效益提高了46万元，充反调节水库水量增加了555万m³，而水库弃水量减少了566万m³；史河灌区塘坝供水量增加了253万m³，而作物减产率下降了3.32%，同时作物因旱减产风险降低了3.15%。可见，运用系统综合评估决策方法有利于改善水库灌区系统综合运行效果，提高系统水资源利用效率和水库灌区经济效益；优化的旱限水位控制和与作物生长特性相适应的优化供水策略相对于经验性控制能有效减少灌区中稻因旱减产率，为保障旱限水位的顺利实施和干旱时期农业灌溉抗旱提供有力支撑。

Optimization study of drought-limited water level and water supply strategy of the reservoir in the irrigation district based on fuzzy set pair analysis method

With socioeconomic development and climatic change, regional drought problems are increasingly serious and the role of reservoirs in drought resistance becomes more and more prominent. The proposal and application of drought-limited water level is of great significance for bringing into play the regulation role of large and medium-sized reservoirs in drought resistance and alleviating the drought situation in the basin. Aiming at the present study state of drought-limited water level, Meishan Reservoir in the Shihe Irrigation District was taken as an example in this paper. Firstly, the initial staged drought-limited water level was calculated based on urban water supply, agricultural irrigation, hydroelectric power generation, ecological environment and other factors. Then the fuzzy set pair analysis method was used to construct the comprehensive evaluation model of water resource system operation effect of reservoir and irrigation district. After that, with purpose of the optimization of comprehensive operation of water resources system, the immune genetic algorithm was used to optimize the optimization variables of the drought-limited water level and irrigation water supply limit measures (based on the characteristics of reservoir water inflow and crop growth characteristics). Finally, the comprehensive operation effect of reservoir water resources system with or without drought limit water level was compared, and the change of reservoir water supply and the risk of crop loss in irrigated district under different control methods were analyzed. This study show that compared with the drought limit water level with economic benefit as the single goal, the optimized drought limit water level in this study has greatly improved in many indicators, including the amount of reservoir filling and pond filling increased by 5.55 million cubic metres, the amount of abandoned water decreased by 5.66 million cubic metres, the water supply of pond dam increased by 2.53 million cubic metres, the economic benefit increased by 460,000 yuan, the crop yield reduction decreased by 3.32% and the risk of crop loss due to drought was reduced by 3.15%. It can be seen that the application of systematic comprehensive evaluation decision is beneficial to improve the comprehensive operation effect of the reservoir irrigation district system, and the utilization efficiency of water resources and the economic benefit of the reservoir are also improved. Compared with empirical control, the optimal water supply strategy adapted to reservoir inflow and crop growth characteristics under drought limit water level can effectively reduce the yield reduction rate of middle rice in irrigated areas and provide strong support for the smooth implementation of drought limit water level and agricultural irrigation in drought period.