灌区多水源联合利用的模拟-优化耦合模型研究

【目的】构建灌区多水源联合利用的模拟-优化耦合模型,实现灌区多水源的合理配置。【方法】以不同水源的引水比例为决策变量,以用水成本最小、用水效率最高以及在约束范围内地下水位抬升幅度最大为目标,基于半分布式水量平衡模型与Pareto遗传算法构建灌区多水源联合利用的模拟-优化耦合模型,并对东北三江平原水稻灌区典型区域进行典型年与长时间序列的多水源优化配置。【结果】本研究构建的模拟-优化耦合模型得出的典型年内配水方案可以很好地处理目标函数间的复杂关系,得出倾向于不同目标的多水源配置方案;长时间序列多水源优化配置可实现灌区年际间的水资源调控,在控制用水成本与提高用水效率的同时,对地下水位进行长期调控,实现地下水采补动态平衡;通过调整目标函数,模型可以根据地下水位恢复时间的快慢制定出多水源配置方案;与现有配水方案相比,常规灌溉与控制灌溉条件下优化方案的用水效率基本保持不变,但用水成本分别降低4.3%与23.8%,净地下水补给量分别增加0.52×105 m3/hm2和1.73×105 m3/hm2。【结论】在综合考虑用水效率、用水成本的前提下,本研究建立的灌区多水源联合利用的模拟-优化耦合模型可得出有利于灌区地下水可持续发展的多水源配水方案,为灌区多水源配水技术提供理论支持。

A multi-objective fuzzy optimization model for cropping structure and water resources and its method

Cropping structure has a close relationship with the optimal allocation of agricultural water resources. Based on the analysis of the relationship between agricultural water resources and sustainable development, this paper presents a multi objective fuzzy optimization model for cropping structure and water allocation, which overcomes the shortcoming of current models that only considered the economic objective,and ignored the social and environmental objectives. During the process, a new method named fuzzy deciding weight is developed to decide the objective weight. A case study shows that the model is reliable, the method is simple and objective, and the results are reasonable. This model is useful for agricultural management and sustainable development.