节水压采区农业种植结构多目标优化研究——以衡水市为例

针对节水压采区水资源紧缺、种植结构不合理、灌溉定额较大等问题,提出了基于作物水分生产函数的多目标种植结构优化模型。以衡水市为例,以种植结构和灌水量为优化变量,以经济效益最大和总灌溉水量最小为优化目标,建立了多目标优化模型,通过改进的NSGA-II算法进行优化计算,得出了不同灌溉水价水平下对应的种植结构和灌水量调整方案。结果表明,小麦种植面积比现状种植面积有所减少,玉米、花生等耗水量小的作物面积有所增加。通过优化,合理提高灌溉水价可促进高耗水作物种植面积的减少,扩大低耗水作物种植面积。

Using Multi-objective Optimization to Restructure Agriculture with Consideration of the Constrains on Groundwater Extraction: Taking Hengshui as an Example

In this paper, we proposed a multi-objective optimization method to help restructure agriculture in at-tempts to resolve some problems facing agriculture production in north China, which include water resource shortage and overuse of groundwater forirrigation. The method is based on water production function for crops, with consideration of the constraints on groundwater extraction. Optimizing agriculture structureandwater use for irrigation could reduce agricultural water consumption and increase economic benefit. We took Hengshui as an example, calculating the optimized agriculture and water allocation for irrigation by maximizing economic bene-fit and minimizing agricultural water consumption;the optimization was solved by the improved NSGA-Ⅱ algo-rithm. The results showed that the planting areas of maize and peanut should be increased at the expense of win-ter wheat. We also found that rationally increasing the price of water for irrigation could reduce the areas of high water-demanding crops and increase the cultivation of low water-demanding crops. The results of our work pro-vide a guidance to adjusting agricultural water price and re-constructing the agriculture in this region.