基于NSGA-Ⅱ的鄂尔多斯市多目标水量分配结构优化

Optimization of Multi-objective Water Quantity Allocation Structure in Ordos City Based on NSGA-Ⅱ

在水资源短缺背景下,优化区域有限水量分配结构、提高非常规水利用效率对促进西北地区经济社会发展和生态环境保护具有重要意义。结合用水公平系数和供水次序系数等表征参数,以缺水量最小、经济效益最大、水体污染物排放量最小为目标函数,采用第二代快速非支配多目标优化算法(NSGA-Ⅱ),构建了区域水量分配模型,并选取鄂尔多斯市为典型研究区,采用区间估计法预测了鄂尔多斯市供需水量,分析了多种水量分配方案下鄂尔多斯市未来的缺水程度及产业结构变化情况,对区域多目标水量分配结构进行了优化。结果表明:规划年2025年时,鄂尔多斯市的缺水率为31.5%,全市第一产业用水占比降低了12.8%,地下水使用量减少了6.3%,非常规水利用率提高至91.9%,产业用水结构和水源供水结构得到改善。研究结果可为鄂尔多斯市经济社会可持续发展与水资源高效利用提供参考。

In the context of water shortage,optimizing the distribution structure of regional limited water volume and improving the efficiency of unconventional water use are of great significance to promote the socioeconomic development and ecological environment protection in Northwest China.Combined with the characterization parameters such as water use equity coefficient and water supply order coefficient,taking the minimum water shortage,the maximum economic benefit and the minimum discharge of water pollutants as the objective function,the second generation fast non dominated multi-objective optimization algorithm(NSGA-Ⅱ)is used to construct the regional water allocation model.Taking Ordos City as a typical study area,the water supply and demand in Ordos city are predicted by interval estimation method.The water shortage degree and industrial structure changes of Ordos in the future under various water allocation schemes are analyzed,and the regional multi-objective water allocation structure is optimized.The results are as follows.In 2025,the planning level year,the water shortage rate in Ordos will be 31.5%,the proportion of water used in the primary industry in the city will be reduced by 12.8%,the use of groundwater will be reduced by 6.3%,and the utilization rate of unconventional water will increase to 91.9%,and the industrial water use structure and water source supply structure will be improved.