基于改进云模型的山丘区水资源多目标优化配置方案评价

Evaluation of multi-objective optimal allocation schemes for water resources in hilly regions based on improved cloud model

摘要

【目的】山丘区地形起伏和降雨时空分布不均,导致产汇流速度快,水资源难以有效收集,低地易洪涝、高地易干旱等问题,需结合山丘区的联合调配供水系统,缓解水资源供需矛盾。【方法】基于山丘区的联合供水方式,构建山丘区水资源多目标配置模型,并对NSGA-Ⅱ算法的交叉、变异和同一非支配层排序过程3个方面进行改进,用于模型求解。构建水资源综合评价体系,基于层次分析法对云模型进行改进,对方案集进行评价,比选得到综合最优的水资源多目标优化配置方案。最后将理论方法应用于南京市六合区,开展实例研究。【结果】(1)采用改进NSGA-Ⅱ算法求得六合区2025年和2035年的Pareto解集,分别以经济效益、社会效益、生态效益及协调最优为筛选条件进行筛选,得到2025年和2035年各7个配置方案集。(2)2025年与2035年的7个方案集经云模型等级评分后得到的最佳方案集均为方案四,即经济与社会协调最优方案,得分分别为89.87分、90.95分。【结论】构建山丘区水资源多目标优化配置模型,通过三个维度改进传统NSGA-Ⅱ算法,显著提升了解集的质量与合理性。建立多层次评价指标体系,创新性地采用改进云模型对方案进行量化评估,比选获得最优方案。该方法为山丘区水资源高效配置提供了“模型构建-算法优化-方案比选”的完整技术路径,可为决策者提供参考依据,缓解水资源供需矛盾,促进山丘区的综合协调发展。

Abstract

[Objective] The undulating terrain and uneven spatiotemporal distribution of rainfall in hilly regions result in rapid runoff generation and concentration, making it difficult to effectively collect water resources. This leads to issues such as frequent flooding in lowlands and droughts in uplands. Therefore, a coordinated water allocation and supply system for hilly regions is required to alleviate the conflict between water supply and demand. [Methods] Based on the integrated water supply approach in hilly regions, a multi-objective optimal allocation model for water resources in hilly regions was established. The Non-dominated Sorting Genetic Algorithm-Ⅱ(NSGA-Ⅱ) was improved in three aspects: crossover, mutation, and sorting processes within the same non-dominated layer, for solving the model. A comprehensive evaluation indicator system for water resources was developed. The cloud model was improved using the Analytic Hierarchy Process(AHP) for evaluating the set of schemes and selecting the overall best multi-objective optimal allocation scheme for water resources. Finally, the theoretical method was applied to the Liuhe District, Nanjing City, to conduct a case study. [Results] (1) The improved NSGA-Ⅱ algorithm was employed to obtain the Pareto solution sets for Liuhe District in 2025 and 2035. These sets were screened based on economic,social, ecological benefits, along with optimal coordination, resultsing in seven allocation scheme sets for each year.(2) After the seven scheme sets for 2025 and 2035 were evaluated using the cloud model rating, the optimal scheme set for both 2025 and 2035 was scheme 4, representing the optimal coordination between economic and social benefits. The scores were 89. 87 and 90. 95, respectively. [Conclusion] A multi-objective optimal allocation model for water resources in hilly regions is established.By improving the traditional NSGA-Ⅱ algorithm in three aspects, the quality and rationality of the solution sets are significantly enhanced. A multi-level evaluation indicator system is established. An improved cloud model is innovatively applied to quantitatively evaluate the schemes, and the optimal scheme is selected through comparison. This approach provides a complete technical pathway of “model construction-algorithm optimization-scheme comparison and selection” for efficient water resource allocation in hilly regions. It can provide a reference for decision-makers, alleviate water supply-demand conflict, and promote comprehensive and coordinated development in hilly regions.

关键词

山丘区 / 水资源优化配置 / 改进NSGA-Ⅱ算法 / 方案评价 / 改进云模型 / 多目标优化 / 帕累托最优解 / 层次分析法

Key words

hilly regions / optimal allocation of water resources / improved NSGA-Ⅱ algorithm / scheme evaluation / improved cloud model / multi-objective optimization / Pareto optimal solution / Analytic Hierarchy Process(AHP)

基金资助

国家自然科学基金项目(520031111)