基于GWAS模型的灌区水资源优化配置研究:以淠史杭灌区为例

针对淠史杭灌区“蓄、引、提、调”相结合的“长藤结瓜”式灌溉系统，为实现灌区间、上下游的优化联合配置，采用GWAS模型，通过划分水资源配置子单元和设置调蓄节点，采用公平性最优和供水缺水率最小作为目标函数，总量控制、供水能力、分质供水等作为约束条件，将水资源优化配置问题模拟为生物进化问题，采用基于精英策略的非支配遗传改进算法求解，建立了适用于淠史杭灌区的水资源优化配置模型。配置结果表明:灌区引水量最大，其次为当地地表水和边界提水站提水，中水和浅层地下水作为补充。通过序列年水资源配置，发现相同频率年在处于不同丰枯年份时，可供水量存在明显差异，因此在进行区域水资源配置时，仅分析50%、80%或90%几个频率年往往不能真实反映可供水情况，需进行长序列调配分析。基准年、2025年和2035年在50%和80%保证率下基本不缺水，灌区水资源可实现基本供需平衡。如遇连续干旱年，90%保证率下缺水较严重，可通过合理开发当地水、新增外调水来降低缺水程度。

GWAS model-based optimal allocation of water resources in irrigation district

Aiming at the irrigation system of canals combined with reservoirs of Pishihang Irrigation District，an optimal water resources allocation model for the irrigation district is established by means of simulating the optimal water resources allocation as a problem of biological evolution and solving it by the elite strategy-based improved non-dominated genetic algorithm with the GWAS ( General Water Allocation and Simulation Software) model through dividing the water resources sub-units and setting regulation and storage nodes as well as taking the optimal fairness and the minimum water supply shortage rate as the objective functions，the total amount control，water supply capacity and dual water supply，etc． as the constraint conditions，so as to realize the optimal combined-allocation among the irrigation areas and between the upstream and downstream areas． The allocation result shows that the amount of water diversion to the irrigation district is the largest，which is followed with the local surface water and the water from the boundary pimping stations and supplemented by the reclaimed water and shallow groundwater． Through the water resources allocation of sequential years，it is found out that obvious differences are there among the available water supply amounts of the years with same frequency in different wet and dry years，thus the actual situation of the available water supply amount cannot be reflected through only analyzing several years with the frequencies of 50%，80% or 90%，and then a long-term regulation and allocation analysis is necessary to be carried out． Under the guarantee rate of 50% and 80% in the base years，2025 and 2035，no water shortages are to occur and the basic balance of supply and demand of the water resources within the irrigation can be realized as well． In case of continuous drought years，water shortage is to be serious under the guarantee rate of 90%，however，the degree of water shortage can be reduced through reasonable development of the local water resources and the newly added water diversion from the outside．