基于MEP和DEA的水资源短缺风险损失模型及其应用

本文基于最大熵原理(MEP)和数据包络分析(DEA)建立了水资源短缺风险损失模型,可模拟水资源的随机性和经济效益。首先利用最大熵原理模拟缺水量的概率分布函数;其次建立数据包络分析模型计算用水效益系数;最后建立水资源短缺风险损失函数。以北京市为例,研究多种不同来水条件下的风险损失。结果表明:2020年北京市水资源短缺风险损失在2006年的来水条件下将达到最大,约为740亿元;在2008年的来水条件下将达到最小,约为683亿元。2020年北京市水资源短缺风险期望损失约为268亿元,远低于2020年在1956—2012年来水条件下的水资源短缺风险损失的平均值。利用南水北调水和再生水后,2020年北京市在不同来水条件下的水资源短缺风险损失值和期望损失值均有大幅度的降低。

A model for water shortage risk loss based on MEP and DEA and its application

A model for water shortage risk loss is developed based on the maximum entropy principle (MEP) and data envelopment analysis (DEA), which can simulate the economic benefit of water resources and random uncertainty in the water resources system. Firstly, the probability distribution of water shortage is simulated based on MEP;secondly, water use benefit coefficient is computed by DEA;finally, water shortage risk loss function is constructed. Taking Beijing for example,values of risk loss under many differ-ent inflow conditions are studied. The results show that the water shortage risk loss of 2020 in the inflow conditions of 2006 will reach the greatest (about 74 billion CNY) and in the inflow conditions of 2008 will be the least (about 68.3 billion CNY);the expected risk loss of 2020 is about 26.8 billion CNY,far below the mean risk loss of 2020 in the inflow conditions of 1956-2012. After using reclaimed water and South-to-North transferred water, the values of water shortage risk loss and expected loss of 2020 under different inflow conditions are reduced greatly.