Research On The Evaluation Of Water Resources System Efficiency And The Design Of Reward And Punishment Mechanism Based On DEA Model

Since the 21st century,water resources crisis and ecological environment deficit have become increasingly serious due to the increasing intensity of human activities.At present,countries worldwide are facing the common challenges of water resources crisis These crises will not only ruin the prospects of economic development,but also threaten social stability and human survival.Rapid economic growth and the acceleration of urbanization in China have resulted in the dual threats of water shortage and serious water pollution.Therefore,the decision-makers are no longer satisfied with measuring the efficiency of the independent Water Use(WU)system or Wastewater Treatment(WT)system.They eager to know the comprehensive performance of the integrated WUWT system and the specific reasons for its inefficiency.Furthermore,the large regional imbalances in the Water Resource Environmental Carrying Capacity(WRECC)pose challenges to sustainable economic and social development in China.In order to guide the regions to improve the WRECC effectively and to promote the sustainable development of the regions,it is critical to clarify the specific improvement direction for different regions.In this context,the relative efficiency of the integrated water resources system and its subsystems are measured firstly.Secondly,WRECC-based Reward and Penalty Mechanism(RPM)is designed on the basis of efficiency evaluation.This research has important guiding significance for the government to formulate water resources protection policies and improve the WRECC performance of the evaluated regions.The main contributions and innovations of this paper are as follows:(1)This paper considers both WU and WT as a mixed network structure two-stage WUWT system to provide more comprehensive efficiency evaluation.In the first stage(WU subsystem),there are two parallel units,economic and social WU sub-minors,which consume water and capital to produce economic and social benefits.Meanwhile,the undesirable wastewater inevitably arises,which is treated in the second stage(WT subsystem),and the untreated wastewater will be discharged as the final unexpected output.In order to assess the performance of this integrated WUWT system,an extended mixed network structure two-stage Slacks-Based Measure(SBM)Data Envelopment Analysis(DEA)model is established to measure the detailed efficiencies and spot the weak link of the system.For case study,the provincial cities' data during 2014-2016 of China's Huaihe River basin are selected to verify the practicability of the proposed approach.(2)According to the two major problems of water shortage and serious water pollution,this paper sets up a series of evaluation indicators and designs a RPM for the regions in a basin based on the WRECC performance using DEA benchmarking model.In this RPM,since the evaluated regions always orient their activities towards certain goals at the initial stage,first,this paper finds the closest goal for each indicator according to the previous performance using a DEA benchmarking model.Secondly,the specific rules of implementing the RPM are designed according to the policy requirements,that is,the different alert level of each indicator can be determined according to the achievement degree of each index to the reference point,which is used to judge whether reward and punishment should be imposed on the region as well as the specific amount.However,the goals cannot be directly regarded as the reference points of the RPM because they are not related to the current period and there is no evidence that these goals can be achieved in the current period.Moreover,the best practices of the current period cannot be directly regarded as the reference points because the point of RPM is to identify and judge the current situation based on objective conditions rather than an occasional good or poor performance.Thus,an extended DEA model is developed to adjust the benchmarking to the goals to determine DEA targets that are achievable and represent best practices as reference points.Taking the resulting DEA target as the reference point ensures that the reference point can be reached in the current period;on the other hand,it also takes into account the objective fact that all evaluated regions might have taken the goal as the direction for their activities.The rewards or penalties of the current period can be determined based on reward and penalty plans at the final stage.Finally,a case study concerning the WRECC-based PRM of the top 10 cities in China's Huaihe River basin from 2014 to 2016 demonstrates the applicability of the proposed approach.The results show the gap between the actual performance and the DEA targets can be defined;how much improvement regions should make can be identified;and regions that should be rewarded or punished as well as the specific amount of money required can be determined.