Study On The Verification Theory And Method Of Water Resources Management Indices Based On Hydrologic And Material Cycle Simulation

China is a country with serious shortage of water resources,water use efficiency of industry and agriculture is low and water resources are wasted seriously.Extensive development and utilization of water resources have also brought serious water pollution problems.The bottleneck system of water resources,water ecology and water environment has seriously restricted the development of China's economy and society.The reasonable water resource management indicators formulation and ecological protection strengthening are urgent.The report of the 18th CPC national congress raised the building of ecological civilization to a new level,the new changes have taken place in the way and management of water use in China.In 2011,the central government clearly proposed to implement the strictest water resources management system,clearly required the establishment of red line indicators for water resource management,and the implementation of total amount control and efficiency control.In 2017,the report of the 19th CPC national congress put forward the concept of Chinese green development for new Era,to implement a strict system of ecological protection,strengthen ecological and environmental protection and restoration,form a green development model,and rebuild blue hills and green streams.The development concept of"lucid waters and lush mountains are invaluable assets" provides guidelines for China's future economic development and ecological protection.Combining the most stringent water resource management system in China with the research on the hydrological cycle and its associated processes,to improve the rationality and feasibility of water resource management indicators is a major scientifi c demand faced by China's water resource management practices,which is also the research direction that the water resources discipline needs to break through.However,the current research on the assessment of water resource management indicators in China is still in the stage of discussion.There is no clear theoretical basis for the nature of the verification of these indicators.The evaluation method based on water cycle mechanism and scientific evaluation system has not been formed yet.Based on natural and artificial composite water cycle theory,this article systematically puts forward the verification theory and method of water resources management indices based on hydrologic and material cycle simulation.The Water Amount,Quality and Efficiency Regulation model based on the SWAT(SWAT_WAQER)model has been developed and successfully applied to the nanliujiang catchment where water resources and water environment problems are prominent.In order to quantify the indices of water resource management in the nanliujiang catchment,multiple scenarios include economic and social development,water conservation,pollution control and ecological protection have been taken into account,and a multiple objectives decision-making screening model which comprehensively considers the five major systems of economy,society,resources,environment and ecology have been build for program optimization.The main parts of this paper are as follows:(1)In view of the requirements of the most stringent water resource management system and the concept of green development style in China,the work systematically puts forward the verification theory and method of water resources management indices based on hydrologic and material cycle simulation,on the basis of the combined natural and artificial water cycle theory,taking the coordinated development of the five dimensional attributes of the economy,society,resources,ecology and environment of water resources as the approval crnteria,taking "index selection-scenario setting-scheme simulation-effect evaluation-index verification" as the verification idea,taking water use control,water use efficiency control and pollution emission control as the approved target.And the work also proposes scheme setting,model framework and scheme evaluation method.(2)The Water Amount,Quality and Efficiency Regulation model(SWAT WAQER)is developed by improving the SWAT model.A new discretization method is adopted to solve the problem that the boundaries of natural subbasins,administrative regions and irrigated areas do not coincide with each other.The model possesses the function of economic and social development prediction simulation,water demand simulation,natural-artificial water cycle coupling simulation,water quantity and quality coupling simulation as well as water resources allocation simulation.Rice yield,runoff,evapotranspiration,sediment and water quality are tested by the model,which verifies that the SWAT WAQER model has reliable simulation performance and good simulation effect,and can be used as a powerful supporting tool for this reserch.(3)This work takes the Nanliujiang catchment as the study area,quantitative the water management indices in 2030 by the evaluation and optimization of programs:the total water consumption in the area is 2.328 billion m3,including 2.326 billion m3 of surface water use,398 million m3 of domestic water use,142 million m3 of industrial water use,1.745 billion m3 of agricultural water use,and 43 million 3 of ecological water use.The discharge amount of nitrogen into the river is 10965t,including 1821t from point source and 9144t from non-point source.The discharge amount of phosphorus into river is 1250t,including 148t from point source and 1102t from non-point source.The water consumption per 10000 yuan industrial increase value is 27m3,and the effective utilization coefficient of irrigated water is 0.60.(4)The responses of water and material cycle in the Nanliujiang catchment to climate change under the HadGEM2-ES model with the three emission scenarios of RCP2.6,RCP4.5 and RCP8.5 are analysed respectively.The precipitation and temperature in the catchment will increase in the future under the three emission scenarios;the runoff in the catchment presents a decreasing trend except the RCP4.5 scenario,runoff will increase by 4.0%under RCP4.5 emission scenario,and will decrease by 10.8%under the RCP8.5 scenario;under the three emission scenarios,the actual evapotranspiration will increase by 6.4%,4.5%and 6.3%,respectively;the pollution loads show different trends under the three emission scenarios.For RCP2.6 scenario,the nitrogen load and phosphorus load in the catchment will be reduced by 39.6%and 46.5%respectively.For RCP4.5 scenario,the nitrogen load and phosphorus load will decrease by 27.9%and 28.6%respectively.For RCP8.5 scenario,the nitrogen load and phosphorus load in the catchment will increase by 6.9%and 7.8%respectively.In the future,the rice yield per unit area in the catchment will decrease.Under the three emission scenarios,the average rice yield will decrease by 2.3%,0.67%and 3.4%,respectively.(5)The RCP4.5 emission scenario is selected,the SWAT_WAQER model is used to simulate and evaluate various schemes,and the water resource management indices of the Nanliujiang catchment in 2030 under the condition of climate change is approved:the total water consumption in the area is 1.818 billion m3,including 1.818 billion m3 of surface water use,398 million m3 of domestic water use,142 million m3 of industrial water use,1.235 billion m3 of agricultural water use,an d 43 million m3 of ecological water use.The discharge amount of nitrogen into the river is 8537t,including 1821t from point source and 6716t from non-point source.The discharge amount of phosphorus into river is 750t,including 148t from point source and 602t from non-point source.The water consumption per 10000 yuan industrial increase value is 27m3,and the effective utilization coefficient of irrigation water is 0.60.