Analysis And Optimization Study On Water Environment Carrying Capacity Of Liaoning Province Based On Water Environmental Capacity

Water environment,society and economy make up a complex system,water environment is an important part of the ecological environment.With the development of economy and society and the increase of human activities,the situation of water pollutant emission is becoming more and more serious in the future.People's demands for water environment quality are getting higher and higher.In order to solve these problems,it is urgent and necessary to determine water environment carrying capacity from the perspective of regional developing plan and water environment management.Water environmental carrying capacity is the best tool to measure the region's sustainable development.This paper puts forward the water environment carrying capacity's optimization model which is suitable for the economic and social development in Liaoning Province,it has more contemporary significance under the background of ecological civilization construction.This paper guide to complete the water environmental capacity's calculation and distribution based on the literature at home and abroad.This paper scientifically and rationally allocates water environmental capacity to district and county.The sources and quantity of pollutants in various regions of Liaoning Province were analyzed.Based on the allocation of water environmental capacity,the PSR framework model is used to establish the water environment carrying capacity index system in Liaoning province.At the same time,the method of the rough set attribute is used to reduce the complex index system.The weight of each evaluation index is determined by the entropy method.Finally,we can calculate the counties and districts' water environment carrying capacity in Liaoning province.So it can be simple and clear to reflect the water environment carrying situation in the Liaoning province.We focus on areas where water environment carrying capacity is weak in Liaoning province.The multi-objective optimization method is used to calculate and predict the maximum population,maximum economy,minimum COD pollutant emissions which supported by the water environment in 2020,2025 and 2030.The main research results of this paper are as follows:(1)Using the water quality model to calculate the Liaohe River,Hunhe River,Taizihe River mainstream and first class tributary.In 2015,the water environmental capacity of the Liaohe River was 65603.91 t/a,the water environmental capacity of the Hunhe River was 62004.76 t/a,the water environmental capacity of the Taizihe River was 55717.88 t/a.In the three rivers,the sequence of COD water environmental capacity from large to small is:Liaohe River>Hunhe River>Taizihe River.(2)Select the economic,social,environmental and other factors which include population,GDP,the state's emissions to construct the water environmental capacity allocation model.Ultimately,we achieve the allocation of water environmental capacity from rivers to districts.The distribution results show that the water environmental capacity is too high in the central area of the administrative map,while water environmental capacity is too small in the surrounding area of the map.The Liaozhong County,Tiexi District and Liaoyang County are the area with water environmental capacity greater than 10000 t/a.Their values are 18336.25 t/a,12743.19 t/a,10585.53 t/a.Dashiqiao City is the area where water environmental capacity is the least,only 78.30 t/a.(3)The number of pollutants in various regions of Liaoning Province was approved in 2015.In 2015,75%of the 41 major administrative regions exceeded COD emissions by more than 10,000 tons in the river of Liaoning Province.Among them,Panshan County's emissions are 85908.52 t,the largest amount of COD emissions.Overall,when harnessing point source pollution,we should increase the control of the non-point source pollutants.(4)Based on the water environmental capacity's PSR evaluation model,to calculate and analyze the water environment carrying capacity in Liaoning Province.The areas where water environment carrying capacity is very low are Changtu County and Zhangwu County.Their values were 0.1990,0.1283.The water environment in these two areas has collapsed.The water environment carrying capacity in the area of Kaiyuan City,Diaobingshan City,Tieling County,Mingshan District and so on are between 0.2?0.4.The water environment carrying capacity of these areas is weak.Water resources,economic development and ecological protection have been in a serious non-coordinated and fragile state.(5)Select the areas where the water environment carrying capacity is weak,such as Changtu County,Zhangwu County and Dadong District.According to the development requirements of the 13th Five-Year Plan,we can get:Changtu County,the optimized GDP and urbanization rate was 19.19 billion yuan,26.86%in 2015.It is estimated that GDP and urbanization rate will reach 52.80 billion yuan,55%in 2030.From 2015 to 2030,Zhangwu County and Dadong District's GDP and population also show an upward trend,but the growth rate is slowing down.