Small And Medium-sized Water Environmental Capacity Calculation In A River Basin

Water is not only an important part of the ecological environment, but also irreplaceable naturalresources of human life and social stability. But along with our country social economic development byleaps and bounds in recent decades, the water pollution problem increasingly prominent, and waterenvironment quality decreased obviously, serious impact on the development of our country. To solve theproblem of water pollution in our country, should first pollutant total amount control and the determinationof pollutant total amount was conducted on the basis of water environmental capacity. Therefore, he basinof water quality, water environmental capacity to conduct a comprehensive and systematic analysis andriver basin water environment capacity of pollutants were determined, on the basis of water pollutant totalamount control, is also the basis for effective protection and rational utilization of water resources.Research on basin water environment capacity calculation, can make reasonable pollutant total amountcontrol target, synchronization of river basin water resources and economy development laid a solidfoundation.River seasonal variation is larger in the north of China, summer and fall season river runoff is bigger,more rainfall, and less rainfall in the winter and spring were river runoff is relatively small, the waterenvironmental capacity calculation is often in the most the discontinuous river water environmentalcapacity as a benchmark, this article takes Kaifeng city river system as an example, using the integratedmodel and a one-dimensional steady-state model calculating the cuts in90%and75%under the assuranceof the mutagen city of water environmental capacity, through the comparison and analysis, find a moresuitable for accounting Huiji river method of river water environmental capacity, and the method to thewater environmental capacity of small and medium-sized rivers in the north of China accounting. Amongthem, the largest chemical oxygen demand (cod) emissions for agricultural pollution sources, the secondpollution sources for the life, minimum for industrial pollution sources, various kinds of pollution sources,the biggest ammonia nitrogen pollution sources for the life, followed by industrial pollution, agriculturalpollution sources is minimum..In this paper, using statistical data of2001～2010, combined with some measured data of hydrologyand water resources survey in KaiFeng,90%and75%in reliability, water flow conditions, the use of integrated model and a one-dimensional steady-state model cuts Huiji river watershed of the main pollutionfactors of water environmental capacity of COD and ammonia nitrogen in business accounting, by theresults of two models and the suitable conditions of comparative analysis, and use a new method combiningwith the characteristics of Huiji river reach to accounting Huiji river basin water environment capacity.Using comprehensive cut calculation of water environmental capacity model, the only consider waterfunction areas under section water quality standard rowRiver water environmental capacity calculation model is commonly used in two kinds, one kind isbased on the pollutant diffusion dilution and degradation in water self-purification mechanism model of onedimensional steady state capacity, the other is based on the theory of the law of conservation of matter"comprehensive cutting capacity model". One-dimensional steady-state capacity model for steady state andsubject to rivers completely mixed water pollutant reduction of conditions, lead to the calculation results ofpartial object is less than the river’s capacity value; The latter because of not considering pollutiondegradation mechanism of pollutants into the river after the period of the characteristics of the mixingprocess, causes the accounting results than the real object river water environmental capacity is big. Thisstudy combined with the actual situation of river, at the same time, considering the advantages anddisadvantages of the two models, the two models of cross application (that is, the capacity of compositemodel) calculating the water environmental capacity of small and medium-sized rivers, in close to the onedimensional steady capacity model application condition of the river Using one dimensional steady statecapacity model, other river is a comprehensive cutting capacity model calculation.In this paper, using statistical data of2001-2010, combined with some measured data of hydrologyand water resources survey in KaiFeng,90%and75%in reliability, water flow conditions, the use ofintegrated cutting capacity model, the capacity of one dimensional steady state model and compositecapacity model Huiji river watershed of the main pollution factors of water environmental capacity of CODand ammonia nitrogen in business accounting, by comparing the calculation results and applied conditionsof each model can be seen:"compound capacity calculation method of the result of the" closer to the objectof river real capacity. And this method is extended to medium and small basins in northern China in thewater environmental capacity calculation and provide quantitative basis for river pollution management.Pollutant total amount control of water environmental capacity research is to provide quantitative basisfor the accurate calculation results of the direct relationship between the regional water pollutants emission reduction task, relationship can develop scientific total amount allocation scheme, whether the relationshipbetween the units or various pollution sources to scientific and reasonable allocation of emissions allowed.Water environmental capacity calculation result according to the formula-regional pollutant emissionsstatus=water pollutant emissions cuts existing tasks "to be seen. Water environmental capacity calculationresult value is big, water pollutant emission reduction task is big, existing enterprise amount increases, willaccelerate water pollution; On the other hand, the water environmental capacity calculation result valuepartial hours, small water pollutant emissions cuts existing tasks, enterprise sewage is restricted, the riverwater environmental capacity idle, further influence the development of regional economy. In conclusion,accurate water environmental capacity calculation results is the basis of the regional water environmentcomprehensive improvement, only the accurate calculation of regional water environment capacity, by therelevant administrative department of environmental management to provide accurate quantitative basis, inorder to achieve the harmonious development of regional society, economy and environment.