Study On Pollutant Fluxes Of Zhaojia River Based On Statistical Model-LOADEST

The paper is based on one of the parts of The12th Five-Year Major TechnologyNational Science " Research and Demonstration of Technology to Build the SubProblem of Liangjiang New Area of Chongqing City Water System "(2012ZX07307-001),which is “Determining the pollution load reduction and waterquality control plan”. Though studiing the theoretical of pollutant fluxes,the paper,taking Zhaojia River, one of the most important upstream rivers of Longjing Lake inChongqing Expo Garden, as the target, studies estimation of pollutant fluxs of ZhaojiaRiver based on statistical model—LOADEST.Based on LOADEST, the paperconstructs the regression equation of pollutant fluxes, determines the parameter of theregression equation,then checks the regression equation and estimates the averagemonthly throughput of COD,Ammonia Nitrogen, TN, TP,March2013-December.Thenpropose a quality evaluation method based on contaminant. The paper can provide basicdata for runoff pollution control program and supports for The12th Five-Year MajorTechnology National Science ".Firstly, through analysising the relationship between pollutant flux, environmentalcapacity, and the total amount control, the paper concluds the necessity of researchingon pollutant flux.At the same time,the paper has drawn the important significance ofestimating river pollutant fluxes accurately to some extent through reading a largenumber of documents, comparing and analyzing the current flux estimation methods athome and abroad, summarizing the characteristic, appliable scope and limiting factorsof each estimation method to point out the problems of the method. Then,the paper liststhe basic principles of choosing water quality model.Secondly, the study collected and sorted the data of natural conditions in ZhaojiaRiver and social development of the surroundings, including geographical location,topography, climate, hydrology, administrative divisions in Zhaojia River basin andfuture plans for surrounding areas, analyzing and summarizing pollution condition inZhaojia River basin to make a conclusion the pollution there was mainly characterizedwith eutrophication.Combining with the actual situation of Zhaojia River, the paperapplies an appropriate method which is based on LOADEST statistical model to providea basis for relatively accurate estimation of pollutant fluxs of Zhaojia River.Thirdly,according to basic data types of LOADEST,the paper the acquisition method of basic data.According to the characteristics of eutrophication in Zhaojia Riverbasin, identified factors were detected of COD, TN, ammonia and TP. Water samples fordetermining each pollution factor were collected in accordance with regulatoryrequirements and then each pollution factor concentration was measured in standardizedtest methods. Meanwhile, the study applied basin water allocation model principlecombined with the actual situation of Zhaojia River to make an estimation of ZhaojiaRiver flow into the lake.Next, regression equation for estimating each pollutant flux of pollution factorswas established by inputting the water quality data and traffic data into LOADESTstatistical model, which was optimized through Akaike information criterion and SPPCinformation criterion to preferably attain the most effective contaminant fluxesregression equation to calculate pollutant fluxes of COD, TN, ammonia and TP in eachmonth from March2013to December.Finally, The paper constructes water quality assessment method which is based onthe contaminant flux. Though AHP, the paper determines the influence weight of COD,TN, TP to the water quality of Zhaojia Then taking March2013for example, determinesthe water quality of Zhaojia River March,2014.