Integrated Control Of Study On The Soil Erosion And Eutrophication In The Songhua Lake Basin

Lakes as one of the most important freshwater resources on the earth, have thefunctions of water supply, irrigation, regulation and storage, transportation, powergeneration, tourism, fishing, maintaining biodiversity and ecological balance andmany other features at the same time, which were the important basis for sustainabledevelopment and survival in the watershed areas. With the growing demand foragricultural products, large number of cultivated land, excessive application of thechemical fertilizers and pesticides in order to increase agricultural production,resulting in surface river water quality deterioration, eutrophication has broughtgreat pressure to the environment which was caused by total N and total P exceeded.Thus protecting the existing water supply sources to ensure the safety of residentsliving water has become an important subject of the current study, which hasfar-reaching practical significance by systematic study on non-point source pollutionin Jilin Province.Songhua Lake watershed is located in central and southern Jilin Province,across13cities and counties, accounting for22.7%of the total area of the province,its natural runoff accounted for81.7%of the total surface water resources for thesecond Songhua River Basin, accounting for38.7%of the total surface waterresources in Jilin Province. The eco-environment of Songhua Lake watershed wasgreat relevance to the integrated function of the whole whtershed. Over the years,lacking in combining consideration for ecological protection and environmentalmanagement and development of watershed resources, which caused the destructionof ecological balance and soil erosion, the more sediment and pollutants were putinto the lake, the heavier water pollution. Therefore, various theories and methodswhich combining multi-source remote sensing data and years of water qualitymonitoring data were used in this paper to lauch the system research on soil erosionand eutrophication of the Songhua Lake watershed. Through the extraction of useful information from the extensive collection ofrelevant literature data, then combined with the actual situation of the study area,what follows were the mainly research in this paper.First of all, in connection with the socio-economic and environmental status ofthe Songhua Lake watershed, and separate analysis of point sources and surfacesources of pollution, through the assessment for the contribution rate of the pointsource and point source pollution, then screening of the major sources of pollutionand pollution of the Songhua Lake watershed limiting factor to determine theexisting pollution state of survey region. Studies have shown that the contribution tothe point source pollution of the Songhua Lake watershed was21.31%, surfacesource pollution contribution was78.69%, the contribution rate of point source andsurface source pollution was the maximum since the pollution were concentrated inSonghuahu segment. Songhua Lake was serious affected by Huifa River and Jiaohe,Huifa River and Jiaohe is the two important sources of pollution in the SonghuaLake, compared with Jiaohe, the pollution contribution rate of Huifa river wasbigger, numbers of industrial pollution sources, the total quantity of wastewater andfour types of pollutant emissions came first, and thus cause pollution of SonghuaLake watershed. The reason for the lowest rate of point source contribution inRedstone segment was the pollution of rural life lightest where the rural populationwas smallest. Chemical fertilizers and loss of volume was concentrated in theSonghua Lake interval, in which the nitrogen fertilizer was applied frequently.Secondly, based on the memory of the Songhua Lake watershed in varyingdegrees of soil erosion, accelerated summer rainfall pesticides, fertilizers, manureand other pollutants into rivers affecting water quality.3S technology for monitoringsoil erosion and use of the Chinese Water Erosion Prediction model RKLSGCPSonghua Lake watershed soil erosion calculation, calculation of the loss of soilnutrients according to soil erosion modulus, and comparative analysis of the Districtof N, P loss reasons to determine the The influencing factors of soil nutrient loss.The results show that the Songhua Lake watershed soil erosion showing a gradualincrease from southeast to northwest trend, the lightest of the Songhua River, the source, the intensity of erosion is concentrated in the central region of HuifaEstuaries. The majority of the whole basin slightly eroded, the intensity of theerosion area of small and focused, the Songhua River Basin soil erosion in the range-192~5561.14t/(hm2h a) the. In the region of erosion, soil erosion to slightlyeroded and slight erosion-based, the area accounted for65.72%and33.83%of theSonghua Lake watershed; the amount of soil erosion is slightly eroded, and slighterosion were accounted for erosion of the total15.90%and81.87%moderateerosion accounted for2.15%, while the intensity of erosion accounted for only0.07%. From the watershed of each river system partition angle comparison analysis,the Songhua River, the source and Huifa River District of the N and P loss are veryhigh, this result makes the range of White Lake and the mouth of the Huifa theupper reaches of the Songhua Lake N-P content increased, exacerbate eutrophicationrisk.Again, select a reasonable the eutrophication inversion model to collect theSonghua Lake watershed2001to2010, ETM/TM image data using the ENVI, theArcGIS software inversion nearly10years of eutrophication in Songhua Lakewatershed factors (chlorophyll, total nitrogen, of COD, total phosphorus,transparency), from the perspective of the Songhua Lake interval analysis, due toHuifa River into more pollutants, causing the upper reaches of the Songhua Lakewater quality is inferior to the downstream, the more the better downstream waterquality, water quality in the best of the fullness of the reservoir.Finally, the main control from the total amount of pollutants, strengthen urbanand rural sewage and garbage disposal, prevention and control of agriculturalnonpoint source pollution, improve monitoring and enforcement system of fourpoint source pollution of the Songhua Lake watershed improvement measures.In this paper, multi-source spatial information, the use of RS and GIStechniques, digital environment model of tectonic units of raster data, thecombination of soil erosion assessment based on space technology andeutrophication assessment based on monitoring data, the study lakes and water ecology of the surrounding watershed, the study methods and study area certainlyinnovative. In this study reflect the Songhua Lake watershed soil erosion status, lakeeutrophication status is important to provide a scientific basis for the scientificmanagement of the Songhua Lake watershed eutrophication.