Analysis And Research About Loading Ability Of The Water Environment Of Poyang Lake

The Poyang Lake, a major lake located in JiangXi Province, is the largest lakein middle-down part of the Changjiang River. The water environment of thePoyang Lake has quite huge influence on the area around the lake as well asthe entire middle-down part of the Changjiang River. Since the major source ofpollution to lakes is contamination which is the by-product of human-being'sactivities, protecting the water environment of lakes would certainly lead toconstrains on the daily life and the economic entities of the community aroundlakes.The present study investigated the loading ability of the water environment ofthe Poyang Lake. Specifically, the capability of the lake environment wascalculated. Based on the capability index, the indices for the lake's loadingability in domains of the sewage emission, the development of social economy,and the ecological safety were calculated. On one hand, the loading ability ofthe water environment of the Poyang Lake for different indices were calculatedbased on sub-indices. On the other hand, AHP was utilized to generate thenumerical system which indicates the extent to which each individual indexwould influence the loading ability of the entire lake. These two calculationmethods were combined to obtain the loading ability of the water environmentof the Poyang Lake.The outline of the present study is as follow:(1) The introduction part emphasized the meaning of investigating theloading ability of the water environment. After reviewing the currentliterature in this field, the definition and the connotation of the loadingability of lakes were stated. Furthermore, the necessity of conductingstudies in this field was discussed.(2) Based on investigating the natural geographical situation, the social economy, and the ecological environment of the lake area, the presentstudy analyzed the major influence factors responsible for pollution to thewater environment of the lake as well as the reciprocal relationshipbetween those factors and the lake environment, utilizing the datacollected about the major polluting material and the major emission sourceof pollution.(3) According to the distribution of the pollution sources and thecharacteristics of the water environment of the lake, the present studyproposed a plan to divide the entire lake into several different functionzones. The diffusion modes of the water quality for different zones wereascertained. The maximum amount of pollution (i.e., the loading ability ofthe water environment of the lake for pollution) was calculated whilemaking sure that the standards for the water quality were met.(4) The study analyzed the pollution emission ratio of various kinds ofsewage produced by the human-being activities in daily life and worksettings. Under the constrain of the loading ability of the waterenvironment, the multi-goal proposing model was employed to calculatethe maximum loading ability of the lake for the development of socialeconomical entities.(5) The study calculated the sub-indices for the loading ability, by utilizingthe sub-indices loading indicator model. Furthermore, the weight systemwas integrated into the process of calculating the total value of the lakecapability in current year and in the predicted year.The results indicate that if the pollution emission ratio stays on the same level,the water environment of the Poyang Lake can not afford the population andthe development of the social economical entities around the lake in thecurrent year (i.e., in 2005) and in the predicted year (i.e., in 2015), according tothe analysis of the loading ability of the Poyang Lake.Since the major pollution sources are living sewage and farmland waste water, the present study proposed strategies to control the water pollution such asdeveloping the marsh-gas facilities in villages and small towns, guidingfarmers to disseminate and fasten fertilizers in a scientific way, and enhancingthe ability to manage the city sewage. Furthermore, based on the planproposed in the study, the researcher calculated the loading ability in thepredicted year given the premise that the environment-protecting strategiesare implemented. Comparing this ability with the predicted loading ability if thepollution emission level remains the same, results supported the flexibility andthe efficiency of the proposed plan. The current study provided reasonablesuggestion in terms of protecting the water environment of the Poyang Lakeand optimizing the development of the economical entities around the lake.