The Current Situation And Controlling-Measures About Non-Point Source Pollution Of Tianjin

As the economic center of northern China, in recent years, due to rapid economicand social development and acceleration of urbanization, Tianjin faced the problem ofnon-point source （for short NPS） pollution, which has increasing influence on thequality of surface water. This paper aims at the research of NPS pollution control baseon the natural and social background in Tianjin, and adopting suitable measure toconduct the comprehensive survey on the key non-point source water pollutantindicators in every districts and counties such as the emission load of chemicaloxygen demand （COD） and ammonia nitrogen （NH₃-N），to analysis the emission loadand impacts of above pollutants, as well as presenting the direction andcountermeasure of whole city’s non-point source pollution control.This paper had researched on the topic of NPS pollution in Tianjin by fouraspects of source: urban runoff, agriculture runoff, livestock breeding and rural life.We also estimated and computed whole city’s NPS emission load by using the variousmethods such as correctional unit load method, standard farmland method, excretioncoefficient method and pollution produced per capita coefficient method. The researchshows that COD and NH₃-N emission load amount to161758.5tons and25358.9tonsin the city’s NPS pollutants in2010. The NPS-COD pollutants emission load orderedin size respectively: agriculture runoff, urban runoff, livestock breeding and rural life,and NH₃-N emission load ordered in size respectively: agriculture runoff, urban runoff,rural life and livestock breeding.According to the reference data, selected rural area NPS pollutants emissioncoefficient is0.1, and urban NPS pollutants emission coefficient is0.68. The resultsshow that the volume of city’s NPS pollutants discharged into the river:38063.73tonsof COD and5059.54tons of NH₃-N. For the composition ratio: the volume of urbanNPS pollutants discharged into the river of NPS-COD and NH₃-N covering67%and58%respectively, and volume of rural NPS pollutants discharged into the river ofNPS-COD and NH₃-N covering33%and42%respectively of whole city’s NPSpollution, the top five river of most amount of NPS pollutant discharged by are Jiyunriver, Dagu sewage river, Duliujian river, urban area of Haihe river and Beiyun river.Base on the experiences of NPS control form both domestic and foreign, wesuggest to implement the NPS pollution control: from the aspect of urban NPS we should increasing series projects on the management of municipal waste removal andtransportation, municipal solid waste resources utilization, reconstruction of centralurban drainage system and urban landscaping, in order to decreasing the city’s NPSpollution gradually. From the rural aspect, we should continually implement theproject of soil testing and fertilization as well as agriculture water-saving irrigationproject, to promote the project of massive breeding and resource utilization oflivestock and poultry excrement, to carry out the project of rural area environmentalfacilities construction and agriculture waste utilization combined with the process ofurbanization, and gradually reduce the rural NPS pollution. Finally depend on the“12th five-years plan of industries and sectors of Tianjin, we will figure out thecountermeasure of NPS pollution issue from the aspects of management andengineering...