Study Of Control Measure Of Rural Non-Point Source Pollution In Hangzhou

As the rural non-point source(NPS) pollution is a significant important factor for water environment deterioration in China, the problems of NPS in watershed have been focused in the world.The control technology of NPS pollution and its research progress was introduced in this thesis, and based on the investigation of rural NPS pollution in Hangzhou area, the NPS pollution loading of Qiandao Lake Watershed by Mean Concentration Method was calculated. In addition, the ecosystem management technologies of NPS pollution control were also proposed.Hangzhou area is belong to both of Qiantang River watershed and Tai Lake watershed, the rural area was 1827.06 km~2 and the population was 4.2908 million. The per capita net income of rural households was 5242 Yuan, the Gross Agricultural Output Value was 18.90 billions and occupied 9% of GDP of Hangzhou in 2003 year. The application of chemical fertilizer was 342kg/ha and pesticide was 14.3kg/ha that far above the average in developed country; Fuchun River watershed and Qiandao Lake watershed were polluted seriously in Hangzhou watershed. The application of chemical fertilizer and pesticide, domestic animal's excrement, rural garbage, living sewage and aquiculture were considered as the principal sources of NPS pollution of Hangzhou watershed, at least 32933 tons loss of TN and 5578 tons loss of TP happened every year.The annual rainfall of Hangzhou is 1489mm, Chun'an and Tonglu are as the most. The results show that NPS is the main contaminative source of watershed pollution according to the calculation of annual pollution loading of Qiandao Lake Watershed by Mean Concentration Method. More than 70% of the NPS pollution happened between April and September, comparing with the data measured by Hangzhou environmental monitoring station, the data calculated by Mean Concentration Method shows the 7.04% reduction of TN output and the 17.57% increase of TP output. Hence, Mean Concentration Method can be regarded as a handy and effective method to calculate the NPS pollution in Hangzhou watershed.Ecological management is an important approach to control the rural NPS pollution. For instance, we can apply ecological agriculture, castoff cycling and the construction of artificial wetland, pond, vegetation buffer belt to reduce the occurrence of NPS pollution from headstream and run off area. Furthermore we can also recur to the corresponding law, policy, economy, and education to put the NPS pollution control into effect.