The Temporal And Spatial Chracteristic Of Agriculture Non-Point Source Pollution And Its Economic Factors In Zhejiang Province

Since the economic reform and opening-up, the rapid development of the economy have led to improve the agricultural output and rural living standards, but with industrial wastewater and urban sewage has been effectively controlled, we must realize that agricultural non-point source pollution has become an important driving factor for water pollution. Eutrophication and nitrate-rich in groundwater are not only harmful to aquatic plants and animals but also for human health and survival, so the agricultural non-point source pollution will gradually become the main objective of the current and future water pollution control in Zhejiang province.In this paper, agricultural non-point source pollution in Zhejiang Province is the research object and using inventory analysis to measure the emissions of agricultural fertilizers, livestock, farmland solid waste and domestic waste of chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP).This paper estimates the four types of pollution in Zhejiang Province and 11 cities of units COD, TN, TP of emissions,emission concentration and unit contribution rate, and analyze the trend of changes in agricultural non-point source pollution and spatial differentiation of urban agriculture non-point source pollution in Zhejiang Province. With the above calculation results, using environmental Kuznets curve (EKC) theoretical and empirical research paradigm to analyze the relationship between economic development and agricultural non-point source pollution, and elaborate stages and future trends of agricultural non-point source pollution in Zhejiang Province. Joining the economic factors in agricultural non-point source pollution basis model of environmental Kuznets curve, and analyze the reasons of emissions of agricultural non-point source pollution from economies of scale, structure effect and technology effect.On the above research, the main conclusions of this study are as follows:(1) Agricultural non-point source pollution of COD, TN, TP emissions and emission concentration show an overall growth trend in Zhejiang. From the angle of emission concentration, TN emission concentration is the most serious; following by TP emission concentration, COD emission concentration has not been exceeded. From the province’s unit contribution rate of COD emissions, the decreasing order is livestock>domestic waste> farmland solid waste; from the province’s unit contribution rate of TN emissions, the descending order is agricultural fertilizers>domestic waste>Livestock>farmland solid waste; from the province’s unit contribution rate of TP emissions, the decreasing order is livestock>farmland solid waste>agricultural fertilizers>domestic waste.(2) The average emissions and emission concentration of agricultural non-point source pollution in 11 cities of Zhejiang Province are quite different, the emissions of Hangzhou, Jiaxing, Ningbo, Jinhua and Wenzhou are in the forefront, Lishui, Zhoushan are the smallest; the emission concentration of Jiaxing, Huzhou, Shaoxing, Zhoushan, Ningbo are in the front row, the lowest emission concentration is Wenzhou, Lishui area. According unit contribution rate analysis, livestock and domestic waste pollution is the major agricultural non-point sources in Zhejiang.(3) From agricultural non-point source pollution Kuznets curve estimation results, the relationships between agricultural non-point source pollution and economic growth are not in line with inverted U-shaped curve, where the relationship between agricultural fertilizers, domestic waste and economic growth is an inverted U-shaped relationship, but the turning point of domestic waste’s inverted U-shaped curve is higher than agricultural fertilizer, indicating that rural life pollution emissions will appear a downward trend in a higher level of economic development, which also shows that domestic waste pollution is more serious than agricultural fertilizer pollution in the future. N-curve relationship between livestock pollution and economic growth reminds us to strengthen livestock pollution control and prevent pollution emissions increase again in the future. The relations between farmland solid waste pollution and economic growth is inverted N-curve, although there are some areas have crossed the second turning point, but the solid waste pollution emissions will continue to increase in most areas of farmland.(4) The empirical analysis show that the rural population scale, the proportion of livestock output in agricultural value, the sown area of economic crops have a positive effect on agricultural non-point source pollution emissions, while the role of agricultural technology abatement progress depends largely on the micro-level farmers environmentally friendly technologies preference, so the technological advances in agriculture have not an positive effect on environmental pollution. But the influences of crop structure on TN emissions are not significant, and symbolic coefficient is negative, which is contrary to expectations. One possible reason is the amount of agricultural fertilizer is decline every year, another reason is Zhejiang Province in 2006 promoted soil testing and fertilization techniques, now the structure of fertilizer gradually tend to rationalize, improving crop fertilizer nutrient absorption rate and reducing the loss of nitrogen, so the promotion of environmentally friendly technologies may play an inhibitory effect on agricultural non-point source pollution.