Investigation Of Agricultural Non-Point Source Pollution In Jiangsu Based On Pressure-State-Response

The primary source, influence factors, and spatial distribution characteristics of agricultural non-point source pollution (ANPSP) in Jiangsu Province were analyzed by inventory analysis, equivalent standard load, cluster analysis and Control area methods based on the" pressure-state-response" mechanism.Results showed that the emissions of COD, TN and TP from NPSP were155.23,62.34and9.05million ton per year, respectively. And the related standard emissions were7.76,62.34and45.23million ton per year. The average concentrations of COD, TN and TP emitted from NPSP were6.25,2.53and0.36milligrams per liter in Jiangsu, respectively. The concentrations of these pollutants in different regions of Jiangsu Province were in the order north region> center region> south region.The mean value of comprehensive water quality index (CWQI) of Jiangsu Province is2.10, reaching the moderate pollution state. As for the different cities in Jiangsu province, the comprehensive water quality index of Xuzhou, Suqian, and Lianyungang all reached serious pollution state; For Huaian, Yancheng, and Taizhou, the comprehensive water quality index reached moderate pollution state; and for Nantong and Yangzhou, it was light pollution. In contrast, Nanjing arrived at the state of alert. Wuxi, Changzhou, Suzhou and Zhenjiang were in a safe state.The main pollutants were TN and TP with the contribution of54.71%and38.86%in Jiangsu, respectively. The main pollution sources were chemical fertilizer, livestock and poultry breeding, human excrement and urine, aquiculture, with the contribution of30.75%,24.94%,16.85and15.28%, respectively. The agricultural production value is the highest degree of correlation and pollutant emission factor in land area, agricultural production and rural population of several major factors.The results of cluster analysis on the coefficients of "Pressure"and"state" showed that the spatial distribution of "Pressure" consisted with the spatial distribution of’state".According to the control area method, Jiangsu Province is divided into four A level (Contamination sensitivity)and ten B level(The type of pollution, pollution control direction).Conduct load shedding distribution of ANPSP separately by region, pollutants and pollution sources on the basis of accounting water environment capacity of ANPSP in Jiangsu.On the basis of the results of analysis and research, presented control countermeasures in light for the main ANPSP source.