Preliminary analysis of the source reduced and sink increased for agricultural non-point source pollution by forest in Lake Taihu watershed:A case study of shelter belt in Yixing City

Abstract

To inquire the control effect of agricultural non-point source pollution by the shelter forest of Lake Taihu in Yixing City,the soil samples in the shelter forest belt were collected and the contents of nutrient elements were determined. Combined with the fertilization conditions of surrounding agricultural production,the source reduced and sink increased for agricultural non-point source pollution by the shelter forest in Yixing City was analyzed. The results showed that the C,N,P and K which were fixed by the shelter forest were 2439. 48,18. 34,2. 48 and 13. 42 g / m2 in October 2009,and 3114. 12,23. 42,3. 16 and 17. 13 g / m2 in May 2011,respectively. The fixed values showed a trend of gradually increasing,reaching to 4722. 46,35. 53,4. 81 and 25. 99 g / m2 in C,N,P and K in August 2013. The increased proportions of C,N,P and K were 93. 6%,93. 7%,94. 0% and 93. 7%respectively when compared with October 2009. The above results showed that the control effect of agricultural non-point source pollution by the shelter forest belt in Yixing City around the Lake Taihu coast was significant,and it had a big contribution to the management of water pollution in Lake Taihu.