Research on Nitrogen Budgets of Agricultural Fields of the Tao River Basin
Based on a nitrogen (N) budget change model of agricultural fields, nitrogen budget change in each county in Tao River basin was calculated. For the whole basin, N-inputs, N-outputs and N-surpluses were obtained. The results indicated that N-inputs and N-outputs of Tao River from 2006 to 2008 increased obviously. The total N-inputs (N-outputs) in 2006, 2007 and 2008 were 31935 (18109) Tg, 33162 (17982) Tg and 33878 (19048) Tg, respectively. Compared the sources of N inputs, chemical fertilizer accounted for 44.94%, followed by human and animal excreta with 26.06%. For the N-outputs, the percent of crop harvest was biggest with 49.36%. N surpluses were 13826 Tg yr-1 in 2006, 15179 Tg yr-1 in 2007 and 15829 Tg yr-1 in 2008g. Annual growth rates were 9.9% in 2007 related to 2006 and 4.3% in 2008 related to 2007. The N-budgets with positive values showed that it increased significantly. Therefore, it was very urgent to control the non-point source of nitrogen pollution in Tao River basin.
Zhenyu Du and Chengbin Li
Z. H. Zhao and Z. M. Qiu, "Research on Nitrogen Budgets of Agricultural Fields of the Tao River Basin", Advanced Materials Research, Vol. 281, pp. 237-242, 2011