Author(s)

Xinyan Li¹, Hengpeng Li^1*, Guishan Yang¹, Nkotagu Hudson², Huan Zhang³, Xiaofei Nie¹

¹Key Laboratory of Lake and Environment, Key Laboratory of Basin Geology, Chinese Academy of Sciences, Nanjing Institute of Geography and Limnology, Nanjing, China.
²Department of Geology, University of Dar es Salaam, Dar es Salaam, Tanzania.
³School of Geographic and Oceanographic Sciences, Nanjing University, Nanjing, China.

Based on agricultural nitrogen (N) balance model and field experiments, the impacts of farming system changes of Taihu Region of China on surface water environment were studied. During past 60 years, farming systems changed greatly in Taihu Region. The traditional method of manure collection and application was replaced by chemical fertilizer utilization gradually. Chemical N fertilization intensity decreased greatly due to the abolition of “3 crops per year” and reduction of cropland area in 1990-2010. Crops depleting soil fertility increased, while those improving soil fertility decreased, leading to an excessive dependence on chemical fertilizer application, which increased the risks of soil N loss to surface water environment in Taihu region. However, field experiments showed that the agricultural N loss with runoff only accounted for 2% of fertilizer N application rate. The majority of N was exported by crop harvesting. Our findings showed that the agricultural N loss might not be the main source of N pollution in Lake Tai after 2000. To control N pollution of Lake Tai, more attention should be paid to industrial and domestic wastewater from urban and rural areas, wastes from livestock and poultry breeding, bait input for aquaculture, etc in the Taihu Region, China.

Farming Systems, Agricultural Nitrogen Balance, Fertilization, Environmental Pollution, Taihu

Li, X. , Li, H. , Yang, G. , Hudson, N. , Zhang, H. and Nie, X. (2015) Variations of Farming Systems and Their Impacts on Surface Water Environment in Past 60 Years in Intensive Agricultural Area of Taihu Region, China. Journal of Water Resource and Protection, 7, 647-658. doi: 10.4236/jwarp.2015.78053.