The Distribution of Agricultural Non-point Source Pollution in Hunan Rural Area

In order to reveal the distribution of agricultural non-point source pollution in Hunan rural area, the producing amount and producing intensity of chemical oxygen demand (CODCr), total nitrogen (TN) and total phosphorus (TP) of 14 pastoral prefectures in Hunan province were calculated by inventory analysis approach, and the spatial-temporal distribution and main causes were analyzed. The results showed that the producing amount of CODCr, TN and TP in Hunan rural environment increased from 3 563.34×104,188.46×104 and 35.96×104 tons to 4 361.13×104, 216.58×104 and 43.21×104 tons from year 2002 to 2011. The producing intensity of CODCr TN and TP increased from 1 688.76, 89.32 and 17.04 kg/hm2 to 2066.86, 102.64 and 20.48 kg/hm2 from year 2002 to 2011. Agricultural non-point source pollution spots with the highest producing intensity in Hunan rural area distributed in Changde, Shaoyang, Hengyang and Yongzhou. In the process of agricultural production, the development of livestock and poultry breeding industry and fertilizer application were main reasons that led to the generation of agricultural non-point source pollution in Hunan rural settlement, the contribution of domestic sewage was relatively low.