Abstract:

Anhui,being one of the major agricultural provinces in China, is faced with a series of environmental problems, of which nonpoint source pollution from chemical fertilizationin farmlands is one. In order to better understand the potential threats of fertilization to the rural ecosystem and agricultural sustainable development in Anhui Province, China, environmental risk assessment (ERA) of fertilization was conducted. An index model for environmental risk assessment of nonpoint source pollution from fertilization was established and spatio-temporal variation of fertilization and environmental risk of non-point source pollution from fertilization in Anhui was analyzed. Results show that in Anhui of 2013, the total chemical fertilization intensity was 853.6 kg·hm^-2 on average; the environmental risk index of the non point source pollution from chemical fertilization was 0.72; the total environmental pollution risk ranked moderate; N:P:K in fertilization was 1:0.52:0.49; the environmental risk index of N, P and K single-element fertilizers was 0.72, 0.78 and 0.65, respectively; the environmental risk of the three kinds of single-element fertilizers ranked moderate, serious and light, respectively; and their spatio-temporal distribution displayed an obvious aggregation effect. In the 16 prefecture-leveled cities, the problem of excessive fertilizationin farmlands existed universally. Though varying sharply from region to region in severity, it displayed a specific pattern of distribution. Environmental risk was very serious in Huainan, serious in Bengbu, Lu′an, Wuhu and Tongling, and moderate in the rest of the cities.

Key words: non-point source pollution, fertilization intensity, ecological safety standard, environmental risk index, Anhui Province