Evaluation of the present situation of the environmental impact in the intensive agriculture, and it's restoration at the inland of Western China

本研究以云南省滇池东南沿海集约化农业区为研究对象。大多数农民每年种植六七种作物。这种非常高的种植强度是基于生长期短的蔬菜和移栽栽培的结合。然而，在许多集约化种植领域，施用的养分量超过了作物需求。(2)土壤中N、P、K浓度随化肥输入比粪肥输入增加的幅度更大。减少氮、磷、钾的投入比增加它们的产出对环境影响的恢复更有效。(3)在人工湿地中，芦苇的收获影响了地上部的再生和根垫的硝化和反硝化活性。

This study was performed in the intensive agricultural region in the coastal area of southeast Lake Dianchi, Yunnan province, China. (1) Most farmers cultivated six or seven crops per year. This very high cropping intensity is based on the combination of vegetables with a short growing duration and transplanting culture. However, the amount of applied nutrient exceeds crops demand in many intensive cropping fields. (2) The concentrations of N, P, and K in soil increase to a larger extent with input of N, P, and K from chemical fertilizers than from manure. Reducing the input of N, P, and K would be more efficient than increasing their output for restoration of the environmental impact. (3) In constructed wetland, harvest of reed affects the aboveground regrowth and nitrification and denitrification activity of the root mat.