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

中国，本研究是在云南省滇东南沿海集约化农业区进行的。(1)大多数农民一年种植六七种作物。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相结合的基础上的。然而，在许多精耕细作的田地里，养分的施用量超过了作物的需求。(2)土壤中N、P、K浓度随化肥N、P、K投入的增加幅度大于有机肥。减少N、P、K的投入比增加N、P、K的产出更有效地恢复环境影响。(3)在人工湿地中，芦苇的收获影响根席的地上再生长和硝化反硝化活性。

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.