Abstract:

The intensity of nitrogen cycling in vegetable crop-soil system is high and the amount of nitrogen losses is great with various losing ways because of the excessive fertilization. In this paper, the status were summarized. The processes and the quantity feature of soil nitrogen input, interior transformation and output, including fertilization, atmosphere desposition, ammonification nitrogenfixation, ammonification, nitrification, denitrification,plant uptake, nitrogen accumulated, NH3 volatilization, runoff and NO3- leaching were introduced. The environmental effects of nitrogen loss were carried out.