On average, the N import from precipitation in 2004-2006 accounted for 28.3% of the applied fertilizer N, suggesting that the N input from precipitation had greater effects on agroecosystem.

• 2004-2006年随降雨输入农田生态系统的氮平均占可利用肥料氮的28.；3%25，对农田生态系统有着重要影响。