Effect of Nitrogenous Fertilizer Modality on Soil Nutrient Loss of Sloping Land in Rainy Season

In order to discuss the effects of nitrogen forms on soil nutrient loss fluxes and approach,we used randomized block experiment design,under simulated runoff observation method to study the effect of nitrogen forms and mulching on soil nutrient loss fluxes and approach in slope land. The results showed that the interflow loss of nitrogen,phosphorus and potassium was 71.30%,6.36% and 8.85% respectively of the total runoff. It indicated that the main way of phosphorus and potassium loss in the runoff was surface runoff,but the main way of nitrogen loss in the runoff was interflow. The nitrogen loss of amide nitrogen fertilizer and controlled release fertilizer was reduced by plastic mulching,the interflow nitrogen concentration and nitrogen loss quantity of amide nitrogen fertilizer by plastic mulching was reduced 40.40% and 29.32% compared with no mulching. On no mulching,the total nitrogen loss of runoff was given as follows: amide nitrogen fertilizerammonium nitrogen fertilizercontrolled release fertilizernitrate fertilizer,the nitrogen loss was minimum by nitrate nitrogen fertilizer on no mulching,it was 40.86% fewer than that of using amide nitrogen fertilizer. On plastic mulching,the total nitrogen of runoff was given as follows: ammonium nitrogen fertilizeramide nitrogen fertilizernitrate fertilizercontrolled release fertilizer,the nitrogen loss was minimum by slow controlled release fertilizer on plastic film mulching conditions,it was 59.60% fewer than that of using ammonium fertilizer. In order to effectively control water and soil nutrient loss of purple hilly area in Sichuan Province,we recommend using nitrate nitrogen in bare soil conditions and using controlled release fertilizer in the plastic mulching conditions.