Effect of Reverse-slope Level Terrace on the Nitrogen Contents of Sloping Farmland in Songhuaba Reservoir

In order to reasonable utilization of slope land, and preservation of fertility, this study set standard reverse-slop level terrace in the watershed runoff plots within planting, for finding the dynamic variation of the soil nitrogen content of reverse-slop level terrace. Researches show that nitrogen loss, surface runoff and sediment yield correlated significantly, the reduction rate of the higher antislope to surface runoff was 9.68%-36.84% and the average reduction rate was 23.54 percent, and the reduction in soil erosion was 40.98%-71.68%, with an average reduction rate of 56.62%; After the rainy season, the level of soil nitrogen content is 53.97% higher than that of the higher anti-slope; The reduction rate of nitrogen was 42%, the reduction rate of nitrogen was 25%, and the difference was significant. It shows that the reverse-slop level terrace can effectively reduce the loss of nitrogen, keep the nitrogen content of the soil, and reduce the soil loss caused by the runoff of land surface runoff.