Nutrient Restoration Effect And Water Erosion Precention And Control Of Slope Farmland Of Conservative Tillage Loess Plateau In Northern Shaanxi

The loss of soil erosion is the main type in the range of agricultural disaster in the Loess Plateau.In northern Shannxi,the dual role of water and wind erosion is a major agricultural disaster causal factors, which make local soil dry and water losing caused by soil erosion,thus exacerbating the disaster.In this study of conservation tillage on soil in sloping recovery effect and reduce erosion effects, based on traditional operating six tillage experimental plots: CK, No-tillage(NT), Straw mulching(SM),plastic film mulching(PM),Ridging and plastic film mulching(RPM),Interplant(In) are set on sloping land in the Shenmu Liudaogou basin. To use the methods of Positioning monitoring and Statistics, studied the moisture and nutrients of different tillage patterns, revealed the corrosion proof and controllable effects. And chose seven evaluative indexes and use the BP neural network to study the impact evaluation on different tillage. There are five conservation tillage patterns provided by the study. This study provides the basis for a reasonable selection of different cropping patterns in the Wind-Water Erosion Crisscross Region, in order to achieve healthy and sustainable development of agriculture in the region.(1) In natural fertility conditions, conservation tillage can increase the organic matter and total nitrogen content of the sloping land, soil fertility, lower bulk density, but mulching will cause an increase in soil bulk density. Straw mulch and pastoral intercropping can effectively improve soil organic matter and total nitrogen and have a strong effect in maintaining fertilizer.(2)Coverage can increase the surface soil moisture and inhibition of rain water loss, especially straw mulch has a distinct role in the increase in the plow layer soil moisture, keep the deep water, to prevent rain water loss. No-tillage after rain to keep the plow layer soil moisture effect is obvious. Plastic film mulching, and ridge mulching can increase the water use efficiency, but in the case of little precipitation, the film, however, reduced water infiltration.(3)And Water Conservation Effect of intercropping and covered ridge mode optimal, the other mode effects are lower than CK. In pastoral intercropping, alfalfa and soybeans competition for water, fight fat more obviously, seriously affecting the growth of soybean; ridge mulching pattern, soil and water conservation effect is obvious, but need reasonable choice of plastic film, contour ridging need to consider the height and slope of the ridge.(4) Mulching, straw mulching and no-tillage increase production, and intercropping decrease. It should be noted that, in the absence of artificial fertilizers put into the case, covered ridge can improve the efficiency of water and fertilizer use, but year after planting the reduced crop production is still very obvious.(5)Following the characteristics of water-wind erosion crisscross region and the evaluation of the principle of selecting, screen and establish the index system. Relying on BP neural network analysis, the comprehensive evaluation level of water-wind erosion crisscross region of conservative tillage sloping land is:In> SM> PM> RPM> NT>CK.