Loess Area Conservation Tillage Anti-wind Erosion Wind Tunnel Simulation Experiment

Wind erosion has become one of the main problems to restrict agricultural developmentand environmental protection at the Loess Plateau in china, we need to protect the farmland inthe region urgently. Conservation tillage can make better the farmland soil environment,ameliorate soil fertility, improve agricultural production efficiency, increase farmers’ income,reduce and control of the farmland soil erosion. In order to describe and analyze the impact ofconservation tillage pairs of soil wind erosion objectively, in our study, we choose the LoessPlateau AnSai loess soil to do indoor wind tunnel simulation experiment. The main contentsof the experiment is to study the wheat straw mulch and erect stubble two kinds ofconservation tillage pairs of soil wind erosion, to establish farmland wind erosion model forthis region with experimental results and to verify the model. The main conclusions are:(1) Straw mulch and erect stubble can control the farmland soil erosion effectively. Winderosion intensity reduced of the exponential function with the increase in the degree of strawmulch. When the wind speed is6m/s and straw mulch is greater than3859kg/hm~2or windspeed is8m/s and straw mulch is greater than4210kg/hm~2, the wind erosion intensity issubstantially0. Wind erosion intensity decreased linearly with the straw erect stubble heightincreases. Whenever stubble height increased0.05m, anti-erosion efficiency is increased by atleast8.5%.(2) The anti-erosion efficiency of combination measures is better than the singlecoverage measures. The anti-erosion efficiency difference between combination measures andsingle coverage measures became smaller and smaller with the increase in the amount ofstraw mulch. When the straw mulch is4210kg/hm~2, the anti-erosion efficiency of combinationmeasures and single coverage measures are more than99%.(3) The amount of vertical wind erosion of different measures reduced with heightincreases in the range of0to62cm height.. The amount of wind erosion and the high degreeof change comply with a power function, soil particles are mainly concentrated in the range of0to36cm height. The straw mulch measures, erect stubble measures and combinationmeasures can effectively prevent the soil particles to rise and control more soil particles in thesurface. (4) For China’s Loess Plateau loess soil proposed wind erosion model for conservationtillage. According to wind speed, straw mulch and vertical stubble height, Simulated farmlandsoil erosion under different circumstances, providing the basis for the evaluation of this areaof conservation tillage on preventing soil erosion. By using indoor data test to prove that thewind erosion model analog values with indoor measured values have agree well, it canbasically reflect the process of farmland soil erosion.