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以土壤风蚀严重的河北坝上康保县为研究区,采用风洞试验的技术手段,对农田耕作方式与土壤风蚀强度的关系进行研究。结果表明,农田留茬与翻耕、农田垄向及农作物残茬高度的差异对土壤风蚀强度有较大影响。垄向平行主风向的风蚀强度大于垄向垂直主风向的风蚀强度。风速越大,垄向不同造成的风蚀强度的差异越大,尤其是当风速≥15m/s时,风蚀强度的差异表现得较为明显;风蚀强度与留茬高度呈负相关;翻耕地的风蚀强度大于任何留茬地的风蚀强度;风蚀强度与风速变化呈现出指数函数变化规律。因此,农田垄向垂直主风向、作物收获后不进行翻耕、留有适度茬高、优先种植残茬硬度较大的莜麦作物,这样的耕作方式可有效降低土壤风蚀强度,缓解河北坝上地区农田土壤风蚀状况。
Taking Kangbaoxian County, Hebei Province, as the research area, the wind tunnel test was used to study the relationship between farmland cultivation mode and soil wind erosion intensity. The results showed that the differences of stubble and tillage, farmland ridge and crop stubble height had a greater impact on soil erosion intensity. The wind erosion intensity of the main wind direction parallel to the ridge is greater than the wind erosion intensity of the main wind direction of the ridge. The greater the wind speed, the greater the difference of wind erosion intensity caused by different ridge, especially when the wind speed is more than or equal to 15m / s, the wind erosion intensity is more obvious; the wind erosion intensity is negatively correlated with the stubble height; Which is greater than that of any stubble area. The change of wind erosion intensity and wind speed showed exponential function. Therefore, the farmland dominates the vertical main wind direction, no tillage is carried out after the harvest of the crops, moderately high stubble remains and priority is given to planting barley crops with relatively high hardness of stubble. Such tillage methods can effectively reduce the wind erosion strength of soil and alleviate the erosion of Hebei dam Regional farmland soil erosion status.