阴山北麓残茬间作带田土壤风蚀规律

Wind Erosion Law in Strip Intercropping Field in North Yin-shan

为了探究带状间作农田残茬带宽度对土壤风蚀模数的影响,进一步验证野外移动式风洞对研究区带田土壤风蚀模数进行的原位测试结果,采用风蚀圈和陷阱诱捕的方法对研究区土壤风积和风蚀情况进行监测。风积量结果表明,不同宽度莜麦残茬带宽小于6m时,风积量随带宽增加而减小,带宽6～10m风积量随带宽增加而增加,带宽大于10m后风积量开始下降;与残茬带等宽间作裸地中,随带宽加大风积量不断降低,带宽在3.6m左右时达到最低值,带宽大于3.6m后风积量随带宽增加而不断增加。风蚀量结果表明,不同宽度莜麦残茬带中,5m带宽内土壤风蚀量显著降低,5～10m范围缓慢上升,带宽超出10m土壤风蚀量又呈现稳中有降的变化趋势;不同带宽间作裸地中,土壤风蚀量基本在带宽3m之内呈直线下降,带宽在3m左右时土壤风蚀量最低,带宽在3～7m时土壤风蚀量呈直线上升趋势,在7～10m时土壤风蚀量基本保持稳定,带宽大于10m后土壤风蚀量又呈直线上升趋势;不同带宽残茬+等宽秋翻地的土壤风蚀量变化规律,基本与间作裸地的变化趋势相同;不同带宽间作裸地带中不同位置土壤风蚀量随距莜麦残茬距离的增加而增大。

The method of wind erosion ring and pitfall tripping were used to observe the effect of strip width on the wind erosion modulus and verify the results received by field mobile wind tunnel. The wind erosion and wind-blown quantity were determined and the results showed that wind-blown quantity was decreased when the width was narrower than 6 m and increased with the increasing of strip width when the width was 6-10 m, and decreased when the width was wider than 10 m in the stubble of naked oat. The wind-blown quantity decreased with the increasing of strip width in naked field when the width was less than 3.6 m, and increased when the width was wider than 3.6 m. The wind erosion quantity was decreased significantly in the stubble of naked oat when the width was less than 5 m, and increased when it was 5-10 m and decreased slowly when the width was wider than 10 m. The wind erosion quantity decreased with the increasing of strip width in adjacent naked field when the width was less than 3 m, and increased sharply when the width was 3 -7 m and kept stable in 7-10 m then increased sharply again when the width was wider than 10 m. The wind erosion changed similarly in combination of keeping stubble and same width naked field as in the adja- cent naked field, the wind erosion was increased with the distance to oats stubble increasing in the naked field of different width intereropping field.