残茬和秸秆覆盖对黄土坡耕地水土流失的影响

Effect of stubble and straw mulch on soil and water erosion on loess slope land

通过田间试验与实验室模拟降雨试验,研究了残茬和秸杆覆盖对黄土坡耕地水土流失的影响。结果表明:坡耕地覆盖具有保水保土、减少土壤侵蚀的效果,而且随着覆盖量与覆盖年限的增加,效果更明显;在雨强为80、100mm/h模拟降雨条件下,与不覆盖相比,泥沙侵蚀率分别减少了97.8%与98.8%,溅蚀几乎没有,降雨入渗增加2.12倍和1.87倍,同时大幅度降低了侵蚀沉淀中氮和钾的浓度及土壤氮、钾总流失量。与基础土壤比较,侵蚀沉淀中氮钾具有养分富集作用。

The research was conducted to investigate the effect of stubble and straw mulch on soil and water erosion on loess slope land by field test and rainfall simulation experiment in lab. The results showed that the mulch on slope land was effective to conserve soil and moisture and reduce erosion, and the effect was more remarkable as the increase of amount and years of mulching. Under the condition of rainfall simulation (80 mm/h, 100mm/h), compared to bare land, stubble and straw mulch decreased soil erosion by 97.8% and 98.8%, avoided splash erosion, and increased water percolation rate by 2.12 and 1.87 times respectively. Mulch also reduced content and loss of N and K in erosion sediment, and enriched the nutrient of N and K in the soil. \;