摘要
为探究秸秆覆盖免耕对坡耕地土壤理化性质的影响及该措施下的水土保持效益.通过设立秸秆覆盖免耕和传统耕作田间试验区,探究土壤孔隙结构、土壤含水量、化学性质、产流产沙情况.结果表明:秸秆覆盖免耕处理后,土壤深度(h)为 0＜h≤10 cm处土壤密度增加了 14.16%,总孔隙度及非毛管孔隙度分别降低了 10.85%、27.11%.土壤深度为 0＜h≤20 cm处土壤有机质及全氮流失量减少,有效改善了土壤养分含量及分布.土壤深度为 10、20、30、40 cm处土壤含水量分别提高 6.30%、5.78%、7.57%、9.03%.在相同降雨条件下,土层越深土壤水分滞留时间越短.秸秆覆盖免耕处理减弱了降雨侵蚀力对产流产沙的影响,产流产沙次数及数量较传统耕作处理有明显降低,产流、产沙次数分别减少 3、5 次,产流、产沙量分别减少 53.07%、71.87%.秸秆覆盖免耕能够有效降低降雨对产流产沙的驱动力,减少土壤有机质及氮流失,调节土壤结构.
Abstract
To investigate the effects of straw mulching combined with no-till farming on the physicochemical properties of soil and the benefits of soil and water conservation,field experiments were established comparing straw-covered no-till and tradi-tional tillage practices.The study examined soil pore structure,soil moisture content,chemical properties,as well as run-off and sediment yield.The results showed that,following the straw mulching and no-till treatment,soil density at a depth of 0＜h≤10 cm increased by 14.16%,while the total porosity and non-capillary porosity decreased by 10.85%and 27.11%,respectively.At the depth of 0＜h≤20 cm,the loss of soil organic matter and total nitrogen was reduced,which effectively improved soil nutrient content and distribution.Soil moisture content at depths of 10,20,30,and 40 cm in-creased by 6.30%,5.78%,7.57%,and 9.03%,respectively.Under the same rainfall conditions,the deeper the soil lay-er,the shorter the soil moisture retention time.The straw mulching and no-till treatment weakened the impact of rainfall erosion on runoff and sediment yield,with a significant reduction in the frequency and quantity of runoff and sediment com-pared to traditional tillage.The number of runoff and sediment events decreased by 3 and 5 times respectively,while the amounts of runoff and sediment decreased by 53.07%and 71.87%.Overall,straw mulching combined with no-till farming effectively reduces the driving force of rainfall on runoff and sediment yield,minimizes the loss of soil organic matter and nitrogen,and helps regulate soil structure.
维普
万方数据