中文摘要：

土壤抗侵蚀能力对土壤侵蚀的发育有重要影响,土壤抗蚀性是评价土壤抗侵蚀能力的重要参数之一。黄土高原土壤侵蚀普遍发生,研究黄土区坡耕地土壤抗蚀性特征对于该地区实现可持续发展有重要意义。通过室外采样与实验室分析相结合的方法,对黄土区不同生长期大豆坡耕地的抗蚀性特征进行研究。研究结果显示土壤抗蚀性指数在苗期-结荚期增长较快,并于始粒期达最大,在始粒期-鼓粒期均逐渐降低。0-5 cm土层土壤抗蚀性最强,〉10-20 cm土层抗蚀性最弱。开花期、结荚期、始粒期与鼓粒期,〉5-10 cm土层土壤抗蚀性最强,〉10-20 cm土层最弱。这表明土壤抗蚀性与大豆生长以及根系在土壤内分布状况关系密切,随着大豆的生长,其根系渐趋发达,固土能力变强,始粒期之后植株由营养生长转向生殖生长,根系生长逐渐停止并开始衰减,土壤抗蚀性减弱。但不同深度土壤的根系含量不同,导致不同深度土壤的抗蚀性有所差别。

英文摘要：

Soil anti-erodibility is one of the main factors affecting the development of soil erosion. The wide distribution of soil loss on slope farmland in hilly loess region restricts the development of the local economy and the improvement of people＇s living standard seriously. As one of the most severe soil erosion areas in china, it is especially important to research soil anti-erodibility characteristics of loess hilly region for soil erosion prevention and control. Therefore, a field experiment is conducted to determine the soil anti-erodibility characteristics during the growing stages of the soybean. Soil anti-erodibility index can reflect the characteristics of anti-erodibility effectively. Soil anti-erodibility index increases significantly from the seedling stage to the bearing pod stage, reaches the maximum value at seed generative stage, and decreases progressively from the seed generative stage to the seed-filling stage. The results show that the soil anti-erodibility of 0- 5 cm layer is the best and of 〉 10 - 20 cm layer is the worst from the seedling stage to the branching stage. But the soil anti-erosion ability of 〉5- 10 cm layer is the best and of 〉10-20 cm layer was the worst from the blooming stage to the seed-filling stage. It shows that soil anti-erodibility index may be closely related to the root distribution characteristics in soil. Soil anti-erodibility will be enforced with the increasing contents of roots in soil.