中文摘要：

基于野外调查在室内采用模拟降雨和径流冲刷相结合的试验方法,研究沟头秸秆覆盖措施对黑土区不同阶段侵蚀沟发育的影响.结果表明：两种沟蚀发育阶段下,与沟头无秸秆覆盖处理相比,沟头秸秆覆盖处理的坡面总侵蚀量分别减少67.5％和76.7％,沟蚀量分别减少了72.3％和69.1％.随着沟蚀发育程度的增加,坡面总侵蚀量,沟蚀量和沟蚀比例呈现降低趋势.沟头秸秆覆盖使两种沟蚀发育阶段的沟内集中水流流速减小而阻力系数增加,对应的沟间薄层水流流速增加而阻力系数减小,相应的雷诺数和佛汝德数变化特征与流速相同.沟头秸秆覆盖对汇入沟内的坡面径流的拦截与分散作用,减弱了侵蚀沟内集中水流的侵蚀和搬运能力,从而有效防治了沟蚀的发育.因此,在东北黑土区推广沟头秸秆覆盖技术十分必要,尤其是在侵蚀沟发育活跃期应用这一技术会更好地发挥其防治沟蚀的效果.

英文摘要：

Based on field investigations, a combined experiment included rainfall simulation and runoff scour was conducted in the laboratory, to investigate the effects of corn straw mulch buffer in the gully head on the gully development of different stages in the black soil region of Northeast China. The results show that total soil loss reduced by 67.5~/o and 76.7% , and gully erosion reduced by 72.3% and 69. 1% in the straw mulch treatments compared with the no-straw mulch treatments in the two different gully development stages, respec- tively. The total soil loss, gully erosion and the ratio of gully erosion to total soil loss decreased with the in- crease of the gully erosion development degree. With regard to the corn straw mulch buffer treatments for the two gully development stages, the velocity of concentrated flow in gully reduced and the corresponding resist- ance coefficient increased, and the sheet flow velocity inter gully increased and resistance coefficient decreased compared with the no-straw mulch treatments. The corresponding Reynolds and Froude number had the same variation characteristics with the velocity. The interception and dispersion of the corn straw mulch buffer in the gully head to runoff, which imported into gully, made the erosion and transport capacity of the concentrated flow in gully weaken; thus, the corn straw mulch buffer in the gully head could prevent gully development effectively. In summary, there is necessary to promote the straw mulch technology in the black soil region of Northeast China, especially for the active stage of the gully development.