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以青海黄土丘陵区18条侵蚀沟为研究对象,用钢钎法测定了侵蚀模数,根据样地土壤砂粒、粉粒、粘粒质地分布和有机质的质量分数,分析计算其可蚀性K值。结合样地植被、坡度等调查信息,分析侵蚀模数与其影响因子的关系。结果表明:同一时期,侵蚀模数随植被覆盖度的增加而降低,当植物覆盖度达到70%时,侵蚀模数对植被因子的敏感度降低。侵蚀模数随土壤孔隙度的增大而降低。随K值的增大和坡度的升高,侵蚀模数有增大的趋势。不同时期,高植被覆盖的样地,侵蚀模数随年限的增加呈降低趋势;低植被覆盖的样地,侵蚀模数随年限的增加呈波动变化,但总体上呈下降趋势;无植被覆盖的侵蚀沟样地,年侵蚀模数没有降低趋势。植被覆盖度相当的样地,K值越小,侵蚀模数越小。
Erosion modulus was determined by using steel brazing method in 18 erosion gully sections of loess hilly region of Qinghai Province. According to the distribution of soil grit, silt and clay, and the mass fraction of organic matter in the sample soil, the erodibility K . According to the survey information such as sample vegetation and slope, the relationship between erosion modulus and its influencing factors was analyzed. The results show that the erosion modulus decreases with the increase of vegetation coverage in the same period. When the vegetation coverage reaches 70%, the sensitivity of erosion modulus to vegetation factors decreases. Erosion modulus decreased with the increase of soil porosity. With the increase of K value and the increase of slope, the erosion modulus tends to increase. In different periods and high vegetation cover plots, the erosion modulus decreased with the increase of years. In the low vegetation cover plots, the erosion modulus fluctuated with the increase of years, but decreased in general; Erosion ditch sample, the annual erosion modulus did not reduce the trend. With a similar vegetation coverage, the smaller the K value, the smaller the erosion modulus.