水保所知识产出(1956---)知识库

采用人工模拟降雨试验，研究了踩踏干扰对生物结皮土壤渗透性的影响．结果表明:
踩踏干扰显著增加了土壤表面粗糙度，增加幅度与干扰强度有关，50%干扰度下表面粗糙度
指数较不干扰增加91%．踩踏干扰延长了坡面产流时间，20% ～ 50%干扰度范围内，随着干扰
强度的增加，初始产流时间呈线性增加趋势，50%干扰度的初始产流时间较不干扰增加了
169．7%．踩踏干扰增加了土壤渗透性，降低径流系数．50%干扰度的土壤累积入渗量较不干扰
增加12．6%; 去除生物结皮，土壤渗透性降低，累积入渗量较不干扰降低30．2%．50%以下的干
扰度未显著增加土壤侵蚀模数．去除生物结皮，土壤侵蚀模数较不干扰增加10 倍．生物结皮破
碎度低于50%的干扰在不明显增加土壤流失量的前提下，可增加降水入渗，减小径流风险，改
善土壤水分状况．

The effect of trampling disturbance on soil infiltration of biological soil crusts was investigated
by using simulated rainfall． The results showed that the trampling disturbance significantly increased
soil surface roughness． The increasing extent depended on the disturbance intensity． Soil
surface roughness values at 50% disturbance increased by 91% compared with the undisturbed
treatment． The runoff was delayed by trampling disturbance． A linear increase in the time of runoff
yield was observed along with the increasing disturbance intensity within 20%－50%． The time of
runoff yield at 50% disturbance increased by 169． 7% compared with the undisturbed treatment．
Trampling disturbance increased soil infiltration and consequently decreased the runoff coefficient．
The cumulative infiltration amount at 50% disturbance increased by 12．6% compared with the undisturbed
treatment． Soil infiltration significant decreased when biocrusts were removed． The cumulative
infiltration of the treatment of biocrusts removal decreased by 30．2% compared with the undisturbed
treatment． Trampling disturbance did not significantly increase the soil loss when the disturbance
intensity was lower than 50%，while the biocrusts removal resulted in 10 times higher in soil
erosion modulus． The trampling disturbance of lower than 50% on biocrusts might improve soil infiltration
and reduce the risk of runoff，thus might improve the soil moisture without obviously increasing
the soil loss．