摘要
通过对宁南黄土高原不同坡度、不同土地利用模式，坡面土壤侵蚀特征及相关影响因素进行分析，结果表明：不同土地利用方式下，土壤侵蚀量和径流量随坡度增加而增加，土壤侵蚀峰值均出现在6月，6月的径流量和泥沙量平均可达全年的29．42％、39．95％。土壤侵蚀量以农作利用方式最高，在14°30″下土壤侵蚀量是9°的4．05倍，自然荒坡土壤侵蚀量最低，只有农地利用模式的34．41％。相同坡度条件下，土壤侵蚀量表现为农地〉苜蓿＋沙打旺〉小冠花〉自然荒坡，但径流量和泥沙量的变化特征不一致。影响坡面土壤侵蚀的主要因子有次降雨量、雨强、降雨动能和降雨侵蚀力。各因子年间呈波形变动，以雨强和降雨侵蚀力变异幅度最大，可达35．79％～75．86％，次降雨量和降雨动能变异较小，只有25．72％～31．24％。降雨侵蚀力（R）呈单峰型分布，R（EI30）可以描述区域降雨侵蚀特征。在不同土地利用方式下，降雨侵蚀力和径流量、泥沙量之间没有明显相关，而径流量和泥沙量有一定的相关关系。
The factor effecting and soil erosion under the different gradient and land use pattern were studied on the Loess Plateau of the south Ningxia. The result showed that the fastigium of soil erosion were both on June,the amounts of runoff and sediment on June were nearly reach to 29.42% ,39.95% of whole year＇s. The runoff and the soil erosion were increased with the gradient increasing. The soil erosion were the highest under agriculture land use pattern, the amounts of soil erosion were 4.05 times under 14. 5 degree compared with 9 degree. The soil erosion under the natural sloping was the lowest , only about 34.41% of agriculture land use pattern. At the same gradient , the tendency of soil erosion were farming land use pattern〉 Medicago sativa L ＋ Astragalus adsurgens Pall 〉Coronila varia L〉natural sloping . The change of runoff and sediment were different. The mostly factor effecting of the soil erosion were hypo-rainfall, hypo-rainfall intensity, rainfall kinetic energy and rainfall erosivity. The change of mostly factor affecting were waved. Hypo-rainfall intensity and rainfall erosivity＇s variance index had a litter higher, were about 35.79 %-75.86 %. Hypo-rainfall and rainfall kinetic energy＇s variance index were lower, were about 25.72%-31.24%. The distribution of rainfall erosivity（R） were the single peak, EI3o also can be used to describe the rainfall erosivity of the Loess Plateau in the south of Ningxia. There were no obviously correlations between rainfall erosivity and runoff or sediment, but there were some correlations between runoff and sediment except for natural pattern.
出处
《水土保持研究》
CSCD
北大核心
2007年第1期7-10,共4页
Research of Soil and Water Conservation
基金
国家自然科学基金40401035
宁夏自然科学基金NZ0051资助
关键词
土壤侵蚀
影响因子
宁南黄土高原
soil erosion
effecting factor
the Loess Plateau of South Ningxia
