黄土丘陵沟壑区退耕地植物群落土壤抗蚀性能研究

Study on Erosion Resistance of Different Vegetation Communities in Abandoned Lands in Hilly and Gully Region on the Loess Plateau

以黄土丘陵沟壑区安塞县的纸坊沟小流域为例,对小流域内退耕地植被恢复后各群落土壤抗蚀性进行了研究,研究结果表明：（1）从土壤有机质含量指标讲,老荒坡和狼牙刺群落抗侵蚀能力最强,其次是刺槐、沙棘等人工林地,以猪毛蒿为优势种的群落和农耕玉米地抗侵蚀能力最弱;（2）从土壤团聚度、分散率和分散系数指标看,刺槐和黄刺梅群落抗侵蚀性能最强,农耕地和以猪毛蒿为优势种的群落抗侵蚀性能最差,人工林地和其它退耕还草地抗蚀性能居中;（3）从土壤生物结皮盖度讲,抗蚀性能为以茭蒿为优势种的群落〉以铁杆蒿为优势种的群落〉以猪毛蒿为优势种的群落;（4）从土壤侵蚀量来看,刺槐和沙棘群落抗侵蚀性能最强,以猪毛蒿为优势种的群落抗侵蚀性能最弱。综合分析得出抗蚀性能为：老荒坡,狼牙刺〉刺槐,黄刺玫,沙棘〉柠条〉白羊草,茭蒿〉铁杆蒿〉猪毛蒿,农耕地。随着退耕时间的延伸,退耕还林还草地的抗蚀性较农耕地不断提高,而与当地老荒坡群落的抗蚀性越来越接近。狼牙刺群落、刺槐和沙棘群落抗侵蚀性能最好,猪毛蒿群落群落抗侵蚀性能最弱,老荒坡各群落抗蚀性能较强,农耕地抗蚀能力有待提高。

The study on anti-erodibility of different vegetation communities in the Zhifanggou basin of Ansai county, a national experimental site in hilly and gully region on the plateau,shows that （1）From soil organic matter contents index, the anti-erodibility of native lands and Sophora viciifolia is among the best and then artificial forests which include Robinia psendoacacia and Hippophae chamnoides ,Artemisia scoparia and cropland are the weakest. （2） From soil aggregation degree and soil dispension degree and dispension coieffient index,Robinia psendoacacia and Rosa xanthina are among the strongest,Artemisia scoparia and cropland are the weakest. （3） From the coverage of biological soil crusts index,soil erosion resistance is Artemisia giraldii〉Artemisia gmelinii〉Artemisia scoparia. （4）From the amount of soil erosion index,Robinia psencloacacia and Hippophae rhamnoides are among the best,Artemisia scoparia is the weakest. In all soil erosion resistance is Sophora vicii folia 〉 Robinia psendoacacia ,Rosa xanthina , Hippophae rhamnoides 〉 Caragana intermedia 〉 Bothriochloa ischaemum , Artemisia giraldii 〉 Artemisia gmelinii 〉 Artemisia scoparia , cropland. The antierodibility of anandoned lands is getting stronger and stronger as the ages increase,approaching that of communities of native lands. The soil erosion resistance of Sophora viciifolia ,Robinia psendoacacia and Hippophae rhamnoides is the best,Artemisia scopari is the weakest, the soil erosion resistance of cropland is needed to be enhanced.