Artificial cultivation of biological soil crust and its effects on soil and water conservation in water-wind erosion crisscross region of loess plateau, China

Chinese. 探讨生物结皮的人工培育技术，并对其发育初期的水保功能进行评价。结果表明：撒播粉碎后的自然生物结皮，培育1个雨季即可形成盖度高达30％～60％的人工生物结皮，其主成分不变；人工生物结皮具有较好的水保效应，其中室内培育的生物结皮在坡度5°、雨强46．8mm・h. 1、历时1h的模拟降雨条件下可减少49％～64％的径流，消除土壤侵蚀；同条件下野外培育的生物结皮在无植被时对径流影响不明显，但全年可减少26％的土壤侵蚀，有柠条植被时全年可减少11％的径流和39％的土壤侵蚀；在黄土高原侵蚀区以人工生物结皮进行大规模的水保治理成本较低，切实可行。

English. Biological soil crust （BSC） is one of the most important vegetation components in arid and semi arid areas and has very important ecological functions which attract more and more attentions to its effects on soil and water conservation. In summary, there are three different opinions about the effect of BSC＇s on infiltration： increase, decrease, and no function. In order to explore artificial cultivation method of BSC and evaluate its effects on soil and water conservation, BSC was artificially cultivated in laboratory and field in water-wind erosion crisscross region of loess plateau, China and the runoff and sediment were measured during the simulated rainfall in laboratory and after natural rainfall in field. The results show： 1. It was feasible to inoculate and cultivate artificial BSC using the method of crushing and broadcast sowing natural BSC collected from research areal 2. The artificial BSC＇s coverage reached to 30~60% af ter a rainy season and the main components was same to natural BSC~ 3. The artificial BSC had obvious function of soil and water conservation. The artificial BSC in the laboratory decreased 49 %-64% of runoff and eliminate soil erosion and in field had no significant effects on runoff and decreased 26% of sediment in the plot without vegetation, decreased 11% of runoff and 39% of sediment in the plot with Caragana korshinskii Kom. , respectively. Those results confirm that it could be effective to cultivate artificial BSC and use it to control the loss of soil and water in research area.