中文摘要：

为改善生物结皮对土壤水分的负面影响,通过野外定位观测试验,从水分入渗、产流产沙两方面探讨黄土高原水蚀风蚀交错区生物结皮在3种翻耙强度下的水土保持效应.结果表明：（1）相比裸土,生物结皮对入渗和径流的表现形式并非单一的增加或减少,在雨季初期增渗减流,随雨季推进入渗减少,径流增加;（2）翻耙生物结皮促进入渗,减少径流.同裸地对照相比,轻度翻耙结皮增渗15.o％,减流22.6％,中度翻耙结皮增渗36.6％,减流29.3％,重度翻耙结皮增渗14.4％,减流9.6％;（3）翻耙生物结皮对泥沙量有显著影响.与裸地相比,轻度翻耙结皮减少泥沙量54.8％,中度翻耙结皮减少泥沙量45.5％,重度翻耙结皮减少泥沙量1o.4％.综合考虑入渗和土壤侵蚀认为,轻度、中度翻耙生物结皮可以在不明显增加土壤侵蚀的前提下,促进入渗,减少径流,改善土壤水分状况.

英文摘要：

In order to improve the effects of biological soil crusts on soil moisture condition, we studied the soil and water conservation effects of biological soil crusts（BSCs） from two aspects（water infiltration and yield of runoff and sediment） under 3 harrowing intensities in the wind-water erosion crisscross region on the Loess Plateau, based on located field observation. The results were as follows： （1）Compared to impacts of bare soil, effects of BSCs on water infiltration and runoff showed temporal variations, which increased infiltration and decreased runoff at the early stage of rainy season, while showed an opposite effects in the later period of rainy season. （2） The harrowing BSCs reduced runoff and increased water infiltration. Compared to the control treatment（bare soil）, mild-harrowing BSCs reduced runoff by 22.6% and increased infiltration by 15.0 % while moderate-harrowing BSCs reduced runoff by 29.3% and increased infiltration by 36.6% and severe harrowing BSCs reduced runoff by 9. 6% and increased infiltration by 14.4%. （3）The harrowing BSCs had significant effects on sediment. Compared to the control, mild-harrowing BSCs reduced sediment by 54. 8%, moderate harrowing BSCs reduced sediment by 45. 5% and severe-harrowing BSCs reduced sediment by 10.4%. Considering the changes of infiltration and soil erosion, we can conclude that BSCs with mild and moderate harrow intensity could promote infiltration, reduce runoff and improve soil moisture conditions without leading to obvious increases of soil erosion.