针对云南省典型丘陵区有机茶园管理措施，利用坡面土壤侵蚀机理模型———水蚀预报模型（WEPP），模拟了提高植被覆盖率与秸秆覆盖量对坡面土壤侵蚀的影响。结果表明，无论是常规茶园还是有机茶园，降雨强度显著影响坡面土壤流失量和泥沙输出量；但坡长不是主要影响因子。秸秆覆盖使得土壤表层养分含量明显增加，同时也明显降低土壤侵蚀量，特别是在大暴雨和特大暴雨情况下，下降程度更明显；当秸秆覆盖量提高至1�0 kg · m－2时，土壤侵蚀量明显降低。模拟结果表明，随着有机茶园植被覆盖率的增加，土壤侵蚀量有所降低。对不同植被覆盖率和秸秆覆盖量组合效应的模拟结果表明，不同管理措施的综合作用对土壤流失量和泥沙输出量有明显减缓作用，特别当有机茶园覆盖率低的情况下，秸秆覆盖对土壤侵蚀的减缓作用更明显。%A study was carried out in a typical hilly region in Yunnan Province in order to investigate effects of organic farming measures for management of tea plantations on soil erosion. A water erosion prediction project(WEPP) model spe⁃cific for mechanism of soil erosion on slopes was used to simulate effects of higher vegetation coverage and/or higher straw mulching rate on soil erosion on slopes. Results show that rainfall intensity is the major factor, rather than slope length, significantly affecting soil loss and sediment output in either conventional or organic tea plantation on slope. Straw mulching significantly increases soil nutrient contents in the surface soil layer, and at the same time reduces soil erosion rate remark⁃ably, and the soil conservation effect is more obvious, especially in the cases of heavy rain shower and rainstorm. Soil ero⁃sion rate drops significantly when straw mulching rate reaches 1�0 kg·m-2 . The simulation shows that soil erosion rate re⁃duces with increasing vegetation coverage. The simulation of combined effect of vegetation coverage and straw mulching in⁃dicates that the combination of different management measures can significantly reduce soil erosion and sediment yield, es⁃pecially in tea plantations with low vegetation coverage, where the effect of straw mulching is more obvious.
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