垦植方式对山地果园水土流失的影响

应用径流小区法，长期（1996-2006）定位研究福建中部尤溪县垦植方式对山地果园水土流失的影响，结果表明：1）该地区11年平均年降雨量1575.5mm，平均年蒸发量1461.1mm，5月、6月、8月是强降雨高发期，也是水土流失防治的关键期；2）在山地果园开发中，平台开垦的径流系数为0.0688，明显小于顺坡开垦（0.2865）；3）植草能使果园0-30cm土层的土壤含水量提高0.8％-0.9％；4）顺坡清耕区侵蚀模数为2388.2t／（km^2·a），梯台清耕区土壤侵蚀量达10.3kg/m，土壤侵蚀主要源于台壁受冲刷，顺坡植草区、梯台植草区基本不发生土壤侵蚀。

Effects of different exploitation manners on soil and water losses in hilly orchard

Youxi County is located in the middle part of Fujian Province and belongs to the mid-subtropical monsoon zone.From 1996 to 006,long-term observation was carried out to study the effects of 5 exploitation manners on soil and water losses.Results showed that the average annual rainfall in last decade was 1 575.5 mm,and the evaporation was 1 461.1 mm.The annual rainfall is mostly amassed in the first half of the year and the rainstorm of which occupies 11% of raining times and 50% of rainfall amount in the whole year.Strong rainfall frequently occurred in May,June,and August.During these periods,measure was needed to control soil and water losses.The land exploitation by building terraces had the higher function to avoid occurrence of runoff than that by down-slope.The coefficient of run off in terrace plots was 0.068 8,with obviously lower than down-slope plots(0.286 5).Green covering measure had high function to increase soil water content and to control soil erosion than clean tillage.The 0-30 cm soil water content in green covering plots increased 0.8%-0.9% than in clean tillage plots.Green covering plots was not found soil erosion,but in clean tillage plots,soil erosion was serious.For terrace exploitation,erosion was found on wall,annual erosion mount was 10.3 kg/m,and erosion modulus for down-slope exploitation was 2 388.2 t/(km²·a).