采伐迹地清理方式对水土流失及更新苗木的影响

Impact of Slash Disposal on Soil and Water Loss and Growth of Planted Seedlings

定点观测研究表明，不同清理方式对迹地的水土流失及更新苗木的成活与生长的影响有很大差异，对未清理、带堆清理和火烧清理作了比较试验。火烧清理方式造成的水土流失与养分流失都大大超过未清理和带堆清理，但坡度小于１６°时，尚不至造成严重的水土流失，坡度大于２３°时，应禁止采用火烧法，这是火烧不利的一面。有利的一面是有助于提高造林成活率和促进更新苗木的生长。不论哪种清理方式，苗木成活率均随坡度的增高而降低。

The fixed observation showed that soil and water loss and growth of planted seedlings with differ-ent slash disposal methods were very discrepant on logged areas.The three methods of slash disposal in this ex-periment were no clearance, strip clearance and burning clearance. The results obtained from this study showedthat the soil erosion,water and nutrient loss were higher in burning clearance than those in no clearance andstrip clearance.Soil and water loss was not serious when the slope of logged area was under 16°. Burning clear-ance could not be used when the slope was over23°. Survival rate of the planted seedlings was higher and theirgrowth was better in burning clearance plots than in no clearance and strip clearance plots. No matter whichmethods of slash disposal being used,the seedling survival rate would drop aldng with the slope increasing.