小陇山林区抚育间伐对华山松人工林生长的影响

Effects of Tending Thinning on the Growth of Pinus armandii Plantations in Xiaolongshan Forest Region

通过样地设置调查和复测,分析了抚育间伐对小陇山林区华山松林木胸径、树高的生长和材积的影响,探讨了华山松人工林的间伐强度,间伐开始期、间隔期等间伐技术。结果表明,抚育间伐强度对华山松的平均胸径生长有极显著影响,但并不能促进华山松树高的生长;对该林分首次间伐基本是适宜的林龄为20a。第2次抚育间伐选择林分林龄为30a比较合适。间伐间隔期为10a;首次间伐时,林分保留密度为2 700株·hm-2,由此推算,并考虑林分的尽快郁闭和山区更新的实际情况,华山松人工造林初植适宜密度应为4 500株·hm-2。

Effects of tending thinning on the growth of the diameter at the breast height（DBH）,tree height,and volume were investigated by establishing sampling plots in Pinus armandii plantations to examine appropriate thinning intensity,time of commence,duration,etc.The results showed that the intensity of thinning had significant influence on the average DBH growth,but it could not promote the height growth.The suitable time of the first thinning would be when the stand was 20 years old,and 30-year-old for the second time of thinning,10 years of interval.The stand reserving density was 2 700 per hectare after the first time of thinning.Additionally,considering the actual situations such as the demand of quick canopy closing and updating,the planting density of P.armandii should be 4500 plants per hectare.