北京低山侧柏人工林资源分布与生长状况分析

对北京低山侧柏人工林资源分布及生长状况进行了分析。结果表明:7个山区县侧柏人工林面积为7.84万hm2,幼龄林面积占92.01%,中龄林面积占6.5%;幼龄林蓄积占低山侧柏人工林总蓄积的72.7%,中龄林蓄积占20.9%,近成熟林及过熟林蓄积占的比例较少。不同立地条件下,坡向、坡度对于侧柏的生长影响较大,分布于阳坡的侧柏生长较快。不同立地等级下材积连年生长量和平均生长量在54a时仍未相交。利用Forstat2.0和SPSS 18.0分析软件,模拟不同立地等级侧柏胸径、树高、材积的生长过程,并建立各因子生长模型。结果表明,Richards生长方程能较好地预估北京侧柏人工林的生长。

The Resource Distribution and Growth Status for Platycladus orientalis Plantations in Lower Mountains of Beijing

The analysis was done on the resource distribution and growth status for Platycladus orientalis plantationthe in lower mountain of Beijing,The results show that the area of Platycladus orientalis plantation in 7 mountainous counties of Beijing is 78400 hm2 with 92.01% as young stand and 6.5%middle-age forest.young stand accounted for 72.7% of the total cumulation,20.9% middle-age forest,near mature stand and over-mature stand had less proportion of the total.In different site conditions,aspect and slope had greater impact on the growth of P.orientalis and those located in sunny slope were growing faster.The current annual volume increment and the mean volume increment were not intersected at 54 years old in different site grade.Using Forstat2.0 and SPSS18.0 analysis software,Platycladus orientalis diameter,height and volume of growth process in different site conditions were simulated,and the growth factor model established.Richards growth equation can be used to predict the growth of Platycladus orientalis plantation accurately.