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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 distribution and growth of Platycladus orientalis plantations in Beijing were analyzed. The results showed that the arborvitae plantation area of 7 mountainous districts and counties was 78400 hm2, the young forest area accounted for 92.01% and the middle-aged forest area accounted for 6.5%; the young forest accounted for 72.7% of the total volume of P. orientalis plantation, The middle-aged forest accounts for 20.9% of the total, while the mature and over-mature forests account for less. Under different site conditions, the slope and slope had a greater impact on the growth of oriental arborvitae, and the oriental arborvitae distributed on the sunny slope grew rapidly. The volume of annual growth and the average growth of the volume under different site levels still did not intersect at 54a. Forstat2.0 and SPSS 18.0 software were used to simulate the growing process of DBH, tree height and volume at different site levels, and to establish the growth model of each factor. The results show that the Richards growth equation can better predict the growth of Platycladus orientalis plantations.