天山云杉林林分特征与立地条件关联分析

Association Analysis Between Forest Stand Traits and Habitat Conditions in Picea schrenkiana var. tianschanica Forest in Tianshan Mountains

为探讨立地类型对林分特征的影响机制,以新疆西部天山云杉林中系统布设的监测样方数据为基础,研究了天山云杉林分结构特征与立地因子之间的关系.在192个20 m×20 m调查样方中共调查到1 909个DBH≥1 cm植株,胸高断面积共计291.632 m2;天山云杉株数和胸高断面积最大,分别占林分总株数和总断面积的91.5%和97.4%.扩散系数C、平均拥挤度m*、聚块性指数m*/m和负二项分布参数K分析显示,天山云杉、天山桦、天山花楸、天山茶藨子和刚毛忍冬均呈聚集性分布.天山云杉喜坡度较大的立地环境,而坡度较缓的阴坡及半阴坡不适合天山云杉的生长和发育;天山桦喜坡度较缓的阴坡及半阴坡立地环境;天山茶藨子喜坡度较缓的阳坡及半阳坡立地环境.天山林区放牧干扰在一定程度上影响树种分布格局和立地偏好分析结果.

between community structure and habitat were analyzed to study the effects of habitat type on the community structure on the basis of the investigated data of system layout monitoring sample in the Picea schrenkiana var. tianschanica forest in west Tianshan, Xinjiang, China. Amongst 192 （20 m x 20 m） plots, 1909 individual plants with DBH 〉 1 cm were investigated, and the sum of basal area at breast height was up to 291.632 m2. The stem and basal area at breast height of P. schrenkiana var. tianschanica were 91.5% and 97.4% respectively, the highest among all species investigated. According to diffusion coefficient C, mean crowding m＇, aggregation index m＊/m, negative binomial distribution parameters K, all five species （P. schrenkiana var. tianschanica, Betula tianschanica, Sorbus tianschanica, Ribes meyeri and Lonicera hispida） showed significant aggregation. P. schrenkiana var. tianschanica preferred habitat with steep hill, but not shady slopes and semi-shady slopes on section of gentle slope. Betula tianschanica preferred habitat with shady slopes and semi-shady slopes on section of gentle slope, while Ribes meyeri preferred habitat with sunny slopes and semi-sunny slopes on section of gentle slope. Grazing disturbance influenced the distribution pattern and habitat preference of the tree species in Tianshan forest zone to some extent. Fig 2, Tab 5, Ref 24