半天然杉阔混交林杉木及其伴生树种种群空间格局

采用聚集强度各指标对福建省虎头山半天然杉阔混交林杉木及其伴生树种的种群空间格局进行分析，综合聚集强度各指标的结果表明：不同立木级杉木及其伴生树种的种群空间分布基本呈聚集分布，随着立木级的增大，各种群扩散趋势越来越明显，其中杉木、米槠和少叶黄杞聚集强度表现为大→小的趋势，拟赤杨和木荷聚集强度表现为大→小→大→小的趋势，虎皮楠和丝栗栲聚集强度表现为小→大→小的趋势，低立木级阶段引起聚集分布的原因主要是环境作用。高立木级阶段引起的树种聚集分布的原因主要是环境作用或自身聚集性。表2参13。

Spatial distribution pattern of Chinese fir and its associated tree species in Mount Hutuo

The spatial distribution pattern of Cunninghamia lanceolata (Chinese fir) and its associated tree species in Mount Hutou were analyzed using different indices of aggregated intensity.The result showed that spatial distribution pattern of different tree class of Chinese fir and its associated tree species were aggregation distribution basically,the more large of tree class,the more apparent the dispersion of different populations.The aggregated intensity of Cunninghamia lanceolata , Castanopsis carlesii and Engelhardtia fenzelii were presented from bigness to smallness, Alniphyllum fortunei and Schima superba presented from bigness,smallness,bigness and to smallness, Daphniphyllum oldhamii and Castanopsis fargesii presented from smallness,bigness and to smallness.The main reason of aggregation distribution in low tree class was environment,the main reason of aggregation distribution in high tree class was environment or aggregation nature of itself.