四川山矾种群在不同群落中空间分布格局研究

选取了方差均值比(ID)、聚集度大小指数(ICS)、G reen指数(G I)、聚集频度指数(ICF)、平均拥挤度指数(IMC)、聚块度指数(IP)、莫里西塔指数(IM)等7项指数,分析研究了缙云山4个不同群落中四川山矾幼苗、幼树、小树、大树的空间分布格局。结果表明:(1)四川山矾在常绿阔叶林中多呈聚集分布,在针阔混交林中则多呈随机分布;(2)四川山矾在不同类型的群落中表现出不同的分布格局,在同一群落中不同年龄阶段(不同层次)的分布格局也不相同;(3)四川山矾、大头茶等常绿阔叶树种有取代马尾松、杉木等针叶树种,并使针阔混交林向常绿阔叶林演替的趋势。

STUDY ON THE SPATIAL DISTRIBUTION PATTERNS OF SYMPLOCOS SETCHUANENSIS POPULATION IN DIFFERENT COMMUNITIES IN THE JINYUN MOUNTAINS

Index of dispersion(ID),index of cluster size(ICS),Green index(GI),index of cluster frequency(ICF),index of mean crowding(IMC),index of patchiness(IP) and Moristia's index(IM) were used to analyze the spatial distribution patterns of 4 different communities of Symplocos setchuanensis(seedlings,sapling trees,small trees and big trees) in the Jinyun Mountains.The species(S.setchuanensis) was found to assume a clump distribution pattern in evergreen broadleaved forests and a random distribution pattern in mixed coniferous and broadleaf stands.Different community types displayed different distribution patterns,and distribution patterns varied with the age of the trees.A tendency was observed for the evolution of mixed coniferous and broadleaf stands to evergreen broadleaved forests of substitution of evergreen broadleaved tree species(S.setchuanensis and Gordonia acuminata) for conifers(Pinus massoniana and Cunninghamia lanceolata).