Study on the spatial pattern of major populations in the needle and broad-leaved mixed evergreen forest in Niumulin Nature Reserve Zone of Fujian Province

Based on variance-mean ratio，x²-test，cluster-intensity coefficient，quadrat variance method，etc．，the spatial pattern of major tree populations from Pinus massonina+Castanopsis larnontii community(needle and broad-leaved mixed evergreen forest)in Niunm lin Nature Reserve Zone of Fujian Province was studied，showing that the populations of Pinus massonina ，Castanopsis lamontii，Cinnamomum austros and Schima superba distribute randomly；the populations of Castanopsis carlesii，Lithocarpus oleaeJblius and Machilus veltina have a pattern of clump distribution respectively．The analysis of pattern intensity indicates that the intensity of three clumped distribution population is lower．The comparison shows that the order of their intensities is Castanopsis carlesii population> Lithocarpus oleaefolius population> Machilus veltina population．In the research，there is a prediction that the populations of clumped distribution should be constructive populations of the community in the future．