克隆乔木黄牛奶树空间点格局分析

常绿小乔木黄牛奶树具有有性繁殖和克隆繁殖两种繁殖方式，对森林更新意义重大.以种群个体空间分布的坐标点图为基础，采用点格局分析法对其不同生境下克隆苗与实生苗的分布格局及其相互关系进行了研究.结果表明，克隆苗和实生苗的密度顺序都是常绿阔叶林竹林针阔混交林，在水肥资源丰富、郁闭度较大(常绿阔叶林和竹林)的生境中，两类苗密度都较大，但克隆苗占优势；在水肥资源贫乏光照较强的生境中，两类苗数量均较低，实生苗占优势.黄牛奶树克隆苗与实生苗在竹林与针阔混交林下以集群分布为特征，常绿阔叶林在小尺度下呈集群分布但随尺度的增大呈现为随机分布；克隆苗与实生苗的关系在密度较小的竹林和针阔混交林为显著正相关，而对于密度较大的常绿阔叶林，小尺度下为正相关，大尺度下则呈负相关. 

Spatial pattern analysis of the clonal tree Symplocos laurina

There are two methods for Symplocos laurina propagation: clonal reproduction and sexual reproduction,which play significant roles in forest regeneration.Point pattern analysis,based on spatial mapped points of individuals' distribution,was employed to obtain spatial pattern of ramets and sexual seedlings of S. laurina in different habitats,as well as the relationship between them.The results showed that densities of ramets and sexual seedlings in different habitats had the same order,ie evergreen broadleaved forests>bamboo forests> needle broadleaved forests.In habitats with abundant water and fertility and lower light,such as in an evergreen broadleaved forests or a bamboo forests;clonal ramets took advantage in terms of number and clonal propagation was dominant. In habitats with a lack of sufficient nutrition and with stronger sunshine,the densities of both ramets and sexual seedlings were high;and sexual seedlings had much more individuals than ramets.The seedlings of S.laurina clumped in bamboo forests and needle broadleaved forests.The distribution pattern varied with the increase of scale from clumping distribution to random distribution in an evergreen broadleaved forests.The relationship between ramets and sexual seedlings were almost significantly positively correlated with each other in bamboo forests and needle broadleaved forests.The relationship also changed with the increase of scale in an evergreen broadleaved forests,with positive association on the smaller scale,and negative association on a larger scale.This indicates that scale is an important factor in controlling the spatial distribution pattern of S.laurina seedlings.