林分因子对神木垒不同森林群落林下植物多样性的影响

Effects of Stand Factors on Understory Plant Species Diversity in Different Forest Communities in Shenmulei Forest Area

为探究神木垒不同森林群落林下植物多样性的差异,采用典型样地法,以夹金山神木垒的5种主要森林群落:云杉林、丽江云杉林、红杉林、针阔混交林、阔叶林为研究对象,对不同森林群落林下植物物种组成和物种多样性进行比较,并对林分因子和林下植物多样性进行冗余分析,确定影响林下植物多样性的主要林分因子,为当地森林经营管理提供理论依据。结果表明,(1)在研究区内共记录林下植物147种,隶属于61科,108属,云杉林群落林下植物的科属种组成最丰富;(2)各类型群落的H值、H′值、D值、J_(SW)值均为:草本层>灌木层,灌木层多样性最高的群落为云杉林群落,草本层多样性最高的群落为丽江云杉林群落,针阔混交林群落、阔叶林群落林下植物多样性较差;(3)平均枝下高与林分密度是影响灌木层物种多样性的主要林分因子(P<0.01),平均枝下高与灌木层的D值、H值、H′值呈负相关关系,林分密度与灌木层4个多样性指数均呈正相关关系;同时平均枝下高也是影响草本层物种多样性的主要林分因子(P<0.01),平均枝下高与草本层H值、H′值、J_(SW)值呈正相关关系。本研究认为,云杉林群落与丽江云杉林群落的林下植物多样性较高,平均枝下高与林分密度是影响神木垒不同森林群落林下植物多样性的主要林分因子。

In order to explore the differences of understory plant diversity in different forest communities in Shenmulei,we used the typical sample plot method to study the five major forest communities in Shenmulei Forest Area of Jiajin Mountain:Picea asperata forest,Picea likiangensis forest,Larix potaninii forest,coniferous and broad-leaved mixed forest and broad-leaved forest.The species composition and species diversity of understory plants in different forest communities were compared,and the redundancy analysis of stand factors and understory plant diversity was carried out to determine the main stand factors affecting understory plant diversity,which could provide theoretical basis for local forest management.The results showed that,(1)147 species of understory plants belonging to 61 families and 108 genera,were recorded in the study;the families,genera and species composition of understory plants in P.asperata forest community was the richest.(2)The H,H′,D and J SW values of all types of communities were:herb layer>shrub layer.P.asperata forest community had the highest species diversity in shrub layer,P.likiangensis forest community had the highest species diversity in herb layer,and the diversity of understory plant species in coniferous and broad-leaved mixed forest community and broad-leaved forest community was poor.(3)The average under branch height and stand density were the main stand factors affecting the species diversity of shrub layer(P<0.01).The average under branch height was negatively correlated with the D value,H value and H′value of shrub layer,and the stand density was positively correlated with the four diversity indexes of shrub layer.The average under branch height was the main stand factor affecting the species diversity of herb layer(P<0.01).The average under branch height was positively correlated with the H value,H′value and J_(SW)value of herb layer.This study suggests that the species diversity of understory plants in P.asperata forest community and P.likiangensis forest community is high.The average under branch height and stand density are the main stand factors affecting the diversity of understory plants in different forest communities in Shenmulei.