Species Diversity And Dominant Population Dynamics In The 5ha Plot In Gutianshan From 2007 To 2012

Forests provide a variety of resources and services for human survival and development,which is one of the most biologically diverse ecosystems on earth.In recent years,forest biodiversity and its maintenance mechanism have become the key problem of ecology research,and species diversity and dominant species play an important role in the stability and succession of forests.The researches of species diversity and dominant population dynamics of evergreen broad-leaved forest can provide scientific basis for the reconstruction,restoration and protection of evergreen broad-leaved forest.Accordingly,this research takes two reexamination results for 2007-2012 years of 5ha evergreen broad-leaved forest in Gutianshan,Zhejiang province,as the basis,through the analysis of community species composition,importance value,diversity index and dynamic change of dominant population in different growth types,etc.,studies the dynamics of community structure and the dynamic characteristics of major population.This study contributes to understanding the community characteristics and dominant population regeneration of 5ha fixed plot in Gutianshan.It provides theoretical and data support for the study of the individual ecology and community succession of 5ha in the Gutianshan.The main results are as follows:1.Species richness:Among 2007-2012 years,Gutianshan 5ha plots of woody plants(DBH>lcm)rich from 148 species(48 families,98 genera)to 158 species(53 families,107 genera),4 species disappeared,14 new species were added,including 3 kinds of trees and small trees increased respectively,and 4 kinds of shrubs increased,the number of individuals increased from 18446 strains to 19520 strains,a net increase of 1074 strains.In terms of the composition of the family,compared with 2007 in 2012,the dominant families increased by 1,and the dominant genera did not change.2.Dominant species:the dominant species of the top 4 of the important value of different growth type in 2007 and 2012 did not change.Among the top 30 species,the tree species were the largest,with the smallest shrub species;compared with 2007,Quercus serrata and Adinandra mellettii disappeared in the top 30 species of the important value in 2012,while Machilus grijsii and Myrica rubra entered the top 30.the important values of other species have changed to varying degrees,but the overall changes have been minor.3.Species diversity index:Among 2007-2012 years,the Shannon-Wiener index,Pielou index and Simpson index had little difference.The Shannon-Wiener index changed from 3.674 to 3.752,the Pielou index changed from 0.735 to 0.741,and the Simpson index changed from 0.044 to 0.046.The variation of the above diversity index did not change obviously in the past 5 years.4.Different growth types of dominant species:from the dynamic point of view,the other 10 species were all reduced,except for the increase of Daphniphyllum oldhamii and Chimonanthus salicifolius.From the view of average DBH,the average DBH of Castanopsis eyrei,Daphniphyllum oldhami,Chimonanthus salicifolius and Corylopsis glandulifera decreased,the average DBH of the remaining species increased.From the point of size class structure,Castanopsis eyrei,Daphniphyllum oldhami,Eurya muricata,Chimonanthus salicifolius and Itea omeiensis belong to expanding population;Daphniphyllum oldhamii and Camellia fraterna belong to stable population;Schima superba,Pinus massoniana,Rhododendron ovatum,Loropetalum chinense,Rhododendron latoucheae,Corylopsis glandulifera belong to declining population.The spatial distribution pattern of the death individual and the spatial distribution pattern of the recruitment individual are developed from the aggregation distribution to the random distribution as the sampling scale increases..