Research On The Community Ecology Of Quercus Wutaishanica In The Huoshan Mountain

Huoshan belongs to loess plateau, Quercus wutaishanicaforest is one of the typical vegetation types in deciduousbroad-leaved forest regions in the warm temperate zone. We chosethe community of Q. wutaishanica as our research object. Plantgeography; quantitative vegetation analysis and Plant populationecology were adopted. The species composition, floristicgeographical element, species physiognomy and structure,Community classification, Inter-specific association, Size structureand Survival analysis, relationships between species diversity indicesand environmental factors of Q. wutaishanica forest, etc, have beendiscussed and concluded mainly as follows:1.Q.wutaishanica populations are growth-oriented populationin this region. Population density, the mean diameter at breast height(DBH) and the maximum DBH have two variation range along thealtitudinal gradient.The survival curve is strictly DeeveyⅡ type. Q.wutaishanica populations has a higher environmental resistance atyoung stage, grew stably at mature stage and declined at old stage.Species biodiversity of Q.wutaishanica was closely related to theirhabitats. 2.Community composition of Ass. Q.wutaishanica forest arerich in plant species, in which there are around247species belongingto162genera of58families. There are significant differencesbetween the number of species and genera that each plant familyincludes. The distribution types of plant genera in the Q.wutaishanicacommunities follow an order North Temperate genera> Cosmopolitangenera> Tropical genera> Endemic to china. This well suggests thatthere are clear temperate characteristics in this area.3.The appearance of community was characterized bydeciduous phanerophytes plants with microphyll or mesophyll, papery,non-entire and single leaf, which has the typical characteristics of thewarm temperate deciduous broadleaf forest.4.Significantly positive correlations exist among the dominantspecies, which suggests that the evergreen broad-leaved forest isstable. This study showed that the proportion of positive and negativeassociation of tree layer and shrub layer was under1, while theproportion of positive and negative association of grass layer wasover1, most of the species pairs did not show significant association,which may be related to the seral stage of the forest and theecological characteristics of the species.5.Based on the results of Inter-specific association，all plantswere classified into six plant function group.6.Q.wutaishanica community were classified into sevenassociations. There were differences of three diversity index amongseven associations and three layer of each association.The index ofspecies diversity of the assoⅢ and Ⅳ were higher，while that of theassoⅠand Ⅵ were lower relatively. The richness and species diversity index of all associations presented the sequence ofherbaceous layer＞shrub layer＞tree layer，and the index of allassociations evenness of the asso Ⅳ was higher，while that of theassoⅢ was lower relatively.7.The species richness and shannon-wiener index showed thelaw of “middle height expansion” as the altitude rising, while theevenness index was rising steadily. Species richness of thecommunities was negatively related to the litter layer thickness andslope gradient. Species richness and diversity index in the slopeexposure indicated that: N> NE> NW> ES> WS> S. Species richnessand diversity index in the slope position indicated that: Lower slope>Middle slope> Upper slope.While the evenness index in slopeexposure and slope position showed no clear regularity. When thecommunity canopy density reached about70percent, Q.wutaishanicacommunity has the highest species diversity.The stepwise regressionequation between environmental factors and species diversityindices was：S=21.813-1.328E-0.993L-1.307C-0.107Sg+0.152Sp-4.557Sa（r=0.87，P<0.01）H=1.742+0.027E-0.058L+0.015C-0.028Sg+0.016Sp-4.5Sa（r=0.73，P<0.01）J=0.571+0.015E-0.011L+0.006C-0.018Sg+0.006Sp-0.003Sa（r=0.506，P<0.01）.Our study can offer some scientific references for protectionand expansion of germplasm resources and sustainable managementof Q. Wutaishanica.