The Study Of Structure Characteristics Of Oak Community In Huang Baiyuan Nature Reserve

There are about300species of oak, which distributed in Asia, Africa, Europe and theAmericas.There are about60species in China, including the evergreen, in Qinling and thesouth of Qinling, mainly for broad-leaved forest tree species and afforestation tree specie,which are the important species of restoring oak woods, creating mixed pine oak, pine pureforest transformation, ecological environment improvement and energy forest construction.The major oak species in Huang Baiyuan Nature Reserve are Quercus variabilis, Quercusacutidentata, Quercus aliena and so on.Using the sample survey method, researched the physical characteristics, speciescomposition, dominant species, life forms, biodiversity, tree height and diameter distributioncharacteristics and community associations and other aspects of succession models of the oakcommunity in Huang Baiyuan Nature Reserve.Forest of Quercus acutidentata mainly distributed in the higher elevations of the hillsideor beam roof, leading to less anthropogenic influence, well-developed, the largest area,complex community structure and species composition. Quercus oak forest and Quercusaliena forest are greatly influenced by human, smaller area, mainly distribute in low-lyingposition, simple forest structure. The study found that Oak Community Appearance showedobvious seasonal changes by different colors during the year for easy identification.Quercus variabilis communities include23kinds of woody plants,9kinds of herbs,4kinds of lianas; Quercus acutidentata communities include51kinds of woody plants,14kinds of herbs,25kinds of lianas; Quercus acutidentata communities include29kinds ofwoody plants,6kinds of herbaceous. There is a largest number of species of woody plantscommunities in Quercus acutidentata communities, middle number of woody plants inQuercus acutidentata communities, the least number of woody plants in Quercusvariabilis communities. Thus, tree layer rich in plant composition, complex structure andbetter community stability of Quercus acutidentata communities; As for the Quercusvariabilis and Quercus aliena communities tree layer plant species composition is relativelysimple, relatively simple structure, less community stability.Oak community space in layers and can obvious distinguish the tree layer, shrub layerand herb layer in vertical direction. There are certain interlayer plant in Quercus variabilis communities and Quercus acutidentata communities. There are fewer species of tree layer,relatively neat canopy, fewer plant species within the community of Quercus variabilis andQuercus aliena, which the shrub layer as well as the herb layer coverage is low, however,the community structure of Quercus variabilis is relatively complex and the tree layerconstituted by a variety of species stratified structure with a larger plant cover whencomparing to the Quercus variabilis and Quercus aliena communities.Whether in any kind of oak community, there are most phanerophytes, as62.5%inQuercus variabilis forest,56.7%in Quercus acutidentata forest,79.3%in Quercus alienaforest; hemicryptophyte take the second place, as9.4%in Quercus variabilis forest,8.9%inQuercus acutidentata forest,6.9%in Quercus aliena forest; least cryptophyte, as12.5%inQuercus variabilis forest,14.4%in Quercus acutidentata forest,13.8%in Quercus alienaforest.It shows that oak communities in Huang Baiyuan Nature Reserve growing in a cooland moist climate, the altitude suitable for Quercus variabilis, Quercus acutidentata, Quercusaliena.There are abundant plant species, complicated plant species composition and communitystructure in Oak community. There are the most abundant plant species in Quercusacutidentata communities and the community structure and plant composition are morecomplicated. Followed by Quercus aliena communities, the structure of Quercus variabiliscommunities is relatively abundant, diversity index and richness index of the tree layerspecies are relatively high, however, evenness index is low, Quercus variabilis dominant,accompanying a variety of other species without absolute advantage dominant species,Quercus variabilis, Quercus acutidentata, Quercus aliena and other species build acommunity together.The height and diameter at breast height diameter of Oak community, showing thecharacteristics of generation of initiation and uneven forest. Tree height and diameter atbreast height diameter class change of Quercus variabilis communities and Quercus alienacommunities is not very significant, indicating that community regeneration advantage isnot very significant; the Quercus acutidentata species distribution as tree height to6~8m,8~12m,16~20m of the majority; mostly individuals with average diameter16cm, diameterto12~18cm,, indicating that advantage of community regeneration is obvious.The study found that Oak community in Huang Baiyuan Nature Reserve can bedivided into four groups, which the Quercus variabilis forest can be divided into Quercus-leafy lespedeza-Carex lanceolata Ass Quercus variabilis-Lespedeza buergeri-Carexlanceolata as a group; Quercus acutidentata forest can be divided into Quercus acutidentata-wood and bamboo Bashan-Carex lanceolata associations Ass Quercus aliena var acuteserrata-Bashania fargesii-Carex lanceolata and Quercus acutidentata-Lespedeza-Wintergreen ass Ass Quercus aliena var acuteserrata.-Lespedea formosa-Pyrola rotundifoliassp.chinensis as two groups. Quercus aliena forest can be divided into Quercus aliena-NorthSpiraea-White Spike Carex associations Ass Quercus aliena-Spiraea fritschiana-Carexpolyschoenoides as a group.The relationship between Plant survival and growth with theenvironment, with the change of with altitude, slope, soil fertility, water and heat conditions,vegetation types show different distribution. Plant variety, rich in plant resources in HuangBaiyuan Nature Reserve has important ecological value and research value.Oak community in Huang Baiyuan Nature Reserve presented in the naturalrecovery-based, supplemented by human interference pattern secondary succession forestcommunities. In the community succession species, Branch community, genera and speciesshowed a significant increase compared with the degree of community species diversity andcommunity structure of the complex has been some improvement. With the development ofcommunity succession process, plant species, feature richness are increasing and improving.Treats Huang Baiyuan Nature Reserve is important in regulating the regional climate,maintaining ecological balance, promoting sustainable ecological and economic development,research the Rock Process of Oak community in Huang Baiyuan Nature Reserve hasimportant ecological meaning.