Studies On Plant Community Structure Of Miaodao

From May, 2005 to October, 2007, Author has carried on investigationing and collecting, and vegetation investigation all-round and systematically many times to Miaodao, altogether gathers 216 portions of specimen. After to the specimen appraisal and quarters data analysis, the vascular plant community structure are analyzed on emphasis, the main result as follows:1.12 typical forest communities have 106 species altogether; the main species includes: Pinus thunbergii, Robina pseudoacacia,Quercus acutissima, Ziziphus jujuba var . spinosa, Vitex negundo var . heterophylla, Grewia biloba var . parviflora ,Lespedeza, Carex lanceolata Cleistogenes chinensis, Zoysia japonica, Dendranthema indicum, Artemisia gmelinii. The vertical structure of community may divide into the tree layers, the bush layer and the herb layer 3 layers. In 12 quarters, the diversity of quarter 6 (Pinus thunbergii forest), quarter 4 (Quercus acutissima forest) , quarter 2 (Pinus thunbergii - Robina pseudoacacia,- Quercus forest) and quarter 3 (Pinus thunbergii forest) is higher, the diversity of quarter 12 (Robina pseudoacacia forest), quarter 10 (Pinus thunbergii forest) and quarter 5 (Robina pseudoacacia forest) is lower, this has close relationship with the community structure and the habitat .2.The analysis on 12 typical forest communities flora indicates that the dominant ingredient are temperate-type, and it has something with tropical flara. The analysis on leaf forms of quarter indicates that, the dominant type is microphyll, mesophyll and compound leaf also holds an greater proportion. The analysis on life forms of quarters indicates that the dominant type is phanerophytes and hemicryptophytes, the crypthophytes also accounts for the certain proportion, this adapts with the local climate characteristic.3. The species richness index R and Shannon-Wiener index H of each layer on quarter community is: herb layer> bush layer> tree layer; evenness index J1 is:bush layer > herb layer > tree layer,this shows that the distribution of bush layer is most even; the ecological dominance indexλis: tree layer > bush layer > herb layer, it is just right opposite with H value and R value, the H value and R value of herb layer is biggest,this shows that herb layer's contribution to community diversity is maximal. After notable t-test, the difference of the ecological dominance indexλand evenness index J1 among tree layer, bush layer, the herb layer is not notable, but the difference of species richness index is extremely notable; the difference of Shannon index H is extremely notable between tree layer and bush layer, between tree layer and herb layer, the difference of Shannon-Wiener index between bush layer and herb layer is not notable, this result has explained that community is in the front term stage or medium term stage of community succession.4.Divides 12 typical forest communities into the Pinus thunbergii forest , the Robina pseudoacacia forest, the Quercus acutissima forest, the Pinus thunbergii - Robina pseudoacacia- Quercus forest 4 types of forest types, the species diversity results is : the species richnes index R : Pinus thunbergii forest > Pinus thunbergii - Robina pseudoacacia-Quercus forest>Quercus acutissima forest> Robina pseudoacacia forest, the Shannon-Wiener index H is : Pinus thunbergii - Robina pseudoacacia- Quercus forest> Quercus acutissima forest>Pinus thunbergii forest > Robina pseudoacacia forest, the evenness index J1 is : Pinus thunbergii - Robina pseudoacacia- Quercus forest> Quercus acutissima forest>Pinus thunbergii forest > Robina pseudoacacia forest, its trend is consistent with H. The difference of the species diversity index among different community to advance along with succession and development of the community, but the species diversity of the most stable community is not highest. The ecological dominance indexλis: Robina pseudoacacia forest > Pinus thunbergii forest > Quercus acutissima forest > Pinus thunbergii - Robina pseudoacacia- Quercus forest, its size is just right shoulder a relevance with H, J1, R, this has explained that the community advantage species is obvious, the species diversity index is small increasingly; the probability among species meeting PIE is: Pinus thunbergii - Robina pseudoacacia- Quercus forest> Quercus acutissima forest>Pinus thunbergii forest > Robina pseudoacacia forest, it is just right opposite withλ. In the end, the succession order of plant community in Miaodao has been discussed.5.The main vegetation type of Miaodao including the coniferous forest,the deciduous broad-leaved forest, the needle-leaved and broad-leaved mixed forest ,the shrub, the shrub and grass, the halophytic vegetation, the psammophytic vegetation. Key word: Miaodao; Plant Community structure; Species diversity;Vegetation...