Study On Quantitative Ecology Of Quercus Wutaishanica Forests In Shanxi

Based on the investigation from the field,Quercus wutaishannica forests in Shanxi were sdudied by using TWINSPAN,DCCA,niche analysis methods,analyzed the relationship between the forests and ecological environment,in order to provide scientific basis for the protection and management of Q.wutaishannica forests in Shanxi.Q.wutaishannica forests were divided into 10 associations by TWIN--SPAN:?.Ass.Quercus wutaishannica-Rosa bella+Rosa xanthina-Carex lan-celoata;?.Ass.Quercus wutaishannica+Pinus tabulaeformis-Rosa xanthina-Carex lanceloata+Artemisia brachyloba;?.Ass.Quercus wutaishannica-Ostr--yopsis davidiana-Carex lancifolia+Deyeuxia arundinacea;?.Ass.Quercus w-utaishanica-Spiraea pubescens+Rosa bella-Carex lancifolia;?.Ass.Quercus wutaishanica-Cotoneaster acutifolius+Spiraea pubescens-Carex lancifolia+Phlomis umbrosa.;?.Ass.Quercus wutaishanica-Corylus heterophylla+Rosa xanthina-Carex lancifolia;?.Ass.Quercus wutaishanica-Viburnum mongolic--um+Cotoneaster multiflorus-Carex lancifolia;?.Ass.Quercus wutaishanica-Cotoneaster multiflorus+Forsythia suspensa-Carex lanceloata;?.Ass.Quercu-s wutaishanica-Cotoneaster multiflorus-Carex duriuscula;X.Ass.Quercus wutaishanica-Lonicera maakii-Carex duriuscula,The results of ordination o-f plots from DCCA were as follows:The first axis(horizontal axis)reflec-ted the variation trend along the latitude of the communities,and the qu--adrat latitude increases from left to right,the increase of latitude reflects the temperature decrease.The second axis(vertical axis)reflected the va-riation along the slope and the slope change of slope along the axis of quadrats from the bottom to top,and the increase of slope positions was along the axis from bottom to top.The results of ordination of the domina-nt species showed that the ordination axes could reflect the changing tre--nd of light,temperature,moisture and elevation of the plants in different layers.Based on the result of the forest classification,the species diversity of the 10 associations and the three layers of the communities were studied by using species richness index(Patrick index),species diversity index(Simpson index and Shannon-Wiener index)and evenness index(Pielou index and Alatalo index),respectively.The results indicated that:(1)The change trend of Patrick richness index was similar to that of Shannon-Wiener diversity index,which was determined by the complexity of the associations and the numbers of species,however,it was opposite to Simpson diversity index.These three indices can reflect the community characteristics more consistently.(2)The Patrick index and Shannon-Wiener index of 10 associations were lower than that of shrub layer and herb layer,it suggested that the different layers of community contribution to community diversity was not equivalent;(3)10 associations diversity index had no significant difference.The niche characteristics of dominant populations including 6 trees,8 shrubs,and 16 herbs of wutaishanica communities were studied by using Shannon-Wiener and Pianka indices.The results showed that:(1)Q.wutaishanica had the widest niche breadth in the tree layer,the value of niche index of it reached 1.653,Rosa xanthina in the shrub layer,the value of niche index of it reached 1.383,and Carex lanceolata in herb layer,the value of niche index of it reached 1.503,suggesting their better adaptability to environmental factors over the other competing species.(2)there was a significant positive correlation between the species niche breadth and the species frequency(P<0.01).(3)Q.wutaishanica is highly overlapped with Betula platyphylla and Pinus tabuliformis in the tree layer,which suggested the similar biological features among them.In the shrub layer,Spiraea pubescens had a higher overlapping with Rosa bella than with the other species,it meant their strong competition for common resource;64.3%of the shrubs was overlapping from 0.1 to 0.3.However,many species pairs in the herb layer had zero overlapping,it suggested that different herbs might vary in their ability to utilize the same resource.