Study On Quantitative Ecology Of Ostryopsis Davidiana Communities In Shanxi

Ostryopsis davidiana belongs to the Betulaceae,Ostryopsis. Ithas a strong life force, channeling the root of performance,drought,cold and poor resistance,is endemic to China, good retaining shrubs,improve the soil and soil and water conservation role. It is a higheconomic value,use a wide range of shrub species. In this paper, onthe basis of field investigation, the number of applicationsecological methods, from the perspective of community ecology,the Ostryopsis davidiana community a more systematic andcomprehensive study, including community species composition,physical characteristics, classification and sorting, speciesdiversity, ecological species groups and niche, quantitativeanalysis of the ecological relationships of Ostryopsis davidianacommunities and the environment, in order for Ostryopsis davidianapopulation and community restoration, protection and rational useof resources to provide the scientific and theoretical basis.(1) 86 Ostryopsis davidiana quadrat were recorded in seed 139kinds of plants ,belonging to 106 genera and 40 families.Gymnosperms is 2 families, 2 genera and 3 species , angiosperms is38 families,104 genera and 136 species. Section 4 familiescontaining more than 5 genera, single, widowed species of 53 genera ,these families, genera play an important role in the floristiccomposition. Branch distribution types, world distribution of the 23families, north temperate, 10 families, respectively, accounted for57.50% and 25.00% of the families. Areal type, dominant temperatedistribution (72 genera total is 80.90%), which have obviousadvantages of the northern temperate zone (36 genera the total is33.96%), reflecting the flora in the area department of warmtemperate zone. The community the appearance Hemicryptophytesphanerophytes shows the cold winters and long warm-temperatedeciduous broad-leaved forest region.(2) The application of TWINSPAN classification method dividedthe 86 samples of the community for eight stands, the classificationresults reflect the relationship between plant community types andenvironmental gradients. DCA, the results show that: the first axisof DCA ordination diagram of plots basically reflects the elevationforest communities where the environment and litter layerthickness, that is, from left to right, the elevation graduallyincreased, the litter layer thickness gradually, but did not changesignificantly. Two axis (vertical axis) reflects the slope and slopeposition of the various forest communities where environmentalsamples, from bottom to top, the slope gradually from slow to steep.(3) The species richness index, diversity index and evennessindex of species diversity, the results showed that: there aredifferences between the plant associations between speciesrichness index and diversity index and evenness index, While theplant associations III and ofⅧthe richness index and diversityindex and evenness index higher, the plant associations I andⅥ richness index, diversity index and evenness index is relatively low.Abundance index of the herbaceous layer on the plant associations,diversity index and evenness index of the contribution.(4) Usingχ~2 test, Spearman rank correlation analysis combinedwith the adaptability of plant populations in ecological speciesgroups the Ostryopsis davidiana communities, the results showedthat: the herb has a high level of related species, shrubs level. Thepositive association between the communities in between thelayers and communities ratio is greater than the negativecorrelation, significant rate greater than the negative forwardrate ,is in the fluctuations during description Ostryopsis davidianacommunity. Based on the result Of interspecific association and thecharacteristics of Plants ecological adaptation, the 40 dominantswere divided in to three ecological species groups: Pinus bungeanaecological species group,Ostryopsis davidiana ecological speciesgroup, Myripnois dioica ecological species group.(5) Using Levins niche breadth index, the Hurlbert niche widthindex and Pianka’s niche overlap index of Shanxi Ostryopsisdavidiana community 40 niche were determined, the results showedthat:：Pinus bungeana and Platycladus orientalis arborvitae treelayer in the larger niche breadth，LNB and HNB 0.8857,0.0748 and0.8708 , 0.0686, respectively; Shrub layer Ostryopsis davidiana、Rosa xanthina and Cotinus coggygris var. prbescens sumac largerniche breadth, the LNB and HNB is for 1.9143,1.7046,1.3825 and0.9964,0.5570,0.2547; Shrub layer of niche overlap in the largest isCarex lanceloata and Artemisia sacrorum, the LNB and HNB were1.8367,0.7430 and 1.7615,0.5680. Niche breadth, the greater the ability to adapt to the environment, the ability to use variousresources, and often in a dominant position in the community. Nichein the shrub layer, overlapping the largest tiger Ostryopsisdavidiana and Rosa xanthina of the overlap is worth to 0.711,indicating that the quadrats in the survey are very similar, both useof resources and the environment; Carex lanceloata and Artemisiasacrorum niche overlap in the herb layer, reaching 0.694, indicatingthe mode of the two habitats most similar in its records of thespecies.