Study On Plant Diversity And Its Influence Factors Of The Evergreen Broad-leaved Forest In Fengyang Mountain

In order to reflect the growth and regeneration of forest trees in this region,and to reveal the mechanism of habitat conditions on the vegetation in this area.This paper takes evergreen and deciduous broad-leaved mixed forest of Fengyang Mountain National Nature Reserve in Zhejiang as the research object,By using the typical sample method,taking a 1hm2 permanent plot for the study.Investigate on parameters for each individual woody plant and have soil experiments.Studies on the species diversity and soil nutrient under different terrain conditions,as well as the relationship between each other.The research result shows that:(1)There are 5,991 individuals belonging to 120 species,61 genera and 35 families in the plot.Including 25 rare species and 44 accidental species.No species appeared to be dominant in the plant community.The species-area curve is S=-110.73e-A/ 0.22+115.97.There are 34 species of species in the temperate zone of the sample,and the regional system consists of the most of the north temperate zone,which accounts for 24.59% of the total number of species.The size distrubition of most species followed a reverse “J” shape,and the number of individuals with small diameter is 69.1%,and the overall improvement is good,and the trend is stable.The spatial distribution pattern shows that the species are presented clumped distribution characteristics,the clump degree from high to low is: Rhododendron ovatum > Cyclobalanopsis glauca > Castanopsis eyrei >Rhododendron latoucheae > Eurya muricate > Schima superba >Lithocarpus glaber> Betula luminifera.(2)As the gradient slackens the tree species richness,diversity and evenness index are getting higher.The diversity index shows middle slope > lower slope > upper slope,richness index shows lower slope > middle slope >upper slope,and evenness index and richness index showed the opposite pattern.The variation of the Simpson diversity index was between 0.8499 to 0.9478,indicating a higher diversity of tree species in the sample area.As the size of the sampling area expanded,the richness of the tree species increased significantly,while the uniformity decreased with the expansion of the sampling area.(3)The soil moisture content,organic matter,carbon nitrogen ratio,hydrolysis nitrogen,effective phosphorus and efficient potassium is A layer > B layer > C layer,and the soil bulk density,pH value and the value of total potassium is characterized by that increases with the soil layer deepen;Most of the nutrients differ significantly between the AB layer,and the difference between the BC layer is reduced.The relationship between soil nutrient content and topography shows that the middle slope is higher than the upper and lower slope,the southeast slope is higher than the southwest slope,and the higher the slope,the lower the soil nutrient content.The nutrient supply in the area was abundant,and the average content of the efficient potassium was 12.9 x 10-2g/kg,which reached a higher level of nutrition.(4)Between the species richness,diversity and evenness index and soil nutrient,there exists a positive correlation with pH,total nitrogen,hydrolysis nitrogen and efficient potassium.Meanwhile,the species evenness also increased as the increasing of soil moisture content.Through the analysis of correlation existing between various nutrient factors,the soil bulk density and pH value between soil physical and chemical properties behave obvious negative correlation,and it is characterized positive correlation between several major nutrients in the soil.