Dynamics And Structure Of The Deciduous Broad-leaved Forest Forest Community In Baotianman National Nature Reserve

The reaserch is based on the two surveys data of Baotianman deciduous broadleafed forest in 2009 and 2014.The study of community dynamic characteristics during 5 years is built on species composition,biodiversity index,quantitative characteristics,diameter classes and spatial distribution.The individuals number which DBH ≥ 1 cm decreased from 83 to 81.Two species have been added.4 species disappeared because of the few individuals of them had been dead.The individual number decreased from 2547 to 2166.The death individual number is 571.The death number of individuals accounted for 22.4% of total number of individuals in 2009,the number of new individual is 191.Net decrease individual number is 381.Dead individuals is greater than the added.The number of dead and added of the tree species was more than it of shrub species.There were 38 species which their mean DBH decreased as well as 45 species increased.Individual death present that the middle diameter size individual death were more the size class structure of small diameter and large size class.The α index shows that the diversity of the sample area decreases during five years.It may due to that the death rate much greater than the recruitment.The study of phylogenetic community structure indicates that the environment filter clogging effect plays a key role in the process of the construction of the community.Pearson correlations between the soil f index and diversity index indicate that rapid available phosphorus and total nitrogen have pronounced influence on biodiversity and the distribution of biodiversity.The study of point of distribution pattern illustrate that the distribution aggregation degree reduced.In all,environmental heterogeneity has certain influence on species diversity and distribution pattern formation in deciduous broadleaved forest forest community in Baotianman National Nature Reserve.