Analysis Of Plants Diversity, Of Major Vegetation Types, In Donglign Shan, Beijing

Understanding the distribution of species and communities of species at a given scale, identify environmental conditions that constrain this distribution and modelling species distribution areas or communities of species are at the heart of scientific issues for the implementation of programs preservation of biodiversity, the orientation of the territory planning policies but also to assess the impact of current global change. Plants abundance used were collected at the Dongling Shan located between 40°00’-40°03’North and 115° 26’-115°30’East, has 110km southwest of Beijing. In the present study, we aim to test the hypothesis according to which the plant species abundance distribution in conserved forests corresponds to a log normal distribution, indicating that species are regularly distributed in the ecosystem. The observed abundance distribution of the plant species was therefore compared to a log normal, a log series and a broken stick distribution model. An estimate of the species richness, showed variation of this richness according to the altitude. Species richness decreases from 1472.1 m to 1366 m and increase from 1312.5 m to decrease at 1189.5 m. The community, as a whole, is well diversified (Shannon= 2.27), Simpson index (D= 0.86). By calculating the alpha diversity for each altitude, low diversity was observed in 1366 m (H= 0.43) and 1189.5 m (H= 0.75). Sorensen’s index was calculated (beta diversity). The results showed a high similarity between the altitudes 1466.8 m and 1472.1 m (B= 0.82) and a very low similarity between elevations 1366 m and 1466.8 m(β= 0.17), and also between 1189.5 m and 1472.1 m(B= 0.31). The observed distribution throughout the community was found similar to the log normal distribution. The observed species abundance distribution at 1366m was found similar to the log series model, which suggests the impact of disturbance on the abundance distribution. However, the observed plant model distribution, at 1189.5m,1312.5m, 1466.8m and 1472.1m. was found similar to the lognormal model, which suggests the absence of disturbance in these altitudes. The results obtained show signs of disturbance at 1366 m (H= 0.43 and a distribution model conforming to log series model). Given the important role of plants for the city of Beijing, a particular attention must be paid on this situation through other studies to identify the factor that is and will be the origin of this disturbance, in order to enhance the conservation of this ecosystem.