Ecological relations between forest communities and environmental variables in the Lishan Mountain Nature Reserve, China

摘要

This study attempts to reveal the relationships between forest communities and environmental variables in the Lishan Mountain Nature Reserve, North China. The Lishan Reserve is located at E111° 05’ 43” - 111° 56’29”, N35o 29’ 07” - 35° 23’10”, and is a part of Zhongtiao mountain range. Floristic and environmental data from fifty-eight quadrats, each of 10 × 20 m along an elevation gradient from 1400 to 2100 m were analyzed by TWINSPAN, DCCA and species diversity indices. Nine forest communities were distinguished by TWINSPAN, and they are all secondary vegetation. Forest units varied in accordance with altitudinal gradient. The results of DCCA showed that elevation and soil organic matter were the most important factors determining the spatial patterns of forest communities in the Lishan Reserve. Vegetation distribution was also significantly related to slope, aspect, soil N, P, Cu, Zn, pH and conductivity. The interaction between the examined environmental factors was obvious. Almost all environmental variables were significantly correlated with elevation and soil organic matter. The effects of soil Cu on forests was important in the studied area because Cu affects the effects of most other variables. Species richness increased linearly with the elevation, which is in contrast to the hump-shaped pattern of diversity-elevation relations. However, species heterogeneity and evenness followed the hump-shaped pattern with elevation. Besides elevation, slope was also a significant factor to species diversity in forest communities. Species diversity was negatively correlated with most soil variables except Cu. The interactions between species diversity and soil variables need more attention in future studies.