| Abstract |
The Baishuihe National Nature Reserve is located in the southeastern Longmen Mountains in Pengzhou, Sichuan,China. Eevergreen broad-leaved forests, deciduous broad-leaved forests, coniferous forests, subalpine and alpine shrubs, alpine meadows, and screes cover the southeastern slopes from foot to top of the mountains. From 1 400 to 3 900 m in the Nature Reserve, 52 plots were investigated with an interval of 100 m in altitude. Diversity of communities and their changes along altitude gradient were studied. The results showed that the richness and diversity of tree layer species decreased linearly with the increasing of altitude, while those of shrub layer and herb layer species decreased parabolically. Trees decreased from 12 at 1 400 m to only 2 species at timberline. Shrubs and herbs decreased from 35 and 38 at 2 000 m to 5 and 20 species at 3 800 m, respectively. Tree species are replaced obviously by others with the increase of altitude This shows that altitude contains many environmental factors, which affect the distribution, structure and species diversity of plant communities in the area.Fig4,Tab 1. Ref 20 |
