Slope aspect and slope position have effects on plant diversity and spatial distribution in the hilly region of Mount Taihang, North China.

In order to investigate the species diversity and spatial distribution of vegetation as affected by slope aspect and slope position in the hilly region of Mount Taihang, North China, eco-characteristics and abundance distribution of shrubs and herbs were studied at different geographical locations in 2008. Samples were collected along 32 transects at different slope positions (upper, medium and lower) of southern and northern slopes. Results show that vegetation mainly consists of communities with a limited number of species, and a total of 44 species (9 shrubs and 35 herbs) were recorded. Shrubs are widely distributed in southern slopes while herbs are better distributed in northern slopes. Southern slopes exhibit higher shrub species diversity while northern slopes have higher herb species diversity. In addition, lower positions host highest species diversity and richness, while hotter and drier mid-slopes support lowest species diversity and evenness. Due to the semi-arid climate and limited resources, only few species can adapt well to the thirsty local environmental conditions, and they have rather wider niches and occupy most available resources. The community structures are rather similar among the slope configurations, and all comprised of few common but most occasional species, with the former greatly exceeding the latter in the total number of individuals. The results indicate that slope aspect and slope position have strong influence on plant diversity and spatial distribution, but little effect on plant assemblage. Soil available water capacity and solar radiation are the major factors influencing the plant diversity and distribution in the study area.