Subalpine tall-herb vegetation patterns: a case study from the Khamar-Daban Range (southern Baikal region, Eastern Siberia)

In this study, we present the first investigation of diversity and ecology of tall-herb vegetation (class Mulgedio-Aconitetea Hada & Klika in Klika & Hada 1944) on the Khamar-Daban Range, the generally assumed easternmost distribution limit of this class. We collected data of 162 relevs in the key area of the upper reaches of Bolshoi Mamai River, which is situated on the northern slope of the range. Tall-herb meadows occurred within a large altitudinal range from timberline to the watershed. We found that species richness was positively correlated with inclination and orientation of sites to warmer aspect. In contrast, strong pronounced microtopography and high organic layer thickness led to lower species richness. We divided the tall herb vegetation of the study region into seven community types, which clearly differed in ecological aspects. The results were approved by CCA or di nation, which stressed the relation of clusters to elevation, aspect, inclination, mic ro topography and organic layer.