Abstract: We examined species composition, growth forms and synusia composition of the ground-dwelling bryophytes, as well as the relationship between the distribution of associations and environmental factors, in an artificial Pinus sylvestris var. mongolica forest in the southeastern region of the Hunshandake Sandy Land, through the construction of growth form system based on the morphology of individuals, cluster and ordination analysis of 16 forest plots. The results showed that there were 41 bryophyte species belonging to 25 genera and 14 families, which contained nine types of growth forms, mainly including small acrocarpous mosses (ten species), medium acrocarpous mosses (nine species), small pleurocarpous mosses (eight species) and large pleurocarpous mosses (six species). The two-way indicator species analysis (TWISPAN) revealed that the 16 plots could be divided into six groups, which contained 2-27 species, 1-9 growth forms, 1-4 synusia. The dominant synusia were small acrocarpous mosses, medium thallus liverworts, small pleurocarpous mosses (two groups), and large pleurocarpous mosses (two groups). The bryophyte associations were named after the dominant species in each synusia. Results from the canonical correspondence analysis (CCA) showed that annual average temperature, altitude, air humidity, soil moisture, light intensity, herbal coverage, annual average precipitation, tree coverage, and litter coverage were the factors affecting the distribution of ground-dwelling bryophyte associations in the artificial Pinus sylvestris var. mongolica forest in the Hunshandake Sandy Land.

Key words: ground-dwelling bryophyte, artificial Pinus sylvestris var. mongolica forest, growth form, synusia, distribution pattern, Hunshandake Sandy Land