Vegetation and its relation with climate conditions near the timberline of Beitai,the Xiaowutai Mts., Northern China ANALYSIS ON THE FLORA OF SEED PLANTS OF WUTAI MOUNTAINS, SHANXI A study on the flora of spermatophyte in Xiaowutai Mountains Difference of ecological dominance of meadow population on different tourism disturbance AN APPLICATION OF CLUSTERING ANALYSIS IN FOREST SITE CLASSIFICATION AND EVALUATION