摘要：The effect of environmental factors on the distribution of alpine plant community types has been extensively studied in Colorado. Much less attention has been paid to the effects of these factors within community types, however. Transects were placed in the alpine zone of Goliath Peak in the Front Range of the Colorado Rocky Mountains. Species presences were tallied in 1-m 2 rectangular plots. Fuzzy set ordination (FSO) was used to determine which environmental factors were responsible for changes in species composition. Most sites fell into the fellfield or dry meadow community types. Water availability, as indicated by elevation, estimated winter snow depth and, less strongly, soil texture, was a strong factor associated with changes in plant community composition, both within and among community types. Temperature, as indicated by aspect, was also associated with these changes. The lack of Kobresia myosuroides at Goliath Peak appears to be caused by snow depths too deep or too shallow for this species. FSO proved to be more effective when environmental factors were ordinated separately rather than sequentially, as originally suggested. This was confirmed by a Bray-Curtis ordination. A species-site biplot showed how species and sites can be displayed together on the same fuzzy set ordination.
