干旱区生态环境知识资源中心

I examine the process of plant community colonization through a chronosequence study of permanent plots spanning 45 years on a 70-year-old subalpine earthflow in south-western Colorado, USA.

While local diversity and average density of vegetation remained stable throughout the study, the overall diversity increased through the early years of the study with little change over the past 20 years. A gradual shift in species composition occurred through time with species with good dispersal and stress tolerance abilities colonizing the site initially followed by more generalist species.

After over 70 years the disturbed communities remained distinct from adjacent relatively undisturbed areas in diversity, density, and species composition. Soil translocation experiments suggest that it is the severe microclimate of the earthflow which is limiting further colonization of the site.