Development of vegetation on barren and high elevation sites.

This study is a continuation of work begun in 1980. Current studies include monitoring permanent plots, monitoring grids, studying relict plots, assessing vegetation in potholes, and describing vegetation along transects. The plots studied to date can be divided into those that are fully recovered, those undergoing secondary succession and those undergoing primary succession. The rate of recovery, measured by the number of species and their cover, is related to proximity to sources of colonists and to habitat stress. The species composition of sites undergoing primary succession is related to proximity to intact vegetation and is strongly affected by distance and by chance effects. Previous studies have demonstrated that environmental factors only weakly predict species composition.


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