Alpine soil islands plant species composition, 2024.

High alpine ecosystems are particularly sensitive to climate-driven change, with vegetation expansion increasingly observed in historically barren soils. In late August and early September 2024, we revisited 50 previously established vegetation plots in Green Lakes Valley (Niwot Ridge LTER) to evaluate patterns of plant colonization and community change over time. Using legacy vegetation data from 2008 and 2015, we assessed changes in plant cover and composition in relation to microtopography and prior plant occurrence. We resampled plots using spatially referenced 1-meter radius surveys, estimating species incidence and cover while documenting moss, lichen, sedge, and grass diversity. These data can provide insight into how priority effects and fine-scale environmental variation influence alpine plant community dynamics and may inform predictive models of plant responses to ongoing climatic shifts.