Limited directional change in mountaintop plant communities over 19 years in western North America

Plant communities on mountain summits are commonly long-lived, cold-adapted perennials with low dispersal ability. These characteristics in tandem with limited area to track suitable conditions make these mountain communities potentially highly vulnerable to climate change, and indicators of climate change impacts. We investigated temporal changes in plant communities on 29 arid mountain summits across eight study regions in California and Nevada, USA over 19 years. We analyzed community dynamics in terms of species richness, turnover, gain and loss of functional groups, and relative abundance of functional groups. First, across all summits and regions, we found no change in species richness over time. Second, there was relatively high species turnover (21.7%) between the five-year survey intervals, but turnover was not significantly different from random expectation. Within functional groups, forbs had the greatest proportion of gains and cushions had the greatest proportion of losses...., , , # Limited directional change in mountaintop plant communities over 19 years in western North America

Repository for code, data, and figures related to Goff et al. manuscript: \"Limited directional change in mountaintop plant communities over 19 years in western North America\"

## File Manifest:

### code:

04_richness_model_figure1d.R - Performs species richness analysis, including statistical analysis and creating manuscript Figure 1d.

05_turnover_binomial_model_figureS2_figureS4_tableS2.R - Performs turnover analysis, using a modified function \"turnover\" in the package code to compute turnover between pairs of sequential surveys on the same peak, and feeding this data into statistical analysis. These results are used to create supplemental Figure S2 and S4, as well as table S2

05A_modify_codyn_turnover.R - makes one small modification to the source code of codyn (Hallet et al. 2013), so that gains and losses are not proportional to the total species richness of a given replicate. Al...