Can Functional Traits Explain Recent Changes in Abundance of Alpine Plant Species?

Climate change is driving significant changes in alpine ecosystems, where temperature-sensitive plant communities are particularly vulnerable. As plants migrate to higher elevations, understanding the mechanisms behind these changes is critical for predicting ecosystem dynamics. Morphological, physiological, and chemical functional traits may help understand species' responses to environmental change. This study examines whether functional traits can explain recent changes in presence and cover of alpine plant species in permanent plots. We analyzed vegetation data from repeated surveys of permanent plots at two sites. Morphological traits (e.g., plant height, leaf area) and physiological traits (e.g., frost and drought resistance) were measured locally for common species and supplemented with data from the TRY trait database to broaden species coverage. Linear models were applied to assess the relationships between traits and abundance changes (presence and cover), using multiple metrics. Our results reveal that plant height and leaf area are significant predictors of species abundance changes, emphasizing the role of morphological traits in shaping alpine plant communities. In contrast, physiological traits showed limited explanatory power. Notably, leaf carbon content emerged as a key predictor, suggesting that conservative strategies may provide advantages under warming conditions. Measures describing biomass dynamics (e.g., cover) differed from those describing establishment (e.g., presence), highlighting the multifaceted nature of species responses to environmental changes. Although our findings emphasize the importance of competitive interactions and resource acquisition, the study is limited by the absence of traits related to heat tolerance and prolonged warming. Future research should address these gaps to better understand the impacts of sustained temperature increases on alpine ecosystems.