Plant functional traits often show strong correlations to environmental gradients, however this knowledge is infrequently applied to the study of restoration ecology. Using a restoration treatment database for the Colorado Plateau, USA, spanning 1999-present we analyzed the independent and interactive effects of functional traits and local climate on restoration success of seeded species, quantified as an increase in cover or density compared to pre-treatment monitoring. We obtained data for three plant functional traits: seed mass, height and, specific leaf area and 6 climate variables for a window of two years post-treatment at each site. Using generalized linear models with a log-link function, we tested each explanatory variable against the response variable of success.
Results/Conclusions
Strong trait-environment interactions demonstrated the need to match traits of species to suitable environments. Seed mass had significant interactions with temperature seasonality, precipitation seasonality, and precipitation of warmest quarter. Though overall, medium to large seeds are more successful in the region, areas with high precipitation seasonality favored smaller seeds instead. Plant height had a significant interaction with annual mean temperature, temperature seasonality, and annual precipitation. Whereas shorter plants overall were more successful regionally, the interaction reveals environments where taller plants are more successful such as areas with high temperature seasonality. We also found that specific leaf area and precipitation of the warmest quarter had a significant interaction; species with lower specific leaf area do best in areas with high summer precipitation. These interactions lend insight to selecting seed mixes for restoring areas with specific environmental conditions.