Print PagePlant traits are a fundamental axis of variation between species and reflect basic trade offs in plant life history. Shifts in the distribution of community level plant traits over environmental gradients can inform us about important ecological processes such as abiotic filtering or competition. Understanding the relationship between plant traits and the environment may be especially important in ecosystems vulnerable to climate change, such as high elevation ecosystems. Here we assembled spatially explicit functional trait data on plant species of the subalpine zone around the Rocky Mountain Biological Lab in Gunnison County, CO, USA. Data were collected by many researchers over many years, and included phenological, floral, and physiological traits, as well as abundance and biomass data. We used this database, which contains both classically informative and also novel plant traits, to determine whether traits with different ecological roles covary. We also explored community level plant trait distributions and analyzed the shifts in these distributions over an elevational and climatic gradient.
Results/Conclusions
Data were collected for more than 130 plant species, on over 30 plant traits, comprising thousands of individual observations. For 32 species with completely sampled trait data we examined correlations within and between two phenological, three floral and five physiological traits. We found strong correlations between traits within ecological suites, i.e. within phenological, floral and physiological traits, but not between these suites. This suggests that phenology, floral morphology and physiology may be independent systems, and not part of a covarying plant trait spectrum. We also analyzed shifts in plant traits over elevation and climatic gradients by calculating the first four moments of the community trait distribution for a suite of nine floral morphological characters and six plant functional traits. Most notably, we found that leaf nutrient ratios (C:N:P), specific leaf area (SLA) and floral display volume were the most responsive to changes in climate. Furthermore, we find significant shifts in the variance, skew and kurtosis of community trait distributions with climate. This suggests that climatic factors do not simply influence the mean functional trait values, but also the distribution of those traits in communities. This database will be made available to the academic community and high schools for educational purposes.
