Functional traits predict plant species' climate distributions across the Hawaiian Islands
Abstract
The selective pressure of the abiotic environment is expected to generate strong correlations between species' trait values and their native climate distributions. However, few tests have been made of this hypothesis across wide and biodiverse regions. The Hawaiian Islands are an ideal system to investigate trait variation across species arrayed along environmental gradients, and if species' climate variables can be predicted based on traits. We utilized a dataset of leaf, stem and whole plant traits relating to drought tolerance and gas exchange physiology, nutrient and isotope composition and anatomy for 35 species in two 4-ha plots on Hawaii Island from wet montane rainforest (Laupāhoehoe) and lowland dry forest (Pālamanui), to analyze correspondence with species' climate variables based on presence in ca. 3000 vegetation plots across the Hawaiian Islands. We found very strong associations of species' traits with native climate, as expected based on adaptation for resource capture and stress tolerance. For example, species distributed in drier climates had higher leaf vein length per area, higher wood density, lower turgor loss point, lower carbon isotope discrimination, higher foliar N:P ratio, and lower stomatal index and stomatal conductance (r values -0.53 to -0.72; P < 0.001 to 0.01). We present statistical models predicting native climate distributions for species across the Hawaiian Islands, and apply these models to generate maps of geographical trait distributions. The resolution of species' climate distributions based on traits will provide a foundation for conservation and ecological restoration. Further, these models provide an avenue to predict how distributions of species and functional groups may shift under climate change.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.B44D..05S
- Keywords:
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- 3305 Climate change and variability;
- ATMOSPHERIC PROCESSES;
- 0414 Biogeochemical cycles;
- processes;
- and modeling;
- BIOGEOSCIENCES;
- 1631 Land/atmosphere interactions;
- GLOBAL CHANGE;
- 1813 Eco-hydrology;
- HYDROLOGY