Relationships between anatomy and climate in members of the subfamily Pooideae

Abstract

As climate continues to change, it will become increasingly important to accurately predict the landscape-level response of plant functional groups to climatic shifts. Relationships between vascular anatomy and climate distribution have been revealed in woody plant species, but little research has been done on this subject in the Poaceae family. These relationships were studied in 21 grass species from 5 genera in the subfamily Pooideae by analyzing their anatomical traits and climate data from each species' range. Analysis showed multiple correlations among anatomical traits, such as a positive correlation between the ratio of vessel wall thickness to vessel diameter (t/b ratio) with vein density. These relationships suggest that anatomical traits are closely linked to each other and to vein density, which may be confer some advantage or be in response to selective pressure. Some correlations between climate traits and anatomical traits were found, but the strength of these relationships was less than expected and were often the result of the interaction of multiple climate variables with a single anatomical variable. This may be because of broad, multi-year averaged data obscuring important temporal and spatial factors, as well as phenological variation across species not being accounted for. Future research should focus on microclimatic conditions species occupy and noting phenology for each species to better identify the climate conditions species are adapted to.