Physiological and anatomical trait variability of dominant C4 grasses.

Abstract Climate variability is a key driver of physiological responses in common grass species in grasslands of North America. Differences in microanatomical traits among coexisting species may influence physiological responses to climate variability over large geographic scales. The goal of this research was to determine leaf-level physiological and microanatomical trait variability among four dominant C 4 grass species across a natural precipitation gradient. Physiological traits were observed to vary significantly across the gradient with greater variability than microanatomical traits. Microanatomical traits were shown to predict physiological responses in A. gerardii and P. virgatum , but the nature of the relationships varied between species. These results illustrate that microanatomical and physiological traits vary across a precipitation gradient, there are clear linkages between microanatomy and physiology in grass species, and this evidence underscores the need for further investigation using phylogenetically diverse assemblages. Highlights • Physiology and microanatomy in C 4 grasses varies across precipitation gradients. • Within species, trait variability is low within individual locations. • Microanatomical traits did not vary significantly over the growing season. • Grass physiology can be predicted by species – specific microanatomical traits. [ABSTRACT FROM AUTHOR]