Differences in forest plant functional trait distributions across land-use and productivity gradients

Abstract

• Premise of study: Plant functional traits are commonly used as proxies for plant responses to environmental challenges, yet few studies have explored how functional trait distributions differ across gradients of land-use change. By comparing trait distributions in intact forests with those across land-use change gradients, we can improve our understanding of the ways land-use change alters the diversity and functioning of plant communities. • Methods: We examined how the variation and distribution of trait values for seven plant functional traits differ between reference natural forest and three types of land-use conversion (pasture, old-field, or "legacy" sites-regrowth following logging), landscape productivity (NPP) and vegetation strata (tree or non-tree "understory"), in a meta-analysis of studies from 15 landscapes across five continents. • Key results: Although trait variation often differed between land-uses within a landscape, these patterns were rarely consistent across landscapes. The variance and distribution of traits were more likely to differ consistently between natural forest and land-use conversion categories for understory (non-tree) plants than for trees. Landscape productivity did not significantly alter the difference in trait variance between natural forest and land-use conversion categories for any trait except dispersal. • Conclusions: Our results suggest that even for traits well linked to plant environmental response strategies, broad classes of land-use change and landscape productivity are not generally useful indicators of the mechanisms driving compositional changes in human-modified forest systems.

Citation

Mayfield, Margaret M.; Dwyer, John M.; Chalmandrier, Loic; Wells, Jessie A.; Bonser, Stephen P.; Catterall, Carla P.; DeClerck, Fabrice; Ding, Yi; Fraterrigo, Jennifer M.; Metcalfe, Daniel J.; Queiroz, Cibele; Vesk, Peter A.; Morgan, John W. 2013. Differences in forest plant functional trait distributions across land-use and productivity gradients. American Journal of Botany 100(7):1356-1368. DOI: 10.3732/ajb.1200461.