Biological invaders can alter ecosystem processes via multiple pathways, yet few studies have compared the relative importance of these pathways. We assessed the impacts of exotic, invasive grasses on ecosystem nitrogen (N) cycling in the seasonal submontane woodlands of Hawaii Volcanoes National Park, where native grasses have been historically rare. Exotic grasses have become abundant over th...

Several methods exist for measuring forest canopies following disturbance, and the biases and differences among them are unclear. We compared techniques for measuring the northern hardwood forest’s canopy structure at the Hubbard Brook Experimental Forest, New Hampshire, following the severe ice storm of January 5–10, 1998. Methods included leaf area index (LAI) using LI-COR’s LAI-2000, visual ...

Application of meteoric 10 Be inventories and Be/ 9 ratios to determine surface ages, erosion rates, denudation rates requires understanding the conditions under which functions as an open vs. closed system near Earth's surface. Here, we investigate biologically mediated beryllium isotope mobility in oak-hickory forest eastern North America. We report concentrations soils, roots, leaves four de...

Abstract. Arctic warming and permafrost degradation are modifying northern ecosystems through changes in microtopography, soil water dynamics, nutrient availability, vegetation succession. Upon degradation, the release of deep stores nutrients, such as nitrogen phosphorus, from newly thawed stimulates production. More specifically, wetter lowlands show an increase sedges (as part graminoids), w...