2005 BES Annual Meeting Presentation and Poster Abstracts
Soil Respiration Along an Urban to Rural Gradient in the Mid-Atlantic United States.
K. George and Q. Holifield
Abstract: Soil respiration constitutes a major component of the global carbon cycle and is likely to be altered by climate change. However, there is an incomplete understanding of the extent to which various processes contribute to total soil respiration, especially the contributions of root and rhizosphere respiration. Capacities of roots and micro-organisms to produce CO2 can vary with time of year, and depend on other components of plants and ecosystems, but the extent of these trends is not known. It is also well documented that temperature and moisture affect the activities of roots and micro-organisms, but these dependencies are not quantified. Spatial variation of organic matter and plant cover induce temperature and moisture gradations that obscure direct response of soil respiration to irradiative forcing. Separation of spatial patterns from microclimate and substrate availability is vital to predict the response to global change. By measuring temporal and spatial patterns of soil CO2 flux across an urban-to-suburban- to-rural gradient from urban city centers, to a mature forest patch to cultivated farmlands.