Abstract
The impacts of global climate change on below-ground processes, especially plant-soil responses to elevated carbon dioxide and temperature, are studied. Some complex climatic-edaphic interactions are examined to illustrate the difficulty of predicting ecosystem responses to global change. At the ecosystem level, increased atmospheric CO sub(2) could induce increased root production, exudation of carbon into the soil, production of secondary metabolites, and nitrogen availability. Conversely, increased soil temperature could induce accelerated root and soil respiration, causing a CO sub(2) flux back into the atmosphere. The impacts of these combined effects on soil biological processes remain uncertain.