Is Forest Soil Calcium Depletion Real?
Scott Bailey, Research Geoecologist, USDA Forest Service, Northern Research Station Some long-standing controversies about the effects of acid deposition on forest soils in the eastern United States remain after decades of research. Watershed mass balance studies, such as those conducted at Hubbard Brook and Cone Pond, New Hampshire, suggest that calcium is the nutrient most likely to be depleted by leaching induced by acid deposition. Long term monitoring shows that inputs of calcium via atmospheric precipitation and mineral weathering are low compared with hydrologic outputs. Existence of depletion is also supported by cation exchange theory as well as laboratory and watershed manipulation experiments. However, direct evidence of base cation depletion in forest soils is rare, suggesting the need for enhanced monitoring of the critical soil resource. Dr. Bailey’s research focuses on interactions between geology, soils, and ecosystems. Current projects range in location from the Allegh
