This volume is a series of papers summarizing the results of the Experimental Watershed Liming Study (EWLS). The EWLS was initiated in 1989 to investigate the application of calcium carbonate (limestone) to upland and wetland forests as a strategy to mitigate the acidity of lake water and improve fisheries. Woods Lake, in the Adirondack region of New York U. S. A. , is the site of long-term studies of surface water acidification. This whole-ecosystem manipulation was designed to be a comprehensive evaluation of the chemical and biological response of uplands, wetlands and surface waters to calcium carbonate treatment. A multidisciplinary project team conducted this investigation, including researchers from Clarkson University, Cornell University, the Institute for Ecosystem Studies, Smith College, EWLS was conceived by Syracuse University and U. S. Geological Survey. The Bob Brocksen and others from Living Lakes Inc. and Don Porcella of the Electric Power Research Institute. Financial support for the EWLS was provided by Living Lakes Inc. , the Electric Power Research Institute, the Empire State Electric Energy Research Corporation, the U. S. Fish and Wildlife Service and the U. S. Geological Survey. vii Biogeochemistry 32: 143-174, 1996. (c) 1996 Kluwer Academic Publishers. The Experimental Watershed Liming Study: Comparison of lake and watershed neutralization strategies 1 4 C. T. DRISCOLU, C. P. CIRM0 ,2, T. J. FAHEy3, V. L. BLETTE , 6 1 P. A. BUKAVECKAS5, D. A. BURNS , C. P.

Knowledge in the field of acidic deposition is expanding rapidly, and both ex perts and non-experts are challenged to keep up with the latest information. We designed our assessment to include both the basic foundation needed by non experts and the detailed information needed by experts. Our assessment in cludes background information on acidic deposition (Chapter 1), an in-depth discussion of the nature of soil acidity and ecosystem H+ budgets (Chapter 2), and a summary of rates of deposition in the Southeastern U.S. (Chapter 3). A discussion of the nature of forest soils in the region (Chapter 4) is followed by an overview of previous assessments of soil sensitivity to acidification (Chapter 5). The potential impacts of acidic deposition on forest nutrition are described in the context of the degree of current nutrient limitation on forest productivity (Chap ter 6). The results of simulations with the MAGIC model provided evaluations of the likely sensitivity of a variety of soils representative of forest soils in the South (Chapter 7), as well as a test of soil sensitivity criteria. Our synthesis and recommendations for research (Chapter 8) also serve as an executive summary. A complementary volume in the Springer-Verlag Ecological Studies series should be consulted for information on European forests. This volume, Acidic Deposition and Forest Decline in the Fictelgebirge, edited by E.-D. Schultze and O.L. Lange, also provides greater detail on the physiologic responses of trees than we present in our regional assessment."