OOS 40-8
Forest soil biogeochemistry: Contributions of experimental forests and ranges
Soil is the matrix through which many important environmental transformations occur. Biogeochemical cycling is mediated through the soil, and understanding soil processes is critical to understanding biogeochemical cycling. Thus studies of soil biogeochemical cycling are often part of paired watershed studies, and have been an important part of long-term research on USDA Forest Service Experimental Forests and Ranges. In particular, understanding how carbon and nitrogen, and also phosphorus, sulfur and other essential plant nutrients cycle within the soil matrix is essential to being able to address questions of climate change impacts, ecosystem productivity, and water quality in ecosystems. Because soil erosion is a significant process in certain ecosystems, understanding how soil movement is related to these ecosystem properties is also critical.
Results/Conclusions
Soils research on experimental forests and ranges has focused on questions of erosion, nutrient cycling, ecosystem productivity, and pollutants, with much of the nutrient cycling research dealing directly with questions related to atmospheric deposition of various compounds and effects of forest management. Therefore, cycling of nitrogen, sulfur and carbon are highlighted using examples from Experimental Forests and Ranges of the USDA Forest Service. In addition, research has addressed issues of nutrient limitation of productivity – particularly nitrogen, phosphorus, and calcium limitations on tree growth and health. Research on cycling of metals such as aluminum and mercury has also revealed important insights into ecosystem processes. Finally, Experimental Forests and Ranges have been the sites of considerable research on soil physical processes (erosion, decomposition, etc.), which are important in biogeochemical cycling at a variety of scales.