Small experimental watersheds in the eastern United States, which define practical ecosystems, are used to study and evaluate (1) the impact of anthropogenic emissions on individual ecosystem processes and (2) the integrated response of the total system. The watershed approach to evaluating biochemical processes integrates several long- and short-term studies. This study evaluates chronic rather than acute effects. Therefore, two study areas were prepared so that an impacted area could be compared with a background area. The Cross Creek watershed has been subjected to about 30 years of sulfur and nitrogen input from the Widows Creek coal-fired power plant. The Camp Branch watershed, located in a relatively remote area, away from the influence of any major anthropogenic sulfur or nitrogen source, is being used to represent background conditions. A comparative study of these two sites is made. The objectives of the project, the facilities that have been developed, and the ecological characteristics of each watershed are described.

On cover: Camp Branch and Camp Cross experimental watershed projects. Includes bibliographical references (p. 56-57).