New Developments in Ecological Hydrology Expand Research Opportunities

Interdisciplinary research efforts to integrate the ecological aspects of water with its physical and societal roles have a long history as well as some interesting new developments. Small, paired, experimental watersheds, with their long-term monitoring systems for data collection and their integrated ecosystem approach to analysis, have been at the center of recent advances. A study now under way at such watersheds could provide a common analytic framework in ecological hydrology. The study, funded by the National Science Foundation through the Long Term Ecological Research (LTER) network [Swanson and Franklin, 1988], is identifying interactions among vegetation, climate, and streamflow at sites that have been studied individually for decades (Figure 1). Work so far has concentrated on seasonal variations at Andrews, Coweeta, Hubbard Brook, Luquillo, and Casper Creek, which reflect a range of precipitation amounts, types, and timing, as well as a range of forest vegetation types (Figure 2). Initial results are available on the project's Web site at www.fsl.orst.edu/-post/hydro. The National Research Council [1991] has emphasized the ecological importance of the hydrologic cycle, saying it represents a fundamental physical template for biological processes. This template presents some of the best opportunities to search for general principles that may guide the organization of living communities. In order to adequately manage global water and aquatic resources, forests, agriculture, and human populations, we need a clearer understanding of ecological hydrology-the study of relationships among hydrologic, climatologic, and ecologic processes in a hu-