James E. Gawel

Sustainable Watershed Management: An International Multi-watershed Case Study

Abstract Global freshwater resources are being increasingly polluted and depleted, threatening sustainable development and human and ecosystem health. Utilizing case studies from 4 different watersheds in the United States, Japan, Switzerland, and Brazil, this paper identifies the most relevant sustainability deficits and derives general vectors for more sustainable water management. As a consequence of the demographic and economic developments experienced in the last few decades, each watershed has suffered declines in water quality, streamflow and biotic resources. However, the extent and the cultural perception of these water-related problems vary substantially in the different watersheds, leading to specific water-management strategies. In industrialized countries, exemplified by the US, Switzerland, and Japan, these strategies have primarily consisted of finance- and energy-intensive technologies, allowing these countries to meet water requirements while minimizing human health risks. But, from a sustainability point of view, such strategies, relying on limited natural resources, are not long-term solutions. For newly industrialized countries such as Brazil, expensive technologies for water management are often not economically feasible, thus limiting the extent to which newly industrialized and developing countries can utilize the expertise offered by the industrialized world. Sustainable water management has to be achieved by a common learning process involving industrialized, newly industrialized, and developing countries, following general sustainability guidelines as exemplified in this paper.

Designing Undergraduate Research Experiences for Nontraditional Student Learning at Sea

The environmental science curriculum at the University of Washington, Tacoma (UWT) is based on an experiential learning model that enhances undergraduate education by involving students in ongoing research projects that extend beyond the classroom into the broader scientific community. Nontraditional student learning is especially enriched by access to unique hands-on field experiences that foster a sense of scientific ownership. During the summers of 2001 and 2002, undergraduate students from UWT participated in two very different marine research courses designed by environmental science faculty. By comparing these two course designs, we have identified two primary issues of importance when setting up a field research program at sea. First, learning outcomes are dependent on the platform chosen for the research cruise, and thus the vessel to be used must be considered when designing a curricular model. Second, planning and implementation considerations need to be addressed regardless of the platform chosen. Planning challenges include early advertising, minimizing costs, and scheduling for nontraditional students; while implementation considerations include research group configurations and the structure of the post-cruise working environment.

Increased Exposure of Plankton to Arsenic in Contaminated Weakly-Stratified Lakes

Arsenic, a priority Superfund contaminant and carcinogen, is a legacy pollutant impacting aquatic ecosystems in urban lakes downwind of the former ASARCO copper smelter in Ruston, WA, now a Superfund site. We examined the mobility of arsenic from contaminated sediments and arsenic bioaccumulation in phytoplankton and zooplankton in lakes with varying mixing regimes. In lakes with strong seasonal thermal stratification, high aqueous arsenic concentrations were limited to anoxic bottom waters that formed during summer stratification, and arsenic concentrations were low in oxic surface waters. However, in weakly-stratified lakes, the entire water column, including the fully oxic surface waters, had elevated concentrations of arsenic (up to 30μgL-1) during the summer. We found enhanced trophic transfer of arsenic through the base of the aquatic food web in weakly-stratified lakes; plankton in these lakes accumulated up to an order of magnitude more arsenic on multiple sampling days than plankton in stratified lakes with similar levels of contamination. We posit that greater bioaccumulation in weakly-stratified lakes was due to elevated arsenic in oxic waters. Aquatic life primarily inhabits oxic waters and in the oxic water column of weakly-stratified lakes arsenic was speciated as arsenate, which is readily taken up by phytoplankton because of its structural similarities to phosphate. Our study indicates that mobilization of arsenic from lake sediments into overlying oxic water columns in weakly-stratified lakes leads to increased arsenic exposure and uptake at the base of the aquatic food web.

The New Spirit Lake: Changes to Hydrology, Nutrient Cycling, and Biological Productivity

Spirit Lake was changed biologically, chemically, and physically by the 1980 eruption of Mount St. Helens and the concurrent landslide that essentially buried the old lake and created a new one in its place. Recent changes to the surrounding watershed, spurred by ever-increasing regrowth of terrestrial vegetation, continue to alter the biogeochemistry of Spirit Lake. Here the authors outline over a decade of work developing a hydrologic and nutrient model for the lake and discuss preliminary work to elucidate the ecological role of the floating logs in Spirit Lake.