WE USE THE QUANTITATIVE TOOLS OF SPATIAL ANALYSIS, MATHEMATICAL MODELING AND STATISTICS to explore ecological questions about the factors controlling nutrient discharges from watersheds, the role of wetlands in moderating nutrient transport, and the relationships between watershed geography and the health of wetland or stream ecosystems.

Human activities can concentrate and mobilize nutrients, like nitrogen and phosphorus. These materials are essential for all life, but cause environmental problems when overabundant. Excess nutrients released by agriculture, industry, and residential areas pollute and damage streams, rivers, and coastal waters. To understand and solve pollution problems, we need to know where and how nutrients enter the landscape and move through it to reach the aquatic systems.

To study the factors controlling nutrient transport, we use data from hundreds of study sites throughout the Chesapeake Bay watershed, including more than 30 years of data from sites at SERC's home in the Rhode River watershed. We use a geographic information system (GIS) to organize and summarize mapped data on watershed characteristics, and then apply statistical and mathematical models to relate those characteristics to measured nutrient losses. More recently, we have used similar geographic analyses to relate watershed characteristics to wetland condition and to stream health. Our results help identify simple indicators useful for predicting ecosystem health as well as nutrient transport.

We collaborate strongly with other SERC researchers and with scientists at other institutions. This team approach helps advance basic scientific understanding and provide knowledge essential for effective environmental management.

Dr. Donald Weller/ SeniorScientist

Smithsonian Environmental
Research Center

PO Box 28
Edgewater, Maryland 21037
Phone: 443-482-2214
Fax: 443-482-2380
Curriculum Vitae