Faculty & Staff

Department Chair


  • Debbie Chavarria, Program Assistant, (415) 422-6553
  • Megan Danielson, Lab Coordinator, (415) 422-4166




Tel:(415) 422-5445

Tracy Benning

Associate Professor

Dr. Benning's research interests include landscape ecology, biogeochemistry, urban ecology, and resource conservation and management. Her recent research focuses on the application of remote sensing GIS technologies in the study of tropical rainforests in Hawaii and riparian corridors in African savanna.

Tel:(415) 422-5702

John Callaway


Dr. Callaway's research focuses on wetland plant and soil ecology, restoration ecology, exotic species invasions, sediment processes, and potential impacts of sea-level rise. His recent work has focused on wetland restoration in San Francisco Bay and the Tijuana Estuary on the border of Mexico and California.

Tel:(415) 422 - 4712

Gretchen Coffman

Assistant Professor

Dr. Coffman is a restoration ecologist with research projects on wetland and riparian restoration in Mediterranean-­‐type and tropical climates in coastal southern California, the San Francisco Bay Area, the Central Valley of California, and Southeast Asia. She teaches undergraduate and graduate courses in applied ecology, environmental science, restoration ecology, wetland science, and ecosystem ecology, all involving labs and field studies. 

Tel:(415) 422-2831

Deneb Karentz


Dr. Karentz is a marine biologist with expertise in ultraviolet photobiology and plankton ecology. Much of her work has focused on the physiological and ecological consequences of Antarctic ozone depletion.

Tel:(415) 422-5842

William Karney


William L. Karney received his Ph.D. in Organic Chemistry from the University of California, Los Angeles.  Dr. Karney's teaching interests lie primarily in the areas of environmental chemistry and organic chemistry.  His research involves the use of computational chemistry to study organic reaction mechanisms, particularly the formation and rearrangements of polycyclic aromatic hydrocarbons.

Tel:(415) 422-5730

John Lendvay

Associate Professor

John M. Lendvay received his Ph.D. in Environmental Engineering from the University of Michigan. Dr. Lendvay's research interests focus primarily on community assessment of regional water quality.


Allison Luengen

Assistant Professor

Dr. Luengen's research at USF focuses on the cycling and bioavailability of trace metals. She frequently works in the San Francisco Bay and Delta, an estuary where there are elevated concentrations of many metals, including mercury.

Tel:(415) 422-5895

Thomas MacDonald

Associate Professor

Tom MacDonald received his Ph.D. from Stanford University. Dr. MacDonald's research focuses on designing computer simulations of problems of pollution migration and using the results to engineer systems to contain pollutants and prevent further spreading. He has also published his research on the neural network application for bioremediation. Recently he has co-authored papers dealing with environmental risk and the precautionary principle.

Tel:(415) 422-5986

Stephanie Ohshita

Associate Professor

Professor Ohshita works on energy-based solutions to multiple environmental problems-from local air pollution to global climate change-and combines engineering with tools from political economy and organizational analysis.  With a geographic focus on China, Japan, and the US, her research and teaching examine energy and carbon saving strategies; policy design and implementation; international cooperation; the diffusion of clean and efficient technology; emissions inventories; and risk management.

Tel:(415) 422-4316

David Saah

Associate Professor and Director of Geospatial Analysis Lab

Dr. Saah has been trained as an interdisciplinary environmental scientist with research interests in landscape ecology, ecosystem modeling, environmental accounting, remote sensing, and geographic information science (GIS). He has participated in research projects throughout North America, Asia, Africa, and the Middle East.


Calla Schmidt

Assistant Professor

Calla Schmidt received a PhD in Earth Science from the University of California, Santa Cruz. Her research spans physical hydrology and biogeochemistry and aims to understand the connection between hydrology and the biogeochemical cycling of nutrients.


Maggie Winslow

Assistant Professor

Dr. Winslow specializes in ecological economics, macroeconomics, and managerial economics.  Her past research examined the relationship between economics growth, democracy and environmental quality. Her current research focuses on valuing ecosystem services and alternative economics.