OHSU

EBS Welcomes Two New Faculty Members

02/01/08 Portland, Ore. 

The Department of Environmental and Biomolecular Systems at Oregon Health & Science University is pleased to welcome two new faculty members: Joseph Needoba, Ph.D., and Tawnya Peterson, Ph.D.

Joseph NeedobaNeedoba has accepted a position as Assistant Professor in the department, and is jointly appointed at the Center for Coastal Margin Observation and Prediction (CMOP). Peterson has accepted a position as Research Assistant Professor and also holds a joint appointment at CMOP.

After completing his Ph.D. in Botany (University of British Columbia, 2003), Needoba accepted a three-year appointment as a postdoctoral fellow at the Monterey Bay Aquarium Research Institute (MBARI) in Moss Landing, California. He remains a collaborative researcher at MBARI.

Needoba's research links nutrient biogeochemistry with primary productivity and plant physiology, with a particular focus on the nitrogen cycle in aquatic ecosystems. In addition to lab culturing of marine phytoplankton, natural abundance stable isotope techniques, and shipboard incubation experiments, he has developed nutrient sensors for use on remote platforms.

The focus of Needoba's dissertation was better understanding the constraints on nitrogen isotope fractionation in marine phytoplankton, and the research he conducted for it was fundamental for the interpretation of stable nitrogen isotope signatures in environmental science and oceanography. One manuscript he produced during his dissertation work is listed among the most-cited research articles in the Journal of Phycology for 2003-2006.

At MBARI, Needoba led implementation of the Land/Ocean Biogeochemical Observatory in Elkhorn Slough, California, where his responsibilities included the development and deployment of moored instruments producing high resolution measurements of nutrient cycles.

That project--one of the foremost examples of using sensor networks to advance biogeochemical understanding in coastal environments--is a natural prelude to Needoba's joint appointment at CMOP, one of the goals of which is to develop new remote sensing technologies to accumulate extremely rich data sets across ecosystem scales. A key barrier in using these technologies is their stability and endurance, and at OHSU Needoba's research will contribute to improvements in sensors as well as to understanding of coastal ecosystems. In addition, his work at the confluence of chemistry, geology and biology is an interdisciplinary fit that extends the scope of the department in significant ways.

Tawnya PetersonAfter completing her Ph.D. in Oceanography (University of British Columbia, 2005), Peterson received a National Science and Engineering Research Council of Canada fellowship to conduct post doctoral research at the University of California, Santa Cruz. During her tenure at UC Santa Cruz she also served as a lecturer in the Ocean Sciences department..

Peterson's research focuses on the factors that control biologically mediated carbon and nutrient dynamics in the ocean. As she points out, about 50 percent of global carbon fixation comes from marine algae and photosynthetic bacteria; understanding how they interact with their environment is essential. She combines expertise in phytoplankton ecology and physiology with a broader goal of identifying factors that account for environmental variability.

The focus of Peterson's dissertation was the evolution of phytoplankton communities within oceanic eddies in the Gulf of Alaska. She was especially interested in how physical and chemical changes affected biological communities, and her research demonstrated that eddies maintain phytoplankton populations distinctly different from the surrounding ocean in part because of the physical properties involved in the coalescence of newly formed and older eddies.

In her postdoctoral work, Peterson has engaged in multiple collaborations focused on primary production, bio-optics, assemblage structure, and nutrient uptake kinetics in various coastal and open-ocean environments. One significant project involved the development of a new model of an inexpensive variable fluorescence meter, undertaken with research scientists at Turner Designs.

At OHSU, Peterson will continue working with technologies to improve understanding of biological variability in the ocean, particularly with those deployed on remote observation platforms like those being developed for CMOP. With a primary focus on phytoplankton, she is particularly interested in the integration of biological data with physical and chemical characteristics. That pursuit of integration is consonant not only with the goals of CMOP, but also reflects the highly integrative approach of a department devoted to understanding environmental and biomolecular systems.