Interdisciplinary Oceanography

microbes, optics, elements, and joyous exploration of the natural world

The scientific community is presently faced with the challenge of characterizing and predicting the behavior of the Earth system under the stresses of a changing environment. A primary focus of this effort is to understand the role of our oceans as regulators of the global cycling of water, heat and elements. As a microbial ecologist, my research has focused on the role of microbes in defining the function of ocean ecosystems and how this function may change in response to environmental pressures. My research skill set is broad, ranging from measurement of nutrient controls of primary productivity and nitrogen fixation to molecular characterization of organic matter to bio-optical estimations of microbial community structure and primary productivity. 

My research is supported by a diverse profile of external sources including the National Science Foundation, the National Oceanic and Atmospheric Administration, the National Aeronautics and Space Administration and private funding sources such as the Simons Foundation.

As is common in Oceanography, much of my work is interdisciplinary and collaborative. Vignettes of selected current funding are below

Follow my research and research interests on research gate or google scholar

Simons Collaborative on Ocean Processes and Ecology (SCOPE): The central mission of SCOPE is to measure, model and predict the pathways and exchanges (inputs and outputs) of energy and matter within and between specific microbial groups and their environment at relevant spatial and temporal scales, from surface waters to the deep sea (more than 4 km in depth) at Station ALOHA. Recent publications from this collaboration span diel cycles to diazotrophy.

Ocean Carbon Cycling (NSF): As is true for many coastal regions worldwide, the Pacific Northwest margin is characterized by intense seasonal contrasts in conditions controlling carbon flux between the atmosphere, land, and ocean. During the wintertime, rapid and intense flooding of small coastal rivers and the associated inputs of freshwater, nutrients, and organic matter are commonplace in the Pacific Northwest. Impacts of these wintertime terrestrial-ocean transfers by small, flood-prone rivers on the upwelling regions, such as the Pacific Northwest, have been underestimated at both global and regional scales. In order to gain a complete and predictive understanding of carbon cycling in ocean margins, the biogeochemistry of periods of intense terrestrial-ocean transfers needs to be comprehensively studied. This project will evaluate the dynamics of organic matter cycling along an upwelling-dominated margin during the wintertime period of active terrestrial inputs and biological cycling using a combination of shipboard, glider, moored and remote measurements.

NOAA- Monitoring Oregon's Coastal Harmful Algae (MOCHA): Integrated HAB monitoring and event response for coastal Oregon CenterPhycotoxins such as saxitoxin and domoic acid have had a significant impact on Oregon coastal communities and their economy for decades. In recent years, particularly 2003, 2005, 2010, and 2015, domoic acid and saxitoxin contamination has resulted in spatially large and prolonged closures of razor clam and mussel beds to harvesting. In the only economic assessment made to date for the region, the Oregon Department of Fish and Wildlife (ODFW) estimated that the cost of a domoic acid-related closure of the razor clam fishery at Clatsop Beach in 2003 alone cost the local communities $4.8 million. By partnering researchers from state universities and NOAA with representatives of agencies responsible for the state’s monitoring programs we have been able to develop an ecosystem-based approach to HAB monitoring and event response in Oregon. Our most recent findings were published in PNAS and highlighted by OCB .

C-MORE- Microplastic in the North Pacific: Among many highlights of the work funded by the National Science Foundation Center for Microbial Oceanography: Research and Education (C-MORE), I was a participant in research aimed at understanding the impact of plastic pollution on some of the ocean's smallest denizens: microbes.

Standing on the bow of a research ship, floating in the heart of the “Great Pacific Garbage Patch,” my colleagues and I looked out onto a calm, apparently pristine blue ocean. By towing a mesh net through these waters and deploying instruments capable of measuring particle size and abundance, it became apparent that the sea around us actually contained a dilute soup of very small pieces of plastic that were largely invisible to the naked eye. Below I've added an image of some of this plastic that was collected by a colleague (Charlie Miller) in 1971 in the North Pacific. We're still finding pieces like this on our coasts and in our oceans today. In a paper in the journal mSystems, we describe the diversity and activity of the microbes that use plastic as habitat.

Other research in my lab includes efforts to model ocean productivity using optical approaches; research to characterize elemental stoichiometry, and measurements of organic matter decomposition and ensuing methane production among other mysteries of the sea.