2010 SBI Summer Workshop

July 21, 2010 -- LaSells Stewart Center, OSU

The Subsurface Biosphere Initiative held its sixth annual workshop on July 21 at the LaSells Stewart Center.  As in years past, the event was a forum for researchers from different scientific disciplines to share their studies of microbes living in soils and groundwater.  The researchers described experiments and analyses carried out at microscopic scales, but their projects had relevance for two large scale issues – the role of subsurface microbes in global nutrient cycling and their potential uses for engineering applications such as water treatment. 

Talks in the first category focused on soil microbes and the work they do to degrade organic matter and process critical nutrients.

• Steve Perakis, a research scientist with the USGS in Corvallis, spoke about nitrogen in soils of the Oregon Coast Range. Dr. Perakis explained that Coast Range soils are some of the most nitrogen rich soils on the planet and he described modeling studies aimed at understanding how forest succession, fire and other forest processes create the nitrogen abundance observed.

• Marco Keiluweit, a graduate student in soil science, spoke about processes taking place at the minute scale of individual soil particles.  He is using cutting edge imaging and chemical analysis techniques to visualize how the distribution of nitrogen and carbon change across the interface between mineral and organic particles.  He hopes that these images and related chemical data will help explain how microbes process these nutrients.

• Luis Sayavedra-Soto, research faculty in Botany and Plant Pathology, gave an overview of OSU research on Archaea, a group of microscopic organisms first recognized as a separate domain of life in the 1970’s.  The organisms are so small and difficult to culture that little is known about their physiology and it was only in 2005 that researchers realized that the tiny organisms play a role in the global nitrogen cycle.

Talks in the second category focused on engineering applications.

• Kelsey Yee, a student in chemical engineering, described her dissertation studies of an enzyme that degrades the wood constituent called lignin and could one day help convert wood products to biofuels.  The enzyme occurs naturally in a fungi that grows on decaying trees. Kelsey’s research focuses on artificial production of commercial quantities of the enzyme.

• Mohammed Azizian, research faculty in environmental engineering, spoke about microbes that can degrade the toxic compound TCE and its daughter products.  His team's goal is to identify microbial cultures, substrates and chemical conditions that promote the most rapid and sustained degradation of the highly toxic contaminant.

• Hong Liu, assistant professor of biological and ecological engineering, spoke about her studies of microbial fuel cells.  Her goal is to use microbes to generate electricity and hydrogen.  She described future applications such as a small sewage treatment system powered by the bacteria found in wastewater itself.

• Environmental engineering professor Dorthe Wildenschild’s talk focused on biofilms, webs of cells that can grow in the pore space between sand or soil grains.  Biofilms are of commercial interest because they can clog filters and affect the rate of bioremediation and even subsurface oil recovery.  Dorthe’s research group is developing cutting edge imaging techniques to study how biofilms grow. 

• Several other environmental engineering students and faculty spoke about other applications.  Nate Fulton described biosand filtration – a low cost, point of use technology to purify drinking water.  Jeff Nason and Tyler Radniecki spoke about nanoparticles – minute particles gaining increased use in consumer products, but without significant study of their environmental effects.

• Oceanography professor Rick Colwell ended the workshop with a discussion of the storage of carbon dioxide in basalts, a proposed method for removing the greenhouse gas from the atmosphere.

The evening poster session provided a forum for continued discussions.  One attendee commented, “the best aspect of the workshop is the juxtaposition of biologists with their insight into life history and physiological processes, and engineers with their focus on application.  It makes for an engaging exchange of ideas.”