Bopaiah Biddanda, Ph.D.

Research Scientist
Environmental Biology

Bopi is an aquatic microbial ecologist with a background in oceanography and limnology. His goal is to understand the role microorganisms play in mediating the journey of carbon (aquatic carbon is a major reservoir of reactive carbon in the biosphere) and associated bioactive elements in the aquatic environment. In recent decades, there has been an explosion of ideas and research regarding the importance of microbial life on our planet. For example, it is now recognized that inconspicuous microbes drive many ecosystem level processes (including bulk of aquatic metabolism) which has fundamentally changed how we perceive the movement of energy and materials. Bopi argues that knowledge of how land, water and the atmosphere link together, and how microorganisms and metazoans interact, are critical to our understanding of how energy and materials (including pollutants) circulate in nature.

Bopi works at the interface between microbiology and biogeochemistry in both freshwater and marine ecosystems. Some of his recent findings are:

1. Microbial biomass and activity dominate in oligotrophic relative to eutrophic waters
2. Heterotrophic bacteria and phytoplankton link terrigenous (land) primary production to primary and secondary production in the water
3. Exposure to sunlight (UV radiation) modifies the bioavailability of dissolved organic matter in natural waters affecting carbon flux
4. Variability in bacterial growth efficiency across productivity gradients may explain the mechanism of contaminant accumulation within food webs
5. Warmer waters support enhanced bacterial respiration rates - suggesting a potential positive feedback loop to ongoing climatic change
6. Submerged sinkhole ecosystems in Lake Huron are biogeochemical hotspots of microbial and geochemical activity.

Another recent finding of importance has been the observation that even very large lakes (such as Lake Michigan) benefit from terrestrial subsidies, indicating close linkages between land and water everywhere.

Scott Kendall on board R/V Laurentian exploring submerged sinkhole ecosystems

The general focus of his research in recent years has been on how autotrophs and heterotrophs are coupled together in the aquatic environment and the importance of microorganisms in driving carbon, nitrogen and phosphorus cycles across biogeochemical gradients. Specific areas of his current research interests are: balance between autotrophs and heterotrophs in ecosystems, biogeochemistry of carbon, microbial and photochemical transformation of organic matter, microbial metabolism and bioaccumulation of pollutants, response of microbes to global climate change, and land-water linkages. At AWRI, Bopi has established a working research program in Aquatic Microbial Ecology and Biogeochemistry (to address basic questions such as: who is there? what are they doing? how fast are they doing it?) that will complement ongoing research and education efforts at GVSU. In his

Eric Strickler (undergraduate student) sampling rivers of West Michigan

research work, classroom teaching, seminars and publications, he continues to draw attention to the disproportionately large role that small microbes play in driving the large-scale biogeochemical cycles in nature.

For more information about Bopi, visit his faculty page.

Thomas Garry Sanders (graduate student) preparing ROV for a dive over submerged sinkholes