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Benjamin James Kramer, PhD

My research background primarily focuses on how climate change and eutrophication impact harmful algae in freshwater ecosystems. This has included determining how elevated temperatures as well as carbon dioxide levels, in tandem with nitrogen availability, impact the growth, toxin synthesis, and gene expression of cyanobacteria and other phytoplankton, particularly within the Great Lakes. 

The term "harmful algae" encompasses a broad, highly diverse number of organisms in marine and freshwater environments that significantly impact ecosystems and devastate human health and industries. As we are in an ever-changing world, it is critical we understand how aquatic ecosystems will respond to climate change and other anthropogenic stressors, particularly when it comes to primary production. My dissertation and postdoctoral work involved extensive research into determining the importance of carbon dioxide on harmful freshwater cyanobacteria and the greater phytoplankton community. Freshwater carbonate chemistry is poorly understood relative to that of marine systems, even in the Great Lakes, and it is critical we fill those gaps in our understanding in order to better diagnose how phytoplankton and other primary producers such as harmful algae will respond. Thus, my work has involved analytical techniques such as the measurement of N2-fixation, dissolved inorganic carbon levels, and cyanotoxins as well as molecular techniques (metagenomics, metatranscriptomics, and metabolomics). All of this work has been done using traditional and novel experimental as well as field methods.

*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government

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