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Mac Callaham

Dr. Mac A. Callaham, Jr. is the acting Director of the USDA Southeast Climate Hub.  Mac comes to the Hub from the USDA Forest Service Center for Forest Disturbance Science in Athens, GA, where he is a Research Ecologist and Team Leader.

Dr. Callaham has worked for 20+ years with Forest Service Research and Development.  His research broadly addresses questions in soil ecological responses to climate change and changing environmental conditions.  The work spans disciplines ranging from zoology and phylogeography to microbial ecology, biogeochemistry, invasion biology and ecosystem restoration with particular focus on soil responses to land management actions that are intended to simulate natural disturbance or to mitigate risks associated with climate change.  In 2010 he received a Fulbright Fellowship to work on forest restoration strategies in the Atlantic rainforests of southern Brazil, and in 2014 was appointed to a Visiting Professorship by the Chinese Academy of Sciences to visit the Northeast Institute of Geography and Agroecology in Changchun, China.  Dr. Callaham earned a PhD in Biology from Kansas State University, and a Master of Science degree in Agronomy from University of Georgia.

Mac Callaham


  • Acting Director
  • Research Ecologist


USDA Forest Service


320 Green Street
Athens, GA 30603-2044

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