New $798K Grant Funds Study of Marine Microorganisms’ Response to Ocean Acidification

September 11, 2014

Tim Lucas, 919-613-8084,

DURHAM, N.C. – Researchers at the Duke University Marine Lab in Beaufort, N.C., have received a $798,000 grant from the National Science Foundation (NSF) to study marine microorganisms’ response to increased ocean acidification.

Zackary Johnson, Arthur P. Kaupe Assistant Professor of Molecular Biology in Marine Science is principal investigator on the new three-year grant.  Dana Hunt, assistant professor of microbial ecology, is the co-principal investigator.

The grant, which starts Jan. 1, 2015, will support Johnson and Hunt’s study, “Ocean Acidification: Microbes as Sentinels of Adaptive Responses to Multiple Stressors: Contrasting Estuarine and Open Ocean Environments.” A team of researchers from Duke and the Georgia Institute of Technology will collaborate with Johnson and Hunt on the study.

Recent research has shown that the world’s oceans are acidifying faster today than at any time in the past 300 million years as a result of climate change.  When the carbon dioxide dissolves in seawater, it reduces the water’s pH and affects the ability of organisms to form calcium carbonate minerals that are the building blocks of many species’ shells and skeletons.

If current trends continue, experts predict that the mean ocean pH will decrease by about 0.2 units over the next 50 years. A drop of that magnitude could have far-reaching impacts on many ocean ecosystems and organisms, including microorganisms that provide essential ecosystem services such as primary production (photosynthesis) and organic matter turnover.

Johnson and Hunt’s team will examine how these microbes respond to increased acidity in combination with other environmental stresses such as increased temperature. A key focus of the study will be comparing the responses of microbes from coastal ecosystems to those from the open ocean.   

Past research by Johnson and Hunt has documented sharp, short-term spikes occurring in estuarine acidity, driven by changes in temperature, water flow, biological activity and other natural factors. These short-term spikes are taking place in addition to the long-term ocean acidification linked to human-caused climate change, and may be adding insult to injury to vulnerable coastal marine species.

The grant to Johnson and Hunt was part of $11.4 million in new grants awarded this month by NSF through its Ocean Acidification program as part of the foundation’s Science, Engineering and Education for Sustainability initiative.