John Taylor, Professor of Economics at Stanford University and developer of the "Taylor Rule" for setting interest rates | Stanford University
John Taylor, Professor of Economics at Stanford University and developer of the "Taylor Rule" for setting interest rates | Stanford University
A new study led by Stanford University researchers has explored the role of microbial communities in coastal groundwater and their response to infiltrating seawater. The research, published in Environmental Microbiology on December 22, focuses on how these ecosystems may be affected by rising sea levels.
"Beaches can act as a filter between land and sea, processing groundwater and associated chemicals before they reach the ocean," explained Jessica Bullington, a PhD student at the Stanford Doerr School of Sustainability and co-first author of the study. "Understanding how these ecosystems function is key to safeguarding their services in the face of sea level rise."
The study was conducted at Stinson Beach, north of San Francisco. This location was chosen because it represents a "high-energy" beach with limited previous microbiome studies. Researchers collected samples from the beach's subterranean estuary over two weeks during both wet and dry seasons. Using advanced gene sequencing techniques, they analyzed microbial DNA to understand community composition and stability.
Findings revealed that while microbial communities remained stable under typical tidal conditions and seasons, disturbances like wave overtopping events caused significant changes in microbial makeup. Such events are expected to increase with rising sea levels and storm surges.
"These microbes live in complex communities, many with specialized roles that include processing nutrients and even producing or consuming greenhouse gases," said Christopher Francis, a professor at Stanford Doerr School of Sustainability. Co-first author Katie Langenfeld added that while resilience under normal conditions is promising, disturbances highlight vulnerabilities due to climate change.
The study provides a baseline for understanding subterranean estuaries' responses to environmental changes. As sea levels rise, changes in groundwater hydrology could impact microbial composition and water purification capabilities.
Alexandria Boehm, another co-senior author, emphasized the importance of these findings: "We rely on these microbial communities for essential biogeochemical cycling at the land-sea interface. If their capacity diminishes due to climate impacts, we could see cascading effects on coastal water quality and marine life."
The research was supported by several institutions including the National Science Foundation and Stanford University.
For more information, contact Rob Jordan at rjordan@stanford.edu or (415) 760-8058.
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