Rising sea levels could make UK salt marshes disappear

A new study from Rutgers University has revealed that sea-level rise will have a negative impact on salt marshes across the United Kingdom by the end of this century. Furthermore, if climate change is not mitigated, salt marshes in some regions of England could be lost as soon as the year 2040.

Salt tidal marshes, also known as coastal wetlands, rank among the most vulnerable ecosystems on the planet. The research is focused on data from 800 salt-marsh soil cores.

The study is unprecedented in using the geological record of salt marsh losses in the past to predict how they will be vulnerable to sea-level rise in the future.

An international team of scientists led by Professor Benjamin Horton found that, in the past, rising sea levels steadily waterlogged salt marshes across the UK region, wiping out the vegetation that protects the marshes from erosion.

Study co-author Robert E. Kopp is a professor in the Department of Earth and Planetary Sciences at Rutgers-New Brunswick and the director of the Rutgers Institute of Earth, Ocean, and Atmospheric Sciences.

Professor Kopp explained, “By 2100, if we continue upon a high-emissions trajectory, essentially all British salt marshes will face a high risk of loss. Reducing emissions significantly increase the odds that salt marshes will survive.”

Professor Horton pointed out that salt marshes provide important ecosystem services.

“They act as a buffer against coastal storms to protect the mainland and a filter for pollutants to decontaminate our fresh water,” said Professor Horton. “We also lose an important biodiversity hotspot. Salt marshes are important transitional habitats between the ocean and the land, and a nursery area for fish, crustacea, and insects.”

“The take-home point from this paper is how quickly we are going to lose these ecologically and economically important coastal areas in the 21st century.”

Mangroves in tropical areas such as Singapore are just as vulnerable to sea-level rise as salt marshes.

“What is unknown is the tipping point that will cause a disintegration of mangroves to Singapore and elsewhere in Southeast Asia,” said Professor Horton. “We are currently collecting data to address the future vulnerability of mangroves to sea-level rise.”

The study was published in the journal Nature Communications.

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By Chrissy Sexton, Earth.com Staff Writer

Image Credit: Matthew Brain