Effectively managing coastal ecosystems is essential to reach global conservation and climate goals, as these areas support biodiversity and critical ecosystem services that benefit human livelihoods. As a result, understanding the effects of anthropogenic influence on these regions is crucial for identifying conservation action that ensures the long-term persistence of important ecological coastal processes.
In a recent study, an international team of researchers found that as of 2013, only 15.5% of the earth’s coastal areas remained ecologically intact. The study, co-authored by Benjamin Halpern, the executive director of UC Santa Barbara’s National Center for Ecological Analysis & Synthesis, is the first to merge both terrestrial and marine human impact maps to find that no coastal region in the world is free from human influence – and that the coastal regions with high levels of human pressure were largely concentrated in tropical and temperate regions.
“Coasts are where the land meets the sea, and yet conservation and management almost always treat them separately,” said Halpern, who is also a professor in UCSB’s Bren School of Environmental Science & Management. “By evaluating them together, we helped identify where these connected land and seascapes are relatively untouched, and the many places where they are not.”
The findings are a stark reminder of both the heavy reliance humans have on the coast, and the dwindling amount of intact coastal area that we have left. “Coastal regions contain high levels of biodiversity and are relied upon by millions of people for ecosystem services such as food and storm protection,” said the study’s lead author, Brooke Williams, from the University of Queensland. “Our results show that urgent action is needed to conserve those coastal regions that do remain intact and restore those that are degraded, especially to help mitigate climate change.”
According to the study, coastal regions containing seagrasses, savannah and coral reefs had the highest levels of human pressure — a swath that encompasses most of Europe, Asia, Africa, the Americas and the South Pacific. The study also showed that in most coastal countries, more than 50% of their coastal regions were degraded, and that nearly half of protected areas across coastal regions were exposed to high human pressures.
The study highlights that Canada is responsible for the largest expanse of coastal region that remains intact, with other large areas also located in Russia, Greenland, Chile, Australia and the United States.
The analysis presented in this study can help identify the spectrum of human pressure at a broad scale to drive more localized assessments. “Understanding why coastal systems are under pressure can help us design and implement more targeted management strategies,” said co-author Amelia Wenger, a research fellow at UQ.
Researchers urge governments to proactively conserve the valuable remaining intact coastal regions that they are responsible for, while restoring those that are degraded. To facilitate and promote the conservation of these regions, the authors have made the dataset publicly available and free to use.
Further reading:
The Last of the Natural Coasts, The UCSB Current, 8 February 2022