JEJU, Jun. 12 (Korea Bizwire) – A troubling phenomenon known as sea desertification, where ocean floors become devoid of marine life, is intensifying in waters surrounding South Korea’s Jeju Island, according to a recent survey.
The 2023 Village Fishery Resource and Ecological Environment Report by the Jeju Marine and Fisheries Research Institute revealed severe sea desertification across all depth levels near Sincheon-ri in Seogwipo’s Seongsan district. Areas between 4 and 8 meters deep near Wimi 2-ri in Namwon also exhibited advanced stages of the problem.
Other sites showing marked signs of sea desertification included 4-meter depths off Hahyo-dong in Seogwipo, 8-meter depths near Ilgwa 2-ri in Daejeong, and 4-meter depths by Gonae-ri in Aewol, Jeju City.
Sea desertification occurs when once-lush marine forests on coastal rock beds are overrun by calcifying organisms like coralline algae, rendering the seascape barren like a desert. The phenomenon is being exacerbated by rising ocean temperatures driven by global warming.
Sites are classified as normal if less than 40% affected, progressing between 40-80%, and severe above 80% sea desertification. The survey found the condition was progressing at Gosan-ri, Beophwan-dong, Iho-dong, Ilgwa 2-ri, Chuja, and Pyeongdae.
Subtropical attached corals like Dendrophyllia and Pocillopora are expanding their range across most of Jeju, except the northeastern Gujwa area and Chuja, with subtropical species becoming more prevalent in southern regions.
The study identified 156 species of algae (25 green, 26 brown, and 110 red) thriving along Jeju’s coasts. While key food sources like brown algae declined, calcifying red algae accounted for 70% of the total.
The institute hopes this survey’s insights into changing coastal ecosystems will guide conservation efforts. The report is publicly available on its website, and the institute is also conducting detailed monitoring of marine pollution impacts from agricultural runoff this year.
M. H. Lee (mhlee@koreabizwire.com)
