The coral reef ecosystem in the waters off the Xisha Islands, part of China's southernmost island city of Sansha, remains healthy in 2018, a government report showed Wednesday.

The Ecological Environment Department of Hainan Province published a communique on the region's marine environment for 2018, noting that besides the healthy coral reef ecosystem, the quality of water, sediment and creature in the waters is generally in good condition.

Coral reef, South China Sea. [File photo: IC]

The institutions in the province carried out monitoring of the marine environmental quality and marine biodiversity in the waters under its jurisdiction in 2018. The monitoring of the coral reef ecosystem in six bodies of water, including the Xuande Islands and Yongle Islands, located in the Xisha Islands, was included.

The report said there are 49 species of corals in the waters and the coral reefs there are relatively rich in fish resources, with an average density of 70.23 fish per hundred square meters.

Australian Scientists predicted in a statement in October that even if global warming is limited to 1.5 degrees Celsius by 2050, coral reefs are still likely to decline by as much as 70 percent to 90 percent under the changing marine environment with higher temperatures affecting their growth.