A study on the adaptation and restoration of warm water coral reef ecosystem in the context of global change

Warm water coral (hereafter, coral) reef ecosystem is one of the most representative ecosystems in tropical waters. This article reviews the longterm changes of warm water coral reef ecosystem and its hazard factors under the background of global change, including the impacts and risks of climate change and human activities, and summarizes the research progress of global change adaptability and restoration technology of coral reef ecosystem. The results show that: 1. over the past decades, coral reef ecosystem has experienced rapid degradation, including mass coral bleaching and death, significant decline of diversity and ecological function, which is mainly due to the impacts of ocean warming and human activities. 2. It is estimated that, at high greenhouse gas emission scenario such as RCP8.5, the South China Sea (SCS) is very likely to be 2 ℃ of warming above the preindustrial levels by the midcentury at current linear warming rate of China seas, indicating that the climate tipping point of coral reef ecosystem in the SCS is very close, i.e., more than 90%-99% of the corals are projected to disappear at 2 ℃ of global warming. 3. Since the 1980s, the climateinduced hazard effects of intensity, extent and duration from ocean warming, heat waves and super strong tropical cyclones on corals have significantly increased, and led mass coral bleaching and the loss of corals worldwide. At the same time, human activities such as destructive fishing and overfishing, logging and diving in coastal coral reef waters are not only local, but also global phenomenon, not only cause to damage on corals, but also increase the climate vulnerability of corals, making them more difficult to adapt to global warming. The analysis also shows that, in order to enhance the ability of coral to adapt to global changes, the study and practice on restoration and adaptation of damaged coral reef ecosystems have been carried out, mainly by means of asexual reproduction or combined with artificial matrix restoration, while sexual reproduction has been less used to restore damaged coral reefs. Recently, great progress has been made in the study on the adaptability of coral to heat resistance. Finally, this article discusses the restoration of damaged coral reef ecosystem and the related countermeasures in China.