Review of methods for coral reef bleaching monitoring

Coral reefs are one of the most biologically diverse, valuable and fragile marine ecosystems on earth.In recent years, coral reefs around the world have been experienced bleaching resulting from anthropogenic activities, climate change and environmental pollution.Global warming and sea surface temperature anomaly induced coral bleaching events are the greatest threats to coral reefs.Coral reefs and associated tropical near-shore ecosystems have suffered massive, long-term decline in abundance, diversity, and habitat structure.Therefore, coral bleaching monitoring is of great importance to the management of marine ecosystem and the conservation of the biodiversity.This paper reviewed the monitoring methods of coral bleaching at home and abroad, which can be divided into three types, that is, in-situ observation, ecological monitoring and remote sensing monitoring methods.We introduced and commented briefly the principles, advantages and disadvantages of each method, and the development tendencies of the monitoring method in the near future were also given.Among the methods, the methodology based on remote sensed sea surface temperature has been the most widely used, but the accuracy of monitoring method needs to be improved for small scale coral bleaching.The monitoring of coral bleaching in the US and Australia started earlier and has been routinely operated in the world.In contrast, our country started relatively late and lagged behind in monitoring methods.