An assessment of live hard coral cover distribution and its physicochemical factors in the Strait of Malacca from 1995 to 2016

The Strait of Malacca is well-known as an important trade route with high marine biodiversity. Among the organisms residing in the strait are the reef-building hard corals. Studies have shown that climate change and other anthropogenic stressors have induced severe degradation of coral reefs through the disruption of coral productivity and metabolisms. Moreover, in-depth investigations of causal inference of coral degradation and its correlations with potential coral-affecting physicochemical factors within the strait are limited. Hence, this study presents the analyses of the latest bi-decadal time-series trend from 1995 to 2016 of the live hard coral coverage (or live coral cover) and six coral-affecting physicochemical factors (significant wave height, sea surface salinity, particulate inorganic carbon, particulate organic carbon, turbidity, and sea surface temperature) using remote sensing and reanalysis datasets. Their potential correlations were interpreted by implementing meta- and statistical analyses of past coral surveys and remote sensing data. This study revealed the overall persistent bi-decadal decline in live hard coral coverage within the Strait of Malacca and the complex correlations among the factors that correspond to the spatial stratification of the marine environment. Among the six physicochemical factors, sea surface temperature, turbidity, and sea surface salinity were determined to be the most influential parameters on live coral cover distribution within the strait.