Reefs in Singapore’s Murky Waters
摘要
Coral reefs in Singapore have persisted in a sediment-rich environment due to ongoing coastal development. Discerning sediment regimes and sediment movement around the reefs is imperative in understanding how corals respond to elevated sediment load. Through a dedicated coral reef monitoring initiative conducted by the Tropical Marine Science Institute (TMSI), suspended sediment regimes are described for fringing reefs at three islands: Pulau Hantu, Kusu Island and Pulau Satumu. The results indicate that horizontal sediment flux may be influenced by the spring-neap tidal cycles of the diurnal tide. High mobility of sediments in reef environments in Singapore was observed, underscoring the importance of orientation of the reef to main flow direction on local resuspension of suspended sediments due to island wakes. Over the longer time scale, it was apparent that increases in suspended sediment were related to local coastal activity rather than transport from external sources. Reef environments in Singapore appear to be both sources and sinks of suspended sediments, depending on the different hydrodynamic conditions, which may account for the elevated suspended sediment observed around reef environments in Singapore.