Relationship between Water Quality Factors and Coral Growth in Dazhou Island

WANG Zhangyi; SHI Yanfei; SONG Yingying; LUO Ying; YIN Anqi; LI Hongwu

Abstract：The project of coral reef protection in Dazhou Island waters, Wanning, Hainan Province, was conducted to investigate the relationship between coral growth rate and water quality.Through regular monitoring of water quality factors and coral growth at different sites of the island to explore the environmental factors suitable for the growth of coral.The study provided a theoretical basis for the wild coral reproduction and the ecological restoration of coral reefs.Corals growth rate is connected to the water quality.We monitored the length growth rate of Acroporaformosa and the area growth rate of A.hyacinthu.The average monthly growth rate of A.formosafrom from February to May were4.45％, 5.68％, 6.94％and 10.59％, respectively.In contrast, A, hyacinthu had a greater initial area, and developed faster.Both species showed the exponential growth.From February to May, their average monthly growth rates were 10.09％, 13.82％, 11.06％and 20.92％, respectively.Coral growth rate was positively correlated with water temperature and negatively correlated with water quality factors such as COD, DIN, DIP and SS, and had no obvious correlation with DO concentration.A comparison of coral rate in four different seas showed that domestic waste and sewage generated by human activities and the breakdown of ships have a serious impact on coral growth.