Distribution and origination of heavy metal pollution in bays of northern Hainan Island

Hainan Island has been developing rapidly in recent years. Accompanied with the development of social economy, various degrees of heavy metal pollution has become an issue of pollution to the sea areas around the Hainan Island especially in the bays to the north of the island. To better understand the heavy metal pollution at present in those bays, surface sediments were sampled in Puqian Bay, Chengmai Bay, Houshui Bay, and Yangpu Bay in 2019. According to the China’s national standard on marine sediment quality （GB18668—2002）, using multiple parameters including the index of geo-accumulation （I_geo）, contamination factor （C_f）, the degree of contamination （C_d）, and ecological risk factor （E_r）, the heavy metal pollution status in different those bays were evaluated. Results show that arsenic （As） was the common heavy metal pollutant among the bays. The pollution status in Chengmai Bay and Puqian Bay were relatively more serious than in Yangpu Bay. Anthropogenic activities such as fuel combustion by marine vessels, fertilizer application, and waste water discharge from mining could cause different levels of heavy metal pollution. Countermeasures shall be taken for the environmental protection by the local managements to prevent and control heavy metal pollution in the bays to the north of Hainan Island.