Historical change of mercury pollution in remote Yongle archipelago, South China Sea

We collected three ornithogenic coral sand sedimentary profiles from Jinyin Island, Jinqing Island and Guangjin Island of Yongle archipelago, South China Sea and reconstructed the deposition flux of anthropogenic Hg over the past 700 years in the study area. On the whole, the anthropogenic Hg flux is relatively low; it remained at a low level before the Industrial Revolution with a small peak at about 1450–1550 AD, which may record the enhanced metallurgy activity in Ming Dynasty of China. During the 20th century, the deposition flux of anthropogenic Hg increased rapidly, but two troughs occurred during the periods around 1940s and 1970s, corresponding to the economic depression caused by World War II, Civil War in China (1945–1949), and the Culture Revolution (1966–1976) in China. Since the 1970s the deposition flux of anthropogenic Hg has been persistently increasing, apparently the result of fast economic development in East and Southeast Asia countries around South China Sea.

► Historical record of anthropogenic Hg flux is reconstructed in South China Sea islands.
► One small peak of prehistorical Hg flux was identified at about 1450–1550 AD.
► Post-1850 anthropogenic Hg flux increased gradually with two low value periods.
► Rapid increase of Hg flux after 1970s indicated regional migration of Hg production.
► Anthropogenic Hg flux has close relationship with the Asia economic development.