Influence of local industrial changes on reef coral calcification.

Coral reefs are currently facing multiple disturbances caused by natural/anthropogenic factors. Recent industrial development might influence reef environments and ecosystems; however, few direct comparisons of coral calcification with the histories of local industries exist. We show the coral Ba/Ca record and growth histories for 46 years collected from Sumiyo Bay, Amami-Oshima Island, Japan. Coral Ba/Ca was mainly controlled by the sediment loads in seawater, which are introduced through the two local rivers. Coral Ba/Ca records have been characterized by two distinct historical periods: the decadal fluctuation corresponding to the traditional silk fabric industry (1960s ~ 1995) and the increasing trend corresponding to the development of quarries and the construction industry (1996 ~). Coral Ba/Ca records and local industrial histories were also linked to coral calcification. A long-term quantitative assessment of reef environments and local industrial changes could provide an evaluation of the survival strategies of reef-building corals in the future.