Potential environment effect on ultrahigh resolution Sr/Ca of giant clam shells from South China Sea
摘要
The hourly to monthly resolution Sr/Ca profiles of modern juvenile giant clam (Tridacna spp.) shells from the northern South China Sea were obtained using ICP-OES, LA-ICP-MS and NanoSIMS. The results showed the variability of Sr/Ca profiles determined by different analytical methods were consistent on monthly time scale. The hourly resolved Sr/Ca determined by NanoSIMS showed pronounced daily cycles which may be associated with the diurnal cycle of the physiology, environment and/or weather condition. By comparison of daily resolution Sr/Ca and contemporaneous instrumental environment data, no robust link was observed between environmental parameters and juvenile Tridacna Sr/Ca, and only weak correlation was found between daily outgoing longwave radiation (OLR) (r = − 0.167, p < 0.01) and Sr/Ca. However, the effective solar radiation cannot explain the variability of nightly Sr/Ca, and some other factors are more likely to influence the Sr/Ca of juvenile Tridacna. Moreover, no consistent correlation was observed between Sr/Ca and growth rate of Tridacna. The mechanism of juvenile Tridacna Sr/Ca is still mysterious, conducting artificial culture experiments seems the best way to unravel the mechanisms behind Sr2+ incorporation into Tridacna shells.