(1)Nanjing Institute of Geography & Limnology, Chinese Academy of Sciences, Nanjing 210008 ,China;
(2)Geology Institute, Tokyo University, Tokyo 113, Japan ,China
Abstract:
Ostracods are small bivalved aquatic crustaceans. They secrete shells of low-Mg calcite that are often preserved in lake sediments. Recent work has shown that the uptake of trace elements (especially Mg and Sr) into the shell may be a function of the salinity and temperature of the host water. We measured Sr/Ca ratios in living ostracod valves from the species of genus Limnocythere cf. inopinata and Sr2+/Ca2+ ratios of the host water to calculate distribution coefficient of genus Limnocythere cf. inopinata in the Daihai Lake. A function for Sr2+/Ca2+ ratio and salinity was established by measuring a series of Sr2+/Ca2+ ratios and salinities of the lake water in different places of the Daihai Lake. Finally paleosalinities of the lake water were quantitatively reconstructed by the Sr/Ca ratios of ostracod shells of the same species in sediment core of the Daihai Lake.