Lacustrine Ostracodes as Environmental Change Indicators: Application and Advance
Lacustrine Ostracodes as Environmental Change Indicators: Application and Advance
复制标题
DOI：
10.18307/20010413
复制
发表时间：
2001
期刊：
影响因子：
--
通讯作者：
Li Jun;Yu Junqing
中科院分区：
文献类型：
--
作者：
Li Jun;Yu Junqing
Ostracodes, the microscopic bivalved crustaceans, survive in a wide diversity of lakes and ostracod fossil valves are often found well preserved in the lake sediment sequences. The characteristics of ostracod palaeoecology and particularly geochemical characteristics of fossil ostracod shells buried in the lake sediment sequences are increasingly studied and used to indicate the past environmental changes on the globe. The isotopic composition and temperature of the lake water in which the shells formed determine the oxygen isotopic composition of shells. Changes in δ 18 O ostracod in a sediment sequence may reflect the past variations of δ 18 O water relating to climate induced changes in precipitation to evaporation balance. In general, low δ 18 O ostracod may reflect warm or moist climate, while high δ 18 O ostracod may represent cold or dry climate. The δ 13 C ostracod may reflect the isotopic ratios of total dissolved inorganic carbon (TDIC) and the changes of factors controlling δ 13 C TDIC value, especially palaeoproductivity of a lake. The uptake of Mg and Sr into ostracod shells may be a function of salinity and temperature of host water, which can be used to reconstruct palaeosalinity and palaeotemperature of a lake. The following aspects are required in order to conduct quantitative research: (1) firm understanding of the life history and ecological procedure of the ostracod species concerned, (2) analyzing field regular collections of ostracod shells and lake waters, to learn the controls of the water chemistry and temperature on the composition of stable isotopes and trace elements of ostracod shells, (3) detailed knowledge of the limnology of the lake investigated, including the relationship between M/Ca and salinity, the isotopic composition and the spatial and seasonal variations in these properties, and (4) culture experiments for each species used, to establish the effects of physiology on the trace elements uptake and determine the isotopic behavior of indivdual ostracod species with host water.
