Sr/Ca profile of long-lived Tridacna gigas bivalves from South China Sea: A new high-resolution SST proxy

Sr/Ca differences within and among three Tridacnidae species from the South China Sea: Implication for paleoclimate reconstruction

“…Biological and geochemical parameters such as growth rate, δ 18 O and Sr/Ca ratios of Tridacnidae samples have been considered as reliable proxies for palaeo-environmental change in recent papers (Aharon et al, 1980;Aharon, 1983;Aharon and Chappell, 1986;Aharon, 1991;Watanabe and Oba, 1999;Watanabe et al, 2004;Aubert et al, 2009;Elliot et al, 2009;Batenburg et al, 2011;Sano et al, 2012;Yan et al, 2013). For example, several studies reported that the growth increments of Tridacnidae shells are seasonally governed by the SST, with larger growth increments occurring during the summer (Watanabe and Oba, 1999;Aubert et al, 2009).…”

Environmental controls on the boron and strontium isotopic composition of aragonite shell material of cultured <i>Arctica islandica</i>

“…In general, co-precipitation of Sr to Ca in aragonite decreases with temperature increases due to a declining distribution coefficient, which has been both measured and derived theoretically (Dietzel et al, 2004). The negative correlation between skeletal Sr/Ca ratios observed in some massive corals with ambient seawater temperature has been widely established and applied to reconstruct paleo-seawater temperature (Beck et al, 1992;Corrège, 2006;de Villiers, 1999;McCulloch et al, 1994McCulloch et al, , 1996Shen et al, 1996;Weber, 1973;Yan et al, 2013;Yu et al, 2005). However, these relationships may be biased by the influence from symbionts causing an apparent vital effect Cohen et al, 2002Cohen et al, , 2006Stevenson et al, 2014) or by ontogenetic age, grow rates, metabolic activity related to temperature and/or salinity (Purton et al, 1999).…”

“…This is especially important in coastal regions where freshwater input from river, surface runoff and/or groundwater mix with seawater often modifying both physical (e.g., temperature, salinity and/or turbidity) and chemical (e.g., nutrients, trace metal and/or isotopic compositions) conditions. Even for isotopic systems with long residence times in seawater (including boron), observations indicate that large fluxes of freshwater can cause substantial variations in coastal environments where conservative mixing behavior is generally assumed but not always achieved (Chung et al, 2009;D'Olivo et al, 2015;Huang and You, 2007;Huang et al, 2011;Widerlund and Andersson, 2006). Radiogenic strontium has successfully been used to trace unique water masses.…”

“…Weidman (1995) demonstrated that the geochemical signature in the shell material reflects that of the ambient water conditions and not pore water. Arctica islandica is highly suitable for environmental and ocean studies because (1) A. islandica is extremely long-lived -up to 5 centuries (Butler et al, 2013;Schöne et al, 2005;Wanamaker Jr. et al, 2008a); (2) it produces annual growth increments in its shell (Jones, 1980); (3) regional increment series can be crossdated, demonstrating a common response to environmental forcing(s) (Schöne et al, 2003); (4) fossil shells can be crossdated and floating shell chronologies can be constructed after radiocarbon dating (Scourse et al, 2006); (5) live-caught shells can be crossdated with fossil shells to assemble very long, absolutely dated growth records (Butler et al, 2009(Butler et al, , 2011Marchitto et al, 2000); (6) master shell chronologies can be created that are as statistically robust as tree ring chronologies (Butler et al, 2010); (7) it precipitates its aragonite shell in oxygen isotope equilibrium with ambient seawater (Weidman et al, 1994); and (8) the geochemical signature (e.g., 14 C, δ 18 O, δ 13 C) from shell material has been used to reconstruct ocean circulation, hydrographic changes, seasonal changes in ocean conditions, and ecosystem dynamics (Butler et al, 2009;Schöne et al, 2005Schöne et al, , 2011aScourse et al, 2012;Wanamaker Jr. et al, 2008a, b, 2009, 2011Weidman and Jones, 1993;Weidman et al, 1994;Witbaard and Bergman, 2003). Despite the potential as environmental proxies, applications of non-traditional isotopic systems (δ 11 B and δ 88 / 86 Sr) that have the capacity to reveal additional oceanographic and environmental information have not been explored fully.…”

Fluctuations of sulfate, S-bearing amino acids and magnesium in a giant clam shell

“…Long-lived bivalves such as reef-dwelling giant clams are geologically important producers of biominerals that provide long-term records (up to ∼ 100 years) of environmental conditions in tropical and subtropical oceans (e.g., Watanabe et al, 2004;Aubert et al, 2009). Previous studies have analyzed the element profiles of divalent cations and Sr / Ca ratios, the primary objective being to evaluate them as environmental proxies (e.g., Elliot et al, 2009;Sano et al, 2012;Yan et al, 2013).…”