摘要
Uvigerina属底栖有孔虫的Mg/Ca-温度指标常用于古海洋底水温度的重建。然而前人研究指出,其温度重建结果可能受到碳酸盐化学等非温度因素的干扰,且种间差异对重建结果的影响也存在争议。为进一步评估该属有孔虫元素指标的可靠性,本研究基于BJ8-03航次在印度尼西亚苏拉威西边缘采集的表层沉积物,结合多种元素比值(Mg/Ca、Li/Ca、Mg/Li、B/Ca和Sr/Ca),对比U.proboscidea、U.peregrina和U.elongatastriata 3个属种的温度和碳酸盐化学指标,结合全球多个站位已发表的Uvigerina元素数据,重新审视了Uvigerina种间差异及温度重建方法。结果表明,影响Uvigerina温度指标公式的主要因素可能是种间差异而非清洗方法。在多指标对比过程中,发现U.proboscidea的Mg/Ca与温度、U.proboscidea和U.peregrina的Sr/Ca与Δ[CO_(3)^(2-)]相关性较好,而U.elongatastriata的数据较为分散,与环境参数没有相关性。此后,进一步结合全球各站位数据更新了U.peregrina的Mg/Ca-温度公式(Mg/Ca=0.94(±0.059)+0.06(±0.007)×温度),其温度敏感性(6%)与前人结果相近,说明该指标较稳定;而Mg/Li的温度敏感性与前人结果不同,因此该指标的有效性有待进一步研究。与Mg/Ca和Mg/Li不同的是,Uvigerina属的Li/Ca、B/Ca和Sr/Ca与海水温度和碳酸盐化学参数并未显示可靠的相关性,其海水环境指示意义有待进一步的验证。
The Mg/Ca ratio of benthic foraminifera Uvigerina spp.is commonly used for reconstruction of bottom water temperature(BWT).However,BWT reconstructions may be influenced by non-thermal factors such as carbonate chemistry,and the effect of interspecies difference within Uvigerina spp.remain debated.To further assess the reliability of foraminiferal elemental proxies,we use multiple elemental ratios(Mg/Ca,Li/Ca,Mg/Li,B/Ca,and Sr/Ca)of three species of Uvigerina(U.proboscidea,U.peregrina,and U.elongatastriata)from core-top sediments collected during the BJ8-03 cruise in Sulawesi,Indonesia to compare interspecies difference in BWT and carbonate chemistry proxies.By compiling published elemental data of Uvigerina from various sites in the global ocean,we re-examined the interspecies difference and BWT reconstruction methods.Results show that the main factor affecting the BWT proxies of Uvigerina was due to interspecies difference,not the cleaning method.By multi-proxy comparison,we found that Mg/Ca in U.proboscidea correlated well with BWT,and Sr/Ca in both U.proboscidea and U.peregrina correlated withΔ[CO_(3)^(2-)].In contrast,data of U.elongatastriata are scattered and showed no significant correlation with environmental parameters.Furthermore,we updated the Mg/Ca-BWT equation for U.peregrina(Mg/Ca=0.94(±0.059)+0.06(±0.007)×BWT)using compiled data from global sites.The sensitivity of Mg/Ca to BWT(6%)is similar to previous results,suggesting that the Mg/Ca proxy is robust.However,the sensitivity of Mg/Li to BWT differed from previous results,suggesting that the validity of this proxy requires further investigation.Li/Ca,B/Ca,and Sr/Ca showed no robust correlations with BWT and carbonate chemistry,and their potential of indicating seawater environmental parameters needs further evaluation.
作者
周晓理
杨淳渝
ZHOU Xiaoli;YANG Chunyu(State Key Laboratory of Marine Geology,Tongji University,Shanghai 200092,China)
出处
《海洋地质与第四纪地质》
北大核心
2025年第4期60-72,共13页
Marine Geology & Quaternary Geology
基金
国家重点研发计划“利用冷水珊瑚重建南海深部物质能量循环(青年项目)”(2021YFF0502500)
国家自然科学基金“中中新世太平洋深部海水性质与洋流变迁的全球影响”(42006053)
上海市科委基础研究特区计划“多尺度智能化的海洋气候演变研究”(22TQ1400300)。
作者简介
周晓理(1989-),女,博士,副教授,从事古海洋和古气候学研究,E-mail:xlzhou@tongji.edu.cn。
