High-resolution Mg/Ca ratios in a coralline red alga as a proxy for Bering Sea temperature variations from 1902 to 1967
High-resolution Mg/Ca ratios in a coralline red alga as a proxy for Bering Sea temperature variations from 1902 to 1967
复制标题
珊瑚红藻中的高分辨率 Mg/Ca 比率作为 1902 年至 1967 年白令海温度变化的代理
DOI：
10.2110/palo.2008.p08-116r
复制
发表时间：
2009
影响因子：
3.6
通讯作者：
B. Schöne
中科院分区：
文献类型：
--
作者：
S. Hetzinger;J. Halfar;A. Kronz;R. Steneck;W. Adey;P. Lebednik;B. Schöne
摘要我们首次连续记录了阿留申群岛Amchitka岛的一种红壳珊瑚Clathromorphum nereostratum的Mg/Ca变化。通过测量单点电子微探针样带分析了个体生长增量的Mg/Ca比，得到的分辨率为1015个样本/年和65年（1902-1967）的变化记录。结果表明，高镁方解石藻类骨架中的Mg/Ca比值具有明显的年周期性，并与藻类生长的主要季节春末秋末的海表温度（SST）相对应。Mg/Ca值与当地SST以及同一地区的气温记录相关。在亚北极北太平洋的大尺度SST变化的高空间相关性，观察到的模式的最强的相关性的主要海洋学功能，发挥了关键作用，在北太平洋和白令海之间的水团交换的方向。我们的数据与第二个站点的较短Mg/Ca记录相关性很好，证实了该仪器可靠记录区域环境信号的能力。此外，Mg/Ca比与在同一样本上测量的29年δ 18 O时间序列具有良好的相关性，为珊瑚红藻中的Mg用作古温度替代物提供了额外的支持，与藻类-δ 18 O不同，它不受影响。盐度波动。此外，基于电子探针的分析可以实现更高的采样分辨率和更快的分析，从而为未来更长的C的研究提供了有希望的方法。nereostratum记录和应用于其他珊瑚物种。
Abstract We present the first continuous, high-resolution record of Mg/Ca variations within an encrusting coralline red alga, Clathromorphum nereostratum, from Amchitka Island, Aleutian Islands. Mg/Ca ratios of individual growth increments were analyzed by measuring a single-point, electron-microprobe transect, yielding a resolution of ∼15 samples/year and a 65-year record (1902–1967) of variations. Results show that Mg/Ca ratios in the high-Mg calcite algal framework display pronounced annual cyclicity and archive late spring–late fall sea-surface temperatures (SST) corresponding to the main season of algal growth. Mg/Ca values correlate well to local SST, as well as to an air temperature record from the same region. High spatial correlation to large-scale SST variability in the subarctic North Pacific is observed, with patterns of strongest correlation following the direction of major oceanographic features that play a key role in the exchange of water masses between the North Pacific and the Bering Sea. Our data correlate well with a shorter Mg/Ca record from a second site, corroborating the ability of the alga to reliably record regional environmental signals. In addition, Mg/Ca ratios relate well to a 29-year δ18O time series measured on the same sample, providing additional support for the use of Mg in coralline red algae as a paleotemperature proxy that, unlike algal-δ18O, is not influenced by salinity fluctuations. Moreover, electron microprobe–based analysis enables higher sampling resolution and faster analysis, thus providing a promising approach for future studies of longer C. nereostratum records and applications to other coralline species.