Opal (Zn/Si) ratios as a nearshore geochemical proxy in coastal Antarctica
Opal (Zn/Si) ratios as a nearshore geochemical proxy in coastal Antarctica
复制标题
蛋白石 (Zn/Si) 比率作为南极洲沿海近岸地球化学指标
DOI：
10.1029/2007pa001576
复制
发表时间：
2008
期刊：
影响因子：
--
通讯作者：
R. Rickaby
中科院分区：
文献类型：
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作者：
K. Hendry;R. Rickaby
在过去 50 年中，南极半岛经历了快速变暖，87% 的海洋和潮水冰川前缘随之退缩。冰川退缩和冰山崩解的加速可能会对高产沿海地区浮游植物群落的淡水和养分供应产生重大影响。然而，南极洲沿海沉积物中并未保留常用的生物碳酸盐营养物和盐度条件替代指标。在这里，我们描述了一种测量硅藻蛋白石（(Zn/Si)蛋白石）中锌硅比例的方法，硅藻蛋白石是南极海洋沉积物中的潜在档案。来自西南极半岛的岩心顶部校准显示（Zn/Si）蛋白石是混合层盐度的代表。我们提供了取自西南极半岛近岸环境的两个快速积累地点的下核 (Zn/Si) 蛋白石古盐度记录，这些记录显示近几十年来融水输入量有所增加。我们的记录显示，该地区最近的融化是 120 多年来前所未有的。
During the last 50 years, the Antarctic Peninsula has experienced rapid warming with associated retreat of 87% of marine and tidewater glacier fronts. Accelerated glacial retreat and iceberg calving may have a significant impact on the freshwater and nutrient supply to the phytoplankton communities of the highly productive coastal regions. However, commonly used biogenic carbonate proxies for nutrient and salinity conditions are not preserved in sediments from coastal Antarctica. Here we describe a method for the measurement of zinc to silicon ratios in diatom opal, (Zn/Si)opal, which is a potential archive in Antarctic marine sediments. A core top calibration from the West Antarctic Peninsula shows (Zn/Si)opal is a proxy for mixed layer salinity. We present down-core (Zn/Si)opal paleosalinity records from two rapidly accumulating sites taken from nearshore environments off the West Antarctic Peninsula which show an increase in meltwater input in recent decades. Our records show that the recent melting in this region is unprecedented for over 120 years.