从大陆到大海,贝的微量元素变化:圣劳伦斯系统,加拿大
Alice Guillot1, Jean-Alix Barrat2, Frédéric Olivier3
1Univ Brest, CNRS, Ifremer, IRD, LEMAR, Institut Universitaire Européen de la Mer (IUEM), Place Nicolas Copernic, 29280 Plouzané, France; Institut des Sciences de la Mer de Rimouski, Université du Québec à Rimouski, 310 Allée des Ursulines, Rimouski, QC G5L 3A1, Canada.
Marine pollution bulletin
|January 18, 2024
概括
贝的贝揭示了圣劳伦斯河和河口的淡水和盐水环境之间的独特化学特征. 微量元素分析突出了稀土元素和的差异,表明了环境变化.
科学领域:
- 环境科学 环境科学
- 地质化学 地质化学
- 海洋生物学 海洋生物学
背景情况:
- 贝的贝作为地质化学和环境研究的宝贵档案.
- 贝中的微量元素和稀土元素 (REE) 和 (REY) 组成反映了环境水的化学成分.
- 圣劳伦斯河,河口和海湾 (EGSL) 呈现出一种独特的环境,具有淡水和海洋的影响.
研究的目的:
- 研究圣劳伦斯河和EGSL的贝中REY和微量元素的分布和变异.
- 为了区分淡水和海洋双贝的化学成分.
- 在研究区域评估潜在的污染指标,如加多 (Gd) 和 (Pb).
主要方法:
- 来自圣劳伦斯河,河口和海湾沿线的各种地点的贝收藏.
- 使用已建立的地化学技术分析稀土元素和 (REY) 丰度.
- 微量元素的测量包括 (Mn), (Ba), (Sr),加多 (Gd) 和 (Pb).
- 页岩规范化REY数据与全球标准 (PAAS) 的比较.
主要成果:
- 在淡水和海水贝之间观察到明显的化学模式.
- 淡水贝呈现出更平坦的REY图案,度更高的Mn和Ba.
- 海水含有更丰富的Sr,并显示了页岩正常化的REY模式,具有正的La和Y异常和负的Ce异常,反映了海水的特征.
- 在圣劳伦斯河或EGSL中没有发现可检测的Gd污染.
- 在Saguenay Fjord口或Rimouski附近没有观察到可检测的Pb污染.
结论:
- 贝的地质化学有效地区分了圣劳伦斯系统内的淡水和海洋环境.
- 在海洋贝中观察到的REY异常与海水成分一致.
- 该研究证实,在圣劳伦斯河和EGSL的调查区域中,没有显著的Gd和Pb污染.
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