基于贝叶斯混合模型对沉积物核心中的有机物质的人为影响:Daya Bay的一个案例研究
Xiangtian Man1,2, Honghui Huang3,4, Shijun Jiang5
1Institute for Environmental and Climate Research, Jinan University, Guangzhou, 511443, China.
Environmental science and pollution research international
|October 2, 2023
概括
戴亚湾的沉积物核心揭示了70年来有机物质来源的变化. 陆地有机物输入增加,而海洋来源减少,影响了核电海洋.
科学领域:
- 环境科学 环境科学
- 海洋地球化学 海洋地球化学
- 古海洋学是古海洋学.
背景情况:
- 沉积物核心是过去环境变化的重要档案,从各种来源积累有机物质.
- 了解海洋沉积物中的有机物质的起源和演变对于评估生态系统健康和人类影响至关重要.
研究的目的:
- 在过去的70年里,分析Daya Bay沉积物核心中有机物代理物 (TOC,TN,稳定同位素) 的垂直趋势.
- 用贝叶斯混合模型确定不同有机物来源的分布特征和贡献比率.
- 调查环境变化的影响,包括核电站建设和工业扩张,对达雅湾的沉积环境.
主要方法:
- 对沉积物核心建立了沉积物时间表.
- 分析颗粒大小分布,总有机碳 (TOC),总 (TN) 和稳定同位素 (δ13C, δ15N).
- 应用贝叶斯混合模型 (MixSIAR) 来量化有机物源贡献.
主要成果:
- TOC,TN,δ13C和δ15N值在沉积物核心中表现出不同的范围.
- 有机物质的组成受到陆地和海洋本土来源的混合影响.
- 从1960年到2000年,观察到陆地有机物贡献增加和海洋有机物贡献减少的趋势,海洋来源仍然占主导地位.
结论:
- 与农业活动相关的初级生产率增加,首次观察到于1960年左右.
- 20世纪80年代后,戴亚湾的环境变化受到人口增长,核电站建设,水产养殖和工业扩张的重大影响.
- 沉积有机物记录提供了关于塑造海洋生态系统的自然和人为因素的复杂相互作用的见解.
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