在高度动态的水文条件下,温带河流中的甲基和相关水质变量的时空变化
Eunji Jung1, Sungsook Park1, Hyunji Kim2
1School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Republic of Korea; Research Center for Innovative Energy and Carbon Optimized Synthesis for Chemicals, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea.
The Science of the total environment
|May 10, 2024
概括
河水中的甲基 (MeHg) 主要由当地生物地化学因素控制,而不是外部运输. 降雨量变化显著影响影响MeHg水平的关键水质参数.
科学领域:
- 环境化学环境化学
- 水生毒理学 水生毒理学
- 生态系统动力学 生态系统动力学
背景情况:
- 在淡水生态系统中甲基 (MeHg) 的积累日益令人担忧,特别是在气候变化方面.
- 了解影响河流MeHg时空变化的环境因素对于预测生态系统影响至关重要.
- 在动态水文条件下的河流系统中,关于MeHg动态的数据有限.
研究的目的:
- 为了调查在山河下游区域的MeHg度变化.
- 为了确定驱动MeHg时空动态的关键环境因素.
- 评估水文条件对MeHg水平的影响.
主要方法:
- 分析水质和水文数据 (1997-2022年) 和 (Hg) 和MeHg数据 (2017-2022年).
- 应用部分最小平方回归来识别有影响力的环境变量.
- 利用动态时间曲线和热图集群分析,将时间趋势与水文因素联系起来.
主要成果:
- 夏季的MeHg度 (35.7 pg L-1) 比秋季 (26.7 pg L-1) 更高.
- 溶解氧 (DO),导电性,酸盐和溶解有机碳 (DOC) 显著影响了MeHg的变化.
- 降雨变化,而不是辐射或温度,是DO,导电性,酸盐和DOC的时间趋势的主要驱动因素.
结论:
- 控制in situ Hg甲基化的生物地化学因素是MeHg空间时间变化的主要驱动因素.
- 在研究的河流区域中,Hg(II) 和MeHg的外部运输起到较小的作用.
- 这些发现凸显了当地甲基化过程在河流MeHg动态中的重要性.
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