采样频率,负载估计和风暴对河流中溶液质量流的不成比例影响
Jinyu Wang1, Julien Bouchez2, Antoine Dolant3
1University of Illinois at Urbana-Champaign, Department of Earth Science and Environmental Change, Urbana, IL, USA.
The Science of the total environment
|September 30, 2023
概括
高频河流监测显示,风暴事件显著影响溶液出口. 粗采样低估了营养流量,高估了其他溶液,影响了水质和土地管理.
科学领域:
- 环境化学环境化学
- 水文学的水文学
- 地质化学 地质化学
背景情况:
- 河流溶解物质质量出口量由排放 (Q) 和溶解度 (C) 确定.
- 高频Q数据是常见的,但稀疏的C数据需要负载估计算法.
- 由于数据限制,短期事件对溶液流量的影响尚不清楚.
研究的目的:
- 将高时间分辨率主要离子化学数据与常见负载估计算法进行比较.
- 量化由于减少采样频率而导致的溶液负载估计中的错误.
- 评估风暴事件对不同流域大小的溶解物质质量流的影响.
主要方法:
- 使用了用于持续监测的新型"实验室实地"仪器仪表.
- 收集了一年多的高分辨率 (∼30分钟至7小时) 大离子化学数据.
- 分析了来自三个流域的数据,涵盖排水面积的四个数量级.
主要成果:
- 粗化采样频率系统地高估了稀释溶液 (例如Na+,Cl-) 和低估了调动营养素 (例如K+,NO3-).
- 错误在较大的河流中最为明显,与错过的风暴事件和减少采样有关.
- 每月采样导致Na+的高估值为8%,K+的低估值为32.5%.
结论:
- 高频监测对于准确评估溶解物质质量出口至关重要,特别是在风暴期间.
- 使用稀疏数据的当前负载估计方法可能导致环境评估中的重大偏差.
- 这些发现对沿海缩,气候预算和农业管理有影响.
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