河流水库系统中的酸盐来源和转变:应对极端洪水和各种土地利用
Xingchen Zhao1,2, Hai Xu1, Lijuan Kang1
1Key Laboratory of Lake and Watershed Science for Water Security, Nanjing Institute of Geography & Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing 210008, China.
Journal of hydrology
|November 28, 2025
概括
极端洪水显著增加了中国新安河和道湖的酸盐污染. 土壤侵蚀和肥料主导着河流污染,而污水对水库产生影响,凸显了流域管理的必要性.
科学领域:
- 环境科学 环境科学
- 水文学的水文学
- 水质管理水质管理
背景情况:
- 酸盐 (NO3-) 污染是一个关键的全球问题,推动了肥胖化,对水生生态系统和人类健康构成风险.
- 在复杂的流域中量化酸盐来源,特别是在洪水等极端事件期间,仍然是一个重大的科学挑战.
- 2020年中国东南地区的严重洪水导致江湖水位创新高,需要对酸盐动态进行调查.
研究的目的:
- 调查酸盐 (NO3-) 的来源和在新安河 - 湖系统中的变化.
- 评估灾难性2020年夏季洪水事件对酸盐污染的具体影响.
- 了解土地利用模式对酸盐分布和同位素特征的影响.
主要方法:
- 在新安河沿线和安湖内进行了广泛的水样采集.
- 酸盐度分析和稳定同位素分析 (δ15N-NO3-).
- 贝叶斯模型用于识别和量化酸盐来源.
主要成果:
- 观察到明显的度梯度,从原始的头水增加到受人类影响的农业和住宅区.
- 同位素分析显示,在河流的洪水季节,土壤侵蚀和化学肥料 (74%) 的贡献很大.
- 污水排放和溢出大大影响了江湖 (53%的输入),特别是在城市地区,在洪水和基流条件下有明显的来源贡献.
结论:
- 极端洪水事件极大地改变了河流水库系统中的酸盐来源和运输动态.
- 土地利用是影响酸盐水平和同位素特征的关键因素,农业和城市地区是主要热点.
- 有效的流域管理策略对于减轻酸盐污染至关重要,应对点源和非点源,特别是在高流量事件期间.
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