在沿海河流中降雨事件期间的动态N运输和N2O排放
Wen-Xi Zhang1, Fu-Jun Yue2, Yong Wang3
1Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China.
The Science of the total environment
|August 11, 2023
概括
与低强度事件相比,沿海河流中的高强度降雨事件显著增加了氧化 (N2O) 排放. 了解这些动态对于管理受影响水生生态系统中的污染和N2O释放至关重要.
科学领域:
- 环境科学 环境科学
- 生物地质化学生物地质化学
- 水文学的水文学
背景情况:
- 沿海地区面临着高度的人为影响,导致水文条件较弱.
- 降雨事件大大改变了水流不良的河流中的营养物质运输.
- 对于气循环和N2O排放对这些河流中不同降雨类型的反应的了解很少.
研究的目的:
- 在不同的降雨事件中调查水文和气特性.
- 分析不同降雨强度下的氧化 (N2O) 排放动态.
- 了解降雨对微弱水力动态河流中气运输和N2O生物地质化学的影响.
主要方法:
- 在两个对比的降雨事件中高频率取水样:高强度/短持续 (E1) 和低强度/长持续 (E2).
- 监测水文参数,度 (TN,NO3-N) 和N2O动态.
- 分析d-超值值以描述水文条件.
主要成果:
- 高强度降雨 (E1) 引发了更动态的水文条件和明显更高的N2O度 (0.01-3.33 μmol/L),而不是低强度降雨 (E2; 0.03-1.11 μmol/L).
- 与E2.2相比,E1期间的度 (TN,NO3--N) 在E1期间较低.
- 在水和成分中观察到歇斯底里作用,表明恢复时间延长. 降雨期间的平均N2O流量 (78.3 μmol/m2/h) 明显高于没有降雨期间 (1.63 μmol/m2/h).
结论:
- 高强度降雨事件在具有弱水力动力学的沿海河流中增加N2O排放的风险更大.
- 降雨事件,特别是高强度的降雨事件,显著增加N2O排放,这是必须在年度N2O预算中考虑的因素.
- 堤调节和由此产生的水位波动可以通过增强的湿干交替加剧N2O排放.
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