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低估的干河床:在将间歇性河流CO2排放等同于多年河流的关键因素

Chao Qin¹, Yuan Xue¹, Mengzhen Xu¹

¹State Key Laboratory of Hydroscience and Engineering, Tsinghua University, Beijing 100084, China.

|June 8, 2024

概括

间歇性河流对碳循环产生重大影响,但它们的二氧化碳排放往往被低估. 这项研究量化了水和干河床的排放量,揭示了它们在全球碳评估中的关键作用.

科学领域:

环境科学环境科学
水文学的水文学
地质化学地质化学

背景情况:

在干旱/半干旱地区普遍存在的间歇性河流是全球碳循环的关键,但量化不足的组成部分.
现有的碳循环评估是不准确的,因为低估了流量持续时间,河流表面积和干燥河床的二氧化碳排放.

研究的目的:

准确估计和提取黄河的一个关键支流 - - 黄福川的流量持续时间,河水表面积和干河床面积.
在间歇性河流系统中,量化来自水空气界面和干燥河床的二氧化碳 (CO2) 排放量.
提出一种标准化的方法来估计数据稀缺的间歇性河流,特别是山区的二氧化碳排放.

主要方法:

利用高分辨率遥感图像进行空间数据提取.
综合密集的现场测量用于现场数据收集 (二氧化碳排放率,部分压力).
采用水文建模来估计流量持续时间,河流表面积和河床干燥面积.

主要成果:

2018年,黄福川河的流量持续时间从支流的不到5天到主流的150天不等.
河流水面积在不同的排放频率中从3.9到88.6平方公里不等.
估计每年二氧化碳排放总量为937.5×103,干燥的河床有很大贡献 (355.2×103).

结论:

干燥的河床在间歇性河流系统的碳循环中起着重要的,但经常被忽视的作用.
拟议的方法提供了一个标准化和适用的解决方案,用于数据稀缺的间歇性河流中的二氧化碳排放估计.
准确量化间歇性河流动态对于完善全球碳循环模型至关重要.

关键词:

的二氧化碳排放量.流量持续时间流量持续时间间歇性河流是间歇性的河流.山地河流是一个山地河流.提取河流表面的提取方法

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