尺寸问题:在浅层热石岩湖的沉积物中氧化甲氧化
Rinat Manasypov1,2, Lichao Fan1, Artem G Lim2
1College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi, China.
Global change biology
|January 26, 2024
概括
浅层热岩湖释放温室气体 (GHG) 作为永久土的融化. 由于混合的增加,较大的湖泊表现出更高的甲氧化,而较小的湖泊产生更多的二氧化碳.
科学领域:
- 环境科学 环境科学
- 地质化学 地质化学
- 气候科学 气候科学
背景情况:
- 浅层热岩湖是温室气体 (GHG) 的重要来源,包括甲 (CH4) 和二氧化碳 (CO2),这是由于全球变暖而导致的永久土融化所致.
- 湖泊水中的温室气体度通常随着湖泊大小的减少而上升,这归因于海岸侵蚀和有机物流入.
研究的目的:
- 为了研究湖泊大小对甲 (CH4) 氧化和二氧化碳 (CO2) 生产在浅层热湖沉积物的影响.
- 为了测试CH4氧化随着氧化增加而增加湖泊大小的假设,CO2产量随着湖泊大小的减少而增加,这两种过程在上层沉积层中都更为显著.
主要方法:
- 使用13C标记的CH4.4估计有氧CH4氧化潜力和CO2产量.
- 在西西伯利亚低地小,中,大浅热岩湖的0-10厘米和10-20厘米深度的沉积物核心中进行的实验.
主要成果:
- 在上层沉积物中,二氧化碳的产量是上层沉积物的1.43.5倍,从大湖增加到小湖.
- 沉积物深度的甲氧化率在大湖中显著高 (14-至74倍),相比于中小湖,这是由于风引起的混合使得氧气可用性更大.
- 上层沉积物中的CH4氧化在所有湖泊大小中都是相似的.
结论:
- 湖泊的大小是影响热湖温室气体循环的关键因素,较小的湖泊表现出更高的二氧化碳产量,较大的湖泊显示出增强的CH4氧化.
- 这些发现证实热岩湖是全球温室气体排放的重要热点,排放动态严重依赖湖泊形态和相关的物理过程,如风引起的混合.
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