Limited Carbon Cycle Response to Increased Sulfide Weathering Due to Oxygen Feedback
Limited Carbon Cycle Response to Increased Sulfide Weathering Due to Oxygen Feedback
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DOI：
10.1029/2021gl094589
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发表时间：
2021-09
影响因子：
5.2
通讯作者：
P. Maffre;N. Swanson‐Hysell;Y. Goddéris
中科院分区：
文献类型：
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作者：
P. Maffre;N. Swanson‐Hysell;Y. Goddéris
含硫化物岩石的化学风化可能导致碳酸盐岩的溶解，从而导致二氧化碳向大气中排出。虽然这一过程被认为是二氧化碳的重要地质来源，但它也扰乱了氧和硫的地质循环，引发了一连串的地球化学反馈。利用地球化学循环和气候的数值模型，我们发现，由于与有机碳循环相关的大气氧气的反馈，硫化物风化作用的增加导致二氧化碳来源有限，随后二氧化碳汇更长。这一结果是由于硫化物风化的化学计量比，其中消耗的O2比释放的CO2更多。如果硫化物风化作用在地质时间尺度上逐渐增加，碳源的持续时间会延长，但在成为碳汇之前，其大小可以忽略不计。
The chemical weathering of sulfide‐bearing rocks can result in the dissolution of carbonate rocks leading to degassing of CO2 to the atmosphere. While this process has been argued to be a significant geologic source of CO2 , it also perturbs the geological cycles of oxygen and sulfur, triggering a cascade of geochemical feedbacks. Using a numerical model of geochemical cycles and climate, we found that due to feedbacks on atmospheric oxygen associated with the organic carbon cycle, an increase of sulfide weathering leads to a limited source of CO2 followed by a longer sink of CO2 . This result is due to the stoichiometry of sulfide weathering where more O2 is consumed than CO2 is released. If sulfide weathering increases progressively on a geological timescale, the duration of the carbon source is extended, but its magnitude is negligible before it becomes a carbon sink.