High riverine CO2 emissions at the permafrost boundary of Western Siberia
High riverine CO2 emissions at the permafrost boundary of Western Siberia
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DOI：
10.1038/s41561-018-0218-1
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发表时间：
2018-09
影响因子：
18.3
通讯作者：
S. Serikova;O. Pokrovsky;P. Ala‐aho;V. Kazantsev;S. Kirpotin;S. Kopysov;I. Krickov;H. Laudon
中科院分区：
文献类型：
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作者：
S. Serikova;O. Pokrovsky;P. Ala‐aho;V. Kazantsev;S. Kirpotin;S. Kopysov;I. Krickov;H. Laudon
世界上最大的泥炭地西西伯利亚低地的永久冻土中储存的大量有机碳的命运尚不确定。具体而言，该地区河流的温室气体排放量尚不清楚。在此，我们对西西伯利亚低地所有永久冻土区（北纬 56° 至 67° ）的 58 条河流的年二氧化碳排放量进行了估算。我们发现，排放量在永久冻土边界处达到峰值，而在永久冻土更普遍和气候条件较冷的地方则排放量减少。河流二氧化碳排放量很高，平均是下游碳排放量的两倍。我们认为，高排放量和排放/出口比是气温升高和河水过境时间长的结果。我们表明，西西伯利亚低地的河流通过在陆地碳输送到北冰洋之前对其进行脱气，在碳循环中发挥着重要作用，并表明温度和降水的变化对于理解和预测气候变化中高纬度河流的二氧化碳排放非常重要。
The fate of the vast stocks of organic carbon stored in permafrost of the Western Siberian Lowland, the world’s largest peatland, is uncertain. Specifically, the amount of greenhouse gas emissions from rivers in the region is unknown. Here we present estimates of annual CO2emissions from 58 rivers across all permafrost zones of the Western Siberian Lowland, between 56 and 67° N. We find that emissions peak at the permafrost boundary, and decrease where permafrost is more prevalent and in colder climatic conditions. River CO2emissions were high, and on average two times greater than downstream carbon export. We suggest that high emissions and emission/export ratios are a result of warm temperatures and the long transit times of river water. We show that rivers in the Western Siberian Lowland play an important role in the carbon cycle by degassing terrestrial carbon before its transport to the Arctic Ocean, and suggest that changes in both temperature and precipitation are important for understanding and predicting high-latitude river CO2emissions in a changing climate.