Climate Impacts Research Centre (CIRC), Department of Ecology and Environmental Science, Umeå University, Linnaeus väg 6, 901 87, Umeå, Sweden.
Swedish Geotechnical Institute, Olaus Magnus väg 35, 581 93, Linköping, Sweden.
Nat Commun. 2021 Feb 5;12(1):825. doi: 10.1038/s41467-021-21054-1.
High-latitude regions play a key role in the carbon (C) cycle and climate system. An important question is the degree of mobilization and atmospheric release of vast soil C stocks, partly stored in permafrost, with amplified warming of these regions. A fraction of this C is exported to inland waters and emitted to the atmosphere, yet these losses are poorly constrained and seldom accounted for in assessments of high-latitude C balances. This is particularly relevant for Western Siberia, with its extensive peatland C stocks, which can be strongly sensitive to the ongoing changes in climate. Here we quantify C emission from inland waters, including the Ob' River (Arctic's largest watershed), across all permafrost zones of Western Siberia. We show that the inland water C emission is high (0.08-0.10 Pg C yr) and of major significance in the regional C cycle, largely exceeding (7-9 times) C export to the Arctic Ocean and reaching nearly half (35-50%) of the region's land C uptake. This important role of C emission from inland waters highlights the need for coupled land-water studies to understand the contemporary C cycle and its response to warming.
高纬度地区在碳 (C) 循环和气候系统中发挥着关键作用。一个重要的问题是，在这些地区变暖加剧的情况下，大量土壤碳储量（部分储存在永久冻土中）的调动和向大气中的释放程度。其中一部分 C 被输出到内陆水域并排放到大气中，但这些损失的程度很难确定，而且在评估高纬度 C 平衡时很少考虑到这些损失。对于西西伯利亚来说，这一点尤其重要，因为它拥有大量的泥炭地碳储量，而这些储量可能对正在发生的气候变化非常敏感。在这里，我们量化了包括鄂毕河流域（北极最大的流域）在内的所有西西伯利亚永久冻土带内陆水域的 C 排放。结果表明，内陆水域的 C 排放很高（0.08-0.10PgCyr），对区域 C 循环具有重要意义，在很大程度上超过了（7-9 倍）向北冰洋的 C 输出，达到了该地区陆地 C 吸收量的近一半（35-50%）。内陆水域 C 排放的这一重要作用突出表明，需要进行陆地-水域耦合研究，以了解当代 C 循环及其对变暖的响应。
