岩石风化可以抵消永久冻土融化引起的河流二氧化碳排放
近日，北京师范大学夏星辉团队报道了岩石风化可以抵消永久冻土融化引起的河流二氧化碳排放。这一研究成果发表在2026年6月17日出版的《自然》杂志上。
气候引起的永久冻土融化释放出大量有机碳，这些有机碳经矿化后以二氧化碳（CO2）的形式从河流排放到大气中。与此同时，气候变暖和永久冻土融化可能提高矿物风化速率，从而影响无机碳的释放与封存。然而，这些生物与地质碳循环如何相互作用，并共同影响永久冻土河流中CO2的动态（排放与吸收的对比），仍属未知。
研究组结合CO2排放通量、有机和无机溶质浓度、双碳同位素（δ13C–Δ14C）及地球化学模型，来推断在数十年至数百年尺度上，永久冻土融化可能如何影响青藏高原的河流生物地球化学。利用一个热力永久冻土退化梯度，研究组发现，随着永久冻土覆盖度降低，河流CO2排放减少，而岩石风化的溶质通量则增加。
在整个研究区域，岩石风化带来的净CO2吸收通量约占河流CO2排放的35%，这一比例从连续永久冻土流域的约15%变化至不连续或岛状永久冻土流域的超过100%。因此，随着永久冻土持续融化，化学风化产生的碳通量可能变得日益重要，甚至有可能超过河流CO2排放。该研究厘清了生物与地质碳通量之间的相互作用，这对冰冻圈和全球碳循环具有重要意义。
附：英文原文
Title: Rock weathering can counteract river CO2 emissions induced by permafrost thaw
Author: Zhang, Liwei, Bufe, Aaron, Dean, Joshua F., Rocher-Ros, Gerard, Sponseller, Ryan A., Stanley, Emily H., Karlsson, Jan, Butman, David E., Liu, Ran, Hou, Lijun, Ding, Jinzhi, Piao, Shilong, Xia, Xinghui, Battin, Tom J.
Issue&Volume: 2026-06-17
Abstract: Climate-induced permafrost thaw unlocks large stores of organic carbon that are mineralized and emitted as carbon dioxide (CO2) from rivers to the atmosphere1. Concurrently, warming and permafrost thaw can increase mineral weathering rates, thus affecting the release and sequestration of inorganic carbon2,3,4. Yet how these biological and geological carbon cycles interact and jointly affect CO2 dynamics (emission compared with drawdown) in permafrost rivers remains unknown5. Here we combine CO2 emissions, organic and inorganic solute concentrations, dual carbon isotopes (δ13C–Δ14C) and geochemical modelling to infer how permafrost thaw may affect river biogeochemistry over decades to centuries across the Qinghai–Tibet Plateau. Leveraging a gradient of thermal permafrost degradation, we find that river CO2 emissions decline, whereas solute fluxes from rock weathering increase with decreasing permafrost cover. Across this region, net CO2 drawdown fluxes from rock weathering are about 35% of river CO2 emissions, varying from around 15% in catchments with continuous permafrost to more than 100% in catchments with discontinuous or isolated permafrost. Thus, carbon fluxes from chemical weathering may become increasingly important with ongoing permafrost thaw, potentially even outpacing river CO2 emissions. Our findings disentangle the interplay between biological and geological carbon fluxes that are important for the cryosphere and the global carbon cycle.
DOI: 10.1038/s41586-026-10664-8
Source: https://www.nature.com/articles/s41586-026-10664-8
期刊信息
Nature：《自然》，创刊于1869年。隶属于施普林格·自然出版集团，最新IF：69.504
官方网址：http://www.nature.com/
投稿链接：http://www.nature.com/authors/submit_manuscript.html