近日，加拿大卡尔顿大学Elliott K. Skierszkan团队报道了永久冻土带退化引起的河流突然酸化和金属迁移。2026年5月21日出版的《科学》杂志发表了这项成果。

在北美最大的两条亚北极/北极河流——育空河与麦肯齐河流域的永久冻土覆盖的源头集水区，硫化物矿物氧化的突然加速正在改变溪流化学特性与生态系统功能。过去十年间，这些源头区域出现了数十处酸性（pH约3）渗流点，导致植被枯死，并使受纳溪流中的金属浓度达到剧毒水平。

硫化物矿物氧化过程中产生的酸，还通过驱动碳酸盐矿物溶解，加速了二氧化碳的排放。下游的亚北极/北极河流显示，硫酸盐浓度在数十年间呈现统计上显著的增加趋势，但由于衰减和稀释过程，其金属浓度保持稳定。源头溪流的酸化信号表明，与永久冻土融化相关的金属、碳和硫循环正发生重大扰动，这对水资源、北方社区、生态系统健康以及地球的生物地球化学未来将产生深远影响。

附：英文原文

Title: Abrupt stream acidification and metal mobilization from permafrost degradation

Author: Elliott K. Skierszkan, Andras J. Szeitz, Matthew B.J. Lindsay, Sean K. Carey

Issue&Volume: 2026-05-21

Abstract: Stream chemistry and ecosystem function are being transformed by abrupt acceleration of sulfide-mineral oxidation in permafrost-underlain headwater catchments of the Yukon and Mackenzie river basins—the two largest (sub)Arctic rivers in North America. Over the past decade, dozens of acidic (pH ~3) seepages have emerged in these headwaters, causing vegetation dieback and mobilizing metals at acutely toxic concentrations in receiving streams. Acid generated during sulfide-mineral oxidation also accelerates carbon dioxide emissions by driving carbonate-mineral dissolution. Downstream (sub)Arctic rivers show statistically significant multidecadal increases in sulfate concentrations, yet their metal concentrations remain stable because of attenuation and dilution processes. Headwater stream acidification signals a major perturbation in metal, carbon, and sulfur cycling linked to permafrost thaw with far-reaching consequences for water resources, northern communities, ecosystem health, and Earth’s biogeochemical future.

DOI: aea2898

Source: https://www.science.org/doi/10.1126/science.aea2898