作者：Mattio, D., Guedron, S., Sabatier, P. et al.

Mercury (Hg) atmospheric emissions in Europe peaked in the mid-20th century and have since declined due to environmental policies, reducing atmospheric deposition to ecosystems. However, regional disparities have emerged as climate change can remobilize Hg reservoirs, complicating efforts to assess environmental recovery. This study investigates Hg accumulation rates in lacustrine sediments from two neighboring high-altitude alpine lakes in the French Alps: Grand Lake (GDL), a rain-fed lake reflecting regional atmospheric deposition, and Eychauda Lake (EYC), a proglacial lake supplied by glacial meltwater and derived sediment. Sediment chronologies for both lakes were established using short-lived radionuclides, allowing for the reconstruction of Hg deposition over the past century. Comparison of the Hg records from both lakes revealed contrasting trends: GDL responds to regional anthropogenic emissions, while EYC shows a still increasing Hg accumulation rate over recent decades. This discrepancy and its correlation with erosion proxies suggest that glacier melting has released Hg stored in the ice, masking the expected trend of reduced regional emissions. These findings illustrate the importance of accounting for climate-mediated remobilization of Hg when evaluating the effectiveness of environmental policies as this process can impose a climate change-driven penalty that delays ecosystem recovery.

欧洲大气汞（Hg）排放在20世纪中叶达到峰值，此后在环境政策的推动下持续下降，生态系统的大气汞沉降随之减少。然而，区域间的差异正在显现——气候变化可使已封存的汞储库重新活化，这使环境恢复效应的评估更加复杂。研究调查了法国阿尔卑斯山两个相邻高海拔高山湖泊湖相沉积物中的汞累积速率：大湖（Grand Lake, GDL）为降雨补给湖泊，反映区域性大气沉降；艾绍达湖（Eychauda Lake, EYC）为冰前湖，由冰川融水及其搬运的冰川侵蚀沉积物补给。两湖均利用短寿命放射性核素建立了沉积物年代序列，从而重建了 past century 以来的汞沉降历史。两湖汞记录的对比呈现出截然相反的趋势：GDL响应于区域性人为排放（先升后降），而EYC近几十年的汞累积速率却仍在持续上升。这一差异及其与侵蚀替代指标的关联表明，冰川消融已释放出封存于冰体中的汞，掩盖了区域减排本应带来的下降趋势。研究结果表明，在评估环境政策成效时必须考虑气候介导的汞再活化过程——该过程可能施加一种气候变化驱动的“惩罚”，延迟生态系统的恢复。

（来源：Environmental Science & Technology 2026 Issue 16  DOI: 10.1021/acs.est.5c16308）