Isotopic Characterization of Mercury Atmosphere–Foliage and Atmosphere–Soil Exchange in a Swiss Subalpine Coniferous Forest

• DOI: 10.1021/acs.est.3c03576
• Publication Date: 2023-10-03T21:15:14Z
• Authors: Chaoyue Chen; Jen-How Huang; Kai Li; Stefan Osterwalder; Chenmeng Yang; Peter Waldner; Hui Zhang; Xuewu Fu; Xinbin Feng
• Keywords: Biogeochemical Cycle; Trace gas; Soil gas; Sink (geography)

To understand the role of vegetation and soil in regulating atmospheric Hg0, exchange fluxes isotope signatures Hg were characterized using a dynamic flux bag/chamber at atmosphere-foliage/soil interfaces Davos-Seehornwald forest, Switzerland. The foliage was net Hg0 sink took up preferentially light isotopes, consequently resulting large shifts (-3.27‰) δ202Hg values. served mostly as sources with higher emission from moss-covered soils than bare soils. negative shift Δ199Hg values efflux air relative to ambient Δ199Hg/Δ201Hg ratio among air, pore gas highlight that re-emission strongly constrained by evasion together microbial reduction. isotopic mass balance model indicates 8.4 times caused surface photoreduction. Deposition noticeably 3.2 foliage, reflecting high significance influence signatures. This study improves our understanding subalpine coniferous forests, which is indispensable assessment forest biogeochemical cycling.