A Spatial Assessment of Current and Future Foliar Hg Uptake Fluxes Across European Forests
Name
Global Biogeochemical Cycles - 2023 - Wohlgemuth - A Spatial Assessment of Current and Future Foliar Hg Uptake Fluxes.pdf
Size
1.07 MB
Format
Adobe PDF
Checksum (MD5)
37dd8e9d5dd322686783a225c77394cc
Author(s)
Wohlgemuth, Lena
Feinberg, Aryeh
Buras, Allan
Jiskra, Martin
Date Issued
September 28, 2023
Journal
Global Biogeochemical Cycles
Publisher
American Geophysical Union
Citation
Wohlgemuth, L., Feinberg, A., Buras, A., & Jiskra, M. (2023). A spatial assessment of current and future foliar Hg uptake fluxes across European forests. Global Biogeochemical Cycles, 37, e2023GB007833.
Version
Final published version
Abstract
Atmospheric mercury (Hg) is deposited to land surfaces mainly through vegetation uptake. Foliage stomatal gas exchange plays an important role for net vegetation Hg uptake, because foliage assimilates Hg via the stomata. Here, we use empirical relationships of foliar Hg uptake by forest tree species to produce a spatially highly resolved (1 km2) map of foliar Hg fluxes to European forests over one growing season. The modeled forest foliar Hg uptake flux is 23 ± 12 Mg Hg season−1, which agrees with previous estimates from literature. We spatially compared forest Hg fluxes with modeled fluxes of the chemical transport model GEOS-Chem and find a good overall agreement. For European pine forests, stomatal Hg uptake was shown to be sensitive to prevailing conditions of relatively high ambient water vapor pressure deficit (VPD). We tested a stomatal uptake model for the total pine needle Hg uptake flux during four previous growing seasons (1994, 2003, 2015/2017, 2018) and two climate change scenarios (RCP 4.5 and RCP 8.5). The resulting modeled total European pine needle Hg uptake fluxes are in a range of 8.0–9.3 Mg Hg season−1 (min–max). The lowest pine forest needle Hg uptake flux to Europe (8 Mg Hg season−1) among all investigated growing seasons was associated with unusually hot and dry ambient conditions in the European summer 2018, highlighting the sensitivity of the investigated flux to prolonged high VPD. We conclude, that stomatal modeling is particularly useful to investigate changes in Hg deposition in the context of extreme climate events.
MIT Department
Massachusetts Institute of Technology. Institute for Data, Systems, and Society
Terms of Use
Creative Commons Attribution-NonCommercial
Persistent DSpace Link
DOI of Published Version
https://doi. org/10.1029/2023GB007833
