Characterizing the Atmospheric Mn Cycle and Its Impact on Terrestrial Biogeochemistry

The role of manganese (Mn) in ecosystem carbon (C) biogeochemical cycling is gaining increasing attention. While soil Mn is mainly derived from bedrock, atmospheric deposition could be a major source of Mn to surface soils, with implications for soil C cycling. However, quantification of the atmospheric Mn cycle, which comprises emissions from natural (desert dust, sea salts, volcanoes, primary biogenic particles, and wildfires) and anthropogenic sources (e.g., industrialization and land-use change due to agriculture), transport, and deposition, remains uncertain. Here, we use compiled emission data sets for each identified source to model and quantify the atmospheric Mn cycle by combining an atmospheric model and in situ atmospheric concentration measurements. We estimated global emissions of atmospheric Mn in aerosols (<10 μm in aerodynamic diameter) to be 1,400 Gg Mn year−1. Approximately 31% of the emissions come from anthropogenic sources. Deposition of the anthropogenic Mn shortened Mn “pseudo” turnover times in 1-m-thick surface soils (ranging from 1,000 to over 10,000,000 years) by 1–2 orders of magnitude in industrialized regions. Such anthropogenic Mn inputs boosted the Mn-to-N ratio of the atmospheric deposition in non-desert dominated regions (between 5 × 10−5 and 0.02) across industrialized areas, but that was still lower than soil Mn-to-N ratio by 1–3 orders of magnitude. Correlation analysis revealed a negative relationship between Mn deposition and topsoil C density across temperate and (sub)tropical forests, consisting with atmospheric Mn deposition enhancing carbon respiration as seen in in situ biogeochemical studies.

Bibliographic Details

Main Authors:	Lu, Louis, Li, Longlei, Rathod, Sagar, Hess, Peter, Martínez, Carmen, Fernandez, Nicole, Goodale, Christine, Thies, Janice, Wong, Michelle Y., Alaimo, Maria Grazia, Artaxo, Paulo, Barraza, Francisco, Barreto, Africa, Beddows, David, Chellam, Shankarararman, Chen, Ying, Chuang, Patrick, Cohen, David D., Dongarrà, Gaetano, Gaston, Cassandra, Gómez, Darío, Morera-Gómez, Yasser, Hakola, Hannele, Hand, Jenny, Harrison, Roy, Hopke, Philip, Hueglin, Christoph, Kuang, Yuan-Wen, Kyllönen, Katriina, Lambert, Fabrice, Maenhaut, Willy, Martin, Randall, Paytan, Adina, Prospero, Joseph, González, Yenny, Rodríguez, Sergio, Smichowski, Patricia, Varrica, Daniela, Walsh, Brenna, Weagle, Crystal, Xiao, Yi-Hua, Mahowald, Natalie
Other Authors:	European Commission
Format:	artículo biblioteca
Language:	English
Published:	John Wiley & Sons 2024-03-27
Subjects:	Atmospheric, Mn cycle, Mn deposition, C turnover, Community Earth System Model (CESM), aerosol modeling, terrestial ecosystem, atmospheric circulation, Terrestrial ecosystems,
Online Access:	http://hdl.handle.net/10261/370477 http://dx.doi.org/10.13039/501100000780 http://dx.doi.org/10.13039/501100004837 http://dx.doi.org/10.13039/501100011033
Tags:	Add Tag No Tags, Be the first to tag this record!