TY - JOUR

T1 - Spatial and Temporal Patterns in Atmospheric Deposition of Dissolved Organic Carbon

AU - Liptzin, Daniel

AU - Boy, Jens

AU - Campbell, John L.

AU - Clarke, Nicholas

AU - Laclau, Jean‐Paul

AU - Godoy, Roberto

AU - Johnson, Sherri L.

AU - Kaiser, Klaus

AU - Likens, Gene E.

AU - Karlsson, Gunilla Pihl

AU - Markewitz, Daniel

AU - Rogora, Michela

AU - Sebestyen, Stephen D.

AU - Shanley, James B.

AU - Vanguelova, Elena

AU - Verstraeten, Arne

AU - Wilcke, Wolfgang

AU - Worrall, Fred

AU - McDowell, William H.

N1 - Funding Information: This synthesis was conducted with support provided by the New Hampshire Agricultural Experiment Station. This is Scientific Contribution Number 2946. This work was supported by the USDA National Institute of Food and Agriculture McIntire‐Stennis Project 1019522. The Luquillo LTER (NSF DEB 1831592) and Miguel Leon provided support for data set and manuscript preparation. The data for the sites in Italy were assessed and submitted within ICP Forests and under relevant EC Regulations and partially funded by LIFE+ 07/ENV D000218 “FutMon” (Further Development and Implementation of an EU‐level Forest Monitoring System). The authors would like to thank Mark W. Williams of the University of Colorado for providing data for one site.

PY - 2022/10/17

Y1 - 2022/10/17

N2 - Atmospheric deposition of dissolved organic carbon (DOC) to terrestrial ecosystems is a small, but rarely studied component of the global carbon (C) cycle. Emissions of volatile organic compounds (VOC) and organic particulates are the sources of atmospheric C and deposition represents a major pathway for the removal of organic C from the atmosphere. Here, we evaluate the spatial and temporal patterns of DOC deposition using 70 data sets at least one year in length ranging from 40° south to 66° north latitude. Globally, the median DOC concentration in bulk deposition was 1.7 mg L −1. The DOC concentrations were significantly higher in tropical (<25°) latitudes compared to temperate (>25°) latitudes. DOC deposition was significantly higher in the tropics because of both higher DOC concentrations and precipitation. Using the global median or latitudinal specific DOC concentrations leads to a calculated global deposition of 202 or 295 Tg C yr −1 respectively. Many sites exhibited seasonal variability in DOC concentration. At temperate sites, DOC concentrations were higher during the growing season; at tropical sites, DOC concentrations were higher during the dry season. Thirteen of the thirty-four long-term (>10 years) data sets showed significant declines in DOC concentration over time with the others showing no significant change. Based on the magnitude and timing of the various sources of organic C to the atmosphere, biogenic VOCs likely explain the latitudinal pattern and the seasonal pattern at temperate latitudes while decreases in anthropogenic emissions are the most likely explanation for the declines in DOC concentration.

AB - Atmospheric deposition of dissolved organic carbon (DOC) to terrestrial ecosystems is a small, but rarely studied component of the global carbon (C) cycle. Emissions of volatile organic compounds (VOC) and organic particulates are the sources of atmospheric C and deposition represents a major pathway for the removal of organic C from the atmosphere. Here, we evaluate the spatial and temporal patterns of DOC deposition using 70 data sets at least one year in length ranging from 40° south to 66° north latitude. Globally, the median DOC concentration in bulk deposition was 1.7 mg L −1. The DOC concentrations were significantly higher in tropical (<25°) latitudes compared to temperate (>25°) latitudes. DOC deposition was significantly higher in the tropics because of both higher DOC concentrations and precipitation. Using the global median or latitudinal specific DOC concentrations leads to a calculated global deposition of 202 or 295 Tg C yr −1 respectively. Many sites exhibited seasonal variability in DOC concentration. At temperate sites, DOC concentrations were higher during the growing season; at tropical sites, DOC concentrations were higher during the dry season. Thirteen of the thirty-four long-term (>10 years) data sets showed significant declines in DOC concentration over time with the others showing no significant change. Based on the magnitude and timing of the various sources of organic C to the atmosphere, biogenic VOCs likely explain the latitudinal pattern and the seasonal pattern at temperate latitudes while decreases in anthropogenic emissions are the most likely explanation for the declines in DOC concentration.

KW - atmospheric deposition

KW - carbon cycling

KW - dissolved organic carbon

KW - global synthesis

KW - precipitation chemistry

UR - http://www.scopus.com/inward/record.url?scp=85141735164&partnerID=8YFLogxK

U2 - 10.1029/2022GB007393

DO - 10.1029/2022GB007393

M3 - Article

VL - 36

JO - Global biogeochemical cycles

JF - Global biogeochemical cycles

SN - 0886-6236

IS - 10

M1 - e2022GB007393

ER -