Application of a rule-based model to estimate mercury exchange for three background biomes in the continental United States.
Ecosystems that have low mercury (Hg) concentrations (i.e., not enriched or impacted by geologic or anthropogenic processes) cover most of the terrestrial surface area of the earth yet their role as a net source or sink for atmospheric Hg is uncertain. Here we use empirical data to develop a rule-based model implemented within a geographic information system framework to estimate the spatial and temporal patterns of Hg flux for semiarid deserts, grasslands, and deciduous forests representing 45% of the continental United States. This exercise provides an indication of whether these ecosystems are a net source or sink for atmospheric Hg as well as a basis for recommendation of data to collect in future field sampling campaigns. Results indicated that soil alone was a small net source of atmospheric Hg and that emitted Hg could be accounted for based on Hg input by wet deposition. When foliar assimilation and wet deposition are added to the area estimate of soil Hg flux these biomes are a sink for atmospheric Hg.
Hartman
Jelena S
JS
Department of Natural Resources and Environmental Science, University of Nevada-Reno, 1664 N Virginia Street, MS 370, Reno, Nevada 89557, USA.
Weisberg
Peter J
PJ
Pillai
Rekha
R
Ericksen
Jody A
JA
Kuiken
Todd
T
Lindberg
Steve E
SE
Zhang
Hong
H
Rytuba
James J
JJ
Gustin
Mae S
MS
D000393:Air Pollutants / Q000032:analysis*; D001272:Atmosphere; D017753:Ecosystem; D004784:Environmental Monitoring / Q000379:methods*; D008628:Mercury / Q000032:analysis*; D018515:Plant Leaves / Q000378:metabolism; D012989:Soil Pollutants / Q000032:analysis*; D013997:Time Factors; D014197:Trees; D014481:United States; D014835:Volatilization
D000393:Air Pollutants; D012989:Soil Pollutants; D008628:Mercury