title: Mass balance assessment for mercury in Lake Champlain.
abstract: A mass balance model for mercury in Lake Champlain was developed in an effort to understand the sources, inventories, concentrations, and effects of mercury (Hg) contamination in the lake ecosystem. To construct the mass balance model, air, water, and sediment were sampled as a part of this project and other research/monitoring projects in the Lake Champlain Basin. This project produced a STELLA-based computer model and quantitative apportionments of the principal input and output pathways of Hg for each of 13 segments in the lake. The model Hg concentrations in the lake were consistent with measured concentrations. Specifically, the modeling identified surface water inflows as the largest direct contributor of Hg into the lake. Direct wet deposition to the lake was the second largest source of Hg followed by direct dry deposition. Volatilization and sedimentation losses were identified as the two major removal mechanisms. This study significantly improves previous estimates of the relative importance of Hg input pathways and of wet and dry deposition fluxes of Hg into Lake Champlain. It also provides new estimates of volatilization fluxes across different lake segments and sedimentation loss in the lake.
authors.affiliation: Department of Chemistry, St. Lawrence University, Canton, New York 13617, USA. ngao@stlawu.edu
authors.forename: Ning
authors.initials: N
authors.lastname: Gao
authors.forename: N Gabriel
authors.initials: NG
authors.lastname: Armatas
authors.forename: James B
authors.initials: JB
authors.lastname: Shanley
authors.forename: Neil C
authors.initials: NC
authors.lastname: Kamman
authors.forename: Eric K
authors.initials: EK
authors.lastname: Miller
authors.forename: Gerald J
authors.initials: GJ
authors.lastname: Keeler
authors.forename: Timothy
authors.initials: T
authors.lastname: Scherbatskoy
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Holsen
authors.forename: Thomas
authors.initials: T
authors.lastname: Young
authors.forename: Lyn
authors.initials: L
authors.lastname: McIlroy
authors.forename: Stephen
authors.initials: S
authors.lastname: Drake
authors.forename: Bill
authors.initials: B
authors.lastname: Olsen
authors.forename: Carol
authors.initials: C
authors.lastname: Cady
mesh_terms: D017753:Ecosystem; D004784:Environmental Monitoring; D006114:Great Lakes Region; D008628:Mercury / Q000032:analysis*; D018570:Risk Assessment; D014835:Volatilization; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D014874:Water Pollutants, Chemical; D008628:Mercury