title: Spatial patterns of mercury in biota of Adirondack, New York lakes.
abstract: We studied the spatial distribution patterns of mercury (Hg) in lake water, littoral sediments, zooplankton, crayfish, fish, and common loons in 44 lakes of the Adirondacks of New York State, USA, a region that has been characterized as a "biological Hg hotspot". Our study confirmed this pattern, finding that a substantial fraction of the lakes studied had fish and loon samples exceeding established criteria for human and wildlife health. Factors accounting for the spatial variability of Hg in lake water and biota were lake chemistry (pH, acid neutralizing capacity (ANC), percent carbon in sediments), biology (taxa presence, trophic status) and landscape characteristics (land cover class, lake elevation). Hg concentrations in zooplankton, fish and common loons were negatively associated with the lake water acid-base status (pH, ANC). Bioaccumulation factors (BAF) for methyl Hg (MeHg) increased from crayfish (mean log(10) BAF = 5.7), to zooplankton (5.9), to prey fish (6.2), to larger fish (6.3), to common loons (7.2). MeHg BAF values in zooplankton, crayfish, and fish (yellow perch equivalent) all increased with increasing lake elevation. Our findings support the hypothesis that bioaccumulation of MeHg at the base of the food chain is an important controller of Hg concentrations in taxa at higher trophic levels. The characteristics of Adirondack lake-watersheds (sensitivity to acidic deposition; significant forest and wetland land cover; and low nutrient inputs) contribute to elevated Hg concentrations in aquatic biota.
authors.affiliation: Department of Civil and Environmental Engineering, Syracuse University, Syracuse, NY 13244, USA. xuyu@syr.edu
authors.forename: Xue
authors.initials: X
authors.lastname: Yu
authors.forename: Charles T
authors.initials: CT
authors.lastname: Driscoll
authors.forename: Mario
authors.initials: M
authors.lastname: Montesdeoca
authors.forename: David
authors.initials: D
authors.lastname: Evers
authors.forename: Melissa
authors.initials: M
authors.lastname: Duron
authors.forename: Kate
authors.initials: K
authors.lastname: Williams
authors.forename: Nina
authors.initials: N
authors.lastname: Schoch
authors.forename: Neil C
authors.initials: NC
authors.lastname: Kamman
mesh_terms: D000818:Animals; D003400:Astacoidea; D058448:Biota; D001717:Birds; D004784:Environmental Monitoring / Q000379:methods; D005399:Fishes; D020387:Food Chain; D019015:Geologic Sediments / Q000032:analysis; D060106:Lakes / Q000737:chemistry*; D016014:Linear Models; D008628:Mercury / Q000032:analysis* / Q000737:chemistry / Q000493:pharmacokinetics*; D008767:Methylmercury Compounds / Q000032:analysis / Q000737:chemistry / Q000493:pharmacokinetics; D009518:New York; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000737:chemistry / Q000493:pharmacokinetics*; D053833:Wetlands; D015048:Zooplankton
chemical_list: D008767:Methylmercury Compounds; D014874:Water Pollutants, Chemical; D008628:Mercury