Estimation and Mapping of Wet and Dry Mercury Deposition Across Northeastern North America

Whereas many ecosystem characteristics and processes influence mercury accumulation in higher trophic-level organisms, the mercury flux from the atmosphere to a lake and its watershed is a likely factor in potential risk to biota. Atmospheric deposition clearly affects mercury accumulation in soils and lake sediments. Thus, knowledge of spatial patterns in atmospheric deposition may provide information for assessing the relative risk for ecosystems to exhibit excessive biotic mercury contamination. Atmospheric mercury concentrations in aerosol, vapor, and liquid phases from four observation networks were used to estimate regional surface concentration fields. Statistical models were developed to relate sparsely measured mercury vapor and aerosol concentrations to the more commonly measured mercury concentration in precipitation. High spatial resolution deposition velocities for different phases (precipitation, cloud droplets, aerosols, and reactive gaseous mercury (RGM)) were computed using inferential models. An empirical model was developed to estimate gaseous elemental mercury (GEM) deposition. Spatial patterns of estimated total mercury deposition were complex. Generally, deposition was higher in the southwest and lower in the northeast. Elevation, land cover, and proximity to urban areas modified the general pattern. The estimated net GEM and RGM fluxes were each greater than or equal to wet deposition in many areas. Mercury assimilation by plant foliage may provide a substantial input of methyl-mercury (MeHg) to ecosystems.

[1]  Poissant.  Total gaseous mercury in Quebec (Canada) in 1998 , 2000, The Science of the total environment.

[2]  Lawrence Dingman,et al.  Elevation: a major influence on the hydrology of New Hampshire and Vermont, USA / L'altitude exerce une influence importante sur l'hydrologie du New Hampshire et du Vermont, Etats-Unis , 1981 .

[3]  Michael J. Oimoen,et al.  The National Elevation Dataset , 2002 .

[4]  T. Meyers,et al.  Air/surface exchange of mercury vapor over forests-the need for a reassessment of continental biogenic emissions , 1998 .

[5]  A. Richter,et al.  Dynamic oxidation of gaseous mercury in the Arctic troposphere at polar sunrise. , 2002, Environmental science & technology.

[6]  J. Coleman,et al.  Experimental evidence against diffusion control of Hg evasion from soils. , 2003, The Science of the total environment.

[7]  L. Poissant,et al.  Water-air and soil-air exchange rate of total gaseous mercury measured at background sites , 1998 .

[8]  R. R. Turner,et al.  Atmosphere-surface exchange of mercury in a forest: Results of modeling and gradient approaches , 1992 .

[9]  R. Mason,et al.  Monitoring the response to changing mercury deposition. , 2005, Environmental science & technology.

[10]  W. Schlesinger.  Carbon Balance in Terrestrial Detritus , 1977 .

[11]  D. Johnson,et al.  The biogeochemical cycling of Hg in forests: Alternative methods for quantifying total deposition and soil emission , 1995 .

[12]  W. Belzer,et al.  Temporal and spatial variability of total gaseous mercury in Canada : Results from the Canadian Atmospheric Mercury Measurement Network (CAMNet) , 2003 .

[13]  P. Rasmussen.  Temporal Variation of Mercury in Vegetation , 1995 .

[14]  R. Draxler,et al.  Modeling the atmospheric transport and deposition of mercury to the Great Lakes. , 2004, Environmental research.

[15]  M. Pilote,et al.  Atmospheric mercury speciation and deposition in the Bay St. François wetlands , 2004 .

[16]  Elizabeth G. Malcolm,et al.  Mercury and trace elements in cloud water and precipitation collected on Mt. Mansfield, Vermont. , 2003, Journal of environmental monitoring : JEM.

[17]  X. Lee,et al.  Total gaseous mercury concentration and flux over a coastal saltmarsh vegetation in Connecticut, USA , 2000 .

[18]  G. Keeler,et al.  Wet deposition of mercury and ambient mercury concentrations at a site in the Lake Champlain basin , 1995 .

[19]  A. J. Friedland,et al.  Atmospheric deposition to a high‐elevation forest at Whiteface Mountain, New York, USA , 1993 .

[20]  J. Munthe,et al.  Do concepts about catchment cycling of methylmercury and mercury in boreal catchments stand the test of time? Six years of atmospheric inputs and runoff export at Svartberget, northern Sweden. , 2000, The Science of the total environment.

[21]  D. F. Grigal.  Inputs and outputs of mercury from terrestrial watersheds: a review , 2002 .

[22]  S. Pehkonen,et al.  The chemistry of atmospheric mercury: a review , 1999 .

[23]  S. Lindberg,et al.  Dry deposition and foliar leaching of mercury and selected trace elements in deciduous forest throughfall , 2001 .

[24]  G. Boulet,et al.  Patterns of Mercury Deposition and Concentration in Northeastern North America (1996–2002) , 2005, Ecotoxicology.

[25]  Andrew J. Friedland,et al.  Atmospheric deposition to forests along an elevational gradient at Whiteface Mountain, NY, U.S.A. , 1993 .

[26]  R. Stevens,et al.  Development and characterization of an annular denuder methodology for the measurement of divalent inorganic reactive gaseous mercury in ambient air. , 2002, Environmental science & technology.

[27]  Ki‐Hyun Kim,et al.  Foliar exchange of mercury vapor: Evidence for a compensation point , 1995 .

[28]  S. Lindberg,et al.  Mercury Accumulation in Foliage over Time in Two Northern Mixed-Hardwood Forests , 2002 .

[29]  J. Shanley,et al.  Factors Controlling Mercury Transport in an Upland Forested Catchment , 1998 .

[30]  D. Engstrom,et al.  Historical and present fluxes of mercury to Vermont and New Hampshire lakes inferred from 210Pb dated sediment cores , 2002 .

[31]  E. Matzner,et al.  Pools and fluxes of mercury and methylmercury in two forested catchments in Germany. , 2000, The Science of the total environment.

[32]  T. Meyers,et al.  Transpiration of gaseous elemental mercury through vegetation in a subtropical wetland in Florida. , 2002 .

[33]  S. Running,et al.  The impact of growing-season length variability on carbon assimilation and evapotranspiration over 88 years in the eastern US deciduous forest , 1999, International journal of biometeorology.

[34]  Elizabeth G. Malcolm,et al.  Measurements of mercury in dew: atmospheric removal of mercury species to a wetted surface. , 2002, Environmental science & technology.

[35]  David R. Miller,et al.  Formulation of bi-directional atmosphere-surface exchanges of elemental mercury , 1999 .

[36]  D. E. Schorran,et al.  Accumulation of atmospheric mercury in forest foliage , 2003 .

[37]  David R. Miller,et al.  Northeast United States and Southeast Canada natural mercury emissions estimated with a surface emission model , 2004 .

[38]  L. Hove,et al.  The annual variation in stomatal ammonia compensation point of rye grass (Lolium perenne L.) leaves in an intensively managed grassland , 2002 .

[39]  J. Rudd,et al.  Importance of the forest canopy to fluxes of methyl mercury and total mercury to boreal ecosystems. , 2001, Environmental science & technology.

[40]  C. Cobbett.  Phytochelatins and their roles in heavy metal detoxification. , 2000, Plant physiology.

[41]  S. Norton,et al.  Factors Influencing Mercury in Freshwater Surface Sediments of Northeastern North America , 2005, Ecotoxicology.

[42]  T. Meyers,et al.  Development of an automated micrometeorological method for measuring the emission of mercury vapor from wetland vegetation , 2001, Wetlands Ecology and Management.

[43]  Limin Yang,et al.  COMPLETION OF THE 1990S NATIONAL LAND COVER DATA SET FOR THE CONTERMINOUS UNITED STATES FROM LANDSAT THEMATIC MAPPER DATA AND ANCILLARY DATA SOURCES , 2001 .

[44]  S. E. Lindberg,et al.  Atmospheric Mercury Speciation: Concentrations and Behavior of Reactive Gaseous Mercury in Ambient Air , 1998 .

[45]  P. Blanchard,et al.  Four years of continuous total gaseous mercury (TGM) measurements at sites in Ontario, Canada , 2002 .