title: Contribution of atmospheric deposition to tissue concentrations of mercury in aquatic bryophytes.
abstract: In this biomonitoring study, we measured the temporal variations in concentrations of mercury in samples of aquatic bryophytes from rivers in a region that received large inputs of the metal via atmospheric deposition. In the first year of sampling, the presence of an important source of atmospheric deposition of Hg (a lignite-fired power plant) led, during the rainy season, to elevated concentrations of the metal in catchments situated downwind of the prevailing winds. High concentrations of the metal were even detected in samples from apparently clean rivers in isolated mountain sites within the downwind catchments. Substitution of the type of fuel (high quality imported carbon instead of brown coal) used in the power plant greatly reduced Hg emissions in subsequent years. Application of spatial interpolation techniques to dense monitoring networks with aquatic bryophytes, without taking into consideration the catchment borders, appears suitable for studying extensive atmospheric pollution derived from a large scale source of contamination. This study also demonstrates the importance of environmental specimen banks in retrospective studies of contamination, as they enable posterior analysis of contaminants that for various reasons cannot be analyzed at the time of sampling.
authors.affiliation: Departamento de Biología Celular y Ecología, Escuela Politécnica Superior, Universidade de Santiago de Compostela, 27002 Lugo, Spain. Electronic address: ruben.villares@usc.es.
authors.forename: Rubén
authors.initials: R
authors.lastname: Villares
authors.affiliation: Departamento de Biología Celular y Ecología, Facultad de Biología, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain.
authors.forename: Santiago
authors.initials: S
authors.lastname: Díaz
authors.affiliation: Departamento de Ecología y Biología Animal, Facultad de Ciencias, Universidade de Vigo, 36310 Vigo, Spain.
authors.forename: Jesús
authors.initials: J
authors.lastname: López
authors.affiliation: Departamento de Biología Celular y Ecología, Escuela Politécnica Superior, Universidade de Santiago de Compostela, 27002 Lugo, Spain.
authors.forename: Maria Dolores
authors.initials: MD
authors.lastname: Vázquez
authors.affiliation: Departamento de Biología Celular y Ecología, Facultad de Biología, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain.
authors.forename: Alejo
authors.initials: A
authors.lastname: Carballeira
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D059001:Aquatic Organisms / Q000737:chemistry*; D044002:Bryophyta / Q000737:chemistry*; D003031:Coal; D004784:Environmental Monitoring / Q000379:methods*; D004787:Environmental Pollution / Q000032:analysis*; D007220:Industrial Waste / Q000032:analysis; D008628:Mercury / Q000032:analysis*; D011210:Power Plants; D012189:Retrospective Studies; D012989:Soil Pollutants / Q000032:analysis*; D013030:Spain; D013997:Time Factors
chemical_list: D000393:Air Pollutants; D003031:Coal; D007220:Industrial Waste; D012989:Soil Pollutants; D008628:Mercury
keywords: Biomonitoring; Environmental specimen bank; Interpolation; Power station