Mercury bioaccumulation in aquatic biota along a salinity gradient in the Saint John River estuary  

作　　者：Bethany L.Reinhart Karen A.Kidd R.Allen Curry Nelson J.O’Driscoll Scott A.Pavey 

机构地区：[1]Department of Biology and Canadian Rivers Institute, University of New Brunswick Saint John, Saint John, New Brunswick E2L4L5, Canada [2]Department of Biology, Forestry and Environmental Management, and Canadian Rivers Institute, University of New Brunswick, Fredericton, New Brunswick E3B4A3, Canada [3]Department of Earth and Environmental Sciences, Acadia University, Wolfville, Nova Scotia B4P2R6, Canada [4]Department of Biology and School of Geography & Earth Sciences, McMaster University, Hamilton, Ontario LSS 4K1, Canada

出　　处：《Journal of Environmental Sciences》2018年第6期41-54,共14页环境科学学报（英文版）

基　　金：The Natural Sciences and Engineering Research Council of Canada (NSERC) Collaborative Research and Development program (#CRDPJ 462708-13);Discovery Program (#3122372012);Canada Research Chairs (#950-230607);Canada Foundation for Innovation (#201843)programs;NB Power (#CRDPJ 462708-13) provided funding for this research

摘　　要：Although estuaries are critical habitats for many aquatic species, the spatial trends of toxic methylmercury（MeHg） in biota from fresh to marine waters are poorly understood. Our objective was to determine if MeHg concentrations in biota changed along a salinity gradient in an estuary. Fourspine Stickleback（Apeltes quadracus）, invertebrates（snails,amphipods, and chironomids）, sediments, and water were collected from ten sites along the Saint John River estuary, New Brunswick, Canada in 2015 and 2016, with salinities ranging from 0.06 to 6.96. Total mercury（proxy for MeHg） was measured in whole fish and MeHg was measured in a subset of fish, pooled invertebrates, sediments, and water. Stable sulfur（δ34S）, carbon（δ13 C）, and nitrogen（δ15N） isotope values were measured to assess energy sources（S, C） and relative trophic level（N）. There were increases in biotic δ13C and δ34S from fresh to more saline sites and these measures were correlated with salinity.Though aqueous MeHg was higher at the freshwater than more saline sites, only chironomid MeHg increased significantly with salinity. In the Saint John River estuary, there was little evidence that MeHg and its associated risks increased along a salinity gradient.Although estuaries are critical habitats for many aquatic species, the spatial trends of toxic methylmercury（MeHg） in biota from fresh to marine waters are poorly understood. Our objective was to determine if MeHg concentrations in biota changed along a salinity gradient in an estuary. Fourspine Stickleback（Apeltes quadracus）, invertebrates（snails,amphipods, and chironomids）, sediments, and water were collected from ten sites along the Saint John River estuary, New Brunswick, Canada in 2015 and 2016, with salinities ranging from 0.06 to 6.96. Total mercury（proxy for MeHg） was measured in whole fish and MeHg was measured in a subset of fish, pooled invertebrates, sediments, and water. Stable sulfur（δ34S）, carbon（δ13 C）, and nitrogen（δ15N） isotope values were measured to assess energy sources（S, C） and relative trophic level（N）. There were increases in biotic δ13C and δ34S from fresh to more saline sites and these measures were correlated with salinity.Though aqueous MeHg was higher at the freshwater than more saline sites, only chironomid MeHg increased significantly with salinity. In the Saint John River estuary, there was little evidence that MeHg and its associated risks increased along a salinity gradient.

关 键 词：STICKLEBACK AMPHIPOD METHYLMERCURY BIOMAGNIFICATION Stable isotopes Food web 

分 类 号：X17[环境科学与工程—环境科学]