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Characterization of PBDEs in soils and vegetations near an e-waste recycling site in South China 全文
2011
Wang, Yan | Luo, Chunling | Li, Jun | Yin, Hua | Li, Xiangdong | Zhang, Gan
The concentration and composition of PBDEs in the soils and plants near a typical e-waste recycling site in South China were investigated. The total concentration of PBDEs (ΣPBDEs) in soil ranged from 4.8 to 533 ng/g dry wt. The ΣPBDEs in vegetation were from 2.1 to 217 ng/g dry wt. For the vegetable, the highest concentration of 19.9 ng/g dry wt. was observed in the shoot of Brassica alboglabra L. BDE 209 was the predominant congener in all samples. In comaprison with other e-waste contaminated sites in China, lower concentrations of PBDEs and higher concentrations of PCBs were observed in both soils and plants suggesting different e-waste types involved in the present study. The PBDEs contaminated vegetables around the e-waste dismantling site may pose a potential health risk to the local inhabitants.
显示更多 [+] 显示较少 [-]Will PM control undermine China’s efforts to reduce soil acidification? 全文
2011
Zhao, Yu | Duan, Lei | Lei, Yu | Xing, Jia | Nielsen, Chris P. | Hao, Jiming
China’s strategies to control acidifying pollutants and particulate matter (PM) may be in conflict for soil acidification abatement. Acidifying pollutant emissions are estimated for 2005 and 2020 with anticipated control policies. PM emissions including base cations (BCs) are evaluated with two scenarios, a base case applying existing policy to 2020, and a control case including anticipated tightened measures. Depositions of sulfur (S), nitrogen (N) and BCs are simulated and their acidification risks are evaluated with critical load (CL). In 2005, the area exceeding CL covered 15.6% of mainland China, with total exceedance of 2.2 Mt S. These values decrease in the base scenario 2020, implying partial recovery from acidification. Under more realistic PM control, the respective estimates are 17.9% and 2.4 Mt S, indicating increased acidification risks due to abatement of acid-neutralizing BCs. China’s anthropogenic PM abatement will have potentially stronger chemical implications for acidification than developed countries.
显示更多 [+] 显示较少 [-]Blood dynamics of mercury and selenium in northern elephant seals during the lactation period 全文
2011
Blood dynamics of mercury and selenium in northern elephant seals during the lactation period 全文
2011
The effects of reproduction and maternal investment (i.e., milk transfer) on trace element levels remain poorly understood in marine mammals. We examined the blood dynamics of mercury (Hg) and selenium (Se) during lactation in the northern elephant seal (Mirounga angustirostris), a top predator from the North Pacific Ocean. Total Hg and Se levels were measured in whole blood and milk of 10 mother–pup pairs on days 5 and 22 of lactation. Both Hg and Se were transferred to offspring through the milk. Results suggested that the maternal transfer of Se was prominent during lactation, whereas the Hg transfer was larger during gestation. The lactation period affected Hg and Se levels in the blood of elephant seal mothers and pups. Physiological processes and their relationship to body condition should be considered carefully when interpreting trace element levels in the framework of biomonitoring.
显示更多 [+] 显示较少 [-]Blood dynamics of mercury and selenium in northern elephant seals during the lactation period 全文
2011
Habran, Sarah | Debier, Cathy | Crocker, Dan | Houser, Dorian | Das, Krishna
The effects of reproduction and maternal investment (i.e., milk transfer) on trace element levels remain poorly understood in marine mammals. We examined the blood dynamics of mercury (Hg) and selenium (Se) during lactation in the northern elephant seal (Mirounga angustirostris), a top predator from the North Pacific Ocean. Total Hg and Se levels were measured in whole blood and milk of 10 mother-pup pairs on days 5 and 22 of lactation. Both Hg and Se were transferred to offspring through the milk. Results suggested that the maternal transfer of Se was prominent during lactation, whereas the Hg transfer was larger during gestation. The lactation period affected Hg and Se levels in the blood of elephant seal mothers and pups. Physiological processes and their relationship to body condition should be considered carefully when interpreting trace element levels in the framework of biomonitoring. | Fonds de la Recherche Scientifique (Communauté française de Belgique) - F.R.S.-FNRS
显示更多 [+] 显示较少 [-]Blood dynamics of mercury and selenium in northern elephant seals during the lactation period 全文
2011
Habran, Sarah | Debier, Cathy | Crocker, Dan | Houser, Dorian | Das, Krishna
peer reviewed | The effects of reproduction and maternal investment (i.e., milk transfer) on trace element levels remain poorly understood in marine mammals. We examined the blood dynamics of mercury (Hg) and selenium (Se) during lactation in the northern elephant seal (Mirounga angustirostris), a top predator from the North Pacific Ocean. Total Hg and Se levels were measured in whole blood and milk of 10 mother-pup pairs on days 5 and 22 of lactation. Both Hg and Se were transferred to offspring through the milk. Results suggested that the maternal transfer of Se was prominent during lactation, whereas the Hg transfer was larger during gestation. The lactation period affected Hg and Se levels in the blood of elephant seal mothers and pups. Physiological processes and their relationship to body condition should be considered carefully when interpreting trace element levels in the framework of biomonitoring.
显示更多 [+] 显示较少 [-]Farm, land, and soil nitrogen budgets for agriculture in Europe calculated with CAPRI 全文
2011
Leip, Adrian | Britz, Wolfgang | Weiss, Franz | de Vries, Wim
Farm, land, and soil nitrogen budgets for agriculture in Europe calculated with CAPRI 全文
2011
Leip, Adrian | Britz, Wolfgang | Weiss, Franz | de Vries, Wim
We calculated farm, land, and soil N-budgets for countries in Europe and the EU27 as a whole using the agro-economic model CAPRI. For EU27, N-surplus is 55 kg N ha⁻¹ yr⁻¹ in a soil budget and 65 kg N₂O–N ha⁻¹ yr⁻¹ and 67 kg N ha⁻¹ yr⁻¹ in land and farm budgets, respectively. NUE is 31% for the farm budget, 60% for the land budget and 63% for the soil budget. NS values are mainly related to the excretion (farm budget) and application (soil and land budget) of manure per hectare of total agricultural land. On the other hand, NUE is best explained by the specialization of the agricultural system toward animal production (farm NUE) or the share of imported feedstuff (soil NUE). Total N input, intensive farming, and the specialization to animal production are found to be the main drivers for a high NS and low NUE.
显示更多 [+] 显示较少 [-]Farm, Land, and Soil Nitrogen Budgets for Agriculture in Europe Calculated with CAPRI. 全文
2011
LEIP Adrian | BRITZ Wolfgang | WEISS Franz | DE VRIES W.
We calculated farm, land, and soil N-budgets for countries in Europe and the EU27 as a whole using the agro-economic model CAPRI. For EU27, N-surplus is 55 kg N ha(-1) yr(-1) in a soil budget and 65 kg N(2)O-N ha(-1) yr(-1) and 67 kg N ha(-1) yr(-1) in land and farm budgets, respectively. NUE is 31% for the farm budget, 60% for the land budget and 63% for the soil budget. NS values are mainly related to the excretion (farm budget) and application (soil and land budget) of manure per hectare of total agricultural land. On the other hand, NUE is best explained by the specialization of the agricultural system toward animal production (farm NUE) or the share of imported feedstuff (soil NUE). Total N input, intensive farming, and the specialization to animal production are found to be the main drivers for a high NS and low NUE. | JRC.H.4 - Monitoring Agricultural Resources
显示更多 [+] 显示较少 [-]Mechanisms of enhanced mobilisation of trace metals by anionic surfactants in soil 全文
2011
Hernández-Soriano, Maria del Carmen | Degryse, Fien | Smolders, Erik
Mechanisms of enhanced mobilisation of trace metals by anionic surfactants in soil 全文
2011
Hernández-Soriano, Maria del Carmen | Degryse, Fien | Smolders, Erik
Long-term applications of small concentrations of surfactants in soil via wastewater irrigation or pesticide application may enhance trace metal solubility. Mechanisms by which anionic surfactants (Aerosol 22, SDS and Biopower) affect trace metal solubility were assessed using batch, incubation and column experiments. In batch experiments on seven soils, the concentrations of Cu, Cd, Ni and Zn in the dissolved fraction of soils increased up to 100-fold at the high application rates, but increased less than 1.5-fold below the critical micelle concentration. Dissolved metal concentrations were less than 20% affected by surfactants in long-term incubations (70 days) up to the largest dose of 200 mg C kg⁻¹ soil. Leaching soil columns with A22 (100–1000 mg C L⁻¹) under unsaturated conditions increased trace metal concentrations in the leachates 2–4 fold over the control. Correlation analysis and speciation modelling showed that the increased solubility of metals upon surfactant application was more related to the solubilisation of soil organic matter from soil than to complexation of the metals with the surfactant. Organic matter from soil was solubilised in response to a decrease of solution Ca²⁺ as a result of Ca–surfactant precipitation. At environmentally relevant concentrations, surfactant application is unlikely to have a significant effect on trace metal mobility.
显示更多 [+] 显示较少 [-]Mechanisms of enhanced mobilisation of trace metals by anionic surfactants in soil 全文
2011
Hernández-Soriano, M.D.C. | Degryse, F. | Smolders, E.
Abstract not available | Maria del Carmen Hernández-Soriano, Fien Degryse and Erik Smolders
显示更多 [+] 显示较少 [-]Groundwater quality assessment of one former industrial site in Belgium using a TRIAD-like approach 全文
2011
Crévecoeur, Sophie | Debacker, Virginie | Joaquim-Justo, Célia | Gobert, Sylvie | Scippo, Marie-Louise | Dejonghe, Winnie | Martin, Patrick | Thomé, Jean-Pierre
Groundwater quality assessment of one former industrial site in Belgium using a TRIAD-like approach 全文
2011
Crévecoeur, Sophie | Debacker, Virginie | Joaquim-Justo, Célia | Gobert, Sylvie | Scippo, Marie-Louise | Dejonghe, Winnie | Martin, Patrick | Thomé, Jean-Pierre
Contaminated industrial sites are important sources of pollution and may result in ecotoxicological effects on terrestrial, aquatic and groundwater ecosystems. An effect-based approach to evaluate and assess pollution-induced degradation due to contaminated groundwater was carried out in this study. The new concept, referred to as “Groundwater Quality TRIAD-like” (GwQT) approach, is adapted from classical TRIAD approaches. GwQT is based on measurements of chemical concentrations, laboratory toxicity tests and physico-chemical analyses. These components are combined in the GwQT using qualitative and quantitative (using zero to one subindices) integration approaches. The TRIAD approach is applied for the first time on groundwater from one former industrial site located in Belgium. This approach will allow the classification of sites into categories according to the degree of contaminant-induced degradation. This new concept is a starting point for groundwater characterization and is open for improvement and adjustment.
显示更多 [+] 显示较少 [-]Groundwater quality assessment of one former industrial site in Belgium using a TRIAD-like approach. | Evaluation de la qualité des eaux souterraines d'une friche industrielle belge suivant la méthodologie TRIAD. 全文
2011
Crévecoeur, Sophie | Debacker, Virginie | Joaquim-Justo, Célia | Gobert, Sylvie | Scippo, Marie-Louise | Dejonghe, Winnie | Martin, Patrick | Thomé, Jean-Pierre
Contaminated industrial sites are important sources of pollution and may result in ecotoxicological effects on terrestrial, aquatic and groundwater ecosystems. An effect-based approach to evaluate and assess pollution-induced degradation due to contaminated groundwater was carried out in this study.The new concept, referred to as “Groundwater Quality TRIAD-like” (GwQT) approach, is adapted from classical TRIAD approaches. GwQT is based on measurements of chemical concentrations, laboratory toxicity tests and physico-chemical analyses. These components are combined in the GwQT using qualitative and quantitative (using zero to one subindices)integration approaches. The TRIAD approach is applied for the first time on groundwater from one former industrial site located in Belgium. This approach will allow the classification of sites into categories according to the degree of contaminant-induced degradation. This new concept is a starting point for groundwater characterization and is open for improvement and adjustment. | Science of Sustainable Development (FRAC-WECO project, 2007-2010).
显示更多 [+] 显示较少 [-]Groundwater quality assessment of one former industrial site in Belgium using a TRIAD-like approach. | Evaluation de la qualité des eaux souterraines d'une friche industrielle belge suivant la méthodologie TRIAD. 全文
2011
Crévecoeur, Sophie | Debacker, Virginie | Joaquim-Justo, Célia | Gobert, Sylvie | Scippo, Marie-Louise | Dejonghe, Winnie | Martin, Patrick | Thomé, Jean-Pierre
peer reviewed | Contaminated industrial sites are important sources of pollution and may result in ecotoxicological effects on terrestrial, aquatic and groundwater ecosystems. An effect-based approach to evaluate and assess pollution-induced degradation due to contaminated groundwater was carried out in this study. The new concept, referred to as “Groundwater Quality TRIAD-like” (GwQT) approach, is adapted from classical TRIAD approaches. GwQT is based on measurements of chemical concentrations, laboratory toxicity tests and physico-chemical analyses. These components are combined in the GwQT using qualitative and quantitative (using zero to one subindices)integration approaches. The TRIAD approach is applied for the first time on groundwater from one former industrial site located in Belgium. This approach will allow the classification of sites into categories according to the degree of contaminant-induced degradation. This new concept is a starting point for groundwater characterization and is open for improvement and adjustment. | Science of Sustainable Development (FRAC-WECO project, 2007-2010).
显示更多 [+] 显示较少 [-]TiO₂-based nanoparticles released in water from commercialized sunscreens in a life-cycle perspective: Structures and quantities 全文
2011
Botta, Céline | Labille, Jérôme | Auffan, Mélanie | Borschneck, Daniel | Miche, Hélène | Cabié, Martiane | Masion, Armand | Rose, Jerome | Bottero, Jean-Yves
TiO₂-based nanoparticles released in water from commercialized sunscreens in a life-cycle perspective: Structures and quantities 全文
2011
Botta, Céline | Labille, Jérôme | Auffan, Mélanie | Borschneck, Daniel | Miche, Hélène | Cabié, Martiane | Masion, Armand | Rose, Jerome | Bottero, Jean-Yves
This work investigates the physical–chemical evolution during artificial aging in water of four commercialized sunscreens containing TiO₂-based nanocomposites. Sunscreens were analyzed in terms of mineralogy and TiO₂ concentration. The residues formed after aging were characterized in size, shape, chemistry and surface properties. The results showed that a significant fraction of nano-TiO₂ residues was released from all sunscreens, despite their heterogeneous behaviors. A stable dispersion of submicronic aggregates of nanoparticles was generated, representing up to 38w/w% of the amount of sunscreen, and containing up to 30% of the total nano-TiO₂ initially present in the creams. The stability of the dispersion was tested as a function of salt concentration, revealing that in seawater conditions, a major part of these nano-TiO₂ residues will aggregate and sediment. These results were put in perspective with consumption and life cycle of sunscreens to estimate the amount of nano-TiO₂ potentially released into AQUATIC environment.
显示更多 [+] 显示较少 [-]TiO2-based nanoparticles released in water from commercialized sunscreens in a life-cycle perspective: Structures and quantities 全文
2011
Botta, Céline | Labille, Jérôme | Auffan, Melanie | Borschneck, Daniel | Miche, Helene | Cabié, Martiane | Masion, Armand | Rose, Jérôme | Bottero, Jean-Yves | Centre Européen de Recherche et d'Enseignement des Géosciences de l'Environnement (CEREGE) ; Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS) | Spectropôle - Aix Marseille Université (AMU SPEC) ; Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)
International audience | This work investigates the physical-chemical evolution during artificial aging in water of four commercialized sunscreens containing TiO2-based nanocomposites. Sunscreens were analyzed in terms of mineralogy and TiO2 concentration. The residues formed after aging were characterized in size, shape, chemistry and surface properties. The results showed that a significant fraction of nano-TiO2 residues was released from all sunscreens, despite their heterogeneous behaviors. A stable dispersion of submicronic aggregates of nanoparticles was generated, representing up to 38 w/w% of the amount of sunscreen, and containing up to 30% of the total nano-TiO2 initially present in the creams. The stability of the dispersion was tested as a function of salt concentration, revealing that in seawater conditions, a major part of these nano-TiO2 residues will aggregate and sediment. These results were put in perspective with consumption and life cycle of sunscreens to estimate the amount of nano-TiO2 potentially released into AQUATIC environment. (C) 2011 Elsevier Ltd. All rights reserved.
显示更多 [+] 显示较少 [-]Molecular effects and bioaccumulation of levonorgestrel in the non-target organism Dreissena polymorpha 全文
2011
Contardo-Jara, Valeska | Lorenz, Claudia | Pflugmacher, Stephan | Nützmann, Gunnar | Kloas, Werner | Wiegand, Claudia
Molecular effects and bioaccumulation of levonorgestrel in the non-target organism Dreissena polymorpha 全文
2011
Contardo-Jara, Valeska | Lorenz, Claudia | Pflugmacher, Stephan | Nützmann, Gunnar | Kloas, Werner | Wiegand, Claudia
Bioaccumulation and effects of the contraceptive hormone levonorgestrel were examined in the non-target organism Dreissena polymorpha. Molecular biomarkers of biotransformation, elimination, antioxidant defence and protein damage were analyzed after exposure to increasing concentrations of levonorgestrel in a flow-through system. The lowest concentration (0.312 μg L⁻¹) was 100-fold bioconcentrated within four days. A decrease of the bioconcentration factor was observed within one week for the highest test concentrations (3.12 and 6.24 μg L⁻¹) suggesting enhanced excretory processes. The immediate mRNA up-regulation of pi class glutathione S-transferase proved that phase II biotransformation processes were induced. Disturbance of fundamental cell functions was assumed since the aryl hydrocarbon receptor has been permanently down-regulated. mRNA up-regulation of P-glycoprotein, superoxide dismutase and metallothioneine suggested enhanced elimination processes and ongoing oxidative stress. mRNA up-regulation of heat shock protein 70 in mussels exposed to the two highest concentrations clearly indicated impacts on protein damage.
显示更多 [+] 显示较少 [-]Molecular effects and bioaccumulation of levonorgestrel in the non-target organism Dreissena polymorpha 全文
2011
Contardo-Jara, Valeska | Lorenz, Claudia | Pflugmacher, Stephan | Nutzmann, Gunnar | Kloas, Werner | Wiegand, Claudia | Department of Ecophysiology and Aquaculture [Berlin] ; Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB) | Ecohydrology, Leibniz Berlin ; Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB) | Ecosystèmes, biodiversité, évolution [Rennes] (ECOBIO) ; Université de Rennes (UR)-Institut Ecologie et Environnement - CNRS Ecologie et Environnement (INEE-CNRS) ; Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des sciences de l'environnement de Rennes (OSERen) ; Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | University of Southern Denmark (SDU)
International audience | Bioaccumulation and effects of the contraceptive hormone levonorgestrel were examined in the nontarget organism Dreissena polymorpha. Molecular biomarkers of biotransformation, elimination, antioxidant defence and protein damage were analyzed after exposure to increasing concentrations of levonorgestrel in a flow-through system. The lowest concentration (0.312 mg L-1) was 100-fold bioconcentrated within four days. A decrease of the bioconcentration factor was observed within one week for the highest test concentrations (3.12 and 6.24 mg L-1) suggesting enhanced excretory processes. The immediate mRNA up-regulation of pi class glutathione S-transferase proved that phase II biotransformation processes were induced. Disturbance of fundamental cell functions was assumed since the aryl hydrocarbon receptor has been permanently down-regulated. mRNA up-regulation of P-glycoprotein, superoxide dismutase and metallothioneine suggested enhanced elimination processes and ongoing oxidative stress. mRNA up-regulation of heat shock protein 70 in mussels exposed to the two highest concentrations clearly indicated impacts on protein damage.
显示更多 [+] 显示较少 [-]Open Air Laboratories (OPAL): A community-driven research programme 全文
2011
Davies, L. | Bell, J.N.B. | Bone, J. | Creagh-Henry, M. (May) | Hill, L. | Howard, C. | Hobbs, S.J. | Jones, D.T. | Power, S.A. | Rose, N. | Ryder, C. | Seed, L. | Stevens, G. | Toumi, R. | Voulvoulis, N. | White, P.C.L.
Open Air Laboratories (OPAL): A community-driven research programme 全文
2011
Davies, L. | Bell, J.N.B. | Bone, J. | Creagh-Henry, M. (May) | Hill, L. | Howard, C. | Hobbs, S.J. | Jones, D.T. | Power, S.A. | Rose, N. | Ryder, C. | Seed, L. | Stevens, G. | Toumi, R. | Voulvoulis, N. | White, P.C.L.
OPAL is an English national programme that takes scientists into the community to investigate environmental issues. Biological monitoring plays a pivotal role covering topics of: i) soil and earthworms; ii) air, lichens and tar spot on sycamore; iii) water and aquatic invertebrates; iv) biodiversity and hedgerows; v) climate, clouds and thermal comfort. Each survey has been developed by an inter-disciplinary team and tested by voluntary, statutory and community sectors. Data are submitted via the web and instantly mapped. Preliminary results are presented, together with a discussion on data quality and uncertainty. Communities also investigate local pollution issues, ranging from nitrogen deposition on heathlands to traffic emissions on roadside vegetation. Over 200,000 people have participated so far, including over 1000 schools and 1000 voluntary groups. Benefits include a substantial, growing database on biodiversity and habitat condition, much from previously unsampled sites particularly in urban areas, and a more engaged public.
显示更多 [+] 显示较少 [-]Open Air Laboratories (OPAL): a community-driven research programme 全文
2011
Davies, Linda | Bell, J. N. B. | Bone, J. | Head, M. | Hill, L. | Howard, C. | Hobbs, S. J. | Jones, D. T. | Power, S. A. | Rose, N. | Ryder, Claire | Seed, L. | Stevens, G. | Toumi, R. | Voulvoulis, N. | White, P. C. L.
OPAL is an English national programme that takes scientists into the community to investigate environmental issues. Biological monitoring plays a pivotal role covering topics of: i) soil and earthworms; ii) air, lichens and tar spot on sycamore; iii) water and aquatic invertebrates; iv) biodiversity and hedgerows; v) climate, clouds and thermal comfort. Each survey has been developed by an interdisciplinary team and tested by voluntary, statutory and community sectors. Data are submitted via the web and instantly mapped. Preliminary results are presented, together with a discussion on data quality and uncertainty. Communities also investigate local pollution issues, ranging from nitrogen deposition on heathlands to traffic emissions on roadside vegetation. Over 200,000 people have participated so far, including over 1000 schools and 1000 voluntary groups. Benefits include a substantial, growing database on biodiversity and habitat condition, much from previously unsampled sites particularly in urban areas, and a more engaged public.
显示更多 [+] 显示较少 [-]Impact of atmospheric deposition of anthropogenic and natural trace metals on Northwestern Mediterranean surface waters: A box model assessment 全文
2011
Heimbürger, Lars-Eric | Migon, Christophe | Cossa, Daniel
Impact of atmospheric deposition of anthropogenic and natural trace metals on Northwestern Mediterranean surface waters: A box model assessment 全文
2011
Heimbürger, Lars-Eric | Migon, Christophe | Cossa, Daniel
Under stratified oligotrophic conditions (May–November), the surface mixed layer of the Northwestern Mediterranean constitutes a homogeneous water volume of 10–30m depth. In other respects, the mean residence time of Ligurian surface waters (0–200m) is 102 days. It is therefore possible to quantify the extent to which atmospheric deposition of trace metals affects surface waters. On the basis of literature data on anthropogenic and natural trace metals, we demonstrate that the ratios between total seawater labile atmospheric deposition during 102 days (Δc) and dissolved TM concentrations in Ligurian surface waters (c) illustrate the impact of atmospheric deposition on surface seawater (Δc/c). High ratios indicate surface TM enrichments, while low ratios indicate surface TM depletion, due to the quasi-complete sorption and removal of TMs by plankton during spring bloom. The simple box model proposed here may be used for other marine regions where hydrodynamical and physico-chemical constraints are well defined.
显示更多 [+] 显示较少 [-]Impact of atmospheric deposition of anthropogenic and natural trace metals on Northwestern Mediterranean surface waters: A box model assessment 全文
2011
Heimbuerger, Lars-eric | Migon, Christophe | Cossa, Daniel
Under stratified oligotrophic conditions (May November), the surface mixed layer of the Northwestern Mediterranean constitutes a homogeneous water volume of 10-30 m depth. In other respects, the mean residence time of Ligurian surface waters (0-200 m) is 102 days. It is therefore possible to quantify the extent to which atmospheric deposition of trace metals affects surface waters. On the basis of literature data on anthropogenic and natural trace metals, we demonstrate that the ratios between total seawater labile atmospheric deposition during 102 days (Delta c) and dissolved TM concentrations in Ligurian surface waters (c) illustrate the impact of atmospheric deposition on surface seawater (Delta c/c). High ratios indicate surface TM enrichments, while low ratios indicate surface TM depletion, due to the quasi-complete sorption and removal of TMs by plankton during spring bloom. The simple box model proposed here may be used for other marine regions where hydrodynamical and physico-chemical constraints are well defined. (C) 2011 Elsevier Ltd. All rights reserved.
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