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Accumulation of mercury and methylmercury by mushrooms and earthworms
2011
Rieder, Stephan | Brunner, Ivano Livio | Horvat, Milena | Jacobs, Anna | Frey, Beat
Accumulation of total and methyl-Hg by mushrooms and earthworms was studied in thirty-four natural forest soils strongly varying in soil physico-chemical characteristics. Tissue Hg concentrations of both receptors did hardly correlate with Hg concentrations in soil. Both total and methyl-Hg concentrations in tissues were species-specific and dependent on the ecological groups of receptor. Methyl-Hg was low accounting for less than 5 and 8% of total Hg in tissues of mushrooms and earthworms, respectively, but with four times higher concentrations in earthworms than mushrooms. Total Hg concentrations in mushrooms averaged 0.96 mg Hg/kg dw whereas litter decomposing mushrooms showed highest total Hg and methyl-Hg concentrations. Earthworms contained similar Hg concentrations (1.04 mg Hg/kg dw) whereas endogeic earthworms accumulated highest amounts of Hg and methyl-Hg.
Показать больше [+] Меньше [-]Mechanisms of purple moor-grass (Molinia caerulea) encroachment in dry heathland ecosystems with chronic nitrogen inputs
2011
Friedrich, Uta | Oheimb, Goddert von | Dziedek, Christoph | Kriebitzsch, Wolf-Ulrich | Selbmann, Katharina | Härdtle, Werner
Optimal emission policy under the risk of irreversible pollution
2011
Ayong Le Kama, Alain | Pommeret, Aude | Prieur, Fabien
We consider an optimal consumption and pollution problem that has two important features. Environmental damages due to economic activities may be irreversible and the level at which the degradation becomes irreversible is unknown. Particular attention is paid to the situation where agents are relatively impatient and/or do not care a lot about the environment and/or Nature regenerates at low rate. We show that the optimal policy of the uncertain problem drives the economy in the long run toward a steady state while, when ignoring irreversibility, the economy follows a balanced growth path accompanied by a perpetual decrease in environmental quality and consumption, both asymptotically converging toward zero. Therefore, accounting for the risk of irreversibility induces more conservative decisions regarding consumption and polluting emissions. In general, however, we cannot rule out situations where the economy will optimally follow an irreversible path and consequently, will also be left, in the long run, with an irreversibly degraded environment.
Показать больше [+] Меньше [-]Concentrations of metals and POPs in liver tissue of wild sea bird chicks from the Norwegian arctic region
2011
Hegseth, Marit Nøst | Regoli, Francesco | Gorbi, Stefania | Bocchetti, Raffaella | Gabrielsen, Geir W | Camus, Lionel
Lysosomal membrane stability, lipofuscin (LF), malondialdehyde (MDA), neutral lipid (NL) levels, as well as halogenated organic compounds (HOCs), Cr, Cd, Pb and Fe concentrations were analyzed in liver of black-legged kittiwake (BK), herring gull (HG), and northern fulmar (NF) chicks. There were significant species differences in the levels of NL, LF and lysosomal membrane stability. These parameters were not associated with the respective HOC concentrations. LF accumulation was associated with increasing Cr, Cd and Pb concentrations. HG presented the lowest lysosomal membrane stability and the highest. LF and NL levels, which indicated impaired lysosomes in HG compared to NF and BK. Lipid peroxidation was associated with HOC and Fe2+ levels. Specific HOCs showed positive and significant correlations with MDA levels in HG. The study indicates that contaminant exposure can affect lysosomal and lipid associated parameters in seabird chicks even at low exposure levels. These parameters may be suitable markers of contaminant induced stress in arctic seabirds.
Показать больше [+] Меньше [-]Lanscape control on diffuse pollution : a critical review on some investigations on phosphorus – retaining landscape features
2011
Dorioz, Jean Marcel | Gascuel-Odoux, Chantal | Merot, Philippe | Trevisan, Dominique
This text focuses on the identification, efficiencies, classification and management of landscape features having a potential buffer function regarding diffuse phosphorus, because of their specific structure (vegetation-soil) and of their location at the interface between sources (farm infrastructures, emitting fields…) and surface water bodies. These buffers are very diverse and correspond to natural landscape features (wetlands, riparian areas…) as well as manmade structures (constructed buffer strips or intermediate cases such as field margins, hedgerows). Their role and efficiency depends on the local factors controlling the retention processes (internal organisation and properties of the buffer), on the position within the watershed, and on the landscape context which reciprocally determines the overall buffer capacity of a watershed. On that basis, we recognize the diversity of the buffers in structure and functioning and thus in the way they attenuate the signal, their limitations (sustainability, side effects) and their hierarchic organisation at the watershed scale.
Показать больше [+] Меньше [-]Is a little pollution good for you?
2011
Elliott, Kevin Christopher
"Could low-level exposure to polluting chemicals be analogous to exercise-a beneficial source of stress that strengthens the body? Some scientists studying the phenomenon of hormesis (beneficial or stimulatory effects caused by low-dose exposure to toxic substances) claim that that this may be the case. IS A LITTLE POLLUTION GOOD FOR YOU? critically examines the current evidence for hormesis. In the process, it highlights the range of methodological and interpretive judgments involved in environmental research: choices about what questions to ask and how to study them, decisions about how to categorize and describe new information, judgments about how to interpret and evaluate ambiguous evidence, and questions about how to formulate public policy in response to debated scientific findings. The book also uncovers the ways that interest groups with deep pockets attempt to influence these scientific judgments for their benefit. Several chapters suggest ways to counter these influences and incorporate a broader array of societal values in environmental research: (1) moving beyond conflict-of-interest policies to develop new ways of safeguarding academic research from potential biases; (2) creating deliberative forums in which multiple stakeholders can discuss the judgments involved in policy-relevant research; and (3) developing ethical guidelines that can assist scientific experts in disseminating debated and controversial phenomena to the public. Kevin C. Elliott illustrates these strategies in the hormesis case, as well as in two additional case studies involving contemporary environmental research: endocrine disruption and multiple chemical sensitivity. This book should be of interest to a wide variety of readers, including scientists, philosophers, policy makers, environmental ethicists and activists, research ethicists, industry leaders, and concerned citizens."--Pub. desc.
Показать больше [+] Меньше [-]Concentrations of persistant organic pollutants in Great skua eggs (Stercorarius skua) from Shetland 1980 and 2008
2011
Leat, Eliza HK | Bourgeon, Sophie | Borgå, Katrine | Strøm, Hallvard | Hanssen, Sveinn Are | Gabrielsen, Geir W | Petersen, Ævar | Olafsdottir, Kristin | Magnusdottir, Ellen | Fisk, Aaron T | Ellis, Sandra | Bustnes, Jan Ove | Furness, Robert W
Concentrations of POPs in Great skua eggs from Shetland are among the highest in North Atlantic seabirds, with up to 11,600 µg/kg (ww) DDE and up to 17,900 µg/kg ww SumPCB. Concentrations of legacy POPs were significantly lower in 2008 than 1980. Decreases were greatest for least persistent compounds. Median SumPBDEs increased from 99 µg/kg ww in 1980 to 173 µg/kg ww in 2008. There were changes in Great skua breeding season diet, with more adult Herring and Mackerel and less Sandeel. These changes increase exposure to POPs, since Herring and Mackerel accumulate more POPs than Sandeels. In both years, eggs with higher d15N had higher POP concentrations. In 1980, birds feeding more on demersal discard fish from trawl fisheries and less on Sandeels, had higher POP levels in eggs. In 2008, individuals feeding more on Herring and Mackerel, and less on discards, had higher POP levels in eggs.
Показать больше [+] Меньше [-]Introduction
2011
Mills, Gina | Harmens, Harry | Vandermeiren, Karine | Bender, Jürgen
Evaluation of the ozone-related risk for wheat at the local scale
2011
Grünhage, Ludger | Bender, Jürgen | Jäger, Hans-Jürgen | Matyssek, Rainer | Weigel, Hans-Joachim