خيارات البحث
النتائج 2501 - 2510 من 2,512
Molecular biomarkers in grey seals (Halichoerus grypus) to evaluate pollutant exposure, health and immune status النص الكامل
2014
Lehnert, Kristina | Müller, Sabine | Weirup, Lina | Ronnenberg, Katrin | Pawliczka vel Pawlik, Iwona Joanna | Rosenberger, Tanja | Siebert, Ursula
Molecular biomarkers in grey seals (Halichoerus grypus) to evaluate pollutant exposure, health and immune status النص الكامل
2014
Lehnert, Kristina | Müller, Sabine | Weirup, Lina | Ronnenberg, Katrin | Pawliczka vel Pawlik, Iwona Joanna | Rosenberger, Tanja | Siebert, Ursula
Grey seals as top-predators bioaccumulate contaminants and can be considered as sentinels of ecosystem health. Pups are weaned after a short nursing period, characterised by an enormous lipid transfer and exposure to contaminants. This study established molecular biomarkers of the xenobiotic metabolism and immune system to help assess health and immune status. mRNA transcription of AHR, ARNT, PPAR~a and cytokine IL-2 and heat-shock-protein HSP70 was measured in blood of grey seal pups and adults in rehabilitation and permanent care using RT-qPCR and compared to rehabilitating harbour seal pups and haematology values. In pups highest levels at admission in xenobiotic biomarker, HSP70 and cytokine transcription may show contaminant exposure via lactation, stress during abandonment and dehydration. The significant decrease may be linked to diet, health improvement and adaptation. Adults showed higher levels and more variation in biomarker transcription and clear species-specific differences between harbour and grey seal pups were found.
اظهر المزيد [+] اقل [-]Molecular biomarkers in grey seals (Halichoerus grypus) to evaluate pollutant exposure, health and immune status النص الكامل
2014
Lehnert, K. | Muller, S. | Weirup, L. | Ronnenberg, K. | Pawliczka, I. | Rosenberger, T. | Siebert, U.
Grey seals as top-predators bioaccumulate contaminants and can be considered as sentinels of eco-system health. Pups are weaned after a short nursing period, characterised by an enormous lipid transfer and exposure to contaminants. This study established molecular biomarkers of the xenobiotic metabolism and immune system to help assess health and immune status. mRNA transcription of AHR, ARNT, PPARα and cytokine IL-2 and heat-shock-protein HSP70 was measured in blood of grey seal pups and adults in rehabilitation and permanent care using RT-qPCR and compared to rehabilitating harbour seal pups and haematology values. In pups highest levels at admission in xenobiotic biomarker, HSP70 and cytokine transcription may show contaminant exposure via lactation, stress during abandonment and dehydration. The significant decrease may be linked to diet, health improvement and adaptation. Adults showed higher levels and more variation in biomarker transcription and clear species-specific differences between harbour and grey seal pups were found.
اظهر المزيد [+] اقل [-]Effects evaluation and risk assessment of air pollutants deposition at European monitoring sites of the ICP forests النص الكامل
2014
Fischer, Richard | Scheuschner, Thomas | Schlutow, Angela | Granke, Oliver | Mues, Volker | Olschofsky, Konstantin | Nagel, H.-D.
Modelling climate change impact on European crop and livestock systems النص الكامل
2014
Carozzi, Marco | Massad, Raia Silvia | Martin, Raphaël | Shtiliyanova, Anastasiya | Klumpp, Katja | Drouet, Jean-Louis
Modelling climate change impact on European crop and livestock systems النص الكامل
2014
Carozzi, Marco | Massad, Raia Silvia | Martin, Raphaël | Shtiliyanova, Anastasiya | Klumpp, Katja | Drouet, Jean-Louis
Modelling climate change impact on European crop and livestock systems النص الكامل
2014
Carozzi, Marco | Massad, Raia Silvia | Martin, Raphaël | Shtiliyanova, Anastasiya | Klumpp, Katja | Drouet, Jean-Louis
Detection of temporal trends in atmospheric deposition of inorganic nitrogen and sulphate to forests in Europe النص الكامل
2014
Waldner, Peter | Marchetto, Aldo | Thimonier, Anne | Schmitt, Maria | Rogora, Michela | Granke, Oliver | Mues, Volker | Hansen, Karin | Pihl-Karlsson, Gunilla | Zlindra, Daniel | Clarke, Nicholas | Verstraeten, Arne | Lazdins, Andis | Schimming, Claus | Iacoban, Carmen | Lindroos, Antti-Jussi | Vanguelova, Elena I. | Fischer, Uwe | Seidling, Walter | Fischer, Richard
Detection of temporal trends in atmospheric deposition of inorganic nitrogen and sulphate to forests in Europe النص الكامل
2014
Waldner, Peter | Marchetto, Aldo | Thimonier, Anne | Schmitt, Maria | Rogora, Michela | Granke, Oliver | Mues, Volker | Hansen, Karin | Pihl-Karlsson, Gunilla | Zlindra, Daniel | Clarke, Nicholas | Verstraeten, Arne | Lazdins, Andis | Schimming, Claus | Iacoban, Carmen | Lindroos, Antti-Jussi | Vanguelova, Elena I. | Fischer, Uwe | Seidling, Walter | Fischer, Richard
Atmospheric deposition to forests has been monitored within the International Cooperative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests) with sampling and analyses of bulk precipitation and throughfall at several hundred forested plots for more than 15 years. The current deposition of inorganic nitrogen (nitrate and ammonium) and sulphate is highest in central Europe as well as in some southern regions. We compared linear regression and Manne-Kendall trend analysis techniques often used to detect temporal trends in atmospheric deposition. The choice of method influenced the number of significant trends. Detection of trends was more powerful using monthly data compared to annual data. The slope of a trend needed to exceed a certain minimum in order to be detected despite the short-term variability of deposition. This variability could to a large extent be explained by meteorological processes, and the minimum slope of detectable trends was thus similar across sites and many ions. The overall decreasing trends for inorganic nitrogen and sulphate in the decade to 2010 were about 2% and 6%, respectively. Time series of about 10 and 6 years were required to detect significant trends in inorganic nitrogen and sulphate on a single plot. The strongest decreasing trends were observed in western central Europe in regions with relatively high deposition fluxes, whereas stable or slightly increasing deposition during the last 5 years was found east of the Alpine region as well as in northern Europe. Past reductions in anthropogenic emissions of both acidifying and eutrophying compounds can be confirmed due to the availability of long-term data series but further reductions are required to reduce deposition to European forests to levels below which significant harmful effects do not occur according to present knowledge.
اظهر المزيد [+] اقل [-]Detection of temporal trends in atmospheric deposition of inorganic nitrogen and sulphate to forests in Europe النص الكامل
2014
Waldner, Peter et al. | Metsäntutkimuslaitos
Detection of temporal trends in atmospheric deposition of inorganic nitrogen and sulphate to forests in Europe النص الكامل
2014
Waldner, Peter | Marchetto, Aldo | Thimonier, Anne | Schmitt, Maria | Rogora, Michela | Granke, Oliver | Mues, Volker | Hansen, Karin | Pihl Karlsson, Gunilla | Žlindra, Daniel | Clarke, Nicholas | Verstraeten, Arne | Lazdins, Andis | Schimming, Claus | Iacoban, Carmen | Lindroos, Antti-Jussi | Vanguelova, E. (Elena) | Benham, Sue | Meesenburg, Henning | Nicolas, Manuel | Kowalska, Anna | Apuhtin, Vladislav | Napa, Ulle | Lachmanová, Zora | Kristoefel, Ferdinand | Bleeker, Albert | Ingerslev, Morten | Vesterdal, Lars | Molina, Juan | Fischer, Uwe | Seidling, Walter | Jonard, Mathieu | O'Dea, Philip | Johnson, James | Fischer, Richard | Lorenz, Martin
Atmospheric deposition to forests has been monitored within the International Cooperative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests) with sampling and analyses of bulk precipitation and throughfall at several hundred forested plots for more than 15 years. The current deposition of inorganic nitrogen (nitrate and ammonium) and sulphate is highest in central Europe as well as in some southern regions. We compared linear regression and Mann–Kendall trend analysis techniques often used to detect temporal trends in atmospheric deposition. The choice of method influenced the number of significant trends. Detection of trends was more powerful using monthly data compared to annual data. The slope of a trend needed to exceed a certain minimum in order to be detected despite the short-term variability of deposition. This variability could to a large extent be explained by meteorological processes, and the minimum slope of detectable trends was thus similar across sites and many ions. The overall decreasing trends for inorganic nitrogen and sulphate in the decade to 2010 were about 2% and 6%, respectively. Time series of about 10 and 6 years were required to detect significant trends in inorganic nitrogen and sulphate on a single plot. The strongest decreasing trends were observed in western central Europe in regions with relatively high deposition fluxes, whereas stable or slightly increasing deposition during the last 5 years was found east of the Alpine region as well as in northern Europe. Past reductions in anthropogenic emissions of both acidifying and eutrophying compounds can be confirmed due to the availability of long-term data series but further reductions are required to reduce deposition to European forests to levels below which significant harmful effects do not occur according to present knowledge.
اظهر المزيد [+] اقل [-]Spatial variation of deposition in Europe النص الكامل
2014
Fischer, Uwe | Seidling, Walter
Tree crown condition and damage causes النص الكامل
2014
Wellbrock, Nicole | Eickenscheidt, Nadine | Haelbich, Henny
Tree crown condition and damage causes النص الكامل
2014
Becher, Georg | Lorenz, Martin | Haelbich, Henny | Mues, Volker
Sulphate and nitrogen deposition to forests and trend analyses النص الكامل
2014
Becher, Georg | Waldner, Peter | Hansen, Karin | Fischer, Richard | Lorenz, Martin | Seidling, Walter
Determination of atmospheric nitrogen deposition to a semi-natural peat bog site in an intensively managed agricultural landscape النص الكامل
2014
Hurkuck, Miriam | Brümmer, Christian | Mohr, Karsten | Grünhage, Ludger | Flessa, Heinz | Kutsch, Werner Leo
Determination of atmospheric nitrogen deposition to a semi-natural peat bog site in an intensively managed agricultural landscape النص الكامل
2014
Hurkuck, Miriam | Brümmer, Christian | Mohr, Karsten | Grünhage, Ludger | Flessa, Heinz | Kutsch, Werner Leo
Rising levels of atmospheric nitrogen (N) deposition have been found to affect the primary productivity and species composition of most terrestrial ecosystems. Highly vulnerable ecosystems such as nutrientpoor bogs are expected to respond to increasing N input rates with a decrease in plant species diversity. Our study site e a moderately drained raised bog and one of only very few remaining protected peatland areas in Northwestern Germany e is surrounded by highly fertilised agricultural land and intensive livestock production. We quantified the annual deposition of atmospheric N over a period of two years. Dry deposition rates of different N species and their reactants were calculated from day and night-time concentrations measured by a KAPS denuder filter system. Dry N deposition amounted to 10.9 ± 1.0 kg N ha-1 yr-1 (year 1) and 10.5 ± 1.0 kg N ha-1 yr-1 (year 2). More than 80% of total deposited N was attributed to ammonia (NH3). A strong seasonality in NH3 concentrations and depositions could be observed. Day and night-time concentrations and depositions, however, did not differ significantly. Total N deposition including bulk N deposition resulted in about 25 kg N ha-1 yr-1. Our results suggest that the intensive agricultural land management of surrounding areas and strongly emitting animal husbandry lead to N inputs into the protected peatland area that exceed the ecosystem's specific critical load up to fivefold. This gives rise to the assumption that a further shift in plant species composition with a subsequent alteration of the local hydrological regime can be expected
اظهر المزيد [+] اقل [-]Determination of atmospheric nitrogen deposition to a semi-natural peat bog site in an intensively managed agricultural landscape النص الكامل
2014
Hurkuck, Miriam | Brümmer, Christian | Mohr, Karsten | Grünhage, Ludger | Flessa, Heinz | Kutsch, Werner L.
Rising levels of atmospheric nitrogen (N) deposition have been found to affect the primary productivity and species composition of most terrestrial ecosystems. Highly vulnerable ecosystems such as nutrient-poor bogs are expected to respond to increasing N input rates with a decrease in plant species diversity. Our study site – a moderately drained raised bog and one of only very few remaining protected peatland areas in Northwestern Germany – is surrounded by highly fertilised agricultural land and intensive livestock production. We quantified the annual deposition of atmospheric N over a period of two years. Dry deposition rates of different N species and their reactants were calculated from day and night-time concentrations measured by a KAPS denuder filter system. Dry N deposition amounted to 10.9 ± 1.0 kg N ha−1 yr−1 (year 1) and 10.5 ± 1.0 kg N ha−1 yr−1 (year 2). More than 80% of total deposited N was attributed to ammonia (NH3). A strong seasonality in NH3 concentrations and depositions could be observed. Day and night-time concentrations and depositions, however, did not differ significantly. Total N deposition including bulk N deposition resulted in about 25 kg N ha−1 yr−1. Our results suggest that the intensive agricultural land management of surrounding areas and strongly emitting animal husbandry lead to N inputs into the protected peatland area that exceed the ecosystem's specific critical load up to fivefold. This gives rise to the assumption that a further shift in plant species composition with a subsequent alteration of the local hydrological regime can be expected.
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