خيارات البحث
النتائج 1 - 10 من 22
L' etat des forets en Europe.
1994
Haemmerli F. | Vogel J. | Volz R.
Silver fir decline in the Vosges mountains (France): role of climate and silviculture.
1989
Becker M. | Landmann G. | Levy G.
UV-irradiation and leaching in water reduce the toxicity of imidacloprid-contaminated leaves to the aquatic leaf-shredding amphipod Gammarus fossarum
2018
Englert, Dominic | Zubrod, Jochen P. | Neubauer, Christoph | Schulz, Ralf | Bundschuh, Mirco
Systemic neonicotinoid insecticides such as imidacloprid are increasingly applied against insect pest infestations on forest trees. However, leaves falling from treated trees may reach nearby surface waters and potentially represent a neonicotinoid exposure source for aquatic invertebrates. Given imidacloprid's susceptibility towards photolysis and high water solubility, it was hypothesized that the leaves' toxicity might be modulated by UV-irradiation during decay on the forest floor, or by leaching and re-mobilization of the insecticide from leaves within the aquatic ecosystem. To test these hypotheses, the amphipod shredder Gammarus fossarum was fed (over 7 d; n = 30) with imidacloprid-contaminated black alder (Alnus glutinosa) leaves that had either been pre-treated (i.e., leached) in water for up to 7 d or UV-irradiated for 1 d (at intensities relevant during autumn in Central Europe) followed by a leaching duration of 1 d. Gammarids' feeding rate, serving as sublethal response variable, was reduced by up to 80% when consuming non-pretreated imidacloprid-contaminated leaves compared to imidacloprid-free leaves. Moreover, both leaching of imidacloprid from leaves (for 7 d) as well as UV-irradiation reduced the leaves' imidacloprid load (by 46 and 90%) thereby mitigating the effects on gammarids' feeding rate to levels comparable to the respective imidacloprid-free controls. Therefore, natural processes, such as UV-irradiation and re-mobilization of foliar insecticide residues in water, might be considered when evaluating the risks systemic insecticide applications in forests might pose for aquatic organisms in nearby streams.
اظهر المزيد [+] اقل [-][State of forests in Europe]
1994
Haemmerli, F. | Vogel, J. | Volz, R.
Simulation of effects of atmospheric ethylene on tree leaf shedding
1989
Sawada, S. | Hazama, Y. | Hayakawa, T. (Department of Biology, Faculty of Science, Hirosaki University, Hirosaki 036 (Japan))
The state of transboundary air pollution: 1992 update. Report prepared within the framework of the Convention on Long-Range Transboundary Air Pollution
1993
The state of transboundary air pollution: 1989 update
1990
Nutrient stress in young Scots pines suffering from needle loss in a dry heath forest
1990
Tikkanen, E. (Lapland Univ., Rovaniemi (Finland). Arctic Centre) | Raitio, H.
The state of transboundary air pollution: 1989 update. Report prepared within the framework of the Convention on Long-Range Transboundary Air Pollution.
1990
[The state of transboundary air pollution: 1992 update]
1993
