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Changes in pigment concentration and composition in Norway spruce induced by long-term exposure to low levels of ozone.
1995
Mikkelsen T.N. | Dodell B. | Lutz C.
Phytol as a possible indicator of ozone stress by Picea abies.
1995
Ekeberg D. | Jablonska A.M. | Ogner G.
Tuna and dolphin associations in the Northeast Atlantic: Evidence of different ecological niches from stable isotope and heavy metal measurements
2000
Das, Krishna | Lepoint, Gilles | Loizeau, Véronique | Debacker, Virginie | Dauby, Patrick | Bouquegneau, Jean-Marie
peer reviewed | Associations of tunas and dolphins in the wild are quite frequent events and the question arises how predators requiring similar diet in the same habitat share their environmental resources. As isotopic composition of an animal is related to that of its preys, stable isotopes (13C/12C and 15N/14N) analyses were performed in three predator species from the Northeast Atlantic: the striped dolphin, Stenella coeruleoalba, the common dolphin Delphinus delphis, and the albacore tuna, Thunnus alalunga, and compared to their previously described stomach content. Heavy metals (Cd, Zn, Cu and Fe) are mainly transferred through the diet and so, have been determined in the tissues of the animals. Tunas muscles display higher delta15N than in common and striped dolphins (mean: 11.4 0/00 vs. 10.3 0/00 and 10.4 0/00, respectively) which reflects its higher trophic level nutrition. Higher delta13C are found in common (-18.4 0/00) and striped dolphin (-18.10/00) muscles than in albacore tuna (-19.3 0/00) likely in relation with its migratory pattern. The most striking feature is the presence of two levels of cadmium concentrations in the livers of the tunas (32 mg kg-1 dry weight vs. 5 mg kg-1 dry weight). These two groups also differ by their iron concentrations and their delta15N and delta 13C liver values. These results suggest that in the Biscay Bay, tunas occupy two different ecological niches likely based on different squid input in their diet.
Afficher plus [+] Moins [-]Determination of organohalogenated contaminants in liver of harbour porpoises (Phocoena phocoena) stranded on the Belgian North Sea coast
2002
Covaci, Adrian | Van de Vijver, Kristin Inneke | De Coen, Wim | Das, Krishna | Bouquegneau, Jean-Marie | Blust, Ronny | Schepens, Paul | MARE - Centre Interfacultaire de Recherches en Océanologie - ULiège
peer reviewed
Afficher plus [+] Moins [-]Baseline study of perfluorochemicals in harbour porpoises (Phocoena phocoena) from Northern Europe
2004
Van de Vijver, Kristin Inneke | Hoff, P. T. | Das, Krishna | Van Dongen, Walter | Esmans, Eddy Louis | Siebert, Ursula | Bouquegneau, Jean-Marie | Blust, Ronny | De Coen, Wim | MARE - Centre Interfacultaire de Recherches en Océanologie - ULiège
peer reviewed | Marie-Curie Fellowship
Afficher plus [+] Moins [-]Acid-sensitive waters of the English Lake District: a steady-state model of streamwater chemistry in the upper Duddon catchment
1989
Tipping, E. (Inst. Freshwater Ecology, Windermere Lab., Ambleside, Cumbria LA22 0LP (UK))
Effects of simulated acid rain and ozone on foliar chemistry of field-grown Pinus ponderosa seedlings and mature trees
1996
Momen, B. | Helms, J.A. (Department of Environmental Science, University of California, Berkeley, California 94720 (USA))
An investigation of the impact of afforestation on stream-water chemistry in the Loch Dee catchment, SW Scotland
1995
Nisbet, T.R. | Fowler, D. | Smith, R.I. (Forestry Authority Division Research, Alice Holt Lodge, Farnham, Surrey, GU10 4LH (United Kingdom))
Change in the dendrochemistry of sacred fir close to Mexico City over the past 100 years
1999
Watmough, S.A. | Hutchinson, T.C. (ERS Program, Trent University, Peterborough, Ontario K9J 7B8 (Canada))
The effect of simulated acid rain on the biochemical composition of Scots pine (Pinus sylvestris L.) needles
1996
Shumejko, P. | Ossipov, V. | Neuvonen, S. (Institute of Forest, Krasnoyarsk, 660036 Akademgorodok (Russian Federation))