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(Table 2) Concentrations of polychlorinated naphthalene congeners in blubber samples from whales, seals and porpoises between 1986-2009
2012
Rotander, Anna | van Bavel, Bert | Rigét, Frank F | Auðunsson, Guðjón Atli | Polder, Anuschka | Gabrielsen, Geir W | Víkingsson, Gísli | Mikkelsen, Bjarni | Dam, Maria
A selection of PCN congeners was analyzed in pooled blubber samples of pilot whale (Globicephala melas), ringed seal (Phoca hispida), minke whale (Balaenoptera acutorostrata), fin whale (Balaenoptera physalus), harbour porpoise (Phocoena phocoena), hooded seal (Cystophora cristata) and Atlantic whitesided dolphin (Lagenorhynchus acutus), covering a time period of more than 20 years (1986-2009). A large geographical area of the North Atlantic and Arctic areas was covered. PCN congeners 48, 52, 53, 66 and 69 were found in the blubber samples between 0.03 and 5.9 ng/g lw. Also PCBs were analyzed in minke whales and fin whales from Iceland and the total PCN content accounted for 0.2% or less of the total non-planar PCB content. No statistically significant trend in contaminant levels could be established for the studied areas. However, in all species except minke whales caught off Norway the lowest Sum PCN concentrations were found in samples from the latest sampling period.
Mostrar más [+] Menos [-]Updated stomatal flux and flux-effect models for wheat for quantifying effects of ozone on grain yield, grain mass and protein yield
2012
Grünhage, Ludger | Pleijel, Hakan | Mills, Gina | Bender, Jürgen | Danielsson, Helena | Lehmann, Yvonne | Castell, Jean-Francois | Bethenod, Olivier
Immunotoxic effects of environmental toxicants in fish - how to assess them?
2012
Segner, H. | Wenger, M. | Möller, A.M.; | Köllner, Bernd | Casanova-Nakayama, A.;
Numerous environmental chemicals, both long-known toxicants such as persistent organic pollutants as well as emerging contaminants such as pharmaceuticals, are known to modulate immune parameters of wildlife species, what can have adverse consequences for the fitness of individuals including their capability to resist pathogen infections. Despite frequent field observations of impaired immunocompetence and increased disease incidence in contaminant-exposed wildlife populations, the potential relevance of immunotoxic effects for the ecological impact of chemicals is rarely considered in ecotoxicological risk assessment. A limiting factor in the assessment of immunotoxic effects might be the complexity of the immune system what makes it difficult (1) to select appropriate exposure and effect parameters out of the many immune parameters which could be measured, and (2) to evaluate the significance of the selected parameters for the overall fitness and immunocompetence of the organism. Here, we present - on the example of teleost fishes - a brief discussion of how to assess chemical impact on the immune system using parameters at different levels of complexity and integration: immune mediators, humoral immune effectors, cellular immune defenses, macroscopical and microscopical responses of lymphoid tissues and organs, and host resistance to pathogens. Importantly, adverse effects of chemicals on immunocompetence may be detectable only after immune system activation, e.g., after pathogen challenge, but not in the resting immune system of non-infected fish. Current limitations to further development and implementation of immunotoxicity assays and parameters in ecotoxicological risk assessment are not primarily due to technological constraints, but are related from insufficient knowledge of (1) possible modes of action in the immune system, (2) the importance of intra- and inter-species immune system variability for the response against chemical stressors, and (3) deficits in conceptual and mechanistic assessment of combination effects of chemicals and pathogens.
Mostrar más [+] Menos [-]Chlordécone aux Antilles : évolution des systèmes de culture et leur incidence sur la dispersion de la pollution
2012
Jannoyer-Lesueur M. | Cattan P. | Monti D. | Saison C. | Voltz M. | Woignier T. | Cabidoche Y.M.
La chlordécone, insecticide organochloré, était utilisée pour lutter contre le charançon du bananier (Cosmopolites sordidus) de 1971 à 1993. La chlordécone est peu mobile et se dégrade à une vitesse très lente, voire nulle dans les sols aérés. Sa persistance est donc longue, et la dépollution artificielle n'est pas opérationnelle actuellement. Cependant les sols restent fertiles même si ils constituent la principale réserve et source de pollution. Il faut donc gérer cette pollution. Cela implique des changements au sein des agrosystèmes, tant sur le choix des productions possibles que sur certaines pratiques agronomiques pour réduire les impacts sanitaires. Pour les espèces cultivées sur les parcelles polluées, certains organes sont très contaminés (tubercules), d'autres indemnes (fruits d'arbres, banane, ananas, tomate, etc.). Un outil de gestion est disponible pour les producteurs afin d'anticiper le choix des cultures et de réduire le risque d'exposition des consommateurs. Réciproquement, les systèmes de culture ont une incidence sur la dispersion de la molécule à l'échelle d'une parcelle et d'un bassin versant. La chlordécone contamine les ressources et les organismes aquatiques via les eaux de percolations issues des parcelles polluées. Cet article fait le point sur les principaux résultats disponibles et les projets en cours sur la gestion des agrosystèmes et les processus de transferts de la chlordécone vers l'environnement ainsi que leurs impacts sur les écosystèmes aquatiques. (Résumé d'auteur)
Mostrar más [+] Menos [-]A review of introduced species in Montenegrian coastal sea | Pregled unešenih vrsta u crnogorskom podmorju
2012
Mačić, V., Institut za biologiju mora, Kotor (Montenegro) | Kljajić, Z., Institut za biologiju mora, Kotor (Montenegro)
Based on all available data a review of introduced non-indigenous species is reported for the area of Montenegrian coastal sea (South-East Adriatic Sea). All together 11 species were recorded, three algae and eight animals. Monitoring of invasive species has been done partially only for Caulerpa racemose var. cylindracea, while for other species distribution and impact on autochthonous environment is unknown.
Mostrar más [+] Menos [-]Influence of wastewater on seawater and sediment quality in the Bokokotorska Bay [Adriatic sea, Montenegro] | Uticaj otpadnih voda na kvalitet morske vode i sedimenta u Bokokotorskom zalivu [Jadransko more, Crna Gora]
2012
Marković, S., Institut za biologiju mora, Kotor (Montenegro) | Kolarević, S., Biološki fakultet, Beograd (Serbia) | Vuković-Gačić, B., Biološki fakultet, Beograd (Serbia) | Kljajić, Z., Institut za biologiju mora, Kotor (Montenegro)
In this paper the results of preliminary investigations of microbiological quality of seawater and sediment are presented. Analyses are performed by membrane filtration. The samples were collected near the sawage outfalls in Bokakotorska bay. It is noticed much higher number of bacteria – indicators of fecal pollution in sediment surface that seawater overlaying the sediment. Concentrations of bacteria diminished in layers of sediment laying deeper that sediment surface. Influence of wastewater is the most evident on 1 and 3 positions.
Mostrar más [+] Menos [-]Dynamic of physico-chemical parameters and chlorophyll a in Boka Kotorska Bay [Adriatic sea, Montenegro] | Dinamika fizičko-hemijskih parametara i hlorofila a u Bokokotorskom zalivu [Jadransko more, Crna Gora]
2012
Žmukić, J., Institut za biologiju mora, Kotor (Montenegro) | Krivokapić, S., Prirodno-matematički fakultet, Podgorica (Montenegro) | Kljajić, Z., Institut za biologiju mora, Kotor (Montenegro)
The fact is that in the world today water and land represents limited life resources which are more and more degrade and disturbed, mostly by anthropogenic influence. Especially water (seas, rivers, lakes) is exposed to various types of pollution. The fact is that in the world today water and land represented limited life resources which are more. That why in present time we conduct numerous scientific researches to examine, advance and protect our environment, especially water as a limited and delicate natural resource. In this work results from April to September 2011 are presented, which comprised analyses of samples from 8 stations in Boka Kotorska Bay. The main aim was to estimate trophic level, of determining the concentration of the physico-chemical parameters, chlorophyll a and TRIX index in Boka Kotorska Bay.
Mostrar más [+] Menos [-]Nitrogen loads of water at littoral part of Lake Prespa [The Former Yugoslav Republic of Macedonia] | Azotno opterećenje litorala Prespanskog jezera [Bivša Jugoslovenska Republika Makedonija] u toku 2007 godine
2012
Šemo-Zače, M., JNU Hidrobiološki zavod, Ohrid (The Former Yugoslav Republic of Macedonia) | Veljanoska-Sarafiloska, E., JNU Hidrobiološki zavod, Ohrid (The Former Yugoslav Republic of Macedonia) | Jordanoski, M., Veterinaren fakultet, Bitola (The Former Yugoslav Republic of Macedonia)
The aim of this work is to present the water quality of littoral zone of lake Prespa, based on defined physico-chemical parameters (NO3, NO2, NH3, total nitrogen). Samples for analysis were collected with a monthly dynamics during 2007 year (April-December). This period is not chosen by chance, in regard to that the lake basin is constantly under the anthropogenic influence and climate changes that have been registered by this time. According to the obtained results of the performed analyses, basis of the water act of RM and OECD regulation, a categorization of the after was made in the respective measuring points.
Mostrar más [+] Menos [-]Desorption of chosen organochlorine compounds from sediment mediated by XAD-4 resin for assessment of their availability in water-sediment system | Desorpcija odabranih organohlornih jedinjenja sa sedimenta posredstvom XAD-4 smole za procenu njihove dostupnosti u sistemu voda-sediment
2012
Tričković, J., Prirodno–matematički fakultet, Novi Sad (Serbia) | Kragulj, M., Prirodno–matematički fakultet, Novi Sad (Serbia) | Krčmar, D., Prirodno–matematički fakultet, Novi Sad (Serbia) | Leovac, A., Prirodno–matematički fakultet, Novi Sad (Serbia) | Prica, M., Fakultet tehničkih nauka, Novi Sad (Serbia) | Ivančev-Tumbas, I., Prirodno–matematički fakultet, Novi Sad (Serbia) | Dalmacija, B., Prirodno–matematički fakultet, Novi Sad (Serbia)
Desorption kinetics of chosen organochlorine compounds (pentachlorobenzene, lindane and pentachloroaniline) mediated by solid absorbent, XAD-4 macroporous ion-exchange resin, was studied for two different contact times of organic compounds and sediment (15 and 90 days) in order to determine the potentiality of using this sample and fast method for the assessment of (bio)availability of organic pollutants in sediment-water system.
Mostrar más [+] Menos [-]Saprobiologicali analyse [i.e. Saprobiological analysis] of the Peštan River [Serbia] based on aquatic macroinvertebrates | Saprobiološka analiza reke Peštan [Srbija] na osnovu zajednice makrobeskičmenjaka
2012
Kračun, M., Institut za biološka istraživanja Siniša Stanković, Beograd (Serbia) | Marković, V., Institut za biološka istraživanja Siniša Stanković, Beograd (Serbia) | Vasiljević, B., Institut za biološka istraživanja Siniša Stanković, Beograd (Serbia) | Atanacković, A., Institut za biološka istraživanja Siniša Stanković, Beograd (Serbia) | Tomović, J., Institut za biološka istraživanja Siniša Stanković, Beograd (Serbia) | Tubić, B., Institut za biološka istraživanja Siniša Stanković, Beograd (Serbia) | Zorić, K., Institut za biološka istraživanja Siniša Stanković, Beograd (Serbia) | Paunović, M., Institut za biološka istraživanja Siniša Stanković, Beograd (Serbia)
In this paper aquatic macroinvertebrate community of the Peštan River was presented, including the characterisation of the species with regard to saprobic conditions and preference to the mineral substrate type. Sampling was carried out during 2011 at man stream and tributaries. A total of 52 taxa have been identified. According to the ecological classification of the taxa with regard to saprobic conditions for the main stream, the most species belong to the alpha-mesosaprobic group while majority of the species from the tributaries were characterised as beta-mesosaprobic species. The most of registered species preffered substrate type characteristic for lowland river. Results of saprobiological analysis indicate poorer status of the main stream in regard to tributaries.
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