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Результаты 261-270 из 347
Invertebrates in woodlands polluted by heavy metals: an evaluation using canonical correspondence analysis
1998
Read, H.J. (Bristol Univ. (United Kingdom). Dept. of Botany) | Martin, M.H. | Rayner, J.M.V.
Assessment of the exposure and loads of acidifying and eutrophying pollutants and ozone, as well as their, harmful influence on the vitality of the trees and the Speulder forest ecosystem as a whole
1998
Erisman, J.W. (Rijksinstituut voor Volksgezondheid en Milieuhygiene, Bilthoven (Netherlands).) | Draaijers, G.P.J. | Steingrover, E. | Dijk, H. van | Boxman, A. | Vries, W. de
Levels of lead and other metals in citrus alongside a motor road
1998
Caselles, J. (Ciudad Universitaria, Madrid (Spain). Escuela Tecnica Superior de Ingenieros Industriales, Dept. de Quimica Aplicada a la Ingenieria)
Sulfate adsorption-desorption in a Swedish forest soil
1998
Gobran, G.R. (Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Ecology and Environmental Research) | Selim, H.M. | Hultberg, H. | Andersson, I.
Three species of genus Pinus suitable as bioindicators of polluted environment
1998
Micieta, K. (Comenius Univ., Bratuslava (Slovak Republic). Inst. of Cell Biology) | Murin, G.
Base cation supply in spruce and beech ecosystems of the Strengbach catchment (Vosges mountains, N-E France)
1998
Fichter, J. (Equipe Cycles Biogeochimiques de l'Unite Ecosystemes Forestiers INRA, Champenoux (France).) | Dambrine, E. | Turpault, M.P. | Ranger, J.
Risk assessment of conventional crop plants in analogy to transgenic plants Полный текст
1998
Torgersen, Helge | Soja, Gerhard | Janssen, Ines | Gaugitsch, Helmut
The risk assessment of genetically-modified plants pursuant to Annex II B of EU Directive 94/15/EC assumes that it is possible to infer the environmental impacts of a crop plant from its characteristics, so most of Annex II should also be applicable to conventional plants. To test this, we surveyed reports on the ecological impacts of the cultivation of non-transgenic crop plants with novel or improved traits and, in three cases, investigated whether Annex II B would have been adequate to indicate the effects. Such an assessment appears to be feasible only if the time frame on which it is based is short, so that long-term effects cannot be assessed. Secondly, the plant must be genetically homogenous which is not always granted, e.g. with forest-trees. Thirdly, the cultivation area must be defined. Differences in the behaviour of foreign plants between their original and cultivation habitats may be ecologically relevant and should be assessed. In the (few) cases where direct inference of the observed effects was possible from inherent traits, these effects often correlated with poor adaptation to local environmental conditions. The ecological impacts of traits that had been introduced in order to overcome poor adaptation may differ widely according to the way in which the traits are exploited. In practice, the effects of agricultural measures are more important than the effects of gene transfer and invasiveness, although the latter currently play a major role in risk assessment. In the light of these deliberations, a modification of Annex II B of EU Directive 94/15/EC is suggested.
Показать больше [+] Меньше [-]The bait-lamina test : General aspects, applications and perspectives Полный текст
1998
Kratz, Werner
A general introduction of the bait-lamina test has been made in this article. This article has an introductional character for other articles dealing with the bait-lamina test method and gives the experimental data.The test was first introduced by Törne in 1990 to measure the biological activity of soil. It enables the monitoring of biotic (microbial and zootic) processes in the soil within a short period of time, and detailed investigations. The test system is based on visual assessment of feeding on small portions of thin laminated bait substrate exposed to edaphic processes. The test system has found its application mainly in Germany but in the meanwhile also in Portugal, Switzerland and in the Netherlands in laboratories of soil ecology and soil ecotoxicology. At present there are only few publications in the international literature, but the interest in this method is growing. During the past years two workshops on the subject have been organized in Germany to summarize experiences with and to evaluate the test system and optimize the standard procedure.
Показать больше [+] Меньше [-]Determination of chemical warfare agents : Gas chromatographic analysis of ethylarsine dichloride by derivatization with dithiols (3rd Communication) Полный текст
1998
Haas, Rainer
Ethylarsine dichloride was used during WW I as a chemical warfare agent. Residues of this chemical warfare agent and its metabolites are still present today and continue to contaminate soil and water.A gas Chromatographic method for the detection and determination of ethylarsine dichloride is shown. Six dithiols were tested as possible derivatization reagents for ethylarsine dichloride. With selection of the dithiol, matrix interferences can be eliminated because of the different retention times of the derivatives.
Показать больше [+] Меньше [-]Mercury in precipitation and its relation to bioaccumulation in fish: a literature review
1998
Downs, S.G. (Imperial Coll. of Science, Technology and Medicine, London (United Kingdom). Imperial Coll. Centre for Environmental Technology) | Macleod, C.L. | Lester, J.N.