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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.
Phosphine by bio-corrosion of phosphide-rich iron Полный текст
1998
Glindemann, Dietmar | Eismann, Frank | Bergmann, Armin | Kuschk, Peter | Stottmeister, Ulrich
Phosphine is a toxic agent and part of the phosphorus cycle. A hitherto unknown formation mechanism for phosphine in the environment was investigated. When iron samples containing iron phosphide were incubated in corrosive aquatic media affected by microbial metabolites, phosphine was liberated and measured by gas chromatography. Iron liberates phosphine especially in anoxic aquatic media under the influence of sulfide and an acidic pH. A phosphine-forming mechanism is suggested: Phosphate, an impurity of iron containing minerals, is reduced abioticly to iron phosphide. When iron is exposed to the environment (e.g. as outdoor equipment, scrap, contamination in iron milled food or as iron meteorites) and corrodes, the iron phosphide present in the iron is suspended in the medium and can hydrolyze to phosphine. Phosphine can accumulate to measurable quantities in anoxic microbial media, accelerating corrosion and preserving the phosphine formed from oxidation.
Показать больше [+] Меньше [-]Antiestrogenic activity of anthropogenic and natural chemicals Полный текст
1998
Navas, José María | Segner, H. (Helmut)
A number of natural and man-made chemicals possess antiestrogenic activity, i.e. they antagonize a broad spectrum of estrogen-induced responses in vertebrates. Examples of antiestrogens include dioxin, furan and PCB congeners, certain PAHs, pesticides and indol-3-carbinol derivatives. Major mechanisms of antiestrogenicity are antagonistic action of chemicals at the estrogen receptor, or binding of chemicals to the arylhydrocarbon (Ah) receptor and subsequent interaction with estrogen-responsive genes. Toxicological consequences resulting from antiestrogenic activity have not been conclusively demonstrated to date, although antiestrogenic compounds could critically affect sensitive reproductive and developmental processes.
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 [-]Research Articles Metabolism of phenanthrene in cell suspension cultures of wheat and soybean as well as in intact plants of the water mossFontinalis antipyretica : A comparative study Полный текст
1998
Schrenk, Christiane | Steinberg, Christian E. W.
The metabolism of phenanthrene was studied both in cell suspension cultures of wheat (Triticum aestivum) and soybean (Glycine max), and in intact plants of the water mossFontinalis antipyretica. Metabolism in cell suspension cultures strongly differed between the monocotyle and the dicotyle plant. Only small amounts oftrans-phenanthrene-9,10-dihydrodiole and phenanthrene-9,10-dione were detectable in the wheat culture. Soybean cultures, in contrast demonstrated a strong turnover resulting in a 75% reduction of the initial phenanthrene concentration. Metabolites were phenanthrene-9,10-dione, not further characterized polar metabolites and bound residues. Intact plants ofFontinalis antipyretica metabolized only small amounts of phenanthrene. Data obtained from cell cultures did not provide information for the metabolic potential in intact plants. Therefore standardized tests with model systems like suspension cultures lead to inadequate assessment of the ecological risk of certain xenobiotics.
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