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Nitrogen and phosphorus leaching from fertilizer applied on golf course: lysimeter study
1998
Wong, J.W.C. (Hong Kong Baptist Univ., Kowloon (Hong Kong). Dept. of Biology) | Chan, C.W.Y. | Cheung, K.C.
Evaluation of tobacco cultivars as bioindicators and biomonitors of ozone phytotoxical levels in Catalonia
1998
Ribas, A. (Barcelona Autonoma Univ., Bellaterra, Barcelona (Spain). Centre de Recerca Ecologica i Aplicacions Forestals) | Filella, I. | Gimeno, B.S. | Penuelas, J.
Effect of soil oxidants KNO(3), MnO(2), and air on methane production in flooded rice soil suspension
1998
Jugsujinda, A. (Louisiana State Univ., Baton Rouge, LA (USA). Wetland Biogeochemistry Inst. and Nuclear Science Center) | Lindau, C.W. | Delaune, R.D. | Patrick, W.H.
Crown condition and nutrient status of red spruce (Picea rubens Sarg.) in West Virginia
1998
Audley, D.E. (Pennsylvania State Univ., University Park, PA (USA). Dept. of Plant Pathology) | Skelly, J.M. | McCormick, L.H. | Jackson, W.A.
Risk assessment of conventional crop plants in analogy to transgenic plants
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.
Mostrar más [+] Menos [-]The bait-lamina test : General aspects, applications and perspectives
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.
Mostrar más [+] Menos [-]Antiestrogenic activity of anthropogenic and natural chemicals
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.
Mostrar más [+] Menos [-]Phosphine by bio-corrosion of phosphide-rich iron
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.
Mostrar más [+] Menos [-]Determination of chemical warfare agents : Gas chromatographic analysis of ethylarsine dichloride by derivatization with dithiols (3rd Communication)
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.
Mostrar más [+] Menos [-]Investigations on interception and translocation of airborne (85)Sr, (131)I, (137)Cs in beans, spinach and radish plants
1998
Singhal, R.K. (Bhabha Atomic Research Center, Bombay (India). Health Physics Div.) | Narayanan, U. | Bhat, I.S.