خيارات البحث
النتائج 291 - 300 من 347
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.
Nitrification and denitrification estimates in a Louisiana swamp forest soil as assessed BY N-15 isotope dilution and direct gaseous measurements
1998
Delaune, R.D. (Louisiana State Univ., Baton Rouge, LA (USA). Wetland Biogeochemistry Inst.) | Lindau, C.W. | Sulaeman, E. | Jugsujinda, A.
Risk assessment of conventional crop plants in analogy to transgenic plants النص الكامل
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.
اظهر المزيد [+] اقل [-]Organochlorine contamination in selected estuarine and coastal marine finfish and shellfish of New Jersey
1998
Kennish, M.J. (Rutgers Univ., New Brunswick, NJ (USA). Inst. of Marine and Coastal Sciences) | Ruppel, B.E.
Mercury accumulation in transplanted Hypogymnia physodes lichens downwind of Wisconsin chlor-alkali plant
1998
Bennett, J.P. (Wisconsin Dept. of Natural Resources, Madison, WI (USA). Bureau of Air Monitoring) | Makholm, M.M.
Effects of simulated acid rain on Pinus densiflora: inhibition of net photosynthesis by the pheophytization of chlorophyll
1998
Shan, Y. (Chinese Academy of Sciences, Beijing (China). Research Center for Eco-Environmental Sciences)
Element concentrations in Scots pine needles on radial transects across a subarctic area
1998
Rautio, P. (Oulu Univ. (Finland). Dept. of Biology) | Huttunen, S. | Lamppu, J.
Toxic and sublethal effects of ammonium chloride on a freshwater fish Oreochromis mossambicus
1998
Rani, E.F. (Madras Univ., Madras, Tamil Nadu (India). Dept. of Pharmacology and Environmental Toxicology) | Elumalai, M. | Balasubramanian, M.P.
Determination of acidic pesticides in the drinking water of Greece using capillary gas chromatography mass spectrometry
1998
Tsipi, D. (General Chemical State Lab., Athens (Greece)) | Hiskia, A. | Heberer, T. | Stan, H.J.
Modelling the impact of lowered atmospheric nitrogen deposition on a nitrogen saturated forest ecosystem
1998
Koopmans, C.J. (Amsterdam Univ. (Netherlands). Landscape and Environmental Research Group) | Dam, D. van
