خيارات البحث
النتائج 1 - 10 من 79
Reponses des vegetaux d' une region aride a une pollution atmospherique double: (SO2 + composes fluores).
1994
Ferjani B.A. | Belgacem H. | Makki B.
Long-term effects of pollutants on forest vegetation in Central Spis region
2002
Mankovska, B. (Forest Research Institute, Zvolen (Slovak Republic))
Pollution problems in forest ecosystems resulting from 100 year long operation of three smelter complexes in Central Spis are reviewed. Original data are presented with respect to temporal and spatial trends of nitrogen, sulphur and heavy metal pollution, and elemental composition of individual aerosols on leaf surface. Spruce stands in Central Spis are loaded by pollutants 1.7 times more than are critical values and the highest concentrations of As, Fe, Hg, and N were found in this region. Low Tatra National Park was the cleanest region where no element maxima were found
اظهر المزيد [+] اقل [-]Discussion of the effects of N with and without acidified S on a sitka spruce ecosystem after 5 years treatment
2002
Sheppard, L.J. | (CEH Edinburgh Bush Estate, Edinburgh (United Kingdom)) | Crossley, A. | Ingleby, K. | Carfrae, J. | Harvey, F. | Kennedy, V.
Significant differences in the effects of N alone compared with NS Acid have been found with respect to eutrophication and acidification. N alone had no effect on the pleurocarpous mosses, whereas NS Acid caused their death within 2 years. Both treatments enhanced stem area increment and N alone also doubled fine root growth. By contrast NS Acid treatments increased litterfall in a a dose response fashion
اظهر المزيد [+] اقل [-]Long-term effects of air pollution on spruce forests in the Tatra Mts. - ozone and vegetation studies
2002
Godzik, B. (Polish Academy of Sciences, Krakow (Poland). Institute of Botany) | Fleischer, P. | Grodzinska, K.
Wet-deposited - sulphur and nitrogen pollutants and ambient ozone are important anthropogenic factors affecting forest health. Regular assessment of chemistry of throughfall and precipitation water based on two-week sampling started in 1997. Passive samplers for detection of ozone concentration have been exposed on a network of monitoring stations during vegetation periods since 1998. In addition, in selected locations, UV absorption monitors for continuous O3 measurements were installed in 1999
اظهر المزيد [+] اقل [-]The spatial distribution of different elements in and on the foliage of Norway spruce growing in Switzerland
1989
Landolt, W. | Guecheva, M. | Bucher, J.B. (Swiss Federal Institute of Forestry Research, 8903 Birmensdorf (Switzerland))
Effects of air pollutants on vegetation in the region of Sfax (Tunisia) [cultivated and wild plants]
1990
Ben Abdallah, F. (Faculte des Sciences de Sfax (Tunisia)) | Boukhris, M.
Throughfall deposition of nitrogen and sulfur in a Jeffrey pine forest in the San Gabriel Mountains, southern California
1999
Fenn, M.E. | Kiefer, J.W. (US Department of Agriculture, Forest Service, Pacific Southwest Research Station, Forest Fire Laboratory, 4955 Canyon Crest Drive, Riverside, CA 92507 (USA))
Longitudinal patterns of stream chemistry in a catchment with forest dieback, Czech Republic
1999
Havel, M. | Peters, N.E. | Cerny, J. (Czech Geological Survey, Klarov 3/131, Praha 1 (Czech Republic))
EMEP eulerian model for atmospheric transport and deposition of nitrogen species over Europe
1998
Jonson, J.E. | Bartnicki, J. | Olendrzynski, K. | Jakobsen, H.A. | Berge, E. (Meteorological Synthesizing Centre - West of EMEP, The Norwegian Meteorological Institute, P.O. Box 43, Blindern N-0313 Oslo (Norway))
Response of a grassland ecosystem to air pollutants. VI. The chemical climate: concentrations and potential flux densities of relevant criteria pollutants
1998
Grunhage, L. | Dammgen, U. | Haenel, H.D. | Jager, H.J. (Institute for Plant Ecology, University of Giessen, Heinrich-Buff-Ring 38, D-35392 Giessen, Germany)
