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Report. IMO/FAO/UNESCO/WMO/WHO/IAEA/UN/UNEP Joint Group of Experts on the Scientific Aspects of Marine Environmental Protection. Sess. 25
1995
Growth responses and foliar sensitivities of native herbaceous species to ozone exposures Полный текст
1995
Bergmann, Elke | Bender, Jürgen | Weigel, Hans-Joachim
For the assessment of the phytotoxic effects of current ozone (O3) in the lower troposphere, sensitive biological indicators are required, which allow an early indication of the impact of this gas. There is very little information concerning the usefulness of non-crop species for this purpose. This paper reports on open-top chamber studies investigating the effects of different O3 exposures on native herbaceous plant species. Plants were grown up from seeds, potted into natural soils and exposed to near-ambient O3 levels during one growing season. A wide range of visible symptoms was apparent during the exposures. Species such as Rumex obtusifolius, Senecio vulgaris or Sonchus asper showed leaf colorations (e. g. red-dish pigmentation) that probably indicate a non-specific stress response. In other species especially of the genera Malva and Cirsium the symptoms produced by O3 appeared to be similar to those characteristic for O3-specific foliar injury (stippling, flecking). In almost all species tested, O3 caused premature leaf senescence, which was sometimes associated with premature leaf abscission. However, earlier senescence did not necessarily result in changes in plant growth. Of all species tested, Malva sylvestris was found to be the most sensitive in terms of growth reduction and lower seed production.
Показать больше [+] Меньше [-]Basin sub-basin inventory of water pollution Godavari Basin
1995
Basin sub-basin inventory of water pollution Cauvery Basin | Cauvery Basin
1995
Wisconsin's forestry best management practices for water quality | Best management practices for water quality | Field manual for loggers, landowners and land managers
1995
Holaday, Steve
Statewide screening of groundwater nitrate pollution potential from agricultural lands in Pennsylvania
1995
Hamlett, James M.
The bioeconomics of regulating nitrates in groundwater from agricultural production through taxes, quantity restrictions, and pollution permits
1995
Thomas, Arthur C. | Boisvert, Richard N.
