February 28, 2007
GCRIO Program Overview
Our extensive collection of documents.
Archives of the
Global Climate Change Digest
A Guide to Information on Greenhouse Gases and Ozone Depletion
Published July 1988 through June 1999
FROM VOLUME 9, NUMBER 1, JANUARY 1996
OZONE DEPLETION: UV IMPACTS
"UV-B Increases the Harvest Index of Bean (Phaseolus vulgaris
L.), G. Deckmyn (Lab. Plant Ecol., Univ. Antwerp, Universiteitsplein 1, 2610
Wilrijk, Belg.), I. Impens, Plant, Cell & Environ., 18(12),
1426-1433, Dec. 1995.
Studied the effects of small changes in natural UV-B on the photosynthesis,
pigmentation, flowering and yield of bean plants grown in small, half-open
greenhouses of UV-transmitting Plexiglass of different thicknesses. Reduction in
leaf area during the period of vegetative growth resulted in decreased dry
weight after 57 days, but during the subsequent flowering and pod-filling
stages, plants at high UV-B retained their photosynthetic capacity longer.
Combined with other changes, plants under increased UV-B ended up with a small
increase in yield and an important increase in harvest index.
"What Role Does UV-B Radiation Play in Freshwater Ecosystems?"
C.E. Williamson (Dept. Earth & Environ. Sci., Lehigh Univ., 31 Williams Dr.,
Bethlehem PA 18015), Limnol. & Oceanog., 40(2), 386-392,
Increases in incident UV-B radiation is potentially important in aquatic
ecosystems because of the high sensitivity of living organisms, but research to
date has focused largely on marine ecosystems in Antarctica. This review
addresses the potential role of UV-B radiation in fresh waters by taking into
account some of the information available in marine systems and applying recent
advances in our understanding of the ecology of fresh waters. The overriding
conclusion is the potential for complex rather than simple responses in
freshwater ecosystems. Responses are also likely to be related to other
important environmental changes. These factors make the ecology of UV-B
radiation in fresh waters a fertile area for research regardless of future
changes in UV-B radiation.
"A Survey of Ultraviolet-B Radiation in Forests," M.J. Brown,
G.G. Parker (Smithsonian Environ. Res. Ctr., POB 28, Edgewater MD 21037), N.E.
Posner, J. Ecol., 82(4), 843-854, Dec. 1994.
Examines how forest canopies transmit UV-B through different levels, at
different times of day and in different seasons, using primarily measurements
made in a Maryland forest. Combines this information with an existing model of
atmospheric transmission of UV-B to estimate present and future exposures
assuming a decline in stratospheric ozone. The greatest increases in exposure
should appear in the upper canopy in summer, and in the lower canopy in spring.
Discusses how increased UV-B could lead to a shift in the relative abundance of
particular hardwood and softwood species in the southeastern U.S. Whether or not
increased UV-B leads to environmental catastrophe, it seems quite possible that
it could change entire communities.
Guide to Publishers
Index of Abbreviations