Is UV-B radiation affecting charophycean algae in shallow freshwater systems?de Bakker, NVJ., van Bodegom, PM., van de Poll, WH., Boelen, P., Nat, E., Rozema, J. & Aerts, R., Jun-2005, In : New Phytologist. 166, 3, p. 957-966 10 p.
Research output: Contribution to journal › Article › Academic › peer-review
The objective of this study was to determine the effects of UV-B radiation on charophycean algae under natural conditions, since charophytes enhance water transparency in freshwater systems and levels of UV-B radiation have increased by ozone depletion.
Potential and actual UV-B effects were studied by combining a glasshouse experiment in which plants were exposed to various levels of UV-B radiation and field measurements in two freshwater systems dominated by charophytes in the Netherlands.
The glasshouse experiment showed that charophytes were sensitive to UV-B radiation. UV-B radiation negatively affected growth, while it increased levels of DNA damage in Chara aspera. Moreover, the charophytes did not seem to develop UV-B screens to protect against UV-B radiation since no increase in UV-B absorbing compounds was found.
At field conditions, both spectroradiometrical measurements and DNA dosimeters showed that UV-B radiation was attenuated quickly in both freshwater systems, indicating that UV-B does not reach the submerged charophyte vegetation. However, specific conditions, like fluctuating water tables, may result in UV-B exposure to charophytes for certain periods annually.
|Number of pages||10|
|Publication status||Published - Jun-2005|
- attenuation coefficients, charophycean algae, DNA damage, DNA dosimeters, freshwater ecosystems, growth, UV-B absorbing compounds, UV-B radiation, SOLAR ULTRAVIOLET-RADIATION, INDUCED DNA-DAMAGE, DISSOLVED ORGANIC-CARBON, TERRESTRIAL ECOSYSTEMS, OZONE DEPLETION, REPAIR, LAKES, PHOTOREACTIVATION, ATTENUATION, MACROPHYTES