| one publication added to basket [6345] | Significance of microphytobenthic primary production in the Bodden (southern Baltic Sea)
Gerbersdorf, S.; Black, H.J.; Meyercordt, J.; Meyer-Reil, L.-A.; Rieling, T.; Stodian, I. (2000). Significance of microphytobenthic primary production in the Bodden (southern Baltic Sea), in: Flemming, B.W. et al. (Ed.) Muddy coast dynamics and resource management. Proceedings in Marine Science, 2: pp. 127-136
In: Flemming, B.W.; Delafontaine, M.T.; Liebezeit, G. (Ed.) (2000). Muddy coast dynamics and resource management. Proceedings in Marine Science, 2. Elsevier: Amsterdam. ISBN 0-444-50464-8. 294 pp., more
In: Proceedings in Marine Science. Elsevier: New York. ISSN 1568-2692; e-ISSN 2352-2860, more
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| Authors | | Top |
- Gerbersdorf, S.
- Black, H.J.
- Meyercordt, J., correspondent
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- Meyer-Reil, L.-A.
- Rieling, T.
- Stodian, I.
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| Abstract |
Investigations of phytoplankton and microphytobenthic primary production were carried out at two estuarine study sites located in the southern Baltic Sea (Germany). Special attention was given to the balance between pelagic and benthic primary production which is widely considered to have become disturbed by eutrophication in the region, as well as to the importance of the flocculent sediment surface layer for primary production. Study site A, the Rassower Strom, is situated in the Nord-Rügensche Boddenkette whereas study site B, the Kirr-Bucht, is located in the central part of the Darß-Zingster-Boddenkette. At both sites, pelagic production dominated total primary production (85%). The microphytobenthos contributed sunstantially to total production, with gross production rates measuring up to 2 mmol C m-² h-¹. Despite site-specific differences in physical conditions, the contribution of benthic primary production to total primary production was comparable at both sampling sites. The combination of water depth (high at study site A, and low at study site B) and light attenuation coefficient (low at study site A, and high at study site B) led to similar light regimes at the sediment surface in both cases. Calculated P-E curves (photosynthesis versus irradiance) based on primary production measurements in the laboratory showed highest P max and Ek values in summer. At all seasons, light saturation of the microphytobenthos occurred at rather low irradiance (about 70 µE m-² s-¹) which might indicate a physiological adaptation of the microalgae to low light conditions. The more eutrophic and the deeper the water, the more irradiance will limit photosynthesis of microphytobenthic organisms.In a flocculent layer consisting of algae and detrital aggregates on top of the sediments, photoautotrophic processes dominated due to low respiration rates. The removal of the surface layer enhanced the primary production of the sediment below, presumably because buried cells became photosynthetically active again. Especially in the rather shallow Bodden where wind-induced currents and waves cause resuspension of bottom sediments, previously buried algae may thus contribute to primary production. |
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