Primary production of benthic microalgae in two shallow coastal lagoons of different trophic status in the southern Baltic Sea

Abstract

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 178:179-191 (1999) - doi:10.3354/meps178179 Primary production of benthic microalgae in two shallow coastal lagoons of different trophic status in the southern Baltic Sea Jürgen Meyercordt*, Lutz-Arend Meyer-Reil Institut für Ñkologie, Ernst-Moritz-Arndt-Universität Greifswald, D-18565 Kloster/Hiddensee, Germany *E-mail: meyercor@rz.uni-greifswald.de ABSTRACT: Primary production of undisturbed sediments, taken from 2 shallow coastal lagoons in the southern Baltic Sea, was measured in situ and in the laboratory. In the highly eutrophicated and turbid water (mean attenuation coefficient = 2.97 m-1) of Kirr-Bucht (Darss-Zingster Bodden), chlorophyll a concentrations were about 8 times higher than at moderately eutrophicated (mean attenuation coefficient = 0.66 m-1) Rassower Strom (Nordrügensche Bodden). The difference between the 2 areas in terms of chlorophyll a concentrations of the sediment was smaller (only about 2.5 times higher at Kirr-Bucht). Sediment oxygen consumption rates were similar at both sampling stations, showing a marked seasonal trend. Hourly rates of gross production, measured by in situ incubations, revealed maximal values of 30.0 and 17.6 mg C m-2 h-1 for sediments of Kirr-Bucht and Rassower Strom, respectively. Agreement between production rates measured in situ and in laboratory incubations was acceptable (R2 = 0.833). Irradiance dependency of gross production could be well described by 2 parameters, α (slope of light-saturation curve at low irradiance) and Pm (photosynthetic capacity), of a photosynthesis model. Calculated annual rates for Kirr-Bucht (0.6 m water depth) were 60 g C m-2 yr-1 for gross production and 5 g C m-2 yr-1 for net production. For Rassower Strom (3.4 m water depth), 23 g C m-2 yr-1 for gross production and -31 g C m-2 yr-1 for net production were calculated. If production rates were extrapolated to irradiance conditions at comparable water depths at both sampling locations (e.g. 1 m), the detrimental effect of the eutrophicated water column of Kirr-Bucht on benthic primary production became evident in the gross production rates (Kirr-Bucht: 25 g C m-2 yr-1, Rassower Strom: 51 g C m-2 yr-1) and was even more significant for the net production rates (Kirr-Bucht: -30 g C m-2 yr-1, Rassower Strom: -3 g C m-2 yr-1). At a depth of 1 m, a much higher deficit in the carbon balance for the benthic system of Kirr-Bucht was calculated than for Rassower Strom. Therefore, benthic community respiration at the highly eutrophicated location could not by a large margin be balanced by authochthonous benthic primary production, whereas, at the moderately eutrophicated location, benthic respiration and production were nearly balanced. KEY WORDS: Primary production · Microphytobenthos · Irradiance · Eutrophication · Estuary · Baltic Sea Full text in pdf format PreviousNextExport citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 178. Publication date: March 17, 1999 Print ISSN:0171-8630; Online ISSN:1616-1599 Copyright © 1999 Inter-Research.