Primary production of microphytobenthos in the Ems-Dollard Estuary

Abstract

From 1976 through 1978 primary production of microphytobenthos was measured at 6 stations on intertidal flats in the Ems-Dollard estuary using the 14C method. The purpose of the measurements was to estimate the annual primary production at different sites in the estuary and to investigate the factors that influence the rates of primary production. Therefore benthic chlorophyll a and a set of environmental factors were measured. Only primary production correlated sigruficantly with chlorophyll a concentration in the superficial (0.5 cm) sediment layer; other factors (temperature. in situ irradiance) did not correlate with primary production, primary production rate or assimilation number. Annual primary production ranged from ca. 50 g C m-' to 250 g C m-2 and was closely related to elevation of the tidal flat station. However, highest values were also recorded at the station closest to a waste water discharge point in the inner part of the estuary. Annual primary production can be roughly estimated from the mean annual content of chlorophyll a in the sediment. Use of different calculation methods results in annual primary production values that do not differ greatly from each other. Also productivity rates did not differ much over most of the estuary, except at the innermost station which showed a high production rate in combination with high microalgal biomass; this could not be explained by the high elevation of the station alone. A hypothesis is offered to explain the limited primary production of microphytobenthic vegetations.

Temporal variations in microbenthic metabolism and inorganic nitrogen fluxes in sandy and muddy sediments of a tidally dominated bay in the northern Wadden Sea

“…6) is within the range previously reported from the Wadden Sea (Colijn & van Buurt, 1975;van Es, 1982;Rasmussen et al, 1983;Colijn & de Jonge, 1984). According to these studies, the annual primary production cycle can be explained largely by seasonal changes in temperature and daylength.…”

“…The positive relationship with GPP, though, infers that chlorophyll a concentration in surface sediment at the two subtidal stations (A and M) could be a co-factor for the control of benthic primary production, as also suggested for a variety of sediments in the Dutch Wadden Sea (Colijn & de Jonge, 1984).…”

Microphytobenthic dynamics in a Wadden Sea intertidal flat – Part II: Seasonal and spatial variability of non-diatom community components in relation to abiotic parameters

“…Colijn & Dijkema, 1981;Sundba¨ck, 1984;de Jong & de Jonge, 1995;Hamels et al, 2001) was found in the Soltho¨rn tidal flat. The highest mean value in the present study was 198.9 mg chl a m À2 , which ranks in the middle to upper range for intertidal sediments (Colijn & de Jonge, 1984;MacIntyre et al, 1996). The significant variations of abundance and chl a concentration found in May 2008 and May 2009 are probably related to the difference in sediment surface temperature (difference between the two months: 11 C).…”

Application of cross‐flow ultrafiltration for isolating exopolymeric substances from a marine diatom (Amphora sp.)

“…Amphora is a common benthic microalgae found in coastal benthic and pelagic environments (Welker et al 2002;Kasim and Mukai 2006;Facca and Sfriso 2007). Benthic microalgal communities are important primary producers in a wide variety of shallow coastal areas (Cadee and Hegeman 1974;Colijn and De Jonge 1984;Cahoon and Cooke 1992;Barranguet 1997;Nelson et al 1999). Up to 40% of the photosynthetically fixed carbon is lost by benthic and pelagic diatoms as an extracellular release (Fogg 1983;Smith and Underwood 1998;Taylor and Paterson 1998).…”