You are here: Home :: Area NEM :: Life sciences :: Botany

C. Facca, A. Sfriso, G. Socal

Temporal and Spatial Distribution of Diatoms in the Surface Sediments of the Venice Lagoon

The aim of this paper was to improve the knowledge of the primary producers living in the Venice Lagoon by studying the composition and the distribution of the benthic diatom communities populating subtidal surface sediments. The upper 5mm of sediment from four areas distributed between the Malamocco inlet and the mainland north of Venice were collected and analysed. Sampling was carried out monthly for one year (1998–99). Species composition, cell abundance and carbon content were determined by light microscopy after separation of cells from the sediment particles using hydrogen peroxide. A total of 147 taxa were identified, mostly pennate diatoms (Bacillariales) belonging to the genera Amphora, Cocconeis, Navicula, Nitzschia and Pleurosigma. Cell abundance ranged from 0.7 x 10⁶ cells cm^?3, near the Malamocco inlet (Station A), to 10.46 10⁶ cells cm^?3 near the mainland (Station C). Diatom carbon content was between 28 and 380 ?g cm^?3. Seasonal trends were slight, except at Stations D and C where the lowest abundance was found in October–November and the highest one in summer. Significant relationships between benthic diatoms and macrophyte biomass, sediment grain size, underwater light transmission, sediment fluxes and the salinity gradient were found.

Botanica Marina, Walter de Gruyter

Print ISSN: 0006-8055
Volume: 45, 04/2002
Pages: 170 - 183

Show full article (external site)

Show all available items of this journal

 

Area NEM