Modern Benthic Diatom Distribution in a Hypersaline Coastal Lagoon: the Lagoa de Araruama (R.J.), Brazil

Diatom assemblages from 75 surface sediment samples in a hypersaline, coastal lagoon in Brazil near Rio de Janeiro were characterized to determine whether correlations existed with human activities. Specific assemblages were identified in different parts of the lagoon, and were related to bathymetrical fluctuations influenced by ocean and river inputs, as well as to salinity fluctuations influenced by marine water and precipitation-evaporation rates. Some of the assemblages contain components that indicate human-induced effects (e.g., from sewage and salt extraction). Seasonal variation in tourism and expansion of the tourism industry in the region may further affect diatom assemblages.