Seasonal variability of planktonic copepods in Tunis North Lagoon (Tunisia, North Africa)

Abstract

This paper describes temporal and seasonal variations in the composition and abundance of the planktonic cope- pod community in the North lagoon of Tunis and the influence of selected environmental factors (temperature, salinity, sus- pended particulate matter and chlorophyll a concentrations) on this community. Samples were collected weekly from March 2001 to September 2002. Total planktonic copepod abundance showed low densities and high variability, lacking any clear seasonal pattern. In total, 24 species were identified. According to their occurrence and numerical abundance during the study period, Oithona nana, Acartia clausi and Euterpina acutifrons constituted the dominated species of the planktonic copepod community in the lagoon. There was a significant correlation between the abundance of copepods and environmental factors in the case of Acartia latisetosa, Oithona plumifera, Labidocera brunescens, Euterpina acutifrons, Clausocalanus arcuicornis and Corycaeus speciosus.