Effects of environmental variables on Oligochaeta (Annelida) assemblages in Çardak Lagoon (Turkish Straits System)

This study aimed to investigate the relationships between the abundance of the Oligochaeta assemblages in Çardak Lagoon, an area impacted by domestic pollutants. A total of 3 oligochaeta species [(Thalassodrilides gurwitschi (Hrabĕ, 1971), Thalassodrilides sp., and Oligochaeta sp.] were recorded. The peak abundance periods for these communities were determined to be spring and summer. Analysis of the environmental variables across the sampling seasons revealed that the anionic detergent level in the water and the percentage of gravel in the sediment exhibited the highest correlation with overall oligochaete abundance. At the sampling points, the maximum correlation value was recorded specifically between the percentage of organic matter (OM%) in the sediment and the abundance of Thalassodrilides gurwitschi.