Benthos density and its relationship with sediment condition in the north coast of Gorgan Bay, Golestan Province

The frequency and distribution of benthos species in the north coast of Gorgan Bay (proposed site for cage and pen culture) were studied. Sampling was carried out in three water depths 1, 2 and 3 meters and 10 stations in each depth using Van Veen sampler with 3 replications. Totally, 12 families were identified: Nereidae, Ampharitidae, Spionidae Amphipodae, Osteracodae, Mytilidae, Dreissenidae, Cardidae, Neritidae, Pyrgulidae, .Lithoglyphidae and Planorbidae of which Osteracodae and Ampharitidae with 26% and 1% had maximum and minimum abundance, respectively in all depths. The maximum and minimum abundance of benthos was 6025 per square meter in waters 3 meters deep and 52 per square meter in waters 1 meter deep. In addition, sediment texture and total organic matter (TOM) were analyzed which showed that 2 and 3 meter deep waters had the maximum percent of T.O.M (7.8%) in spring and autumn while the minimum T.O.M (2.5%) in 1 meter deep waters was observed in winter......