Determination of sediment grading, Total Organic Matter and facultative anaerobic bacteria affected by rainbow trout culture in floating cage in the Abbas Abad area, southern basin of the Caspian Sea

Document Type : Research Paper

Authors

1 Department of Fisheries, Faculty of Marine Natural Resources, Khorramshahr University of marine science and Technology, Khorramshahr, Iran

2 Head of Aquaculture Department Caspian Sea Ecology Research Institute

3 null

Abstract

This study was designed to determine the sediment structure, Total Organic Matter (TOM) and facultative anaerobic bacteria communities of sediment affected by cage culture of rainbow trout in the coastal waters of Abbas Abad area (southern basin of the Caspian Sea). For this purpose, sediment samples were collected at distance of 5, 50, 100 and 1000 m from the cages in December 2014 (before the culture period), March and April (production period) and August 2015 (after the culture period). Determination of sediment grading showed that its structure was composed of silt-clay (91.7%) and very fine sand (6.44%) and the sediment structure was not affected by the cage culture. The Total Organic Matter was significantly different only between the sampling periods (P<0.05) so that the highest amount of Total Organic Matter (TOM) was observed during the production period whereas, it was not affected by the distance from the cages (P<0.05). It seems that the rainbow trout cage culture in the Abbas Abad region no remarkable effect on the factors studied in the vicinity of small scale fish cages due to the short duration of cage culture and strong water currents, so that observed changes were more associated with seasonal fluctuant.

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