Evaluation of Phosphate and Nitrate Removal Capacity of Anodonta cygnea (Unionidae) in Open and Closed Systems

Document Type : Research Paper


1 Associate Prof. of Oceanography, Department of Natural Resources, University of Tehran

2 M.Sc. in Environmental Sciences, Department of Environmental & Energy, Tehran Research & Science Branch, Islamic Azad University


Discharge of agricultural and industrial effluents into surface water resources cause water quality degradation. The swan mussel (Anodonta cygnea) is one of the most important fresh water suspension feeders that can be used for the purpose of pollutant reduction. In order to evaluate the capability of A. cygnea in the reduction of nitrates and phosphates in municipal wastewater, several breeds & Rhyter culture medium were investigated. The results obtained from the open system showed that the growing fresh algae were capable of removing a considerable portion of the dissolved materials. The combined system of mussels and algae had an average nitrate removal efficiency of 76.3% and a phosphate removal efficiency of 75.3%. Based on our results, this breed of mussels may be recommended as a crucial organism in biological wastewater treatment.


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