Journal of Marine Biology

This study was conducted to determine phosphorous and nitrogen species at the surface sediment in the Mazandaran Coasts (Kelarabad City). Surface sediments samples were collected at three stations during autumn 2011 to winter 2012. All samples were prepared by digesting and extracting processes and then determined using spectroscopy instrument. Result showed that inorganic phosphorous was less than organic phosphorous, however, percent mean of residue-P which contain organic compounds and non-degradable compounds, was more than 50 percent. Percent of Ca-P was higher than 60, whereas Available-P was less than 40 percent. In addition, Fe-P and Adsorbed -P were registered maximum and minimum values among the bioavailable phosphorous, respectively. The order of different forms of phosphorous were registered Res.-P>Ca-P>Fe-P>Al-P>Adsorbed-P. Annual percent of TIN was two folds than TON and concentration of NH4/N was also four times than NO3/N. As a conclusion, the results revealed that main role of available-P adsorbed and desorbed were temperature, Eh and pH. Also, the form of NH4⁺/N was high percentage because of anaerobic condition of the sediment. According to high ratios of nitrogen and phosphorous of sediment to nitrogen and phosphorous of bottom water, it finds that released of those from sediment to water will be happened with high rate. Therefore, it is expected that the establishment of fish farming cages carried out more precautionary approach which not leads to increased algae bloom. It is appropriate that the establishment of fish farming cages carried out as a pilot to more precautionary approach which not lead to environmental disaster.