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چکیده
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This study aims to assess and monitor physical and chemical parameters of the sea (dissolved oxygen, pH, temperature, salinity, density, pH), nutrients (phosphate, nitrate, nitrite, and silica), phytoplankton, zooplankton and macrobenthic communities in the Noshahr regional water (Chalus: Sardab rud, Nowshahr: Kapoorchal, Anarvr and Sisangan) in four transects perpendicular to the coast in the fall and winter of 1392 (12 stations at depths of 5-10 and 20 m) were sampled. Results explained below. Also the mechanism of sediment transport and shoreline Noshahr Port was examined briefly. Chemical properties examinees using Multi meter (Hach) and Spectrophotometer (specord210): The results indicated range of dissolved oxygen 7.67- 10.65 mg/lit, total alkalinity 3359- 4194 μmol/Kg and pH 8.55- 8/84 respectivly. The concentrations of phosphate (fewer than 5 μg/lit), nitrite (non detection), nitrate (maximium 35.88 μg/lit in autumn) and silica ( maximium 469.27 μg/lit in winter) were very same to last data. Also, there was significant differences in nitrate and silica concentration among stations (P<0.05). Variations of the seawater properties (e.g. temperature, salinity and density) based on the field measurement over the continental shelf of the southern Caspian Sea were investigated. A portable CTD probe was applied for profiling from sea surface to bottom at 12 fixed stations in October 2013 and March 2014. Maximum depth of the profiling stations was more than 40 m in the study area. Vertical structure of temperature in the southern Caspian Sea waters is characterized by a seasonal shallow thermocline through the subsurface layer. Average values of temperature, salinity and density in the first step of field observations were around 27.27oC, 12.29 psu and 1006.61 kg/m3, respectively. While, mean values of mentioned characteristic in the second measurement were around 11.44 oC, 12.19 psu and 1008.17 kg/m3, respectively. According to the vertical structure of sea water pr
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