عنوان مقاله [English]
This study done in the Spring, Summer, Autumn and Winter, at 40 study sites from 8 transect between Astara to border of Hasangholipour. Transect are in Astara, Bandar Anzali, Sefidrood, Tonekabon, Noshahr, Babolsar, Amirabad, Bandar Turkman and the SouthCoast of the Caspian Sea. In each transect, 5 stations at depths of 5 m, 10 m, 20 m, 50 m and 100 m were determined to sample a chapter of depth zero (level) and 10 m, 20 m, 50 m and 100 m by Rutner was performed. A total of 24 species were identified from the phylum Dinoflagella. The maximum density Dinoflagella (28.17 ± 27.14 per cubic meter × 106) and maximum biomass 349 ± 336 mg per cubic meter, respectively. Most species diversity Dinoflagella phylum in winter (17 species) has been that species Exuviaella cordata، Goniaulax polyedra، Peridinium achromaticum، Peridinium latum، Prorocentrum praximum و Prorocentrum scutllum were observed in all seasons. Phylum Dinoflagella with an average density of 28/17 ± 27/14 (the number of cubic meters × 106) and the average biomass annually 349 ± 336 (milligrams per cubic meter) of approximately 9% density and 4% biomass phytoplankton of area in the country.The diversity, the density and biomass Dinoflagella have been significant changes (p<0.05).Ongoing changes in microscopic plants including Dinoflagella can effect on fish migration patterns, their growth rate, mortality rate and of course the critical gas concentrations in the atmosphere.