Phytoplankton and Nutrient Variations in the Iranian Waters of the Caspian Sea (Guilan region) during 2003-2004

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BAGHERI S., TÜRKOĞLU M., ABEDINI A.

TURKISH JOURNAL OF FISHERIES AND AQUATIC SCIENCES, vol.14, no.1, pp.231-245, 2014 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 14 Issue: 1
  • Publication Date: 2014
  • Doi Number: 10.4194/1303-2712-v14_1_25
  • Journal Name: TURKISH JOURNAL OF FISHERIES AND AQUATIC SCIENCES
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, TR DİZİN (ULAKBİM)
  • Page Numbers: pp.231-245
  • Keywords: Phytoplankton, checklist, cell density, nutrient, Caspian Sea, MNEMIOPSIS-LEIDYI, BLACK-SEA, TEMPORAL DISTRIBUTION, EMILIANIA-HUXLEYI, MARINE DIATOMS, CHLOROPHYLL-A, DARDANELLES, ZOOPLANKTON, CTENOPHORE, SYSTEM
  • Çanakkale Onsekiz Mart University Affiliated: Yes

Abstract

This study concentrated on temporal distribution and species composition of phytoplankton connected with physicochemical variations between January 2003 and November 2004 in the South Western Caspian Sea. During the study, 75 phytoplankton were distinguished in total and average phytoplankton densities in 2003 and 2004 were 1.47×105 ±6.05×104 and 1.97×105 ±7.18×104 cells L-1, respectively. Contributions of diatoms (66.0% in 2003; 57.0% in 2004) and cyanophytes to total phytoplankton (17.0 in 2003; 36.0% in 2004) were higher than any other group. Diatoms Dactyliosolen fragilissimus and Thalassionema nitzschioides, and cyanophytes Oscillatoria sp. and Anabeanopsis raciborskii provided the biggest contributions to the total phytoplankton. Average DIN concentration in 2003 was higher (3.86±1.65 µM) than the average in 2004 (3.37±1.13 µM). However, average DIP concentration in 2003 was lower (1.45±1.37 µM) than the average in 2004 (1.99±0.67 µM). Average DIS concentration was two-fold higher than average DIN concentration. Average DIN:DIP without NH4 (2.66±1.66 in 2003; 1.69 ± 1.17 in 2004) and DIS:DIP ratios (5.61±3.44 in 2003; 3.93±2.49 in 2004) were clearly lower than Redfield ratios. Nutrient ratios and phytoplankton densities revealed that system was eutrophic.

Keywords: Phytoplankton, checklist, cell density, nutrient, Caspian Sea

This study concentrated on temporal distribution and species composition of phytoplankton connected with physicochemical variations between January 2003 and November 2004 in the South Western Caspian Sea. During the study, 75 phytoplankton were distinguished in total and average phytoplankton densities in 2003 and 2004 were 1.47x10(5)+/- 6.05x 10(4)and 1.97x10(5)+/- 7.18x10(4) cells L-1, respectively. Contributions of diatoms (66.0% in 2003; 57.0% in 2004) and cyanophytes to total phytoplankton (17.0 in 2003; 36.0% in 2004) were higher than any other group. Diatoms Dactyliosolen fragilissimus and Thalassionema nitzschioides, and cyanophytes Oscillatoria sp. and Anabeanopsis raciborskii provided the biggest contributions to the total phytoplankton. Average DIN concentration in 2003 was higher (3.86 +/- 1.65 mu M) than the average in 2004 (3.37 +/- 1.13 mu M). However, average DIP concentration in 2003 was lower (1.45 +/- 1.37 mu M) than the average in 2004 (1.99 +/- 0.67 mu M). Average DIS concentration was two-fold higher than average DIN concentration. Average DIN: DIP without NH4 (2.66 +/- 1.66 in 2003; 1.69 +/- 1.17 in 2004) and DIS: DIP ratios (5.61 +/- 3.44 in 2003; 3.93 +/- 2.49 in 2004) were clearly lower than Redfield ratios. Nutrient ratios and phytoplankton densities revealed that system was eutrophic