Open Access Journal of Marine Biology and Environmental Sciences Volume 2 Issue 1 ISSN: 2694-5924 Research Article Study on Cyanobacteria Population in Iranian Waters of the Caspian Sea during 2010- 2011 Tahami F* Department of Caspian Sea Ecology Research Center (CSERC), Iranian Fisheries Science Research Institute (IFSRI), Agricultural Research, Iran

Article Info Abstract

Article History: Since awareness of the cyanobacteria population of each ecosystem is important, the aim of this study is Received: 04 May, 2020 Accepted: 12 May, 2020 focuses on cyanobacteria population of Iranian waters of the southern Caspian Basin. The present study Published: 15 May, 2020 was conducted in southern part of Caspian Sea, Iran. All samples were taken during 2010-2011 through

spring, summer, autumn and winter, in 32 stations from 8 transects (Astara, Anzali, Sefidrood, * Corresponding author: Tahami Tonekabon, Noshahr, Babolsar and BandarTurkman). In each transect 5 stations in different depths of 5 FS, Department of Caspian Sea Ecology Research Center (CSERC), m, 10 m, 20 m, 50 m and 100 m were defined that the seasonal sampling were performed from the depth Iranian Fisheries Science Research of zero (surface), 10 m, 20 m, 50 m and 100 m by Ruttner Water Sampler, and then transferred to Institute (IFSRI), Agricultural laboratory of Caspian sea ecological institute. Then the samples transferred to laboratory of Ecological Research, Iran; DOI: Academy, kept in cool and darkness in properly capped glass bottles. The cyanobacteria were analyzed https://doi.org/10.36266/JMBES/108 on a “Nikon” light microscope at ×480 magnification. Algae abundance was determined using the Hydro bios counting chamber and sampled (volume 0.1 ml). The volume of each cell was then calculated by measuring its appropriate morph metric characteristics and geometric. A total of 19 species, that belong to 10 different genera, showed significantly decrease with increasing depth, especially at the depth of less than 20 m (P<0.05). The Cyanobacterial compositions were significantly changed with seasons and depths, and depth and the maximum cell abundance and biomass observed in summer. The Microscopic Cyanobacteria species were identified. (P<0.05) and Shannon index was different for different seasons.

Keywords: Cyanobacteria; Population; Depth; Season; Caspian sea; Iranian waters

Copyright: © 2020 Tahami F. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

especially in warm seasons (Microcystis, Nodularia, and Introduction Anabaena). Even though the Cyanobacteria are classified as Cyanobacteria are blue-green algae that contain prokaryotic cells bacteria (lacking a membrane-bounded nucleus) they are and are able to photosynthesize because of their chlorophyll. photosynthetic and are included among our algal collections [2]. These organisms are a part of the planktonic communities of Early studies by researchers have shown that cyanobacteria aquatic ecosystems [1]. Cyanobacteria can have effect on the generally have beneficial effects on reducing infections and the water quality of different aquatic ecosystems like Caspian Sea [2]. intervention of these microorganisms through physical or The Southern Caspian Sea adjacent to the three provinces of Iran; chemical processes is not very complicated. Given the importance Golestan, Mazandaran, and Gilan, is located in the northern part of cyanobacteria in aquatic ecosystems, the aim of this study was of the Alborz Mountains. The rivers such as Sefidrood, to identify different species of cyanophytes and their density in Gorganrood, Tajan, Haraz, Shirood, Sarabrood, Talar, and the southern Caspian Basin. Babolroodare ended in this sea. Since Cyanobacteria are Material and Methods important in aquatic ecosystems and study on cyanobacteria is necessary, especially the species identification, biomass density, This study was conducted in the southern Caspian Sea basin, regional alternation, and various factors that affect the ecosystem. which where the sampling at different stations and depths were Also Nutrient enrichment may give rise to shifts in Cyanobacteria performed for one year and by the Gilan research vessel and species composition and biomass. Furthermore, an increase in the Rottner sampler (maximum volume of 2 liters) in spring, summer, frequency, magnitude and duration of harmful Cyanobacteria autumn and winter, of 2010. Sampling areas were selected at the blooms may occur. In southern Caspian Sea, the wet and dry 8 transects: Astara, Bandar Anzali, Sefidrood entrance, seasons can change the nutrients and benthic communities. Sea Tonekabon, Noshahr, Babolsar, and Amir Abad port (Figure 1). blooming of some Toxic Cyanobacterias in Southern Caspian Sea In each transect, 5 stations at the depths of 5, 10, 20, 50 and 100 can occur because of the influence of industrial and agricultural m were considered and the sampling was conducted by a Guilan pollutants in those rivers that arrives to the Southern Caspian Sea research ship. Caspian Institute of Ecology Research

Pubtexto Publishers | www.pubtexto.com 1 J Marine Biol Environ Sci Citation: Valentina P, Valerian N, Razvan B (2020). Study on Cyanobacteria Population in Iranian Waters of the Caspian Sea during 2010-2011. J Marine Biol Environ Sci 2(1): 107 DOI: https://doi.org/10.36266/JMBES/108

Planktonology Laboratory analysis was performed according to biomass showed a normal distribution. Comparisons of the mean the APHA (American Public Health Association) [3]. data were performed by multiple analyses of variance (ANOVA) and Duncan test. In variance analysis, the density and biomass of different branches were considered as dependent variables. The species diversity index was calculated according to the Shannon- Weaver formula [5] and by following formula: 1 퐻 = − ∑ 푃푖 ln 푃푢 퐻1 is the Shannon-Weaver index (nits per individual), and is the relative abundance of species. Results In this study 19 species belonging to 10 genera of Cyanophyta were identified. The studies have indicated that Cyanobacteria have an essential role in the primary production in the ecosystem Figure 1: Sampling stations in the southern basin of Caspian Sea, 2010. according to the environmental conditions. The number of Cyanobacteria species observed in different seasons varied and the least species were observed in spring and most species in autumn and winter (Figure 3). In the seasonal study of different branches of Microscopic Algae, the highest density was in the autumn, 285.7 ± 137.1 in (m3) and the maximum biomass was in the summer, 105.81 ± 38 (mg/m3) (Table 1). As shown in Figure 2 the highest Shannon index (H′) was observed in the spring and it gradually decreased during the summer, autumn and winter. The highest Shannon index was in the west area in spring (0.96), and the lowest Shannon index was in the East region in the autumn season (0.47) (Figure 4) [5].

Figure 3: The number of species of cyanobacteria in different seasons.

Figure 2: Genera identified in this study. In this method, for deposition, the specimens were kept in the dark for 10 days. Then it with a special siphon, and the remaining sample centrifuged at a speed of 3,000 rpm for 5 minutes then Discard supernatant to reach a volume of 20-25ml. In the laboratory, the samples were investigated and microscopically counted in two qualitative steps and one quantitative step by the slabs and lamellas of 24×24 mm [4]. Calculations of mean and Figure 4: Shannon index (H) for microscopic algae in different seasons standard deviations and preparation of their figures were in 2010- 2011. performed by Excel 2007 software. Frequency data and the Algae Pubtexto Publishers | www.pubtexto.com 2 J Marine Biol Environ Sci

Citation: Valentina P, Valerian N, Razvan B (2020). Study on Cyanobacteria Population in Iranian Waters of the Caspian Sea during 2010-2011. J Marine Biol Environ Sci 2(1): 107 DOI: https://doi.org/10.36266/JMBES/108

Table 1: Density (number in m3 × 106) and biomass (mg/m3) of Cyanobacteria in different seasons in 2010 - 2011. Spring Summer Autumn Winter

Density Biomass Density Biomass Density Biomass Density Biomass (m3) (mg/m3) (m3) (mg/m3) (m3) (mg/m3) (m3) (mg/m3)

13.6 ± 7.4 7.5 ± 10 158.2 ± 134.4 105.81 ± 38 285.7 ± 137.1 95 ± 54 10.4 ± 2.4 5 ± 2.2

have no pigments. The results of this study showed that the Table 2: Checklist of cyanobacteria species during 2010-2011. dominant specimens of cyanobacteria were genotypes Anabaena, Anabaena bergii Nodullaria spumgina Aphanizominon, Aphanothece, Chroococcus, Lyngbya, Merismopedia, Nodullaria, Oscillatoria, Spirulina and A. aphanizomenides Oscillatoria limosa Gloeacapsa. In the year 1998, the identification of different A. spiroides O. agardhii cyanobacteria species by a cadre in Lake Keban, Turkey found that temperature and increased light were positive factors for A. hisselevii O. sp. species growth, especially cyanobacteria. However, the highest density of cyanobacteria was observed in autumn and then in Aphanizominon flos-aqua O. tennuis summer, which may be due to the growth of large-sized species in Ap. sp. Spirulina laxissma summer [12]. Increased Cyanobacterial population is usually linked to human activities such as agriculture that result in excess Aphanothece sp. S. sp. nutrient inflow into the waters [13,14]. During 2010-2011 the percentage of cell abundance and biomass of Cyanobacteria in Chroococcus sp. Gloeacapsa limnetica different seasons were significant changed (P<0.05) and the Lyngbya limnetica - species of cyanobacteria decreased with decrease temperature in winter [18]. They may proliferate and form blooms under certain L. sp. - conditions, particularly when high levels of nutrients are available. Cyanobacteria are of toxicological interest because Merismopedia minima - several genera of cyanobacteria have the ability to produce toxins, and it is generally more common during warmer weather in Discussion summer, but can occur at any time of the year [17]. On base on this study, one can tell that with increasing temperature in Cyanobacteria exhibit in addition to the adaptability to regulate summer in Caspian Sea, increases its biodiversity. Sze stated in buoyancy, the regulation of pigment pools in response to both his observations that in the warm season (summer), due to rising quantity and quality of light. Hence it could be said the presence ambient temperatures and water, the density of cyanobacteria of higher number of species of the Cyanophyta in the dry and increases, which is consistent with the results of the above study rainy season, respectively is indicative of the water quality in the [15]. That is, with the onset of the warm season of the year, the different seasons. Our study demonstrates that across Southern temperature and biomass of cyanobacteria increase as well. Caspian Sea, varied environmental conditions and morphometry, Cyanobacteria are nitrogen fixers due to their heterocyst nodes, pronounced season and temperature gradients favor the which can be a factor in their growth [16]. Shannon-Weaver distribution of bulk Cyanobacteria into more defined layers and index shows three water quality classes. Figure 4 has shown seasons, while the depth of the peak and the heterogeneity of Shannon-Weaver index diversity index, which implies that the individual Cyanobacteria were differentially affected by habitat high value suggests healthier ecosystem and the low value structure [8,9]. Cyanobacteria habitat structure was relatively suggests poor diversity in a community and a less healthy different between the different seasons [10]. Distribution of ecosystem. In this study, Shannon index of phytoplankton ranged Cyanobacteria is fundamental importance for the dynamics and from 1.84 to 2.48. Due to change of seasons and factors such as structure of aquatic communities [6] that the dynamic of rapid temperature change (change of seasons), high concentrations of increase or decrease of plankton populations is an important issue dissolved nitrogen in all of these examples can effect on the in marine ecology. This problem poses a challenge for ecologists, cyanobacteria, and then in different seasons are different. as the location of a production layer is not fixed [7], but rather Maximum density showed in atumn (285.7 ± 137.1) (m3) and depends on many internal parameters and environmental factors Maximum biomass showed (105.81 ± 38) (mg/m3) in the summer [11], and even with respect to daily time that Cyanobacteria are a that various factor, including different rates of reception, sun phytoplankton too. Cyanobacteria are very similar to bacteria, energy, consequently temperature, Water flows and river water in meaning they lack a distinct nucleus and differentiated this area can cause cyanobacteria to differentiate at different cytoplasmic attachments and differ in their pigmentation, times. Cyanobacterial strains exhibit different levels of meaning that the cyanobacteria have pigments and the bacteria Pubtexto Publishers | www.pubtexto.com 3 J Marine Biol Environ Sci

Citation: Valentina P, Valerian N, Razvan B (2020). Study on Cyanobacteria Population in Iranian Waters of the Caspian Sea during 2010-2011. J Marine Biol Environ Sci 2(1): 107 DOI: https://doi.org/10.36266/JMBES/108 susceptibility to contamination. In most cases, the presence of 16. Janssen EML. Cyanobacterial peptides beyond microcystins A contamination increases the growth of cyanobacteria, indicating review on co-occurrence, toxicity, and challenges for risk that these microorganisms are more likely to decompose and assessment. Water Res. 2019; 151: 488-499. utilize these compounds [19]. The present study showed that the 17. Sze P. Biology of the algae. W.M.C. Brown publishers. 1986; 251. 18. Tahami FS. 2014. Study on species diversity, distribution, biomass diversity and number of cyanobacteria present in the ecosystem of and bloom of cyanobacteria in Southern Caspian Sea. 2014. 2nd the southern Caspian Basin varies in different seasons and International Conference on Oceanography. J Marine Sci Res Dev. different season conditions including climatic conditions, 2014; 70. moisture content and amount of light absorbed on the surface are 19. El-Sheekh MM, Hamouda RA, Nizam AA. Biodegradation of crude involved. oil by Scenedesmus obliquus and Chlorella vulgaris growing under heterotrophic conditions. Int Biodeterioration Biodegradation. 2013; References 82: 67- 72. 1. Hmimina G, Hulot FD, Humbert JF, Quiblier C, Tambosco K, et al. inking phytoplankton pigment composition and optical properties: A framework for developing remote sensing metrics for monitoring cyanobacteria, Water Res. 148. 2019; 504-514. 2. Tahami FS, Pourgholam R, Therriault AR. Changes in phytoplankton community structure in Southern Caspian Sea, Comparison of phytoplankton before and after M. leidyi invasion in Caspian Sea, LAP LAMBERT Academic Publishing. 2012; 228. 3. APHA (American Public Health Association). Standard Methods for the Examination of Water and Wastewater. 17th edition, APHA, AWWA and WPCF, Washington D.C; USA. 2005; 150. 4. WHO. Toxic Cyanobacteria in Water AGuide to their Public Health Consequences, Monitoring and Management. Geneva World Health Organization. 1999; 5. Shannon CE, Weaner W. The mathematical theory of communication. University of Illinois Press, Urbana. 1949. 117. 6. Balch WM. An apparent lunar tidal cycle of phytoplankton blooming and community succession in the Gulf of Maine. J Exp Marine Biol Ecol. 1981; 55: 65-77. 7. Demers SL, Legendre JC. Therriault. Phytodistribution of phytoplankton. Bull Marine Sci. 1986; 43: 710-729. 8. Hsiao SIC. Quantitative composition, distribution, community structure and standing stock of sea ice microalgae in the Canadian Arctic. Arctic. 1980; 33: 768-793. 9. Battish SK. Fresh water zooplanktons Of India, Oxford and IBH Publishing Co. Ltd. New Delhi. 1992; 10. Cullen JJ. Horrigan SG. Effects of nitrate on the diurnal vertical migration, carbon to nitrogen ratio and the photosynthetic capacity of dinoflagellate Gyrnnodiniurnsplendens. Marine Biol. 1981; 6231- 6289. 11. Hsiao SIC. Spatial and seasonal variations in primary production of sea ice microalgae and phytoplankton in Frobisher Bay, arctic Canada. Marine Ecology-Progress Series. 1988; 44: 275-285. 12. Khenari GA, Wan WO, Maznah Kh, Yahya Sh, Najafpour GHD, Najafpour M, et al. Seasonal Succession of Phytoplankton Community Structure in the Southern Part of Caspian Sea. American-Eurasian J Agric Environ Sci. 2010; 8146-155. 13. Paerl HW, Otten TG. Harmful Cyanobacterial Blooms: Causes, Consequences, and Controls. Microb Ecol. 2013; 65: 995-1010. 14. Pobel. Influence of sampling strategies on the monitoring of cyanobacteria in shallow lakes: Lessons from a case study in France. Water Res. 2011; 45: 1005-1014. 15. Ganjian KHA, Wan WO, MaznahKH, Yahya SH, Najafpour DGH, Najafpour A, et al. The assessment of biological indices for classification of water quality in southern part of Caspian Sea. World Apply Science J. 2009; 7: 1097-1104.

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