Identification and density of ichthyoplankton in Laft Creeks (Hormuzgan province)

During a series of Ichthyoplankton survey from May 1998 to April 1999 Ichthyoplankton samples were collected at 12 stations in Laft creeks by 500 micron bongonet with oblique towing from bottom to water surface. Twenty-two families Ichthyoplanktons were identified (and two unidentified) during 12 months. Clupeiidae (31, 32%), gobiidae (26, 71%), scianidae (16, 55%), leiognathidae (11, 9%) were common and dominant families in all sampling stations. The creeks was divided in two branches: In east branch gobiidae (44.75%), clupeiidae (17.42%), scianida (13.5%) were more abundant than other families and in west branch clupeiidae (34.22%), gobiidae (23.77%), scianidae (16.34%) showed leiognathidae (13.26%) more abundance than other families, too. Some families e.g hemiramphidae, engrauilidae, blenidae, bothidae only occur in west branch, pleuronectidae family only occur in west branch. The highest density was found in winter season

A survey of algal bloom impacts on abundance and distribution of macro benthos in Hormozgan province coastal waters

The investigation of the algal bloom effects on Macro benthos abundance and diversity was seasonally carried out in coastline waters of Hormozgan province in 1391. Fourteen stations were selected for sampling; as 8 stations in coast of Bandar Abbas, 3 in Jask Port (east of Hormozgan) and 3 stations in Lengeh Port (west of Hormozgan). Polychaets, oligochaets, mollusks, crustacean and others like nematodes, nemertean’s, foraminifera’s, and ophiuroides were identified. Crustacean with 333950 ind.^-2 were dominant group whereas nemertean with 5050 ind.^-2 were minimum in density. Results showed that mean abundance of macro benthos was at most in spring (5614±3992 end) ^-2 and with 1244±380 ind.-2 was at least in autumn. Related results to stations showed that mean abundance in Jask Port and Lengeh Port were more than Bandar Abbas City. Among 8 stations in Bandar Abbas, Langargah with 168±977 ind.^ -2 was at most and Posht-e- shahr was at least in abundance (82±256 ind. ^-2). In Lengeh and Jask ports the stations far from coasts showed more abundance than station near coast. Monthly investigation showed that Macro benthos community was much more in April with 1011±6783 ind.-2 than December with 6±28 ind.^-2 , respectively. Shannon -Winner diversity index was low (0.61.2) in three stations, Evenness ranged from 0.1 to 0.4 and Margalof ranged from 2 to 4. Among four stations, mean wet weight varied from 12.18±6/95 gr in Jask Port (maximum) to 6.24±3/85gr in Bandar Abbas (minimum) .Seasonally, in spring the wet weight of macro benthos was 15.15±16/32 (maximum) and with 1.43±0.88 gr showed the minimum value in summer. There was a negative correlation between silt and macro benthos abundance and a positive correlation existed between macro benthos community and sand. There was no significant correlation between macro benthos community and TOM. To pay attention to results like diversity, abundance, wet biomass and correlation; it seems that algal bloom has no obvious negative effect on Macro benthos communities

Determination of effective parameters on growth and bloom forming of Cochlodinium polykrikoides

Harmful algal blooms resulting in red discoloration of coastal waters in the Persian Gulf, Iran were first observed in January 2007. The species responsible for the bloom, which was identified as Cochlodinium polykrikoides, coincided with massive aquatic organisms’ mortalities in the Persian Gulf. In order to provide optimum growth and bloom forming, C. polykrikoides cells were sampled during the bloom conditions in the coastal waters of Persian Gulf. After adaptation in filtered seawater, they isolated by positive phototropism characteristic of this species to light. They were grown in modified media culture at different salinity (30, 32 and 35ppt), temperature (20, 23, 26 and 28ºC) and intensity (35, 70 and 90 µmol m^-2 s^-1) with an initial cell density of 50 cell mL^−1. The results of the present study clearly showed that the highest alga biomass was obtained following culture by using A^2 medium under the 32ppt salinity, 26°C temperature, and under a 11h light:13h dark photoperiod regime at a light intensity of 90 µmol m^-2 s^-1 provided by cool white fluorescent tubes. Mean cell density of C. polykrikoides in a 60 liter tank for ten days reached to 32 × 10^6 cell L^−1. Moreover, individual C. polykrikoides chain with 18 cells was observed for the first time in cultures. Based on the results from the present study, as mentioned above, providing suitable media culture and physical condition (light intensity and temperature), bloom forming of C. polykrikoides start from day 8 to 10 and will be continued until day 24 t0 28. In the other hand, C. polykrikoide cells immediately crashed and destroyed

A survey on planktonic communities in Bandar Abbas coastal area

This study was conducted for investigation on algae bloom monitoring and oscillations of biotic and non-biotic parameters in coastal waters of Bandar Abbas from October 2013 to Septembre 2014. In this project, planktonic distribution and environmental data were collected from five stations, every 10 days. Four order and 45 genus of phytoplankton (Bacilliarophycea 29 genous, Dinophycea 13 genus, Cyanophycea 2 genus, Raphidophycea 1 genus) were identified, as well as , 10 order of zooplanckton consisted of Copepoda, Mollusca, Chaetognatha, Sarcomastigophora, Urochordata, Annalida, Nematoda, Echinodermata, Ciliophora and Granuloretica. Results showed that Bacillariophycea were dominate among phytoplankton species in all season. So that, Leptocylindrus, Chaetoceros and Nitzschia from Bacillarriophycea, Protoperidinium and Gymnodinium belong to Dinophycea, and Oscillatoria belong to Cyanophycea were dominate genus in Bandar Abbas coastal waters. The maximum and minimum density and frequency for phytoplankton were recorded respectively from Shilat Jety and Airport Stations. Based on ANOVA analysis on phytoplankton density no significant were observed seasonally (p>0.05), but significant differences were observed between stations (p<0.05). Algal blooms were recorded for Protoperidinum, Chaetoceros and Noctiluca form Shilat Jety in the study period. Result showed that Crustacea have more density amongst zooplankton community, although Arthropoda were dominate in all season. The maximum frequencies were recorded for Nauplius (78%) and Copepoda (21%), also Among copepod, Calanoida order observed 68.5% frequency in the study period. The ANOVA analysis showed significant differences both in stations and seasons for zooplankton density (p<0.05). The seasonal range of temperature were recorded between (19.43±2.58 - 31.98±2.48 ), salinity (27.15±9.48 - 38.13± 0.72ppt), dissolved Oxygen (2.8±1.81-6.87±1.25) mg/L, and pH (8.06±0.49- 8.69±0.23). Evaluation of biotic and abiotic factors indicate the probability of unhealthy and unstable Shilat jety and Gorzoozan stations coastal waters of Bandar Abbas City. One of these cases can be mentioned to high density of cyanophyceae in the estuary Gorzoozan compared other stations , high density of Phytoplankton and low diversity in the Shilat station. While the increase in Harpacticoida order of copepods As an indicator of pollution than on previous reports of other researchers In the this area, suggests pollution is pushed into the area