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Appendicularians are the most important group among zooplankton communities, widely distributed in all the oceans and they are considered as one of the most important sources of productivity and food supplies for secondary consumers. So this study aimed to identify, introduce and assess the temporal and spatial variations of the Appendicularians in the Persian Gulf, restricted to coastal waters of northern part of Bushehr. Appendicularians were collected during seven sampling programs, from Frake river-estuary, three sites of large creek-estuary of the Shif, one site in the sea, and one site in the Lashkari creek-estuary, at middle and last day of each season, midsummer of 2016 to spring of 2017. During all surveys, depth of the sampling location, Secchi depth, water temperature, pH, and salinity were measured. Finally, 4 species were identified, Oikopleura dioica, Oikopleura longicauda Appendicularia sicula and Fritillaria sp. The highest total density was observed in the sea station at March, with dominance of O. dioica and a relative abundance of 80%, relative abundance of O. longicauda, A sicula andFritillaria sp.were calculated 18.9%, 1.06% and 0.04% respectively, so Fritillaria sp were introduced as rare species. Two species of O. dioica andO. longicauda demonstrated completely different spatial and temporal distribution pattern, and based on dbRDA (distance based Redundancy Analysis), transparency explains effectively the distribution pattern of O longicauda, and alsodepth and salinity are the most important factors which explain the distribution pattern of O dioica and temperature was correlated factor with abundances of A sicula, in our study area.

This study was carried out to determine the water environmental parameters as risk factors for rainbow trout breeding and rearing farms in the Haraz River. 84 water samples were collected at 6 stations during seven months in 2017-2018. Water samples were analyzed by standard titration and spectrophotometry. Results showed that the range of water temperature (4.0-17.0◦C), weather temperature (5.0-28.0◦C), dissolved oxygen (7.36-14.24 mg/l), BOD5 (0.20-20.80 mg/l), COD (3.50-41.40 mg/l), electro-conductivity (345-650 µS/cm), turbidity (2-81 NTU), TSS (0.01-0.72 g/l), pH (6.98-8.15), TP/P (0.01-0.15 mg/l), PO43- (0.01-0.20 mg/l), NH4+ (0.02-0.31 mg/l), NH3 (0.14-4.36 µg/l), NO2- (0.01-0.21 mg/l), fecal coliform (9-30000 CFU/100ml) and water quality index (48.5-98.5) were changed. The results of the stepwise regression analysis indicated that the risk factors of water quality in the Haraz River were fecal coliform, phosphate, turbidity, and BOD5 parameters, and fecal coliform had a higher coefficient factor (beta coefficient) than other parameters (p

Phycocyanin is a blue pigment of Spirulina algae that has antioxidant, anticancer and anti-inflammatory properties. In this study, primary culture of Spirulina was performed in the modified Zarrouk medium. Phycocyanin was extracted enzymatically using lysozyme and was purified by the use of ammonium sulfate 40% solution. The stability of phycocyanin was evaluated by the split factorial experiment in a completely randomized design based on three factors including temperature (-18, 4 and 10°C), pH (4.5, 5.5 and 7) and time (15, 30 and 45 days). The concentration and purity of phycocyanin in the crude extract were 1.815 mg/ml and 0.825, respectively whereas the concentration and purity of phycocyanin in the purified extract were 3.751 mg/ml and 1.135, respectively. The results showed that the stability of phycocyanin was relatively decreased by increasing the storage time at various temperatures. However, the highest stability of phycocyanin was observed at -18°C followed by 4°C with the same trend in the range of pH. By increasing the storage temperature to 10°C, the stability of phycocyanin drastically reduced especially in a pH of 5.5 and the absorbance of light was reached to zero in 30 days. The best conditions for the minimum concentration loss of phycocyanin were in a pH of 4.5 at -18 °C and storage duration of 30 days. According to the results, it is possible to use phycocyanin in the food products that are stored in cold or freezing temperatures such as dairy products and ice cream.

The Shahid Rajaei Reservoir constructed for various purposes such as drinking water supply. In this context, and also because of the importance of the bloom events and eutrophication process in dams, this paper is to survey the relations between some of physicochemical parameters and phytoplankton composition and density, chlorophyll-a and some water quality indices (Trophic, Saproby, Shannon) using mono and multivariate statistical analysis. Water samples collected from 4 stations during May, June, July, August, September, November and February in 2012-2013. According to the results, the maximum concentration of dissolved inorganic nitrogen, chlorophyll-a, phytoplankton abundance, trophic and saproby indices observed in a month of summer which it was accompanied to the minimum value of species diversity index (Shannon). Pearson analysis revealed direct correlation between abundance of Goniaulax polyedra, Goniaulax digitale and trophic index. In the other words, higher abundance of the two species decreased the water quality. Also based on the PCA analysis, the significant correlation observed between abundance of Cyclotella meneghiniana with Shannon and saproby indices which were negative and positive, respectively. This result indicates to the relation of degradation of water quality with increasing the abundance of Cyclotella meneghiniana. Meanwhile, the presence of the three parameters (abundance of Cyclotella meneghiniana, Shannon and saproby indices) in first component of PCA indicated the important role of Cyclotella meneghiniana and two biological indices in determining of water quality in Shahid Rajaei Reservoir.

Seasonal variation and vertical distribution of water temperature, pH, electrical conductivity, dissolved oxygen and chlorophyll-afrom the Iranian waters of Hormozgan province in the Persian Gulf were studied from February 2001 to February 2002. All parameters were measured by using CTD multiparameter probes at 30 sampling stations. Data obtain revealed that seasonal thermocline appears in the survey area during spring, extended in summer, diminishes in autumn and gradually eliminate during winter season. Variation in electrical conductivity follows the changes in winter temperature throughout the year except in winter. Dissolved oxygen was recorded to be higher in the depth layer of 10-25 meters and decreases by increasing depth. Vertical pH of water indicated a decreasing pattern from surface to bottom throughout the year, with highest decrease in autumn, when the dissolved oxygen decreases as well. The maximum concentration of chlorophyll-a was recorded at depth layers of 20-40m and 10-20m during first and second half of the year, respectively.