The seasonal fluctuation of Cyanophyta in the southern Caspian Sea

The objective of this study was to evaluate the seasonal fluctuation of density and biomass of cyanophyta in different water temperatures in the southern Caspian Sea in 1996 and 1999-2000. 432 samples of phytoplanktons were collected from 18 stations in coastal zone (depth less than 10 m). As a result, 11.1% (9 species from 81) and 15.6% (25 species from 160) of total phytoplanktons were cyanophyta in years 1996 and 1999-2000, respectively. The maximum density and biomass (1.65x106/m3 , 4.09 mg/m3) of Cyanophyta were found in the western region and in warm seasons (spring and summer). On the other hand, in cold seasons (autumn and winter), the maximum density and biomass (1.5x105fm3, 3.36 mg/m3) were found in the eastern part of the Caspian Sea. In years 1999-2000, the maximum biomass and density of Cyanophyta were found in eastern, central and western parts of the Caspian Sea in spring and summer, meanwhile in autumn and winter, they were found with maximum density and biomass in the eastern part. In all seasons, the minimum and maximum water temparture were measured in the western part and eastern part of the southern Caspian Sea, respectively. The results showed that the most density of cyanophyta were measured in summer that can be related to the increase of temperature and daylight. The non-parametric statiscal analysis indicated that there were no significant difference between biomass and density of cyanophyta in years 1996 and 1999-2000. As a conculsion, the population dynamic of cyanophyta were mostly affected by combination of enviromental factors than effect of a single factors sperately (such as temperature)

Physical and chemical factors determination of Mohammadiye Channel water for aquaculture purposes

In this survey the Physical and Chemical factors were studied in mohammadiye channel extending Eslamshahr, Robat karim and Shahriar cities of Tehran Province during the 2011 in agriculture period (May, June, July, August, September, October) Sampling were done from 5 different stations. The measured factors were temperature,DO, Cl,HCO3,COD,BOD,CO2,Mg,… The analysis of Physical and Chemical factors of Mohammadiye channel water showed that except water temperature, all factors in comparison to the standards were at the standard level, So they are suitable for aquaculture. Due to mean of water temperature that is high from middle of Spring to the end of summer, It is suitable for culture of warmwater fishes and because of low water temperature in the station No1 It is recommended for culture of coldwater fishes by using of 50-70gr of young fishes

Shells of Bufonaria echinata as biomonitoring materials of heavy metals (Cd, Ni and Pb) pollution in the Persian Gulf: with emphasis on the annual growth sections

Concentrations of heavy metals (Cd, Ni and Pb) were determined in soft and hard tissues (three separated shell sections) of gastropod Bufonaria echinata as well as surficial sediments collected in October 2015 from two sampling sites located in the sub-littoral zone of Qeshm Island, Persian Gulf. There were significant differences between the sampling sites for concentrations of all the three elements in the shells and sediments. But in terms of the soft tissues, in the case of Ni and Pb significant differences between the sites could be observed. In all the cases, higher levels were observed in the samples from Suza site, which may be mainly due to the proximity of this site to the relevant anthropogenic sources. Comparison of the gained data from this study with the other relevant researches shows that in most cases the levels of the elements in the soft tissues and shells either fell within the range for other world areas or were lower. The observed increasing trends of metals accumulation in the shell sections (from older to younger sections) could be mainly attributed to the gradual increase of relevant anthropogenic pollutants in the study area, especially in Suza pier, during the recent years. Generally, it can be concluded that the shells of B.echinata could be possibly employed as a biomonitoring tool for historic metals contamination in northeastern part of the Persian Gulf

Physicochemical characteristic of Penaeus indicus ponds in coastal area of Gorgan Bay (Mazandaran province)

A series of studies were conducted to evaluate the possibility to culture Penaeus indicus in coastal area of Gorgan bay concerning the proper climate potential of Behshahr zone during summer till autumn 2000. Thirty two water samples were collected from four shrimp ponds for further laboratory studies to measure some physicochemical parameters such as: temperature, pH, salinity, transparency, nitrogen, phosphorus, D.O. according to the Russian Standard (1988). As a result, the range of water temperature, pH, salinity and trasparency were 24.5-29.0°C, 8.02-8.18, 31.5-43.5 ppt and 21-50cm, respectively and the fluctuation concentration of D.O, NH^+4, NO^-2, PO4^-3 were 3.8-9.5 ml/l, 0.0022-0.015, 0.0021-0.1210 and 0.0145-0.3710 mg/l, respectively. As a conclusion, this shrimp species can be easily adopted with different climate, so this region is suitable for shrimp culture as view point of temperature and salinity. For demonstration of this issue, the semi-intensive shrimp culture has been successful. Also the toxic material such as ammonia and nitrite did not show any restriction for shrimp culture

The study of pollution in the Gorgan bay

From an environmental standpoint bays around the world are very important ecosystems including the Gulf of Gorgan Bay and thus are important. Which has a relatively low depth, a little flow, temperature appropriate, biogenic materials and abundant food in the sea suitable for children sometimes place (Nursery ground) and also the perfect place for power (Fattening ground) is an early sea fish. In this research effort will be the initial studies on the impact of environmental pollutants on the ecosystem of the Gulf of Gorgan and the quality and quantity of pollution, especially pollution, agricultural pesticides and entering the Gulf of Gorgan and the impact on the ecosystem's the initial assessment and the monitoring of changes in them over the years. The user in the Gulf of Gorgan, agriculture. Pollution from agricultural fields related to pesticides and fertilizers are used in the fields. According to consumer research, and the remaining amount of pesticides in water and sediments of the Gulf of measured, indicated that most of the remains of chlorinated pesticides in sediments of the pesticides used in the agricultural sector In addition, all the toxins in the summer and spring peak. In addition, the DDE concentration compared to other poisons. In the case of other contaminants in the area is now threatened by the Gulf of Gorgan, although not serious, but it seems that the increase in organic matter and reduce the amount of oxygen of the water. The near future to Eutrofication risks in the ecosystem

A survey of feeding habits of economic benthic feeder fishes in the southern of Caspian Sea (Rutilus frissi kutum, Rutilus rutilus caspicus, Cyprinus carpio, Liza auratus and Liza saliens)

Present study analyzed the stomach contents of individuals belonging to five fish’s species in order toInvestigate seasonal changes in feeding strategy and diet composition in the South coast of the Caspian Sea (Gilan and Mazandaran provinces) from late March until late May 2010 using the research ship Gillan and fishing with batoom trawl nets and fishing blades insoles bony fishes in the depths of less than 60 meters. The average length and the total weight of Rutilus frisii kutum, Rutilus rutilus caspicus, Cyprinus carpio, Liza auratus and Liza saliens respectively were 36/9 ± 8/5 cm , 562/9 ± 353/2 g, 23/2 ± 3/2 cm , 202 ± 101/6 g, 24/6 ± 8/1 cm , 249/8 ± 242 g, 32/2 ± 8/9 cm , 320/9 ± 242/8 g, 22/7 ± 2/6 cm and 82/9 ± 52/2 g repectively. Using the method of Shorygin and Costello highly nourishing food strategy and different species of fishes were studied. The results of this study showed that Rutilus frisii kutum fed generally of Balanus and Cerastorderma In order of importance after Bivalvia, Gastropoda, Crabs, Fish eggs, Filamentous alge in GI Rutilus frisii kutum presence, but feeding it of Bivalvia (in particular Cerastorderma) was much more than the other food. The results of present study showed that under the influence of compatibility and behavioral mechanisms, ecological, physiological and nutritional importance of Rutilus frisii kutum Bivalvia. The results of studies were showed that Bivalvia was feeding the dominant Rutilus frisii kutum , while the results of this study showed that despite Bivalvia present importance in feeding the of this species, it seems that its presence in such digestion decreased. As well as the dominant food of Rutilus rutilus caspicus was fish, but generally from Detrite fed. This study showed that feeding the dominant species of Cyprinus carpio, Liza auratus and Liza saliens of Detrite was. The most important food items after ditrit for the Cyprinus carpio in order of importance include the Bivalvia, Gastropoda, Oligochaeta, Abra ovata, Nereis, Fish eggs, Filamentous alge, was. The Liza auratus dietary habits also showed that after ditrit the most importance in nutrition related to Foraminifera, Porifera and Balanus, and for Liza saliens to Gastropoda, Bivalvia and Porifera. The results showed that the mullet the greater the intensity of feeding fishes than other species were, Rutilus frisii kutum in between of Cyprinidae the greater the intensity of feeding fishes than other species were (0/05 > P). The values of this indicator in the lower longitudinal in all fish species investigated were more than high longitudinal groups. The feeding intensity at different times of sampling for all species investigated showed that in all species at times extremely reduced the reproductive index (0/05 > P). As well as the diversity foods in the lower longitudinal in all fish species investigated were more than high longitudinal groups. In conclusion, our results demonstrated Food strategy have changed based on physiological changes, metabolism activity, behaviour, and the amount of food available

The study of physico-chemical characteristics, heavy metals and plankton of water in the warm water fish ponds using organic (cow dung) and chemical fertilizer

Currently, different kinds of chemical fertilizer such as urea, nitrate, sulphate and ammonium phosphate–potash are using in fish ponds of carp (Hypophthalmychthysmolitrix, Hypophthalmychthysnobilis). Chemical fertilizers, especially phosphate fertilizers can cause environmental pollution. Therefore, the use of alternative one, particularly organic fertilizer (manure) can reduce environmental issues. This study is conducted to effects of liquid cow manure on abundance, biomass and community structure of phytoplankton, zooplankton, physico-chemical chractrestics and heavy metal of water in the warm water fish ponds. For this purpose, the effects of three different types' fertilizers have been searched on fish ponds water. The ponds number 1 and 3 treated by chemical fertilizer and liquid cow manure respectively. Both of the two fertilizers (liquid cow manure and chemical fertilizer) were used in the pond number 2. Results showed that acidity of liquied cow manure was low (pH=7-8), however the total hardness and alkalinity were high. Meanwhile, percent of nitrogen were more than percent of calsium and phosphorus liquid cow manure. The concentrations of Pb, Fe and Zn elements were higer than critical level but some of them such as Cd, Cr, and Hg were lower than detection limit. As a conclusion, biomass of phytoplankton, zooplankton and physico-chemical parameters in fertilized pond treated by liquid cow manure were more convinence than pond treated by chemical fertilizers

Production of bacterial probiotic from trout (Oncorhynchus mykiss) for improvement of immune system and challenge to streptococcosis

This study was conducted for the first time and the effects of probiotic bacteria isolated from the gut of Rainbow trout (Oncorhynchus mykiss). In the first step, after the purification of the isolated bacteria, probiotic properties in vitro was assessed with injection to healthy fish and challenge with three species of pathogenic bacteria in culture media. The second phase of the bacteria isolated in 5 treatments (log 7, 8 and 9 of the lactic bacteria (LAB), Vibrio sp and Pseudomonas sp) and a control treatment on growth and survival, hematological parameters (RBC and WBC cells), immunology and physiology parameters tested during the 60 days of the above parameters after 30 and 60 days and finally at the end, the final assessment was Streptococcosis resistance in fish. The results showed that the isolated bacteria were able to enhance the growth parameters (weight, feed conversion, feed fat, protein efficiency ratio and specific growth rate) and survival. The results showed that log 8 LAB was significant difference with other treatments and control. When using log 8 LAB and Vibrio, the MCV, MCH and MCHC were decreased with no significant difference. The log 8 has the greatest effect on the amount of liver enzyme (AST), IgM and complement component C3, and had significant difference with other treatments. The challenge examination to Streptococcus iniae showed the highest survival in treatments with log 8 (96.66%), and Vibrio (93.33%) and then subjected to other treatments and control are also the least survival (25.38%). The conclusion of that study is the first probiotic properties of bacteria isolated from trout to changes in quality indicators are in particular the LAB bacteria and the second log 8 of LAB had significant positive of changes development and safety, and the fish are resistanted against Streptococcosis

Study on macrobenthic communities in the range of fish cage-culture area (before breeding) in the southern Caspian Sea (Mazandaran coast-Kelarabad)

The abundance and biomass of benthic macroinvertebrates were studied in the place of fish cage culture in southern coasts of Caspian sea (Mazandaran waters- kelarabad). The goal of this study was to consider of fish cage culture effects on the abundance and biomass of benthic macroinvertebrates. The sampling was carried out in 3 stations in depth of 20 meter of Kelarabad waters monthly. In this study 7 species were identified belonged to 5 genus of 4 family. Totally 23442 sample of benthic invertebrates were counted that the lowest and highest abundance were in station 1(23.4%) and station 2(46.8%) respectively. The results of stations study showed that the highest abundance and biomass were in stations 2 and 3 with the average of 646 ± 1230.4 n/m^2 and 0.526 ± 1.001 gr/m^2 respectively. This coulld be respectively dependant to not settling of cage (witness station) and appearance of Cerastoderma glaucum because of its large body in station 1. The difference of abundance and biomass between different stations was not significant (p ›0.05). The study on abundance and biomass in different seasons showed that the highest abundance in autumn with the avarage of 888.13 ± 1371.58 n/m^2 belonged to Strblospio gynobranchiata and the highest biomass belonged to C. glaucum which was because of appearance of not native species of polychaeta and also the species with shell covering from bivalvia. The results showed that the specie of S. gynobranchiata from polychaeta including 93.3% of abundance was the dominant specie that could be related to appropriate ecological conditions for living and high adaptability. It was concluded that the abundance and biomass of benthic macroinvertebrates in station 1 was lower than other stations which was related to fish cage culture activity and its effects on benthic macroinvertebrates. So it is suggested that each mariculture activity in southern coasts of Caspian Sea should be carried out with regarding to environmental considerations and performance of comparative evaluation project of environmental effects

The study of abundance and dynamic zooplankton in the Southern of Caspian Sea

The Caspian Sea is the largest lake, both by its area and volume. Zooplankton are very important in the food web since many animals eat them. The Sampling was done in 4 transacts in Anzali, Tonekaboun, Noushahr and Amirabad at 3 different depths including 5, 10 and 20 m. Sampling was carried out in four seasons of spring, summer, autumn and winter in 2013. The annual changes of zooplankton was between 392±113 ind./ m^3 in autumn (Amirabad) to 8065±11735 ind./m^3 in winter (Amirabad). The lowest density of zooplankton in the spring was 2207 ind./ m^3 in Anzali. The density of zooplankton in Tonekabon and Amirabad was 2.0 and 2.8 fold more than other transects respectively. The results showed that the abundance of zooplankton in summer was between 1964±470 ind./m^3 (Amirabad) to 5706±6088 ind./m^3 (Tonekabon). The biomass was 30.02, 52.22, 22.98 and 18.31 in Anzali, Tonekabon, noshahr and Amirabad respectively. The abundance of zooplankton in the autumn reached the lowest value. The lowest value was 392 ±113 ind./m^3 and 3.71±0.19 mg/m^3 (Amirabad) and highest value was 2280 ±1435 ind./ m3 and 20.23±14.50 5mg/m^3 (Anzali). The highest density was observed in Amirabad (8065 ind./m^3) and Anzali (8061 ind./m^3) in winter. The aim of this study was diversity, distribution, density and biomass of zooplankton in the southern of Caspian Sea