Variations of Temperature and Salinity in the Southwestern Coastal Waters of the Caspian Sea, North of Iran

2014 ◽  
Vol 2 (2) ◽  
pp. 13
Author(s):  
Marzieh Yousefi ◽  
Kamran Lary
Keyword(s):  
Coastal Waters ◽  
Caspian Sea ◽  
The Caspian Sea ◽  
North Of Iran

THE NUMBER AND QUALITATIVE CHARACTERISTICS OF FRY FISH IN SHALLOW COASTAL WATERS OF THE VOLGA IN THE SUMMER-AUTUMN PERIOD OF 2012

2017 ◽  
pp. 65-73
Author(s):  
Edward Vladimirovich Nikitin
Keyword(s):  
Fish Species ◽  
Coastal Waters ◽  
Caspian Sea ◽  
The Caspian Sea ◽  
Volga River ◽  
Commercial Fish ◽  
Autumn Period ◽  
Fish Juveniles ◽  
Qualitative Characteristics ◽  
Shallow Coastal Waters

Shallow coastal waters of the Volga river is a flooded feeding area for fish juveniles of nonmigratory fish species. There takes place annual downstream migration of fluvial anadromous fish species from spawning grounds of the Volga river to the Northern Caspian Sea. The most important factors determining the number and qualitative characteristics of fry fishes are the level of the Caspian Sea (currently having a tendency to the lowering), hydrological and thermal regimes of the Volga river. Researches were carried out in definite periods of time. In the summer-autumn period of 2012 fry fishes were presented by 19 species (13 of them were commercial species), which belonged to 9 families. The article gives data on all the commercial fish species. In the first decade of July the maximum number of fry fish was registered in the western part of the Volga outfall offshore - in box 247 (19.86 mln specimens/km2), in the eastern part - in box 142 (20.4 mln specimens/km2). The most populous were roach, red-eye, silver bream and bream; size-weight characteristics were better in the areas remoted from the Volga delta. In the third decade of July the quantitative indicators of fry fish on these areas decreased, size-weight characteristics greatly increased. In the second decade of October in the western part of the seaside there were registered increased pre-wintering concentrations of fish juveniles, their qualitative indicators increased, which is evidence to favorable feeding conditions in 2012.

Trace element accumulation in fishes collected from coastal waters of the Caspian Sea

2005 ◽  
Vol 51 (8-12) ◽  
pp. 882-888 ◽  
Author(s):  
Yasumi Anan ◽  
Takashi Kunito ◽  
Shinsuke Tanabe ◽  
Igor Mitrofanov ◽  
David G. Aubrey
Keyword(s):  
Trace Element ◽  
Coastal Waters ◽  
Caspian Sea ◽  
The Caspian Sea ◽  
Element Accumulation ◽  
Trace Element Accumulation

scholarly journals Numerical simulation of rainfall with assimilation of conventional and GPS observations over north of Iran

2016 ◽  
Vol 59 (3) ◽  
Author(s):  
Mohammad Ali Sharifi ◽  
Majid Azadi ◽  
Ali Sam Khaniani
Keyword(s):  
Relative Humidity ◽  
Caspian Sea ◽  
Model Simulation ◽  
Global Analysis ◽  
Three Dimensional ◽  
Wrf Model ◽  
Precipitable Water ◽  
Absolute Error ◽  
The Caspian Sea ◽  
North Of Iran

<p>In this work, the effect of assimilation of synoptic, radiosonde and ground-based GPS precipitable water vapor (PWV) data has been investigated on the short-term prediction of precipitation, vertical relative humidity and PWV fields over north of Iran. We selected two rainfall events (i.e. February 1, 2014, and September 17, 2014) caused by synoptic systems affecting the southern coasts of the Caspian Sea. These systems are often associated with a shallow and cold high pressure located over Russia that extends towards the southern Caspian Sea. The three dimensional variational (3DVAR) data assimilation system of the weather research and forecasting (WRF) model is used in two rainfall cases. In each case, three numerical experiments, namely CTRL, CONVDA and GPSCONVDA, are performed. The CTRL experiment uses the global analysis as the initial and boundary conditions of the model. In the second experiment, surface and radiosonde observations are inserted into the model. Finally, the GPSCONVDA experiment uses the GPS PWV data in the assimilation process in addition to the conventional observations. It is found that in CONVDA experiment, the mean absolute error (MAE) of the accumulated precipitation is reduced about 5 and 13 percent in 24h model simulation of February and September cases, respectively, when compared to CTRL. Also, the results in both cases suggest that the assimilation of GPS data has the greatest impact on model PWV simulations, with maximum root mean squares error (RMSE) reduction of 0.7 mm. In the GPSCONVDA experiment, comparison of the vertical profiles of 12h simulated relative humidity with the corresponding radiosonde observations shows a slight improvement in the lower levels.</p>

scholarly journals MICROALGAE FROM THE COASTAL WATERS OF TYULENY ISLAND IN THE CASPIAN SEA

2019 ◽  
Vol 14 (2) ◽  
pp. 120-131
Author(s):  
R. M. Barkhalov ◽  
A. A. Abdurakhmanova ◽  
F. Sh. Amaeva
Keyword(s):  
Coastal Waters ◽  
Caspian Sea ◽  
Biomass Concentration ◽  
Water Area ◽  
Trophic Chain ◽  
The Caspian Sea ◽  
Standard Procedures ◽  
Water Surface Layer ◽  
Rich Flora ◽  
Positive Effect

Aim. In this work, we set out to study the composition of a phytoplankton community in an important fishery area, the coastal water area of Tyuleny Island in the Caspian Sea.Methods. We present the results of seasonal observations (2016) on the state of phytoplankton in the coastal waters of Tyuleny Island in the Caspian Sea. In total, 120 phytoplankton samples were collected at four stations from the water surface layer (May–October) using the Nansen bottle and subsequent fixation by Lugolʹs solution. Sedimentation and concentration were carried out using standard procedures. The samples were processed in the Nageotte chamber with a volume of 0.1 ml under a light microscope.Results. According to the research results (2016), 103 species and varieties of microalgae were found in the phytoplankton samples collected from the water area of Tyuleny Island. The microalgae were represented by four divisions: Bacillariophyta – 49 species, Cyano‐ phyta – 24 species, Chlorophyta – 23 species and Pyrrophyta – 7 species. The greatest species diversity of phytoplankton in the studied water area was noted during the autumn period (61 spe‐ cies). In general, phytoplankton was found to be distributed homogeneously throughout the coastal area of the island, with the biomass concentration not reaching 1 g/m3.Conclusion. In 2016, favorable hydrological and hydrochemical conditions for the development of microalgae were observed. The desalinated water around Tyuleny Island, which is well warmed in the summer and does not freeze in the winter, contributed to the development of rich flora. Although bi‐ omass values were not high due to the prevalence of small‐celled microalgae in phytoplankton, in general, it should have a positive effect on the development of subsequent links in a trophic chain, as well as promote an increase in the productivity of waters of the Northern Caspian Sea. 

scholarly journals The effects of stock enhancement of pikeperch (Sander lucioperca) in Iranian coastal waters of the Caspian Sea

2007 ◽  
Vol 64 (5) ◽  
pp. 973-980 ◽  
Author(s):  
Shahram Abdolmalaki ◽  
Iwona Psuty
Keyword(s):  
Coastal Waters ◽  
Caspian Sea ◽  
Stock Enhancement ◽  
Early Years ◽  
Predatory Fish ◽  
Market Demand ◽  
Sander Lucioperca ◽  
The Caspian Sea ◽  
Artificial Culture ◽  
Abundant Population

Abstract Abdolmalaki, S., and Psuty, I. 2007. The effects of stock enhancement of pikeperch (Sander lucioperca) in Iranian coastal waters of the Caspian Sea. – ICES Journal of Marine Science, 64: 973–980. Annual landings of pikeperch (Sander lucioperca) in Iranian coastal waters of the Caspian Sea in the early years of its exploitation, the late 1920s and early 1930s, reached some 3000 t. However, after 1935, catches declined drastically through overfishing, declining sea level, and the destruction of spawning grounds in the Anzali Lagoon. In 1990, Iran initiated a programme of artificial culture to enhance the local stock. The aim of the programme was and still is to restore the formerly abundant population of this predatory fish and to increase the profitability of the beach-seine fisheries of fishers who had stopped deploying gillnets, which pose a threat to the valuable species of sturgeon in the Caspian. Analysis of the age composition of pikeperch catches indicates that the use of beach-seines does not prevent overfishing of young pikeperch released as fingerlings in the same calendar year in which the fishing season started. No undersized fish are discarded back into the sea, because there is market demand for even the smallest fish, and a lack of communication exists between the programme beneficiaries and the management and research units. Some 15 years after it was initiated, the effectiveness of stock enhancement at a level of 4–6million fry per year remains uncertain.

Optimization and partial purification of a high-activity lipase synthesized by a newly isolated Acinetobacter from offshore waters of the Caspian Sea under solid-state fermentation

RSC Advances ◽  
2015 ◽  
Vol 5 (16) ◽  
pp. 12052-12061 ◽  
Author(s):  
Samira Moradi ◽  
Seyed Hadi Razavi ◽  
Seyyed Mohammad Mousavi ◽  
Seyed Mohammad Taghi Gharibzahedi
Keyword(s):  
Solid State ◽  
High Activity ◽  
Solid State Fermentation ◽  
Coastal Waters ◽  
Caspian Sea ◽  
Partial Purification ◽  
Extracellular Lipase ◽  
The Caspian Sea ◽  
Mesophilic Bacterium

A new aerobic mesophilic bacterium was isolated from the southern coastal waters of the Caspian Sea which substantially produced an extracellular lipase in solid-state fermentation using milled coriander seeds (MCS) as support substrate.

Oil pollution in the Caspian Sea coastal waters

2006 ◽  
Vol 26 (4) ◽  
pp. 347
Author(s):  
Ahmad Khatoonabadai ◽  
Ahmadreza R. Mohammadi Dehcheshmeh
Keyword(s):  
Coastal Waters ◽  
Caspian Sea ◽  
Oil Pollution ◽  
The Caspian Sea

scholarly journals Effects of the Invasive Ctenophore Species, Mnemiopsis Leidyi, on the Caspian Sea

2013 ◽  
Vol 15 (1) ◽  
pp. 117-126
Author(s):  
Zahra Khoshnood ◽  
Reza Khoshnood ◽  
Mehdi Ghobeitihasab
Keyword(s):  
Invasive Species ◽  
Coastal Waters ◽  
Caspian Sea ◽  
Habitat Destruction ◽  
Significant Decline ◽  
Ecological Impacts ◽  
Economic Losses ◽  
Mnemiopsis Leidyi ◽  
The Caspian Sea ◽  
Wide Range

ABSTRACT Human interventions on the Earth’s natural systems are evident even in remote regions of the Antarctic and rain forests deep within the Amazon. In addition to human-induced climate change and habitat destruction, an emerging anthropogenic threat to biodiversity is the drastic species re-distribution (the movement of species from one place to another due to human intervention) at a global scale. This creates fertile conditions for biological invasions which in turn cause substantial economic and ecological losses. These human-mediated invasions, often referred to as “biological pollution”, are a worldwide problem that is increasing in frequency and magnitude, causing significant damage to the environment, economy and human health. Bioinvasions have strong impact on biodiversity and ecosystem functioning and stability. They are ranked as the second most important threat to biodiversity (after habitat destruction) by the World Conservation Union. The Ctenophore, Mnemiopsis leidyi, is one of the invasive species that naturally lives in the Atlantic coastal waters of North America and South America, but discovered in Azov, Black, Caspian, North, Baltic and Mediterranean (north-eastern part) seas in early 1980s. It seems that the main factor of its redistribution was the ballast waters of ships. As an alien species, Mnemiopsis leidyi caused many alterations in the Caspian Sea ecosystems. The fact that it feeds on the eggs of native fish Clopeonella spp., has resulted in a significant decline of its population; Clopeonella spp. were the main source of industrial fishing in the Caspian Sea and also the main source of food for precious fish species, the sturgeons, and therefore, their decline has caused a huge economical loss for the area's inhabitants and a significant decline of sturgeon populations. This species has caused massive ecosystem changes and substantial economic losses in the late 1980s-1990s, and it has been recognized as a problem of main ecological concern for the sustainable development of the region, together with the high level of anthropogenic pressures on the Caspian Sea ecosystems. Some special characteristics of this species, such as adaptation to a wide range of salinity and temperature, high capability of reproduction, hermaphroditism and dissogeny, have led to huge increases of its mass, especially in southern regions of the Caspian Sea, the coastal waters of Iran. In addition, it has become clear that this species does not have any natural predators in the Caspian Sea, and also that it can feed on any organisms smaller than itself in size. Owing to these facts, it is a huge ecological threat for the Caspian Sea ecosystems. The aim of the present paper is to review the biological and ecological impacts of this invasive species on the Caspian Sea ecosystems.

Verbascum shahsavarensis (Scrophulariaceae), a new species for Flora of Iran

Phytotaxa ◽  
2015 ◽  
Vol 203 (1) ◽  
pp. 76 ◽  
Author(s):  
Arash SOTOODEH ◽  
Laure Civeyrel ◽  
Farideh Attar
Keyword(s):  
New Species ◽  
Endemic Species ◽  
Caspian Sea ◽  
The Other ◽  
Distribution Map ◽  
Flora Of Iran ◽  
The Caspian Sea ◽  
Coastal City ◽  
North Of Iran ◽  
A New Species

A new endemic species, Verbascum shahsavarensis, is described from north of Iran. Based on two unique characters of this species, these being two anterior longitudinally obliquely inserted anthers and an ebracteolate pedicel, we compared it to species described by Murbeck in 1933. The new species can be easily distinguished from the other Iranian species by having bi-colored hairs on the stamen filaments and the unique anther and pedicel characters. A distribution map is provided. The name of new species comes from Shahsavar, the ancient name of Tonekabon, an old coastal city on the Caspian Sea.

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