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Louis Bernatchez - One of the best experts on this subject based on the ideXlab platform.

  • Population genomics of the southern Caspian Sea Vobla Rutilus lacustris
    Hydrobiologia, 2020
    Co-Authors: Iraj Hashemzadeh Segherloo, Fariborz Ghojoghi, Seyedeh Narjes Tabatabaei, Eric Normandeau, Cecilia Hernandez, Eric Hallerman, Brian Boyle, Louis Bernatchez
    Abstract:

    The genus Rutilus is widespread in the western and central Palearctic region. In the Caspian Sea, the taxonomic status of different populations of Rutilus lacustris  has been debated due to different sub-specific names attributed to each population. We genotyped 7,984 single nucleotide polymorphisms and sequenced the mitochondrial cytochrome C oxidase subunit I gene of 37 R. lacustris and Rutilus frisii from the southeast and southwest Caspian Sea and the Aras River in the Kura River drainage. We analysed data using clustering, Bayes factor delimitation, introgression, assessment of migration rate, and phylogenetic analyses. The results showed that the southeast and southwest Caspian Sea populations of R. lacustris were closely related, but highly differentiated from R. lacustris in the Aras River. The Bayes factor delimitation test supported the existence of three populations of R. lacustris in the studied area. Three hybrid individuals with mtDNA from Abramis brama or R. frisii and nuclear DNA from R. lacustris were detected. To protect R. lacustris in the southern Caspian Sea, we propose that the Aras River and Sea-run R. lacustris be treated as two separate conservation units and the southern Caspian Sea R. lacustris populations should be viewed as two potentially separate management units.

Imma Tolosa - One of the best experts on this subject based on the ideXlab platform.

  • aliphatic and aromatic hydrocarbons in coastal Caspian Sea sediments
    Marine Pollution Bulletin, 2004
    Co-Authors: Imma Tolosa, Stephen De Mora, Mohammad Reza Sheikholeslami, Jeanpierre Villeneuve, J Bartocci, Chantal Cattini
    Abstract:

    This investigation represents the first extensive study of the spatial distribution and sources of aliphatic (n-alkanes and unresolved complex mixture of fossil hydrocarbons) and polycyclic aromatic hydrocarbons (PAHs) in coastal sediments from the Caspian Sea. PAH concentrations, n-alkanes and biomarker profiles all suggested that there was limited petrogenic contamination in the shallow North Caspian Sea sediments, which are coarse with a low total organic carbon content. In contrast, moderate to high petrogenic contamination was found in the South Caspian Sea, in particular in the offshore oil fields near Baku, Azerbaijan. Contaminant patterns indicated that the PAHs were mainly from fossil sources, with higher contributions of pyrolytic only near industrialized and urban areas. A high contribution of perylene, a geochemically derived PAH, to the total PAHs was found in the west and south at sites influenced by the Kura, Safid Rud, Terek, Sulak and Samur Rivers.

  • organochlorinated compounds in Caspian Sea sediments
    Marine Pollution Bulletin, 2004
    Co-Authors: Stephen De Mora, Mohammad Reza Sheikholeslami, Jeanpierre Villeneuve, Chantal Cattini, Imma Tolosa
    Abstract:

    Several organochlorinated contaminants, including numerous pesticides, were determined in coastal sediments from the Caspian Sea. The most important contaminants were p; p 0 -DDT (up to 7400 pg g � 1 ) and its breakdown products, p; p 0 -DDD (up to 3400 pg g � 1 ) and p; p 0 -DDE (up to 1300 pg g � 1 ). Although the contamination was most severe in Azerbaijan, the sediment concentrations and percentage distribution of the three DDT-related compounds indicated that such contamination constitutes a contemporary and ubiquitous problem in the Caspian Sea. Lindane represented the second most significant contaminant, particularly in the Russian Federation, with concentrations up to 609 pg g � 1 . The concentrations of HCB and other chlorinated pesticides (cis- and trans-chlordane, methoxychlor, heptachlor, heptachlor epoxide, aldrin, endrin, and endosulfans) were lower and not generally of concern, but the pesticides did demonstrate markedly different distributions reflecting differing agricultural usage in the region. The concentrations of R PCBs were also quite low and ranged from 0.03 to 6.4 ng g � 1 , with the highest amounts in the Russian Fed

Anatolii D. Vlasenko - One of the best experts on this subject based on the ideXlab platform.

  • Present status of commercial stocks of sturgeons in the Caspian Sea basin
    Sturgeon Biodiversity and Conservation, 1
    Co-Authors: Raissa P. Khodorevskaya, Galina F. Dovgopol, Olga L. Zhuravleva, Anatolii D. Vlasenko
    Abstract:

    Catches for the last 25 years are analyzed for beluga Huso huso, stellate sturgeon A. stellatus and Russian sturgeon Acipenser gueldenstaedtii, which are the three commercially important species of sturgeons found in the Caspian Sea Basin. Population sizes for generations born between 1961 and 1970 are estimated, and found to depend on natural reproduction and the number of young fish stocked annually from sturgeon hatcheries located in the Volga River Delta. A ban on Sea fishing from 1962 to 1991 positively impacted the number and total biomass of commercial stocks. Sturgeon growth rates depend on water levels in the Caspian Sea. In order to preserve Caspian Sea sturgeon populations, it will be necessary to coordinate efforts of all countries surrounding the Caspian Sea to achieve rational harvests, preserve juveniles, and produce at least 100 million juveniles annually from hatcheries.

Stephen De Mora - One of the best experts on this subject based on the ideXlab platform.

  • aliphatic and aromatic hydrocarbons in coastal Caspian Sea sediments
    Marine Pollution Bulletin, 2004
    Co-Authors: Imma Tolosa, Stephen De Mora, Mohammad Reza Sheikholeslami, Jeanpierre Villeneuve, J Bartocci, Chantal Cattini
    Abstract:

    This investigation represents the first extensive study of the spatial distribution and sources of aliphatic (n-alkanes and unresolved complex mixture of fossil hydrocarbons) and polycyclic aromatic hydrocarbons (PAHs) in coastal sediments from the Caspian Sea. PAH concentrations, n-alkanes and biomarker profiles all suggested that there was limited petrogenic contamination in the shallow North Caspian Sea sediments, which are coarse with a low total organic carbon content. In contrast, moderate to high petrogenic contamination was found in the South Caspian Sea, in particular in the offshore oil fields near Baku, Azerbaijan. Contaminant patterns indicated that the PAHs were mainly from fossil sources, with higher contributions of pyrolytic only near industrialized and urban areas. A high contribution of perylene, a geochemically derived PAH, to the total PAHs was found in the west and south at sites influenced by the Kura, Safid Rud, Terek, Sulak and Samur Rivers.

  • The Caspian Sea: a microcosm for environmental science and international cooperation
    Marine Pollution Bulletin, 2004
    Co-Authors: Stephen De Mora, Tim Turner
    Abstract:

    The break up of the Soviet Union transformed the Caspian Sea from a quiet backwater into a Sea of troubles. The largest continental water body in the world now has five riparian states, with commensurate increased competition for resource utilisation. However, the Caspian lacks a legal definition. Is it a lake or a Sea? The answer influences how the boundaries are drawn between countries, thereby delineating access to resources. While the riparian states may compete for the resources, they share the environmental and biological problems because pollutants discharged into the Caspian Sea remain trapped within the basin of this land-locked system. Acknowledging a spectrum of environmental concerns and recognizing the Caspian Sea as a unique environment, the riparian states have come together to cooperate regionally to understand and prioritise the problems. Such initiatives were bolstered by widespread support from international agencies. The oil industry has also recognised its responsibility to play an active role (Efendiyeva, 2000). As a result, increased global attention in the past decade has exposed and publicised a number of grave environmental and ecological issues. Solutions rely on creating a legal framework to ensure a regional approach to environmental management and sustainable development. The main environmental problems and the recent history of international cooperation in the Caspian Sea are outlined here, and three papers in this volume document some of the issues. The Caspian Sea underwent a period of falling water level through much of the Soviet era, which encouraged human encroachment onto newly exposed shores. The water level began to rise in 1978, a trend that has resulted in an increase of 2.5 m. As a closed basin, the only surface outlet of water from the Caspian Sea is evaporation. Hydrological models based solely on evapora-

  • organochlorinated compounds in Caspian Sea sediments
    Marine Pollution Bulletin, 2004
    Co-Authors: Stephen De Mora, Mohammad Reza Sheikholeslami, Jeanpierre Villeneuve, Chantal Cattini, Imma Tolosa
    Abstract:

    Several organochlorinated contaminants, including numerous pesticides, were determined in coastal sediments from the Caspian Sea. The most important contaminants were p; p 0 -DDT (up to 7400 pg g � 1 ) and its breakdown products, p; p 0 -DDD (up to 3400 pg g � 1 ) and p; p 0 -DDE (up to 1300 pg g � 1 ). Although the contamination was most severe in Azerbaijan, the sediment concentrations and percentage distribution of the three DDT-related compounds indicated that such contamination constitutes a contemporary and ubiquitous problem in the Caspian Sea. Lindane represented the second most significant contaminant, particularly in the Russian Federation, with concentrations up to 609 pg g � 1 . The concentrations of HCB and other chlorinated pesticides (cis- and trans-chlordane, methoxychlor, heptachlor, heptachlor epoxide, aldrin, endrin, and endosulfans) were lower and not generally of concern, but the pesticides did demonstrate markedly different distributions reflecting differing agricultural usage in the region. The concentrations of R PCBs were also quite low and ranged from 0.03 to 6.4 ng g � 1 , with the highest amounts in the Russian Fed

Chantal Cattini - One of the best experts on this subject based on the ideXlab platform.

  • aliphatic and aromatic hydrocarbons in coastal Caspian Sea sediments
    Marine Pollution Bulletin, 2004
    Co-Authors: Imma Tolosa, Stephen De Mora, Mohammad Reza Sheikholeslami, Jeanpierre Villeneuve, J Bartocci, Chantal Cattini
    Abstract:

    This investigation represents the first extensive study of the spatial distribution and sources of aliphatic (n-alkanes and unresolved complex mixture of fossil hydrocarbons) and polycyclic aromatic hydrocarbons (PAHs) in coastal sediments from the Caspian Sea. PAH concentrations, n-alkanes and biomarker profiles all suggested that there was limited petrogenic contamination in the shallow North Caspian Sea sediments, which are coarse with a low total organic carbon content. In contrast, moderate to high petrogenic contamination was found in the South Caspian Sea, in particular in the offshore oil fields near Baku, Azerbaijan. Contaminant patterns indicated that the PAHs were mainly from fossil sources, with higher contributions of pyrolytic only near industrialized and urban areas. A high contribution of perylene, a geochemically derived PAH, to the total PAHs was found in the west and south at sites influenced by the Kura, Safid Rud, Terek, Sulak and Samur Rivers.

  • organochlorinated compounds in Caspian Sea sediments
    Marine Pollution Bulletin, 2004
    Co-Authors: Stephen De Mora, Mohammad Reza Sheikholeslami, Jeanpierre Villeneuve, Chantal Cattini, Imma Tolosa
    Abstract:

    Several organochlorinated contaminants, including numerous pesticides, were determined in coastal sediments from the Caspian Sea. The most important contaminants were p; p 0 -DDT (up to 7400 pg g � 1 ) and its breakdown products, p; p 0 -DDD (up to 3400 pg g � 1 ) and p; p 0 -DDE (up to 1300 pg g � 1 ). Although the contamination was most severe in Azerbaijan, the sediment concentrations and percentage distribution of the three DDT-related compounds indicated that such contamination constitutes a contemporary and ubiquitous problem in the Caspian Sea. Lindane represented the second most significant contaminant, particularly in the Russian Federation, with concentrations up to 609 pg g � 1 . The concentrations of HCB and other chlorinated pesticides (cis- and trans-chlordane, methoxychlor, heptachlor, heptachlor epoxide, aldrin, endrin, and endosulfans) were lower and not generally of concern, but the pesticides did demonstrate markedly different distributions reflecting differing agricultural usage in the region. The concentrations of R PCBs were also quite low and ranged from 0.03 to 6.4 ng g � 1 , with the highest amounts in the Russian Fed