ESTIMATION OF BREAM ABRAMIS BRAMA (LINNAEUS, 1758) POPULATION SIZE IN THE VOLGA-CASPIAN AND NORTH CASPIAN FISHERY SUBAREAS IN THE CURRENT PERIOD
Journal Title: Вестник Астраханского государственного технического университета. Серия: Рыбное хозяйство - Year 2013, Vol 0, Issue 2
Abstract
The estimation of the absolute number of bream in the Volga-Caspian and North Caspian fish-ery subareas is given. The modern mathematical method of cohort analysis and the direct method used during the researches give a complete picture of the bream population and allow etermining its reserves and the total allowable catch for the future under different environmental conditions and rational use of spawning stock. The reasons of changing the current dynamics of bream population such as changing abiotic and biotic environmental factors in the Northern Caspian Sea and the Volga river delta (reduction of the Volga runoff, level mode, increase in salinity and decrease of the biomass of food organisms) are shown. It is established that in conditions of extremely low and short flood of the Volga river the reproduction of bream was unsatisfactory during six consecutive years. All these factors negatively influenced the number of the whole generation and reduced the commercial stocks of bream from 72.0 thousands in 2002 to 48.0 thousands in 2012.
Authors and Affiliations
Levashina Vadimovna
Keywords
Related Articles
- EP ID EP151976
- DOI -
- Views 66
- Downloads 0
ACCUMULATION OF SELENIUM IN AQUATIC ORGANISMS OF THE CASPIAN SEA
The establishing of the levels of selenium accumulation in sea fish is rather actual because of surprisingly high concentrations of trace elements in fish muscles as compared with terrestrial animals and the wide spread...
LONG-TERM DYNAMICS OF HYDROBIONTS IN LAKE BALKHASH AND ITS CONNECTION WITH THE ENVIRONMENTAL FACTORS
Long-term dynamics of water level and mineralization of Lake Balkhash reflects the variability of a number of climatic factors – the total volume of ice and river runoff, the area of mountain glaciers, the amount of prec...
ФАКТОРЫ ПАТОГЕННОСТИ УСЛОВНО-ПАТОГЕННЫХ ЭНТЕРОБАКТЕРИЙ В ГИДРОЭКОСИСТЕМЕ ДЕЛЬТЫ РЕКИ ВОЛГИ
Представлены результаты исследования факторов патогенности энтеробактерий, выделенных из судака и воды в местах его обитания. Они были доминирующими в микробном пейзаже данных биотопов. Анализ показал, что все изолирован...
ИЗМЕНЧИВОСТЬ ОСТЕОЛОГИЧЕСКИХ ХАРАКТЕРИСТИК АНЧОУСОВИДНОЙ КИЛЬКИ
За последние 50 лет общее среднее количество позвонков анчоусовидной кильки уменьшилось, что связано с изменением термического режима Каспия. В результате кластерного анализа 16 выборок анчоусовидной кильки по промерам...
INFLUENCE OF THE TEMPERATURE AND pH ON THE LEVEL OF THE ACTIVITY OF THE DIGESTIVE ENZYMES OF RUSSIAN STURGEON (ACIPENSER GULDENSTADTII B.)
The adaptations of the enzymes of intestinal mucous tunic of Russian sturgeon to environmental factors (temperature and pH) are studied. It is shown that the temperature optimum for the alkaline phosphatase is located in...