Studies on morphology of species from the genus Pyramimonas Schmarda (Prasinophyceae) new for the Far Eastern seas of Russia

2005 ◽  
Vol 7 (3) ◽  
pp. 247-255 ◽  
Author(s):  
I. V. Stonik ◽  
N. A. Aizdaicher
Keyword(s):  
2020 ◽  
Vol 46 (1) ◽  
pp. 34-41
Author(s):  
N. M. Aminina ◽  
T. I. Vishnevskaya ◽  
E. P. Karaulova ◽  
N. V. Epur ◽  
E. V. Yakush

Fisheries ◽  
2021 ◽  
Vol 2021 (6) ◽  
pp. 63-71
Author(s):  
Artur Maiss ◽  
Natalya Maiss

The article proposed to discuss a concept of new strategy for the sustainable use of populations of aquatic organisms using as an example a fishery for Walleye Pollock in the Far Eastern seas of the Russian Federation. It is shown that the current regulations governing the impact of fishing contained in the Fishing Regulations do not quite consider changes related to the dynamics of pollock populations parameters. As a result, there is an uncontrolled and often negative impact of fishing, which leads to changes in the phenotypic and size-age structure of W. Pollock populations being fished, which ultimately affects the profitability of fishing. It is proposed to develop a separate strategy for each W. Pollock stock unit, which annually regulates the level of fishing impact, depending on the state of the stocks and market conditions. The proposed strategy concept makes it possible to regulate not only the allowable volume of catch, but also the size structure of catches, by changing the fishing parameters every year. It will keep the harvested stocks stable and will help to obtain the maximum possible fishing profitability.


Author(s):  
Natalia P. Fadeeva ◽  
Vladimir V. Mordukhovich ◽  
Julia K. Zograf

Three species: Oxyonchus orientalis sp. nov., O. sakchalinensis sp. nov., and O. nicholasi sp. nov. (Thoracostomopsidae: Nematoda) are described and illustrated with the aid of light microscopy and laser-scanning microscopy pictures from sediments of Far Eastern Seas (the one former species from the Sea of Japan, Eastern Russia and the two latter species from the Sea of Okhotsk, Sakhalin Island). Generic diagnosis is emended for identification of Oxyonchus. Oxyonchus orientalis sp. nov. has short cephalic sensillae (0.6 cephalic diameters), strongly developed broad mandibular plate with irregular arrangement of numerous small denticles. Oxyonchus sakhalinensis sp. nov. is particularly characterized by the weakly short cephalic capsule, and the rounded thin mandibular plates with 10 denticles. Oxyonchus nicholasi sp. nov. can be differentiated by the structure of the cephalic armament (well developed capsule, fenestrae and incisions), numerous long cervical setae and tail shape. The distribution patterns of the various Oxyonchus species was suggested.


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