Diel Variations in the Vertical Distribution of Crustacean Zooplankton and Food Selection by Planktivorous Fish in a Shallow Turbid Lake

2004 ◽  
Vol 89 (3) ◽  
pp. 238-249 ◽  
Author(s):  
Erika Alajärvi ◽  
Jukka Horppila
Keyword(s):  
Vertical Distribution ◽  
Food Selection ◽  
Planktivorous Fish ◽  
Crustacean Zooplankton ◽  
Diel Variations ◽  
Turbid Lake ◽  
The Vertical Distribution ◽  
Shallow Turbid Lake

scholarly journals Study of vertical distribution of zooplankton in Zaporozhskoye Reservoir aiming to calculate bighead carp stocking

2018 ◽  
Vol 3 (3) ◽  
pp. 57-69
Author(s):  
V. A. Yakovenko ◽  
E. Yu. Zaychenko
Keyword(s):  
Surface Layer ◽  
Vertical Distribution ◽  
Vertical Section ◽  
Stocking Density ◽  
Planktivorous Fish ◽  
Bighead Carp ◽  
Economic Losses ◽  
Forage Base ◽  
The Vertical Distribution ◽  
Zooplankton Production

The article focuses on the vertical distribution of zooplankton because of its importance for calculation of bighead carp stocking the Zaporozhskoye Reservoir. The reservoir is a water-body of complex use with fish catching being one of the priorities of the reservoir. Zooplankton is an important component of fish forage base, so accurate quantitation of zooplankton development is necessary for improving efficiency of forage base use of the reservoir by means of appropriate stocking with fish. These indicators depend significantly on the depth of the reservoir and can vary through the vertical section. At the same time, almost all investigations of the reservoir were aimed at studying the indicators of zooplankton development in the surface layer which can led to inaccurate calculations concerning the stocking of the reservoir with planktivorous fish. Therefore, the purpose of this work was not only to study the vertical distribution of zooplankton of the Zaporozhskoye Reservoir, but also to calculate the zooplankton production and the corresponding rates of stocking the reservoir with bighead carp. In summer and autumn periods, the heterogeneous vertical distribution of zooplankton was found in both parts of the reservoir. In the upper part of the reservoir, the maximum values of zooplankton development were observed in the surface and near-bottom layers whereas in the lower part of the reservoir – in the surface layer and at the depth of 10 m. Since conditions of the upper part of the reservoir are unfavorable for bighead carp, and the estimated value of the stocking density (0.3 spec.·ha-1) is negligible, no stocking of this part of the reservoir with the indicated planktivorous fish is expected. When calculating the stocking based on the zooplankton production in the surface layer only, but not in the whole water column, almost double overvaluation obtained (excess would be 246.8 thousand specimens) would lead to economic losses because of the wasteful expenditure of stocked material due to a lack of food resources. For effective utilization of zooplankton as the food base it is advisable to stock the lower part of the reservoir with two-year-old bighead carps with the stocking density of 19.1 spec.·ha-1.

scholarly journals Aspects on the seasonal dynamics and the vertical distribution of the crustacean zooplankton community and the Dreissena polymorpha larvae in Lake Trichonis

2004 ◽  
Vol 5 (1) ◽  
pp. 19 ◽  
Author(s):  
G. KEHAYIAS ◽  
E. MICHALOUDI ◽  
A. BEXI
Keyword(s):  
Vertical Distribution ◽  
Seasonal Dynamics ◽  
Dreissena Polymorpha ◽  
Zooplankton Community ◽  
Vertical Axis ◽  
Crustacean Zooplankton ◽  
Eutrophic Lakes ◽  
Main Factors ◽  
Daphnia Cucullata ◽  
The Vertical Distribution

In Lake Trichonis 9 crustacea species and the molluscan larvae of Dreissena polymorpha were recorded during four seasonal samplings from summer 2002 to spring 2003. Mean integrated values of crustacea abundance ranged from 4.5 to 12.9 ind/L and were mainly dominated by the calanoida Eudiaptomus drieschi. The abundance values recorded, as well as the seasonal dynamics, followed the monoacmic pattern of oligotrophic lakes. However, the presence of Daphnia cucullata, a typical representative of eutrophic lakes, the decrease of the calanoida participation in the crustacea community and the succession in the cladocera community, could probably indicate a tendency towards a change of the trophic condition of Lake Trichonis.Along the vertical axis the maximum abundance of the zooplankton community was recorded in the surface 0-10 m. Mollusca larvae were present in all seasons and their highest abundance was recorded in the surface layer 0-10 m. Temperature, competition and predation seemed to be the main factors regulating vertical distribution.

The vertical distribution of thin features over the Arctic analysed from CALIPSO observations. Part I: Optically thin clouds

Tellus B ◽  
2011 ◽  
Vol 63 (1) ◽  
Author(s):  
Abhay Devasthale ◽  
Michael Tjernström ◽  
Karl-Göran Karlsson ◽  
Manu Anna Thomas ◽  
Colin Jones ◽  
...  
Keyword(s):  
Vertical Distribution ◽  
The Arctic ◽  
The Vertical Distribution
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