Effect of starvation on the biochemical compositions and respiration rates of ctenophores Mnemiopsis leidyi and Beroe ovata in the Black Sea

2005 ◽  
Vol 85 (3) ◽  
pp. 549-561 ◽  
Author(s):  
B.E. Anninsky ◽  
G.A. Finenko ◽  
G.I. Abolmasova ◽  
E.S. Hubareva ◽  
L.S. Svetlichny ◽  
...  
Keyword(s):  
Organic Matter ◽  
Black Sea ◽  
Biochemical Composition ◽  
Organic Matter Content ◽  
The Black Sea ◽  
Mnemiopsis Leidyi ◽  
Total Organic Matter ◽  
Total Carbohydrate ◽  
Beroe Ovata ◽  
Wet Weight

The proximate biochemical composition and metabolic rates of ctenophores Mnemiopsis leidyi and Beroe ovata from the Black Sea were examined with respect to starvation conditions. Although organic matter content in B. ovata was two times higher than that of M. leidyi (2.51 ±0.53 and 1.14 ±0.17 mg g-1 of wet weight, respectively), these species did not significantly differ in their biochemical composition. In both species protein formed about 80% of the total organic matter, lipids amounted to about 10%. Carbohydrate and amino acids measured separately made up less than 6.5% of the total organic matter. Under experimental starvation (18 days at 16—18°C for B. ovata and 8 days at 12.4°C for M. leidyi), wet weights of both ctenophore species were reduced by 9.4% and 9.3% d-1, respectively. The rate of organic matter decrease was nearly two times lower than that of wet weight being on average 5.9% d-1 in M. leidyi and 5.5% d-1 in B. ovata. There was no trend in percentage of the four major biochemical categories with starvation time. The glycogen content in polysaccharides reached maximum values in freshly collected ctenophores (76.0 ±7.9% in B. ovata, and 86.6% in M. leidyi), but it was reduced substantially (34.4 ±2.7% in B. ovata and 18.3—28.8% in M. leidyi) with starvation. Monosaccharide content, expressed as a percentage of total carbohydrate, decreased from 39.9% to 13.5% in B. ovata, and from 45.8% to 14.3—23.2% in M. leidyi. The relationship between respiration rate (R) and wet weight (W) of individuals during the starvation can be expressed by power function R = R1 Wk (r2=0.85—0.94; P>0.001) for both ctenophore species. On average, k values were 0.95 and 0.83 in B. ovata and in M. leidyi, respectively. By the end of the starvation, metabolic rate per unit wet weight decreased by 33% in B. ovata and 46% in M. leidyi. Organic matter utilization was almost totally explained by respiration of ctenophores in the experiments and exceeded metabolic requirements of studied species by 11% and 15%, correspondingly. As compared with Mnemiopsis, Beroe has better tolerance to starvation which explains to some extent the success of the species survival during prolonged periods of food shortage in the Black Sea conditions.

Effect of invasive ctenophores Mnemiopsis leidyi and Beroe ovata on low trophic webs of the Black Sea ecosystem

2019 ◽  
Vol 141 ◽  
pp. 434-447 ◽  
Author(s):  
T.A. Shiganova ◽  
A.S. Mikaelyan ◽  
S. Moncheva ◽  
K. Stefanova ◽  
V.K. Chasovnikov ◽  
...  
Keyword(s):  
Black Sea ◽  
The Black Sea ◽  
Mnemiopsis Leidyi ◽  
Beroe Ovata ◽  
Trophic Webs

scholarly journals The Abundance and Biomass Dynamic of Populations the Black Sea Macrozooplankton

2020 ◽  
Vol 6 (5) ◽  
pp. 74-82
Author(s):  
N. Louppova
Keyword(s):  
Black Sea ◽  
Aurelia Aurita ◽  
The Other ◽  
The Black Sea ◽  
Mnemiopsis Leidyi ◽  
Beroe Ovata ◽  
Successful Reproduction ◽  
Mass Reproduction ◽  
Biomass Dynamic

The abundance and biomass dynamic of massive macrozooplankton of the Black Sea was studied over 3 years. Data on the dates of mass reproduction of Jellyfish Aurelia aurita and Ctenophore invaders Mnemiopsis leidyi and Beroe ovata were obtained. The dependence of M. leidyi reproduction on the season and temperature of the medium was established, and for the other two gelatinous, on the successful reproduction of Mnemiopsis.

Modelling assessment of interactions in the Black Sea of the invasive ctenophores Mnemiopsis leidyi and Beroe ovata

2018 ◽  
Vol 376 ◽  
pp. 1-14 ◽  
Author(s):  
Shiganova Tamara A. ◽  
Elena Alekseenko ◽  
Moskalenko Lidia ◽  
Nival Paul
Keyword(s):  
Black Sea ◽  
The Black Sea ◽  
Mnemiopsis Leidyi ◽  
Beroe Ovata

scholarly journals Seasonal Variations in the Dynamics of the Number and Biomass of the Black Sea Macrozooplankton Populations

2021 ◽  
Vol 7 (12) ◽  
pp. 41-46
Author(s):  
N. Louppova
Keyword(s):  
Life Expectancy ◽  
Black Sea ◽  
Seasonal Variations ◽  
The Black Sea ◽  
Mnemiopsis Leidyi ◽  
Average Life ◽  
Average Life Expectancy ◽  
Beroe Ovata ◽  
Northeastern Shelf ◽  
Biomass Dynamics

The abundance and biomass dynamics of the jellyfish Aurelia aurita and ctenophores-invadors Mnemiopsis leidyi and Beroe ovata in 2019 on the northeastern shelf of the Black Sea were studied. Data on the maxima of reproduction of each species of gelatinous macrozooplankton were obtained, as well as conclusions on the dynamics of individuals growth in populations and average life expectancy were drawn.

Changes in appendicularian Oikopleura dioica abundance caused by invasion of alien ctenophores in the Black Sea

2005 ◽  
Vol 85 (3) ◽  
pp. 477-494 ◽  
Author(s):  
Tamara Shiganova
Keyword(s):  
Black Sea ◽  
Standing Stock ◽  
Zooplankton Community ◽  
The Black Sea ◽  
Mnemiopsis Leidyi ◽  
Total Zooplankton ◽  
Oikopleura Dioica ◽  
Beroe Ovata ◽  
Term Data

Oikopleura dioica is the only recorded appendicularian in the Black Sea. During the last two decades major changes in the O. dioica population size as well as total zooplankton community structures were recorded when invasive ctenophore species appeared in the Black Sea ecosystem. The state of the O. dioica population, before the invasion of ctenophores Mnemiopsis leidyi and Beroe ovata, is reviewed. The effect of the invasion of these ctenophores on the total zooplankton and particularly on the O. dioica standing stock is summarized from our long-term data and published information. The abundance, biomass and species composition of zooplankton greatly decreased after the ctenophore Mnemiopsis leidyi invasion due to predation by M. leidyi. Specifically, the abundance of O. dioica declined at that period. But with increasing numbers of a new invader, the ctenophore Beroe ovata, a predator of M. leidyi, in 1999, the zooplankton community began to recover. The population density of Oikopleura dioica also gradually increased to a level that was within the range of its abundance before the M. leidyi outbreak and even higher due to increasing its prey bacteria, which was provoked by the mucus released by B. ovata.

Population development of the invader ctenophore Mnemiopsis leidyi , in the Black Sea and in other seas of the Mediterranean basin

2001 ◽  
Vol 139 (3) ◽  
pp. 431-445 ◽  
Author(s):  
Shiganova T. ◽  
Mirzoyan Z. ◽  
Studenikina E. ◽  
Volovik S. ◽  
Siokou-Frangou I. ◽  
...  
Keyword(s):  
Black Sea ◽  
Mediterranean Basin ◽  
The Black Sea ◽  
Mnemiopsis Leidyi ◽  
Population Development ◽  
The Mediterranean ◽  
The Mediterranean Basin

scholarly journals Drivers, mechanisms and long-term variability of seasonal hypoxia on the Black Sea northwestern shelf – is there any recovery after eutrophication?

2013 ◽  
Vol 10 (6) ◽  
pp. 3943-3962 ◽  
Author(s):  
A. Capet ◽  
J.-M. Beckers ◽  
M. Grégoire
Keyword(s):  
Organic Matter ◽  
Spatial Distribution ◽  
Interannual Variability ◽  
Black Sea ◽  
Sea Surface ◽  
The Black Sea ◽  
Northwestern Shelf ◽  
Bottom Waters ◽  
Seasonal Hypoxia ◽  
Bottom Hypoxia

Abstract. The Black Sea northwestern shelf (NWS) is a shallow eutrophic area in which the seasonal stratification of the water column isolates the bottom waters from the atmosphere. This prevents ventilation from counterbalancing the large consumption of oxygen due to respiration in the bottom waters and in the sediments, and sets the stage for the development of seasonal hypoxia. A three-dimensional (3-D) coupled physical–biogeochemical model is used to investigate the dynamics of bottom hypoxia in the Black Sea NWS, first at seasonal and then at interannual scales (1981–2009), and to differentiate its driving factors (climatic versus eutrophication). Model skills are evaluated by a quantitative comparison of the model results to 14 123 in situ oxygen measurements available in the NOAA World Ocean and the Black Sea Commission databases, using different error metrics. This validation exercise shows that the model is able to represent the seasonal and interannual variability of the oxygen concentration and of the occurrence of hypoxia, as well as the spatial distribution of oxygen-depleted waters. During the period 1981–2009, each year exhibits seasonal bottom hypoxia at the end of summer. This phenomenon essentially covers the northern part of the NWS – which receives large inputs of nutrients from the Danube, Dniester and Dnieper rivers – and extends, during the years of severe hypoxia, towards the Romanian bay of Constanta. An index H which merges the aspects of the spatial and temporal extension of the hypoxic event is proposed to quantify, for each year, the intensity of hypoxia as an environmental stressor. In order to explain the interannual variability of H and to disentangle its drivers, we analyze the long time series of model results by means of a stepwise multiple linear regression. This statistical model gives a general relationship that links the intensity of hypoxia to eutrophication and climate-related variables. A total of 82% of the interannual variability of H is explained by the combination of four predictors: the annual riverine nitrate load (N), the sea surface temperature in the month preceding stratification (Ts), the amount of semi-labile organic matter accumulated in the sediments (C) and the sea surface temperature during late summer (Tf). Partial regression indicates that the climatic impact on hypoxia is almost as important as that of eutrophication. Accumulation of organic matter in the sediments introduces an important inertia in the recovery process after eutrophication, with a typical timescale of 9.3 yr. Seasonal fluctuations and the heterogeneous spatial distribution complicate the monitoring of bottom hypoxia, leading to contradictory conclusions when the interpretation is done from different sets of data. In particular, it appears that the recovery reported in the literature after 1995 was overestimated due to the use of observations concentrated in areas and months not typically affected by hypoxia. This stresses the urgent need for a dedicated monitoring effort in the Black Sea NWS focused on the areas and months concerned by recurrent hypoxic events.

Sign in / Sign up

Export Citation Format

Share Document