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S. Mudrak - One of the best experts on this subject based on the ideXlab platform.
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Seasonal dynamics of Pseudocalanus minutus elongatus and Acartia spp. in the southern Baltic Sea (Gda?sk Deep) ? numerical simulations
Biogeosciences, 2006Co-Authors: L. Dzierzbicka-g?owacka, L. Bielecka, S. MudrakAbstract:A population dynamics model for copepods is presented, describing the seasonal dynamics of Pseudocalanus minutus elongatus and Acartia spp. in the southern Baltic Sea (Gda?sk Deep). The copepod model was coupled with a one-dimensional physical and biological upper layer model for nutrients (total inorganic nitrogen, phosphate), phytoplankton, microzooplankton, and an early juvenile of herring as a predator. In this model, mesozooplankton (herbivorous copepods) has been introduced as an animal having definite patterns of growth in successive stages, reproduction and mortality. The populations are represented by 6 cohorts in different developmental stages, thus assuming that recruitment of the next generation occurs after a fixed period of adult life. The copepod model links trophic processes and population dynamics, and simulates individual growth within cohorts and the changes in biomass between cohorts. The simulations of annual cycles of copepods contain one complete generation of Pseudocalanus and two generations of Acartia in the whole column water, and indicate the importance of growth in the older stages of 6 cohorts of each species, to arrive at a total population biomass. The peaks of copepods' biomass are larger at the turn of June and July for Pseudocalanus and smaller in July for Acartia, lagging that of phytoplankton by ca. two mouths, due to the growth of cohorts in successive stages and egg production by females. The numerical results show that the investigated species could not be the main factor limiting the spring phytoplankton bloom in the Gda?sk Deep, because the initial development was slow for Acartia and faster for Pseudocalanus, but the main development formed after the bloom, in both cases. The phytoplankton bloom is very important in the diet of the adults of the copepods, but it is not particularly important for the youngest part of new generation (early nauplii). However, the simulated microzooplankton biomass was enough high to conclude, in our opinion, that, in this case, it was a major cause in limiting phytoplankton bloom. The model presented here is a next step in understanding how the population dynamics of a dominant species in the southern Baltic Sea interact with the environment.
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Seasonal dynamics of Pseudocalanus minutus elongatus and Acartia spp. in the southern Baltic Sea (Gda?sk Deep) ? numerical simulations
Biogeosciences Discussions, 2006Co-Authors: L. Dzierzbicka-g?owacka, L. Bielecka, S. MudrakAbstract:A population dynamics model for copepods is presented describing a seasonal dynamics of Pseudocalanus minutus elongatus and Acartia spp. in the southern Baltic Sea (Gdansk Deep). The copepod model was coupled with an one-dimensional physical and biological upper layer model for nutrients (total inorganic nitrogen, phosphate), phytoplankton, microzooplankton and an early juvenile of herring as predator. In this model, mesozooplankton (herbivorous copepods) has been introduced as animals having definite patterns of growth in successive stages, reproduction and mortality. The populations are represented by 6 cohorts in different developmental stages, thus assuming, that recruitment of the next generation occurs after a fixed period of adult life. The copepod model links trophic processes and population dynamics, and simulates individual growth within cohorts and the changes in biomass between cohorts. The simulations of annual cycles of copepods contain one complete generation of Pseudocalanus and two generations of Acartia in the whole column water, and indicate the importance of growth of older stages of 6 cohorts each species to total population biomass. The peaks of copepods biomass, main, at the turn of June and July for Pseudocalanus and smaller, in July for Acartia, lag that phytoplankton by ca. two mouths due to growth of cohorts in successive stages and egg production by females. The numerical results show that the investigated species could not be the main factor limiting the spring phytoplankton bloom in the Gdansk Deep, because the initial development was slow for Acartia and faster for Pseudocalanus, but main development formed after the bloom, in both cases. However, the simulated microzooplankton biomass was enough high to conclude, in our opinion, that, in this case, it was major cause limiting phytoplankton bloom. Model presented here is a next step in understanding how the population dynamics of a dominant species in the southern Baltic Sea interact with the environment.
L. Dzierzbicka-g?owacka - One of the best experts on this subject based on the ideXlab platform.
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Seasonal dynamics of Pseudocalanus minutus elongatus and Acartia spp. in the southern Baltic Sea (Gda?sk Deep) ? numerical simulations
Biogeosciences, 2006Co-Authors: L. Dzierzbicka-g?owacka, L. Bielecka, S. MudrakAbstract:A population dynamics model for copepods is presented, describing the seasonal dynamics of Pseudocalanus minutus elongatus and Acartia spp. in the southern Baltic Sea (Gda?sk Deep). The copepod model was coupled with a one-dimensional physical and biological upper layer model for nutrients (total inorganic nitrogen, phosphate), phytoplankton, microzooplankton, and an early juvenile of herring as a predator. In this model, mesozooplankton (herbivorous copepods) has been introduced as an animal having definite patterns of growth in successive stages, reproduction and mortality. The populations are represented by 6 cohorts in different developmental stages, thus assuming that recruitment of the next generation occurs after a fixed period of adult life. The copepod model links trophic processes and population dynamics, and simulates individual growth within cohorts and the changes in biomass between cohorts. The simulations of annual cycles of copepods contain one complete generation of Pseudocalanus and two generations of Acartia in the whole column water, and indicate the importance of growth in the older stages of 6 cohorts of each species, to arrive at a total population biomass. The peaks of copepods' biomass are larger at the turn of June and July for Pseudocalanus and smaller in July for Acartia, lagging that of phytoplankton by ca. two mouths, due to the growth of cohorts in successive stages and egg production by females. The numerical results show that the investigated species could not be the main factor limiting the spring phytoplankton bloom in the Gda?sk Deep, because the initial development was slow for Acartia and faster for Pseudocalanus, but the main development formed after the bloom, in both cases. The phytoplankton bloom is very important in the diet of the adults of the copepods, but it is not particularly important for the youngest part of new generation (early nauplii). However, the simulated microzooplankton biomass was enough high to conclude, in our opinion, that, in this case, it was a major cause in limiting phytoplankton bloom. The model presented here is a next step in understanding how the population dynamics of a dominant species in the southern Baltic Sea interact with the environment.
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Seasonal dynamics of Pseudocalanus minutus elongatus and Acartia spp. in the southern Baltic Sea (Gda?sk Deep) ? numerical simulations
Biogeosciences Discussions, 2006Co-Authors: L. Dzierzbicka-g?owacka, L. Bielecka, S. MudrakAbstract:A population dynamics model for copepods is presented describing a seasonal dynamics of Pseudocalanus minutus elongatus and Acartia spp. in the southern Baltic Sea (Gdansk Deep). The copepod model was coupled with an one-dimensional physical and biological upper layer model for nutrients (total inorganic nitrogen, phosphate), phytoplankton, microzooplankton and an early juvenile of herring as predator. In this model, mesozooplankton (herbivorous copepods) has been introduced as animals having definite patterns of growth in successive stages, reproduction and mortality. The populations are represented by 6 cohorts in different developmental stages, thus assuming, that recruitment of the next generation occurs after a fixed period of adult life. The copepod model links trophic processes and population dynamics, and simulates individual growth within cohorts and the changes in biomass between cohorts. The simulations of annual cycles of copepods contain one complete generation of Pseudocalanus and two generations of Acartia in the whole column water, and indicate the importance of growth of older stages of 6 cohorts each species to total population biomass. The peaks of copepods biomass, main, at the turn of June and July for Pseudocalanus and smaller, in July for Acartia, lag that phytoplankton by ca. two mouths due to growth of cohorts in successive stages and egg production by females. The numerical results show that the investigated species could not be the main factor limiting the spring phytoplankton bloom in the Gdansk Deep, because the initial development was slow for Acartia and faster for Pseudocalanus, but main development formed after the bloom, in both cases. However, the simulated microzooplankton biomass was enough high to conclude, in our opinion, that, in this case, it was major cause limiting phytoplankton bloom. Model presented here is a next step in understanding how the population dynamics of a dominant species in the southern Baltic Sea interact with the environment.
L. Bielecka - One of the best experts on this subject based on the ideXlab platform.
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Seasonal dynamics of Pseudocalanus minutus elongatus and Acartia spp. in the southern Baltic Sea (Gdańsk Deep) – numerical simulations
Biogeosciences, 2006Co-Authors: Lidia Dzierzbicka-głowacka, L. Bielecka, Stella MudrakAbstract:Abstract. A population dynamics model for copepods is presented, describing the seasonal dynamics of Pseudocalanus minutus elongatus and Acartia spp. in the southern Baltic Sea (Gdansk Deep). The copepod model was coupled with a one-dimensional physical and biological upper layer model for nutrients (total inorganic nitrogen, phosphate), phytoplankton, microzooplankton, and an early juvenile of herring as a predator. In this model, mesozooplankton (herbivorous copepods) has been introduced as an animal having definite patterns of growth in successive stages, reproduction and mortality. The populations are represented by 6 cohorts in different developmental stages, thus assuming that recruitment of the next generation occurs after a fixed period of adult life. The copepod model links trophic processes and population dynamics, and simulates individual growth within cohorts and the changes in biomass between cohorts. The simulations of annual cycles of copepods contain one complete generation of Pseudocalanus and two generations of Acartia in the whole column water, and indicate the importance of growth in the older stages of 6 cohorts of each species, to arrive at a total population biomass. The peaks of copepods' biomass are larger at the turn of June and July for Pseudocalanus and smaller in July for Acartia, lagging that of phytoplankton by ca. two mouths, due to the growth of cohorts in successive stages and egg production by females. The numerical results show that the investigated species could not be the main factor limiting the spring phytoplankton bloom in the Gdansk Deep, because the initial development was slow for Acartia and faster for Pseudocalanus, but the main development formed after the bloom, in both cases. The phytoplankton bloom is very important in the diet of the adults of the copepods, but it is not particularly important for the youngest part of new generation (early nauplii). However, the simulated microzooplankton biomass was enough high to conclude, in our opinion, that, in this case, it was a major cause in limiting phytoplankton bloom. The model presented here is a next step in understanding how the population dynamics of a dominant species in the southern Baltic Sea interact with the environment.
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Seasonal dynamics of Pseudocalanus minutus elongatus and Acartia spp. in the southern Baltic Sea (Gda?sk Deep) ? numerical simulations
Biogeosciences, 2006Co-Authors: L. Dzierzbicka-g?owacka, L. Bielecka, S. MudrakAbstract:A population dynamics model for copepods is presented, describing the seasonal dynamics of Pseudocalanus minutus elongatus and Acartia spp. in the southern Baltic Sea (Gda?sk Deep). The copepod model was coupled with a one-dimensional physical and biological upper layer model for nutrients (total inorganic nitrogen, phosphate), phytoplankton, microzooplankton, and an early juvenile of herring as a predator. In this model, mesozooplankton (herbivorous copepods) has been introduced as an animal having definite patterns of growth in successive stages, reproduction and mortality. The populations are represented by 6 cohorts in different developmental stages, thus assuming that recruitment of the next generation occurs after a fixed period of adult life. The copepod model links trophic processes and population dynamics, and simulates individual growth within cohorts and the changes in biomass between cohorts. The simulations of annual cycles of copepods contain one complete generation of Pseudocalanus and two generations of Acartia in the whole column water, and indicate the importance of growth in the older stages of 6 cohorts of each species, to arrive at a total population biomass. The peaks of copepods' biomass are larger at the turn of June and July for Pseudocalanus and smaller in July for Acartia, lagging that of phytoplankton by ca. two mouths, due to the growth of cohorts in successive stages and egg production by females. The numerical results show that the investigated species could not be the main factor limiting the spring phytoplankton bloom in the Gda?sk Deep, because the initial development was slow for Acartia and faster for Pseudocalanus, but the main development formed after the bloom, in both cases. The phytoplankton bloom is very important in the diet of the adults of the copepods, but it is not particularly important for the youngest part of new generation (early nauplii). However, the simulated microzooplankton biomass was enough high to conclude, in our opinion, that, in this case, it was a major cause in limiting phytoplankton bloom. The model presented here is a next step in understanding how the population dynamics of a dominant species in the southern Baltic Sea interact with the environment.
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Seasonal dynamics of Pseudocalanus minutus elongatus and Acartia spp. in the southern Baltic Sea (Gda?sk Deep) ? numerical simulations
Biogeosciences Discussions, 2006Co-Authors: L. Dzierzbicka-g?owacka, L. Bielecka, S. MudrakAbstract:A population dynamics model for copepods is presented describing a seasonal dynamics of Pseudocalanus minutus elongatus and Acartia spp. in the southern Baltic Sea (Gdansk Deep). The copepod model was coupled with an one-dimensional physical and biological upper layer model for nutrients (total inorganic nitrogen, phosphate), phytoplankton, microzooplankton and an early juvenile of herring as predator. In this model, mesozooplankton (herbivorous copepods) has been introduced as animals having definite patterns of growth in successive stages, reproduction and mortality. The populations are represented by 6 cohorts in different developmental stages, thus assuming, that recruitment of the next generation occurs after a fixed period of adult life. The copepod model links trophic processes and population dynamics, and simulates individual growth within cohorts and the changes in biomass between cohorts. The simulations of annual cycles of copepods contain one complete generation of Pseudocalanus and two generations of Acartia in the whole column water, and indicate the importance of growth of older stages of 6 cohorts each species to total population biomass. The peaks of copepods biomass, main, at the turn of June and July for Pseudocalanus and smaller, in July for Acartia, lag that phytoplankton by ca. two mouths due to growth of cohorts in successive stages and egg production by females. The numerical results show that the investigated species could not be the main factor limiting the spring phytoplankton bloom in the Gdansk Deep, because the initial development was slow for Acartia and faster for Pseudocalanus, but main development formed after the bloom, in both cases. However, the simulated microzooplankton biomass was enough high to conclude, in our opinion, that, in this case, it was major cause limiting phytoplankton bloom. Model presented here is a next step in understanding how the population dynamics of a dominant species in the southern Baltic Sea interact with the environment.
Ernestina Castro-longoria - One of the best experts on this subject based on the ideXlab platform.
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Discrimination between Acartia (Copepoda: Calanoida) species using their diffraction pattern in a position, rotation invariant digital correlation
Journal of Plankton Research, 2003Co-Authors: Josué Álvarez-borrego, Ernestina Castro-longoriaAbstract:Digital images of Acartia discaudata, A. clausi, A. margalefi and A. tonsa were processed to obtain their diffraction pattern. To discriminate between species and sex all diffraction patterns were correlated with a spatial filter, invariant to position and rotation, for each Acartia male and female. This filter was made up using a combination of different images of each species and sex. Considering the great similarity between the copepod species used in this work and between the male and female of each species the results obtained are very good. It is concluded that the method used to discriminate between species of this congeneric group can be very useful for the development of an automated system for the identification of copepods.
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EGG PRODUCTION AND HATCHING SUCCESS OF FOUR Acartia SPECIES UNDER DIFFERENT TEMPERATURE AND SALINITY REGIMES
Journal of Crustacean Biology, 2003Co-Authors: Ernestina Castro-longoriaAbstract:Abstract Egg production and hatching success of four Acartia species from the Solent-Southampton Water estuarine system were determined under different temperature (5–20°C) and salinity (15–35 psu) laboratory regimes. Fecundity typically increased with increasing temperature for all species, and hatching success was suppressed at 5°C and 10°C in all species. With respect to salinity, egg production patterns were more irregular, but some species produced fewer eggs at the lowest salinity tested. At a 24 h incubation period, some differences in hatching success were obtained at the different salinities tested. Results indicate that temperature plays an important role in the population dynamics of the congeneric group Acartia within the system and that salinity changes may also influence the fecundity of the species.
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Comparative observations on the external morphology of subitaneous and diapause eggs of Acartia species from Southampton Water
Crustaceana, 2001Co-Authors: Ernestina Castro-longoriaAbstract:[Eggs produced by four Acartia species from the Solent-Southampton Water estuarine system were examined. Acartia tonsa produced two morphologically distinct types of eggs, which were identified as subitaneous and diapause. Diapause eggs from this species were spiny while the subitaneous form had a relatively smooth chorion surface; a second subitaneous egg was produced by A. tonsa, which had significant spine extensions on the surface. Acartia margalefi, A. discaudata, and A. clausi produced only smooth eggs, which were identified as subitaneous. Observations under scanning electron microscopy (SEM) revealed consistent interspecific variations in the texture of the chorion surface of both subitaneous and diapause eggs in all species. Les oeufs produits par quatre especes d'Acartia du systeme estuarien Solent-Southampton ont ete examines. Acartia tonsa a produit deux types d'oeufs morphologiquement distincts, qui ont ete identifies comme oeufs immediats et oeufs de diapause. Les oeufs de diapause de cette espece presentaient des epines tandis que la forme immediate avait une surface chorionique relativement lisse; un second type d'oeuf immediat a ete produit par A. tonsa, qui avait, a sa surface, des extensions epineuses importantes. Acartia margalefi, A. discaudata et A. clausi n'ont produit que des oeufs lisses, qui ont ete identifies comme oeufs immediats. Des observations realisees en microscopie electronique a balayage ont releve des variations interspecifiques significatives de la texture de la surface du chorion chez les oeufs immediats comme chez les oeufs de diapause de toutes les especes., Eggs produced by four Acartia species from the Solent-Southampton Water estuarine system were examined. Acartia tonsa produced two morphologically distinct types of eggs, which were identified as subitaneous and diapause. Diapause eggs from this species were spiny while the subitaneous form had a relatively smooth chorion surface; a second subitaneous egg was produced by A. tonsa, which had significant spine extensions on the surface. Acartia margalefi, A. discaudata, and A. clausi produced only smooth eggs, which were identified as subitaneous. Observations under scanning electron microscopy (SEM) revealed consistent interspecific variations in the texture of the chorion surface of both subitaneous and diapause eggs in all species. Les oeufs produits par quatre especes d'Acartia du systeme estuarien Solent-Southampton ont ete examines. Acartia tonsa a produit deux types d'oeufs morphologiquement distincts, qui ont ete identifies comme oeufs immediats et oeufs de diapause. Les oeufs de diapause de cette espece presentaient des epines tandis que la forme immediate avait une surface chorionique relativement lisse; un second type d'oeuf immediat a ete produit par A. tonsa, qui avait, a sa surface, des extensions epineuses importantes. Acartia margalefi, A. discaudata et A. clausi n'ont produit que des oeufs lisses, qui ont ete identifies comme oeufs immediats. Des observations realisees en microscopie electronique a balayage ont releve des variations interspecifiques significatives de la texture de la surface du chorion chez les oeufs immediats comme chez les oeufs de diapause de toutes les especes.]
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Acartia BIFILOSA (COPEPODA, CALANOIDA): ACANTHAcartia OR ACARTIURA?
Crustaceana, 1999Co-Authors: Ernestina Castro-longoria, John A. WilliamsAbstract:Adult specimens of Acartia bifilosa have been examined under SEM and evidence of the presence of rostral filaments in this species is confirmed. The suggestion of Shim & Choi (1996) to change its taxonomic position from the subgenus AcanthAcartia to the subgenus Acartiura is therefore rejected. This report clearly shows that A. bifilosa should remain in its current taxonomic position, although further taxonomic/genetic studies on this species are necessary. Des specimens adultes d' Acartia bifilosa ont ete examines sous MEB et la presence de filaments rostraux chez cette espece est confirmee. La suggestion de Shim & Choi (1996) de deplacer sa position taxonomique du sous-genre AcanthAcartia au sous-genre Acartiura est de ce fait rejetee. Ces observations montrent clairement qu' A. bifilosa devrait conserver sa position taxonomique courante, bien que des etudes taxonomiques/genetiques complementaires sur cette espece soient necessaires.
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First report of the presence of Acartia margalefi (Copepoda: Calanoida) in Southampton Water and Horsea Lake, UK
Journal of Plankton Research, 1996Co-Authors: Ernestina Castro-longoria, John A. WilliamsAbstract:Acartia margalefi is recorded for the first time in British waters, where it is found to be an important copepod in the mesozooplankton community structure of Southampton Water and Horsea Lake. Within the genus Acartia, this species occurs all through the annual cycle. Abundance is higher in the upper estuary, where the range of temperature and salinity is relatively wider over the year. It is clear that A.margalefi is an estuarine species which can tolerate a significant range of temperature.
Tatsuki Toda - One of the best experts on this subject based on the ideXlab platform.
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Spiny but Subitaneous Eggs: Egg Morphology and Hatching in Acartia Copepods in the Tropics.
Zoological studies, 2019Co-Authors: Ryota Nakajima, Teruaki Yoshida, B. H. R. Othman, Sakiko Orui Sakaguchi, Tatsuki TodaAbstract:Egg surface ornamentation, egg production rates, and hatching success of two calanoid copepod species (Acartia pacifica and Acartia cf. erythraea) were examined in a tropical coral reef of Tioman Island, Malaysia, near the equator (2°N). All observed females of A. pacifica and A. cf. erythraea produced eggs with spines on the surface, either short or long, which are common in resting eggs in temperate ecosystems that hatch when environmental conditions are favorable or after a certain refractory period. However, all of these spiny eggs in the present study hatched within 48 hours when exposed to ambient seawater temperature, suggesting that they were subitaneous eggs. Such spine ornamentation has been thought to be an adaptive feature only for resting eggs to survive during egg dormancy, but the presence of spines on subitaneous eggs suggests further possible functions of these spines such as reducing the risks of ingestion by predators.
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Seasonal changes in abundance of four Acartia species (Copepoda, Calanoida) in the coastal waters of Peninsular Malaysia; relationship with monsoon transition
Regional Studies in Marine Science, 2018Co-Authors: Mohd Zuraire, Tatsuki Toda, Zaidi Che Cob, B. H. R. Othman, Teruaki YoshidaAbstract:Abstract The seasonal variation of Acartia copepods from the waters of Peninsular Malaysia was studied via monthly observations at 2 fixed stations on the west coast (Pulau Pinang and Port Dickson) and 2 fixed stations on the east coast (Kijal and Penyabong) from October 2012 to March 2014. In situ temperatures recorded during this period were relatively constant (mean 29.6 ± 0 . 7 ° C) at all stations. Salinity measurements were also fairly constant (mean 30.3 ± 1.1 PSU) for all stations during this study except at Penyabong where the salinity during the northeast (NE) monsoon season was significantly lower (p ± 5 . 4 μ g/L) than during the NE monsoon period. Four species of Acartia were identified at all stations: A. amboinensis, A. erythraea, A. pacifica and A. spinicauda. At Kijal, Acartia erythraea population was significantly higher (p
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Food Size Dependent Feeding and Egg Production of Acartia pacifica from a Tropical Strait
Bulletin of Marine Science, 2012Co-Authors: Teruaki Yoshida, Er Jin Eio, Tatsuki Toda, Bin Haji Ross OthmanAbstract:A study was carried out to observe the effect of food size spectra and food concentration on the ingestion rate and egg production rate (EPR) of Acartia pacifica (Steuer, 1915), a small calanoid copepod (total length 1.0-1.3 mm), from the Strait of Malacca. Food particles were divided into four size fractions (10-20, 20-35, 35-50, and 50-140 ?m) and quantified in terms of chlorophyll a concentration and carbon biomass with the C:N values used as an indication of food quality. Acartia pacifica showed significantly higher carbon ingestion rates for the 50-140 ?m food size fraction, reflecting the species' affinity for larger food particles; however, mean EPR was significantly higher for the 35-50 ?m food size fraction where the mean C:N value was 14.7. Similarly, gross egg production efficiency (Ep) was the highest for this food size fraction. In general, Ep was comparable to other Acartia species from tropical areas, but lower than those from temperate regions. This probably is due to a higher metabolic carbon demand and a lower quality of food in the tropical environment. Acartia pacifica effectively utilized food from the broad size spectrum used in our study with an affinity for larger particles with higher (though not highest) C:N content.
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Description of Naupliar Stages in Acartia steueri Smirnov (Copepoda: Calanoida)
Journal of Crustacean Biology, 2009Co-Authors: Nobutaka Okada, Bin Haji Ross Othman, Yasuko Onoue, Tomohiko Kikuchi, Tatsuki TodaAbstract:Abstract The six naupliar stages of Acartia (AcanthAcartia) steueri Smirnov, a calanoid copepod of the family Acartiidae, are described by both light microscopy and scanning electron microscopy. Each stage is discriminated by the number of setae on the distal segment of the antennule. The nauplii of A. steueri can be distinguished from those of two con-subgeneric species, Acartia (A.) californiensis Trinast and A. (A.) bifilosa Giesbrecht, by both the combination and the constancy in all naupliar stages of the exopodal setal counts of the antenna and mandible.
