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1

Biologiczny model gornej warstwy morza PhyZooNuDe fitoplankton-zooplankton-biogeny-detrytus

100%
Dzierzbicka-Glowacka L.
Działalność Naukowa PAN. Wybrane Zagadnienia
|
2001
|
tom 11
158-160
2

A two-dimensional mathematical model describing the phytoplankton distribution function in a stratified sea

100%
Dzierzbicka-Glowacka L.
Ekologia Polska
|
1992
|
tom 40
|
nr 4
479-496
3

Mathematical modelling of the chlorophyll a concentration in a stratified medium

100%
Dzierzbicka-Glowacka L.
Oceanologia
|
1996
|
tom 38
|
nr 2
4

Effects of phytoplankton mortality caused by unpredictable conditions - numerical simulations

100%
Dzierzbicka-Glowacka L.
Polish Journal of Ecology
|
2007
|
tom 55
|
nr 1
The influence of episode of density-independent mortality on the time-space variability of phytoplankton distribution in the near surface layer of a stratified sea is the aim of this paper. The mortality of phytoplankton in unpredictable conditions, like a spill of crude oil or other chemicals is considered. The numerical simulations were carried out using a biological model of upper layer with a developed primary production and regeneration mechanisms and of daily migration of zooplankton. In such cases an increase in the mortality rate intensifies the decrease in phytoplankton biomass. Such a situation can on occasion lead to phytoplankton extinction, and hence to irreversible changes in its distribution area.
5

Effect of turbulent mixing on the marine plankton vertical distribution: model simulations

100%
Dzierzbicka-Glowacka L.
Polish Journal of Ecology
|
2006
|
tom 54
|
nr 2
The effect of the turbulent mixing processes within fine structure of hydrophysical field on the prey and predator biomass is presented. The calculations were made on the basis of an one-dimensional prey-predator ecosystem model on the assumption of an absolutely stable vertical distribution of the average sea water density and that vertically intermittent layer are horizontally homogeneous. This model was tested with data obtained from the southern Gdansk Gulf (Baltic Sea). The vertical distributions of temperature and salinity fields were taken as initial conditions for various simulations. The numerical simulations were computed for different values of the wind speed. This study reveals that an intensity of the layer-mixing increase with the increase of the wind speed and duration of the turbulent disturbance. For low values of wind speed (U₁₀ < 2 m s⁻¹) and for short time of action of hydrodynamic sources of mixing (tₜ < 60 min.), fine-scale interlayering is not created in investigated case. It is also shown that the thicker the layer, the smaller the structural anomaly. The presented results demonstrate that the dynamic processes are responsible for the shape of vertical profiles of investigated characteristics to the same extent as physiological processes. Hydrodynamic conditions play a basic role where the microstructure of investigated functions is concerned.
6

A numerical investigation of nutrient concentrations in Gdansk Gulf as revealed by a coupled one-dimensional model

100%
Dzierzbicka-Glowacka L.
Polish Journal of Environmental Studies
|
2006
|
tom 15
|
nr 1
A dynamics model for nutrients was coupled with a one-dimensional physical and biological upper layer model to simulate the temporal changes not only in distributions of a nutrient but then of phytoplankton and zooplankton and study the role of these biological characteristics in the dynamics of the Gdańsk Gulf ecosystem. The 1D model consists of three submodels: a meteorological submodel for the physics of the upper layer and a biological submodel, which also is driven by output from the physical submodel. The biological upper layer model {nutrient-phytoplankton-zooplankton-detritus} incorporates formulations of the primary production mechanism and of the remineralization mechanisms within the mixed layer, in the lower layers and at the bottom as well as of the daily migration of zooplankton mechanism. The model is based on total inorganic nitrogen (NO3+NO2+NH4) and phosphate (PO4). The calculations were made for 180 days (from March to August) for two stations at Gdańsk Gulf (at station A, near the Vistula river mouth, and at station B, located further to the open sea). The results of the numerical investigations described here were compared with the mean observed values of characteristics investigated for 10 years, 1990-2000. Comparison of computed and measured values shows the model reproduces the time-vertical structure of characteristics investigated in accordance with the in situ observations. The numerical simulations shown that the differences between the simulated and mean observed values of nutrient in the upper layer are c. 1 mmol m⁻³ for total inorganic nitrogen and 0.1 mmol m-3 for phosphate. The slight differences between the calculated and observed values of surface chlorophyll-a and microzooplankton biomass are ca. 5-20%, depending on the location of the hydrographic station and the month for which the calculations were made. The model can be used to describe the temporal patterns for nutrients distributions and phytoplankton and zooplankton biomass.
7
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Modelling the seasonal dynamics of marine plankton in the Southern Baltic Sea. Part 2. Numerical simulations

100%
Dzierzbicka-Glowacka L.
Oceanologia
|
2006
|
tom 48
|
nr 1
This work presents numerical simulations of the time-dependent vertical distributions of phytoplankton, microzooplankton, Pseudocalanus elongatus, early juvenile herring (Clupea harengus) and two nutrient components (total inorganic nitrogen and phosphate) using the 1D-Coupled EcosystemMo del with a highresolution mesozooplankton (herbivorous copepods) module for P.elongatus and a simple prey-predator model for early juvenile herring C. harengus. This m odel was discussed in detail in Part 1. The calculations were done for one year (1999) for a station in the Gdańsk Deep (southern Baltic Sea). The results of the simulations were compared with the mean concentrations of nutrients, phytoplankton and zooplankton recorded in situ. The differences between the calculated and mean recorded values of nutrients and phytoplankton are c. 5–30% and depend on the month and depth for which the calculations were done. However, the calculated depth-integrated biomass of P. elongatus differs fromthe mean recorded value. This difference ranges from30 to 50% at the end of May. The 1DCEM model can be used to forecast ecological changes in the southern Baltic Sea.
8

Numerical simulations of marine zooplankton dynamics and its interaction with other system components

100%
Dzierzbicka-Glowacka L.
Polish Journal of Ecology
|
2001
|
tom 49
|
nr 1
9

Equivalence of rates of growth and egg production of Pseudocalanus

100%
Dzierzbicka-Glowacka L.
Oceanological and Hydrobiological Studies
|
2005
|
tom 34
|
nr 4
10
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Content available

Modelling the seasonal dynamics of marine plankton in the Southern Baltic Sea. Part 1. A Coupled Ecosystem Model

100%
Dzierzbicka-Glowacka L.
Oceanologia
|
2005
|
tom 47
|
nr 4
The paper presents a one-dimensional Coupled Ecosystem Model (1DCEM) consisting of three submodels: a meteorological submodel for the physics of the upper layer and a biological submodel, which is also driven by output from the physical submodel. The biological submodel with a high-resolution zooplankton module and a simple prey-predator module consists of seven mass conservation equations. There are six partial second-order differential equations of the diffusion type for phytoplankton, microzooplankton, mesozooplankton, fish, and two nutrient components (total inorganic nitrogen and phosphate). The seventh equation, an ordinary differential equation, describes the development of detritus at the bottom. In this model the mesozooplankton (herbivorous copepods) is represented by only one species – Pseudocalanus elongatus – and is composed of 6 cohorts. The fish predator is represented by 3 cohorts of early juvenile herring Clupea harengus. Hence, the biological submodel consists of an additional twelve equations, six for weights and six for the numbers in 6 cohorts of P. elongatus, and three equations for the biomasses of 3 predator cohorts. This model is an effective tool for solving the problem of ecosystem bioproductivity and was tested in Part 2 for one partcular year.
11
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Numerical studies of the influence of food ingestion on phytoplankton and zooplankton biomasses

100%
Dzierzbicka-Glowacka L.
Oceanologia
|
2002
|
tom 44
|
nr 1
This paper presents the numerical simulations of the influence of food ingestion by a herbivorous copepod on phytoplankton and zooplankton biomasses (PZB) in the sea. The numerical studies were carried out using the phytoplankton- -zooplankton-nutrient-detritus PhyZooNuDe biological upperla yer model. This takes account both of fully developed primary production and regeneration mechanisms and of daily migration of zooplankton. In this model the zooplankton is treated not as a ‘biomass’ but as organisms having definite patterns of growth, reproduction and mortality.
12
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The dependence of body weight in copepodite stages of Pseudocalanus spp. on variations of ambient temperature and food concentration

100%
Dzierzbicka-Glowacka L.
Oceanologia
|
2004
|
tom 46
|
nr 1
Quantitative expressions are presented describing the effects of temperature and food concentration on the mean body weight of copepodite stages of Pseudocalanus spp. The calculations were made on the basis of experimental data from the literature for three geographically separate populations of Pseudocalanus from Puget Sound (Washington, USA), from the southern North Sea and the Baltic Sea. Relationships were obtained between the coefficient of daily exponential growth of body weight of Pseudocalanus sp. from Puget Sound and temperature in the 8–15.5◦C range and food concentrations from 10 mgC m−3 to excess, as well as for Pseudocalanus elongatus from the southern North Sea at high food concentrations and in the 4–15◦C temperature range. Also computed was the mean body weight for stages CII to CV of P. elongatus from the southern Baltic Sea at 5◦C. The empirical models presented here can be used with good precision in mathematical models of pelagic communities. The results presented here indicate that Pseudocalanus sp. from Puget Sound (a species resembling Pseudocalanus minutus) is similar to P. elongatus from the southern North Sea and the English Channel with respect to growth parameters in the studied range of temperatures for excess food. P. elongatus collected in the Baltic Sea (Gulf of Gdańsk) differs from P. elongatus from the southern North Sea.
13

Numerical analysis of the influence of grazing on the two-dimensional distribution function of the phytoplankton concentration in a stratified sea

100%
Dzierzbicka-Glowacka L.
Oceanologia
|
1994
|
tom 36
|
nr 2
14

Encounter rates in zooplankton

100%
Dzierzbicka-Glowacka L.
Polish Journal of Environmental Studies
|
2006
|
tom 15
|
nr 2
The influence of turbulence (turbulent kinetic energy dissipation) on predator-prey interactions in zooplankton is discussed with respect to the combined effect of the choice of the turbulent length scale, and size and velocity of predator and prey concentration on the encounter rate. The significance of correct scaling to the turbulent encounter velocity is demonstrated, with three different definitions being considered: the average prey separation, the Kolmogorov scale, and the predator's reactive distance. Numerical investigations using these different definitions of scale were carried out to find the convergence conditions and the behaviour of the scale values for 5-10 mm fish larvae which feed off copepod nauplii in the 10⁴-10⁵ m⁻³ concentration range. The choice of the turbulent length scale is not important for small predator body sizes <5mm and high prey concentrations in the 10⁷-10⁸ m⁻³ range, which are reasonable prey densities for a 1-3 mm copepod (i.e. algae and protozoans). Also in the quasi-laminar regime of water flow (l=2πη) and high prey concentrations, the choice of correct scaling is not important. Predators of any body size will forage in such a regime immovably (swimming velocity v ≈0). However, for large larval lengths >10 mm and prey concentrations <10⁶ m⁻³, the scale can be defined as the average prey separation or as the predator's reactive distance. The effect of turbulence on the encounter rate decreases with the increasing size and velocity of the predator and with prey concentration. A simple one-dimensional prey-predator ecosystem model in the upper mixed layer is presented, which examines the relative importance of turbulence to growth in planktonic consumers. This effect is less for low prey densities <10⁴ m⁻³, when the initial predator biomass and constant growth rate term have a decisive influence. However, the effect of turbulence on the characteristics investigated increases with rising prey density, in which case the controlling factor is encounter rate and in the case of prey concentration, diurnal migration.
15

Influence of the dynamics of turbulent layer on distribution of chlorophyll a in stratifed sea

63%
Dzierzbicka-Glowacka L., Zielinski A.
Ekologia Polska
|
1996
|
tom 44
|
nr 3-4
351-374
16

An algorithm for calculating the concentration of phytoplankton in a stratified sea with respect to the daily migration of zoolpankton. Part 1. P-V-Z-D model

63%
Dzierzbicka-Glowacka L., Zielinski A.
Oceanologia
|
1998
|
tom 40
|
nr 4
17

Growth rate of Pseudocalanus spp. as a function of food concentration, body weight and temperature

63%
Dzierzbicka-Glowacka L., Zielinski A.
Oceanological and Hydrobiological Studies
|
2003
|
tom 32
|
nr 4
18

An algorithm for calculating the concentration of phytoplankton in a stratified sea with respect to the daily migration of zooplankton. Part 2. Numerical simulation

63%
Dzierzbicka-Glowacka L., Zielinski A.
Oceanologia
|
1998
|
tom 40
|
nr 4
19

Numerical studies of the influence of the nutrient regeneration mechanism on the chlorophyll a concentration in a stratified sea

63%
Dzierzbicka-Glowacka L., Zielinski A.
Oceanologia
|
1997
|
tom 39
|
nr 1
20
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Potential rate of reproduction for some geographically separate populations of Pseudocalanus spp.

63%
Dzierzbicka-Glowacka L., Zielinski A.
Oceanologia
|
2004
|
tom 46
|
nr 1
Quantitative expressions are presented describing the potential reproductive rate per individual female of Pseudocalanus spp. in several different waters (not reduced by food limitation) as a function of both temperature and cephalothorax length of females (one equation for each studied region). The calculations were made for some geographically separate populations of Pseudocalanus spp. from southwest Baffin Island, Nova Scotia, Long Island Sound, Scotland, as well as the southern North Sea and its adjacent waters (e.g. the English Channel). On the basis of the findings presented in this work and from other studies, the reproductive rate was computed as the mean number of eggs per sac divided by 1.25 times the embryonic duration at the given temperature. Also computed was the amount of egg matter produced per day as a percentage of body carbon (and dry weight) of female weight for all localities. The relationships for females from the southern North Sea were obtained for ‘viable eggs’, but they should be treated with reserve. A more suitable expression describing egg production in the southern North Sea is the equation for females from the English Channel obtained here. Our assumptions and approximations appear to predict quite well the temperature-length of female dependent daily rates of egg production of well-fed females of Pseudocalanus spp. for the above waters, and we suggest that they can be used to test the hypothesis more thoroughly.
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