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1

Pine pollen grains in coastal waters of the Baltic Sea

100%
Pawlik M., Ficek D.
Oceanological and Hydrobiological Studies
|
2016
|
tom 45
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nr 1
2

Spatial distribution and seasonal variability in chlorophyll concentrations in the coastal Lake Gardno [Poland]

100%
Ficek D., Wielgat-Rychert M.
Oceanological and Hydrobiological Studies
|
2009
|
tom 38
|
nr 1
3-15
3
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Light absorption by phytoplankton in the Southern Baltic and Pomeranian lakes: mathematical expressions for remote sensing applications

81%
Meler J., Ostrowska M., Ficek D., Zdun A.
Oceanologia
|
2017
|
tom 59
|
nr 3
The absorption properties of phytoplankton in surface waters of the Baltic Sea and coastal lakes are examined in the context of their relationships with the concentration of the main photosynthetic pigment, chlorophyll a. The analysis covers 425 sets of spectra of light absorption coefficients aph(l) and chlorophyll a concentrations Chla measured in 2006—2009 in various waters of the Baltic Sea (open and coastal waters, the Gulf of Gdańsk and the Pomeranian Bay, river mouths and the Szczecin Lagoon), as well as in three lakes in Pomerania, Poland (Obłęskie, Łebsko and Chotkowskie). In these waters the specific (i.e. normalized with respect to Chla) light absorption coefficient of phytoplankton aph *(l) varies over wide ranges, which differ according to wavelength. For example, aph *(440) takes values from 0.014 to 0.124 mg1 m2, but aph *(675) from 0.008 to 0.067 mg1 m2, whereby Chla ranges from 0.8 to 120 mg m3. From this analysis a mathematical description has been produced of the specific light absorption coefficient of phytoplankton aph *(l), based on which the dynamics of its variability in these waters and the absorption spectra in the 400—700 nm interval can be reconstructed with a low level of uncertainty (arithmetic statistical error: 4.09—10.21%, systematic error: 29.63—51.37%). The relationships derived here are applicable in local remote sensing algorithms used for monitoring the Baltic Sea and coastal lakes and can substantially improve the accuracy of the remotely determined optical and biogeochemical characteristics of these waters.
4
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Total suspended particulate matter in the Porsanger fjord (Norway) in the summers of 2014 and 2015

81%
Bialogrodzka J., Stramska M., Ficek D., Wereszka M.
Oceanologia
|
2018
|
tom 60
|
nr 1
High-latitude fjords, very vulnerable to global change, are impacted by their land and ocean boundaries, and they may be influenced by terrestrial water discharges and oceanic water inputs into them. This may be reflected by temporal and spatial patterns in concentrations of biogeochemically important constituents. This paper analyses information relating to the total suspended matter (TSM) concentration in the Porsanger fjord (Porsangerfjorden), which is situated in the coastal waters of the Barents Sea. Water samples and a set of physical data (water temperature, salinity, inherent optical properties) were obtained during two field expeditions in the spring and summer of 2014 and 2015. Bio-optical relationships were derived from these measurements, enabling optical data to be interpreted in terms of TSM concentrations. The results revealed significant temporal variability of TSM concentration, which was strongly influenced by precipitation, terrestrial water discharge and tidal phase. Spatial distribution of TSM concentration was related to the bathymetry of the fjord, dividing this basin into three subregions. TSM concentrations ranged from 0.72 to 0.132 g m−3 at the surface (0–2 m) and from 0.5 to 0.67 g m−3 at 40 m depth. The average mineral fraction was estimated to be 44% at surface and 53% at 40 m.
5

Factors controlling pelagic production and respiration in a shallow polymictic lake

81%
Wielgat-Rychert M., Rychert K., Ficek D.
Polish Journal of Ecology
|
2010
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tom 58
|
nr 2
Shallow lakes, defined as ‘nonstratifying’, polymictic water bodies are usually eutrophic and highly productive, and more turbid than deeper lakes due to bottom sediment resuspension. Gross primary production (GPP) and total planktonic community respiration (TCR) were measured in a very shallow (on average 1.2 m deep) and large (area 25 km²), polymictic, eutrophic Lake Gardno (Baltic coastal lake, Northern Poland) with the light-and-dark bottle method. The aim was to compare GPP to TCR ratio in the pelagic zone in a course of a year and identify factors governing these processes. Identified factors governing GPP were light conditions and temperature, with Q₁₀ = 2.23 in the 2–24.5°C temperature range, whereas TCR was driven by water temperature (Q₁₀ = 2.15 in the same temperature range) and by organic matter content in water. TCR was correlated with total suspended matter (effect of bottom sediment resuspension due to wind action in a very shallow lake), however not with chlorophyll content. During two-year measurement period (years 2006 and 2007), annual GPP amounted to 402 and 471 g C m⁻², and TCR amounted to 192 and 223 g C m⁻² respectively. Lake Gardno pelagic system seemed to be net autotrophic on annual basis; GPP to TCR ratio = 2.1. Part of the organic matter produced in pelagial is probably deposited in bottom sediments decomposed there. Wind induced resuspension increases matter content in water (measured here as TSM content) and thus contributes to pelagic respiration processes (TCR).
6
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Remote sensing reflectance of Pomeranian lakes and the Baltic

81%
Ficek D., Zapadka T., Dera J.
Oceanologia
|
2011
|
tom 53
|
nr 4
7
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UV absorption reveals mycosporine-like amino acids (MAAs) in Tatra Mountain lake phytoplankton

81%
Ficek D., Dera J., Wozniak B.
Oceanologia
|
2013
|
tom 55
|
nr 3
8
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Variability of the specific fluorescence of chlorophyll in the ocean. Part 2. Fluorometric method of chlorophyll a determination

81%
Ostrowska M., Matorin D. N., Ficek D.
Oceanologia
|
2000
|
tom 42
|
nr 2
Two methods of determining the chlorophyll a concentration in the sea have been formulated on the basis of artificially induced fluorescence measured with the aid of submersible fluorometers. The method of statistical correlation is founded on the empirical relationship between fluorescence and chlorophyll concentration. The theoretical model of fluorescence described in Part 1 of this paper (see Ostrowska et al. 2000, this volume) provides the basis of the other method, the physical method. This describes the dependence of the specific fluorescence of phytoplankton on the chlorophyll concentration, a diversity of photophysiological properties of phytoplankton and the optical characteristics of the fluorometer. In order to assess their practicability, the methods were subjected to empirical verification. This showed that the physical method yielded chlorophyll concentrations of far greater accuracy. The respective error factors of the estimated chlorophyll concentration were x = 2.07 for the correlation method and x = 1.5 for the physical method. This means that the statistical logarithmic error varies from −52 to +107% in the case of the former method but only from −33 to +51% in the case of the latter. Thus, modifying the methodology has much improved the accuracy of chlorophyll determinations.
9
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Influence of non-photosynthetic pigments on the measured quantum yield of photosynthesis

81%
Ficek D., Majchrowski R., Ostrowska M., Wozniak B.
Oceanologia
|
2000
|
tom 42
|
nr 2
The aim of this work was to assess the effect of non-photosynthetic (photoprotecting) pigments on the measured quantum yield of photosynthesis in the sea. The energy absorbed by these pigments is not utilised during photosynthesis. As a result, the measured yield of this process, i.e. the photosynthetic yield referred to the total energy absorbed by all phytoplankton pigments, is less than the actual quantum yield of photosynthesis, i.e. the yield referred to the energy absorbed by photosynthetic pigments only. The model of the absorption properties of marine phytoplankton derived by the authors (see Woźniak et al. 2000, this volume) was employed to determine the relevant contributions of photosynthetic and non-photosynthetic pigments to the total energy absorbed by phytoplankton in different trophic types of seas and at different depths in the water column. On this basis the non-photosynthetic pigment absorption factor fa, which describes the relation between the true and measured quantum yields of photosynthesis, could be characterised. The analysis shows that fa varies in value from 0.33 to 1, and that it depends on the trophic type of sea and the depth in the water column. The values of this factor are usually highest in eutrophic waters and decrease as waters become progressively more oligotrophic. It is also characteristic of fa that it increases with increasing depth in the sea.
10
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Variability of the portion of functional PS2 reaction centres in the light of a fluorometric study

81%
Ficek D., Ostrowska M., Kuzio M., Pogosyan S. I.
Oceanologia
|
2000
|
tom 42
|
nr 2
The paper contains a preliminary analysis of the links between the portion fc of functional PS2 reaction centres in the photosynthetic apparatus of marine phytoplankton and environmental factors. The analysis is based inter alia on fluorometric measurements of fc (see Kolber & Falkowski 1993) in water sampled from different depths and trophic types of sea. From the statistical generalisations was derived an analytical form of the relationship between fc, and the optical depth and trophic type of sea (the trophicity index was taken to be the surface concentration of chlorophyll a). According to this relationship, fc rises as the trophicity of the sea does so. Moreover, there is a certain optimal optical depth for each type of water at which the number of functional PS2 reaction centres reaches a maximum. Above or below this depth the value of fc falls. At the present stage of investigations it seems reasonable to assume that this drop in the number of functional PS2 reaction centres close to the surface is due to the destructive effect of excessive irradiance. On the other hand, their reduced number at greater depths, below the fc maximum, can be attributed to the deficit of light and the consequent destruction of reaction centres.
11

Practical applicability and preliminary results of the Baltic environmental satellite remote sensing system (SatBaltyk)

71%
Ostrowska M., Darecki M., Krezel A., Ficek D., Furmanczyk K.
Polish Maritime Research
|
2015
|
tom 22
|
nr 3
The SatBałtyk (Satellite Monitoring of the Baltic Sea Environment) project is being realized in Poland by the SatBałtyk Scientific Consortium, specifically appointed for this purpose, which associates four scientific institutions: the Institute of Oceanology PAN in Sopot – coordinator of the project, the University of Gdańsk (Institute of Oceanography), the Pomeranian Academy in Słupsk (Institute of Physics) and the University of Szczecin (Institute of Marine Sciences). The project is aiming to prepare a technical infrastructure and set in motion operational procedures for the satellite monitoring of the Baltic Sea ecosystem. The main sources of input data for this system will be the results of systematic observations by metrological and environmental satellites such as TIROS N/NOAA, MSG (currently Meteosat 10), EOS/AQUA and Sentinel -1, 2, 3 (in the future). The system will deliver on a routine basis the variety of structural and functional properties of this sea, based on data provided by relevant satellites and supported by hydro-biological models. Among them: the solar radiation influx to the sea’s waters in various spectral intervals, energy balances of the short- and long-wave radiation at the Baltic Sea surface and in the upper layers of the atmosphere over the Baltic, sea surface temperature distribution, dynamic states of the water surface, concentrations of chlorophyll a and other phytoplankton pigments in the Baltic waters, spatial distributions of algal blooms, the occurrence of coastal upwelling events, and the characteristics of primary production of organic matter and photosynthetically released oxygen in the water and many others. The structure of the system and preliminary results will be presented
12
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Inherent optical properties and remote sensing reflectance of Pomeranian lakes (Poland)

71%
Ficek D., Meler J., Zapadka T., Wozniak B., Dera J.
Oceanologia
|
2012
|
tom 54
|
nr 4
13

Nutrient fluxes and their impact on the phytoplankton in a shallow coastal lake

71%
Wielgat-Rychert M., Jarosiewicz A., Ficek D., Pawlik M., Rychert K.
Polish Journal of Environmental Studies
|
2015
|
tom 24
|
nr 2
Data on nutrient concentrations and phytoplankton growth was analyzed in Lake Gardno, representing a separate group of coastal lakes within the Polish abiotic typology according to the Water Framework Directive. The aim of this work was to identify sources of nutrient variability in lake water and consequences of this variability for phytoplankton growth. Phytoplankton composition was dominated by green algae, present in high biovolumes throughout the year, and cyanobacteria, whose elevated biovolumes were noted at temperatures above 13ºC. Production of phytoplankton was often light-limited throughout the vegetation period (changing on a day-to-day basis). Low N-to-P ratio, the presence of nitrogen-fixing cyanobacteria, and Carlson’s trophic state indices (TSI) analysis indicated also possible nitrogen limitations of primary production during the vegetation period. No phosphorus limitation was indicated. Possible nitrogen limitation was a result of in-lake modification of the N-to-P ratio compared to external N-to-P ratio in nutrient loads discharged by the freshwater inflow. Lake Gardno was a substantial sink of nitrogen discharged by the Łupawa River, probably due to denitrification. Nutrient budget for the 2006-08 period revealed 50% loss of nitrogen in a lake, whereas the phosphorus budget did not reveal substantial phosphorus retention. From a management perspective, the study indicates the importance of reduction of phosphorus loads discharged to the lake, which could prevent further development of cyanobacterial blooms stimulated by low N-to-P ratio.
14
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Dependence of the photosynthesis quantum yield in oceans on environmental factors

71%
Wozniak B., Dera J., Ficek D., Ostrowska M., Majchrowski R.
Oceanologia
|
2002
|
tom 44
|
nr 4
Statistical relationships between the quantum yield of photosynthesis and selected environmental factors in the ocean have been studied. The underwater irradiance, nutrient content, water temperature and water trophicity (i.e. the surface concentration of chlorophyll Ca(0)) have been considered, utilizing a large empirical data base. On the basis of these relationships, a mathematical model of the quantum yield was worked out in which the quantum yield Φ is expressed as a product of the theoretical maximum quantum yield ΦMAX = 0.125 atomC quanta−1 and six dimensionless factors. Each of these factors fi appears to be, to a sufficiently good approximation, dependent on one or two environmental factors and optical depth at most. The model makes it possible to determine the quantum yield from known values of these environmental factors. Empirical verification of the model yielded a positive result – the statistical error of the approximate values of the quantum yield Φ is 42%.
15
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Quantum yield of photosynthesis in the Baltic: a new mathematical expression for remote sensing applications

71%
Wozniak B., Ficek D., Ostrowska M., Majchrowski R., Dera J.
Oceanologia
|
2007
|
tom 49
|
nr 4
Statistical relationships between the quantum yield of photosynthesis Φ and selected environmental factors in the Baltic have been established on the basis of a large quantity of empirical data. The model formula is the product of the theoretical maximum quantum yield ΦMAX =0.125 atomC quantum−1 and five dimensionless factors fi taking values from 0 do 1: Φ = ΦMAXfa fΔ fc(Ca(0)) fc(PARinh) fE, t. To a sufficiently good approximation, each of these factors fi appears to be dependent on one or at most two environmental factors, such as temperature, underwater irradiance, surface concentration of chlorophyll a, absorption properties of phytoplankton and optical depth. These dependences have been determined for Baltic Case 2 waters. The quantum yield Φ, calculated from known values of these environmental factors, is then applicable in the model algorithm for the remote sensing of Baltic primary production. The statistical error of the approximate quantum yields Φ is 62%.
16

Secchi depth-chlorophyll relationship in the Baltic

61%
Renk H., Nakonieczny J., Ochocki S., Lorenz Z., Majchrowski R., Ficek D.
Acta Ichthyologica et Piscatoria. Supplementum
|
1991
|
tom 21
17
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Model of the in vivo spectral absorption of algal pigments. Part 2. Practical applications of the model

61%
Majchrowski R., Wozniak B., Dera J., Ficek D., Kaczmarek S., Ostrowska M., Koblentz-Mishke O. I.
Oceanologia
|
2000
|
tom 42
|
nr 2
The article describes applications and accuracy analyses of a statistical model of light absorption by phytoplankton that accounts for the influence of photo- and chromatic acclimation on its absorption properties. Part 1 of this work (seeWoźniak et al. 2000, this volume) describes the mathematical apparatus of the model. Earlier models by Woźniak & Ostrowska (1990) and by Bricaud et al. (1995, 1998) are analysed for comparison. Empirical verification of these three models shows that the new model provides a much better approximation of phytoplankton absorption properties than do the earlier models. The statistical errors in estimating the mean absorption coefficient apl, for example, are σ+ = 36% for the new model, whereas for the earlier models the figures are σ+ = 43% (Bricaud et al. 1995, 1998) and σ+ = 59% (Woźniak & Ostrowska 1990). Example applications are given of the new model illustrating the variability in phytoplankton absorption properties with depth and trophicity of the sea.
18
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Remote sensing of vertical phytoplankton pigment distributions in the Baltic: new mathematical expressions. Part 1: Total chlorophyll a distribution

61%
Ostrowska M., Majchrowski R., Ston-Egiert J., Wozniak B., Ficek D., Dera J.
Oceanologia
|
2007
|
tom 49
|
nr 4
This article is the first in a series of three describing the modelling of the vertical different photosynthetic and photoprotecting phytoplankton pigments concentration distributions in the Baltic and their interrelations described by the so-called non-photosynthetic pigment factor. The model formulas yielded by this research are an integral part of the algorithms used in the remote sensing of the Baltic ecosystem. Algorithms of this kind have already been developed by our team from data relating mainly to oceanic Case 1 waters (WC1) and have produced good results for these waters. But their application to Baltic waters, i.e., Case 2 waters, was not so successful. On the basis of empirical data for the Baltic Sea, we therefore derived new mathematical expressions for the spatial distribution of Baltic phytoplankton pigments. They are discussed in this series of articles. This first article presents a statistical model for determining the total concentration of chlorophyll a (i.e., the sum of chlorophylls a+pheo derived spectrophotometrically) at different depths in the Baltic Sea Ca(z) on the basis of its surface concentration Ca(0), which can be determined by remote sensing. This model accounts for the principal features of the vertical distributions of chlorophyll concentrations characteristic of the Baltic Sea. The model’s precision was verified empirically: it was found suitable for application in the efficient monitoring of the Baltic Sea. The modified mathematical descriptions of the concentrations of accessory pigments (photosynthetic and photoprotecting) in Baltic phytoplankton and selected relationships between them are given in the other two articles in this series (Majchrowski et al. 2007, Woźniak et al. 2007b, both in this volume).
19
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Remote sensing of vertical phytoplankton pigment distributions in the Baltic: new mathematical expressions. Part 2: Accessory pigment distribution

61%
Majchrowski R., Ston-Egiert J., Ostrowska M., Wozniak B., Ficek D., Lednicka B., Dera J.
Oceanologia
|
2007
|
tom 49
|
nr 4
This is the second in a series of articles, the aim of which is to derive mathematical expressions describing the vertical distributions of the concentrations of different groups of phytoplankton pigments; these expressions are necessary in the algorithms for the remote sensing of the marine ecosystem. It presents formulas for the vertical profiles of the following groups of accessory phytoplankton pigments: chlorophylls b, chlorophylls c, phycobilins, photosynthetic carotenoids and photoprotecting carotenoids, all for the uppermost layer of water in the Baltic Sea with an optical depth of τ ≈ 5. The mathematical expressions for the first four of these five groups of pigments, classified as photosynthetic pigments, enable their concentrations to be estimated at different optical depths in the sea from known surface concentrations of chlorophyll a. The precision of these estimates is characterised by the following relative statistical errors according to logarithmic statistics σ−: approximately 44% for chlorophyll b, approx. 39% for chlorophyll c, approx. 43% for phycobilins and approx. 45% for photosynthetic carotenoids. On the other hand, the mathematical expressions describing the vertical distributions of photoprotecting carotenoid concentrations enable these to be estimated at different depths in the sea also from known surface concentrations of chlorophyll a, but additionally from known values of the irradiance in the PAR spectral range at the sea surface, with a statistical error σ− of approximately 42%
20
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Model of the in vivo spectral absorption of algal pigments. Part 1. Mathematical apparatus

61%
Wozniak B., Dera J., Ficek D., Majchrowski R., Kaczmarek S., Ostrowska M., Koblentz-Mishke O. I.
Oceanologia
|
2000
|
tom 42
|
nr 2
Existing statistical models of in vivo light absorption by phytoplankton (Woźniak & Ostrowska 1990, Bricaud et al. 1995, 1998) describe the dependence of the phytoplankton specific spectral absorption coefficient a∗ pl(λ) on the chlorophyll a concentration Ca in seawater. However, the models do not take into account the variability in this relationship due to phytoplankton acclimation. The observed variability in the light absorption coefficient and its components due to various pigments with depth and geographical position at sea, requires further accurate modelling in order to improve satellite remote sensing algorithms and interpretation of ocean colour maps. The aim of this paper is to formulate an improved model of the phytoplankton spectral absorption capacity which takes account of the pigment composition and absorption changes resulting from photo- and chromatic acclimation processes, and the pigment package effect. It is a synthesis of earlier models and the following statistical generalisations: (1) statistical relationships between various pigment group concentrations and light field properties in the sea (described by Majchrowski & Ostrowska 2000, this volume); (2) a model of light absorption by phytoplankton capable of determining the mathematical relationships between the spectral absorption coefficients of the various photosynthetic and photoprotecting pigment groups, and their concentrations in seawater (Woźniak et al. 1999); (3) bio-optical models of light propagation in oceanic Case 1 Waters and Baltic Case 2 Waters (Woźniak et al. 1992a, b, 1995a,b). The generalised model described in this paper permits the total phytoplankton light absorption coefficient in vivo as well as its components related to the various photosynthetic and photoprotecting pigments to be determined using only the surface irradiance PAR(0+) surface chlorophyll concentration Ca(0) and depth z in the sea as input data.
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