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Tytuł:
Characterization of light absorption coefficient of red Noctiluca scintillans bloom in the South Eastern Arabian Sea
Autorzy:
Shaju, S.S.
Akula, R.R.
Jabir, T.
Powiązania:
https://bibliotekanauki.pl/articles/48637.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
Noctiluca scintillans
bloom
dinoflagellate
phytoplankton absorption
upwelling
light absorption
food chain
Arabian Sea
Źródło:
Oceanologia; 2018, 60, 3
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modelling the light absorption properties of particulate matter forming organic particles suspended in sea water. Part 3. Practical applications
Autorzy:
Wozniak, B.
Wozniak, S.B.
Tyszka, K.
Ostrowska, M.
Ficek, D.
Majchrowski, R.
Dera, J.
Powiązania:
https://bibliotekanauki.pl/articles/47909.pdf
Data publikacji:
2006
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
marine environment
absorption coefficient
light index
sea water
particulate organic matter
modelling
light absorption
Źródło:
Oceanologia; 2006, 48, 4
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Two models for absorption by coloured dissolved organic matter (CDOM)
Autorzy:
Schwarz, J.N.
Kowalczuk, P.
Kaczmarek, S.
Cota, G.F.
Mitchell, B.G.
Kahru, M.
Chavez, F.P.
Cunningham, A.
McKee, D.
Gege, P.
Kishino, M.
Phinney, D.A.
Raine, R.
Powiązania:
https://bibliotekanauki.pl/articles/47774.pdf
Data publikacji:
2002
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
ocean colour
coloured dissolved organic matter
surface water
coastal water
spectrophotometric measurement
ultraviolet absorption
absorption
Vistula River
Opis:
The standard exponential model for CDOM absorption has been applied to data from diverse waters. Absorption at 440 nm (ag440) ranged between close to zero and 10 m−1, and the slope oft he semilogarithmic absorption spectrum over a minimum range of400 to 440 nm (s440) ranged between <0.01 and 0.04 nm−1. No relationship was found between ag440 or s440 and salinity. Except in the southern Baltic, s440 was found to have a broad distribution (0.0165 ± 0.0035), suggesting that it should be introduced as an additional variable in bio-optical models when ag440 is large. An alternative model for CDOM absorption was applied to available high quality UV-visible absorption spectra from the WisGla river (Poland). This model assumes that the CDOM absorption spectrum comprises distinct Gaussian absorption bands in the UV, similar to those ofb enzene. Five bands were fit to the data. The mean central energy ofal l bands was higher in early summer (E ∼7.2, 6.6, 6.4, 6.2 and 5.5 eV or 172, 188, 194, 200 and 226 nm) than in winter. The higher energy bands were found to decay in both height and width with increasing salinity, while lower energy bands broadened with increasing salinity. s440 was found to be correlated with shape parameters of the bands centred at 6.4 and 5.5 eV. While the exponential model is convenient for optical modelling and remote sensing applications, these results suggest that the Gaussian model offers a deeper understanding ofc hemical interactions affecting CDOM molecular structure.
Źródło:
Oceanologia; 2002, 44, 2
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Light absorption by phytoplankton in the Southern Baltic and Pomeranian lakes: mathematical expressions for remote sensing applications
Autorzy:
Meler, J.
Ostrowska, M.
Ficek, D.
Zdun, A.
Powiązania:
https://bibliotekanauki.pl/articles/48072.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
light absorption
phytoplankton
absorption property
surface water
Baltic Sea
Pomeranian lake
photosynthetic pigment
chlorophyll a
remote sensing
Opis:
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.
Źródło:
Oceanologia; 2017, 59, 3
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Spectral light absorption by yellow substance in the Kattegat-Skagerrak area
Autorzy:
Hojerslev, N.K.
Aas, E.
Powiązania:
https://bibliotekanauki.pl/articles/48244.pdf
Data publikacji:
2001
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
yellow substance
wavelength
spectral slope
coastal water
Kattegat area
absorption coefficient
Scandinavian fjord
Baltic Sea
optical property
Skagerrak area
light absorption
Opis:
More than 1500 water samples were taken from the Kattegat, the Skagerrak and adjacent waters. The value of the absorption coefficient of yellow substance at 310 nm was found to varyf rom 0.06 to 7.4 m−1 in the open coastal waters, with a mean value of 1.3 m−1. The corresponding wavelength-averaged value (250–450 nm) of the semilogarithmic spectral slope of the coefficient ranges from 0.008 to 0.042 nm−1, and the mean value is 0.023 nm−1. Closer to river discharges, as in the fjords, the values of the slope seem to be more constant at around 0.0175±0.0015 nm−1. In this area the slope must then be known in order to compare absorption at different wavelengths or to model the yellow substance absorption.
Źródło:
Oceanologia; 2001, 43, 1
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of accessory pigment composition on the absorption characteristics of a dinoflagellate bloom in a coastal embayment
Autorzy:
Vijayan, A.K.
Somayajula, S.A.
Powiązania:
https://bibliotekanauki.pl/articles/48187.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
pigment composition
light absorption
dinoflagellate
Noctiluca scintillans
bloom
chlorophyll a
non-photosynthetic pigment absorption
high performance liquid chromatography
eutrophic water
Manila Bay
Źródło:
Oceanologia; 2014, 56, 1
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Spectra of light absorption by phytoplankton pigments in the Baltic; conclusions to be drawn from a Gaussian analysis of empirical data
Autorzy:
Ficek, D.
Kaczmarek, S.
Ston-Egiert, J.
Wozniak, B.
Majchrowski, R.
Dera, J.
Powiązania:
https://bibliotekanauki.pl/articles/47835.pdf
Data publikacji:
2004
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
phytoplankton pigment
remote sensing algorithm
Baltic Sea
Gaussian analysis
light absorption
Opis:
Analysed by differential spectroscopy, 1208 empirical spectra of light absorption apl(λ) by Baltic phytoplankton were spectrally decomposed into 26 elementary Gaussian component bands. At the same time the composition and concentrations of each of the 5 main groups of pigments (chlorophylls a, chlorophylls b, chlorophylls c, photosynthetic carotenoids and photoprotecting carotenoids) were analysed in 782 samples by HPLC. Inspection of the correlations between the intensities of the 26 elementary absorption bands and the concentrations of the pigment groups resulted in given elementary bands being attributed to particular pigment groups and the spectra of the mass-specific absorption coefficients established for these pigment groups. Moreover, balancing the absorption effects due to these 5 pigment groups against the overall absorption spectra of phytoplankton suggested the presence of a sixth group of pigments, as yet unidentified (UP), undetected by HPLC. Apr eliminary mathematical description of the spectral absorption properties of these UP was established. Like some forms of phycobilins, these pigments are strong absorbers in the 450–650 nm spectral region. The packaging effect of pigments in Baltic phytoplankton was analysed statistically, then correlated with the concentration of chlorophyll a in Baltic water. As a result, a Baltic version of the algorithm of light absorption by phytoplankton could be developed. This algorithm can be applied to estimate overall phytoplankton absorption spectra and their components due to the various groups of pigments from a knowledge of their concentrations in Baltic water.
Źródło:
Oceanologia; 2004, 46, 4
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Parameterization of light scattering for solving the inverse problem of determining the concentrations of the principal light scattering and absorbing admixtures in shelf waters
Autorzy:
Pelevin, V.N.
Rostovtseva, V.V.
Powiązania:
https://bibliotekanauki.pl/articles/48226.pdf
Data publikacji:
2001
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
bio-optical modelling
backscattering
sea water
shelf water
light absorption
irradiance
Opis:
A method for estimating the water backscattering coefficient was put forward on the basis of experimental data of diffuse attenuation coefficient for downwelling irradiance and irradiance reflectance. Calculations were carried out for open sea waters of different types and the spectral dependencies were found (‘anomalous’ spectra) and explained. On this basis, a new model of light backscattering on particles in the sea is proposed. This model may be useful for modelling remote sensing reflectance spectra in order to solve the inverse problems of estimating the concentration of natural admixtures in shelf waters.
Źródło:
Oceanologia; 2001, 43, 4
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modelling the light absorption properties of particulate matter forming organic particles suspended in seawater. Part 2. Modelling results
Autorzy:
Wozniak, B.
Wozniak, S.B.
Tyszka, K.
Ostrowska, M.
Majchrowski, R.
Ficek, D.
Dera, J.
Powiązania:
https://bibliotekanauki.pl/articles/47522.pdf
Data publikacji:
2005
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
light absorption coefficient
sea water
particulate organic matter
particulate matter
organic substance
Źródło:
Oceanologia; 2005, 47, 4
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Luminescence and photosynthesis of marine phytoplankton - a brief presentation of new results
Autorzy:
Wozniak, B.
Dera, J.
Powiązania:
https://bibliotekanauki.pl/articles/47916.pdf
Data publikacji:
2000
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
marine phytoplankton
pigment
luminescence
chlorophyll a
photosynthetic pigment
interaction
phytoplankton
light absorption
photosynthesis
Opis:
This volume contains a set of eight papers presenting the results of the latest research into the interaction of light with marine phytoplankton by teams from the Marine Physics Department at the IO PAS in Sopot, and the Department of Environmental Physics at the Pedagogical University of Słupsk. These results were presented at the ‘Second Workshop on Luminescence and Photosynthesis of Marine Phytoplankton’ (Sopot–Paraszyno, 11–15 October 1999) sponsored by the Polish State Committee for Scientific Research. This introductory article discusses the most important assumptions and objectives of the research, and outlines the latest results. These are subsequently discussed in detail in the following papers: (1) Majchrowski & Ostrowska, Influence of photo- and chromatic acclimation on pigment composition in the sea, (2) Woźniak et al., Model of the ‘in vivo’ spectral absorption of algal pigments. Part 1. Mathematical apparatus, (3) Majchrowski et al., Model of the ‘in vivo’ spectral absorption of algal pigments. Part 2. Practical applications of the model, (4)Ostrowska et al., Variability of the specific fluorescence of chlorophyll in the ocean. Part 1. Theory of classical ‘in situ’ chlorophyll fluorometry, (5) Ostrowska et al., Variability of the specific fluorescence of chlorophyll in the ocean. Part 2. Fluorometric method of chlorophyll a determination, (6) Ficek et al., Influence of non-photosynthetic pigments on the measured quantum yield of photosynthesis, (7) Ficek et al., Variability of the portion of functional PS2 reaction centres in the light of a fluorometric study. For the reader’s convenience, we append a list of the symbols denoting the physical quantities used in the texts. The nomenclature and denotations are in line with the conventions employed in the subject literature.
Źródło:
Oceanologia; 2000, 42, 2
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Remote sensing of vertical phytoplankton pigment distributions in the Baltic: new mathematical expressions. Part 3: Non-phytosynthetic pigment absorption factor
Autorzy:
Wozniak, B.
Majchrowski, R.
Ostrowska, M.
Ficek, D.
Kunicka, J.
Dera, J.
Powiązania:
https://bibliotekanauki.pl/articles/48371.pdf
Data publikacji:
2007
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
remote sensing
pigment distribution
phytoplankton pigment
vertical distribution
non-photosynthetic pigment absorption
Baltic Sea
Opis:
This paper, part 3 of the description of vertical pigment distributions in the Baltic Sea, discusses the mathematical expression enabling the vertical distributions of the non-photosynthetic pigment absorption factor fa to be estimated. The factor fa is directly related to concentrations of the several groups of phytoplankton pigments and describes quantitatively the ratio of the light energy absorbed at given depths by photosynthetic pigments to the light energy absorbed by all the phytoplankton pigments together (photosynthetic and photoprotecting). Knowledge of this factor is highly desirable in the construction of state-of-the-art ‘light-photosynthesis’ models for remote-sensing purposes. The expression enables fa to be estimated with considerable precision on the basis of two surface parameters (available from satellite observations): the total chlorophyll a concentration at the surface Ca(0) and the spectral downward irradiance Ed(λ, 0) just below the sea surface. The expression is applicable to Baltic waters from the surface down to an optical depth of τ ≈5. The verification of the model description of fa was based on 400 quasi-empirical values of this factor which were calculated on the basis of empirical values of the following parameters measured at the same depths: Ed(λ, z) (or also PAR(z)), apl(λ, z), and the concentrations of all the groups of phytoplankton pigments Ca(z) and Cj(z) (where j denotes in turn chl b, chl c, PSC, phyc, PPC). The verification shows that the errors in the values of the non-photosynthetic pigment absorption factor fa estimated using the model developed in this work are small: in practice they do not exceed 4%. Besides the mathematical description of the vertical distribution of fa, this paper also discusses the range of variation of its values measured in the Baltic and its dependence on the trophic index of a basin and depth in the sea. In addition, the similarities and differences in the behaviour of fa in Baltic and oceanic basins are compared.
Źródło:
Oceanologia; 2007, 49, 4
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Chlorophyll fluorimetry as a method for studying light absorption by photosynthetic pigments in marine algae
Autorzy:
Matorin, D.N.
Antal, T.K.
Ostrowska, M.
Rubin, A.B.
Ficek, D.
Majchrowski, R.
Powiązania:
https://bibliotekanauki.pl/articles/48459.pdf
Data publikacji:
2004
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
alga
chlorophyll a concentration
photosynthetic pigment
fluorescence
marine alga
phytoplankton
light absorption
chlorophyll fluorimenty
Opis:
Using laboratory cultures of algae and natural phytoplankton populations from Nhatrang Bay (South China Sea), the relationship between the chlorophyll fluorescence F0, the chlorophyll a concentration Ca and light absorption capacities of algae cells was studied. It is shown that the ratio F0/Ca depends mainly on the species composition of the algae population; hence, the concentration Ca can be measured with the fluorescence method with acceptable accuracy only when the species composition of algae populations varies over a rather narrow range. The fluorescence F0 can, however, be a good index of the total absorption capacities of different phytoplankton species, because the intensity of F0 depends on the sum total of light absorbed by all photosynthetic pigments in a plant cell. Thus, the fluorescence F0 measures not only the concentration of chlorophyll a, but that of all photosynthetic pigment concentrations.
Źródło:
Oceanologia; 2004, 46, 4
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modelling of bio-optical parameters of open ocean waters
Autorzy:
Pelevin, V.N.
Rostovtseva, V.V.
Powiązania:
https://bibliotekanauki.pl/articles/48307.pdf
Data publikacji:
2001
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
yellow substance
chlorophyll pigment
pigment
suspended matter
bio-optical modelling
ocean water
light absorption
Opis:
An original method for estimating the concentration of chlorophyll pigments, absorption of yellow substance and absorption of suspended matter without pigments and yellow substance in detritus using spectral diffuse attenuation coefficient for downwelling irradiance and irradiance reflectance data has been applied to sea waters of different types in the open ocean (case 1). Using the effective numerical single parameter classification with the water type optical index m as a parameter over the whole range of the open ocean waters, the calculations have been carried out and the light absorption spectra of sea waters tabulated. These spectra are used to optimize the absorption models and thus to estimate the concentrations of the main admixtures in sea water. The value of m can be determined from direct measurements of the downward irradiance attenuation coefficient at 500 nm or calculated from remote sensing data using the regressions given in the article. The sea water composition can then be readily estimated from the tables given for any open ocean area if that one parameter m characterizing the basin is known.
Źródło:
Oceanologia; 2001, 43, 4
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Performance evaluation of non-water absorption coefficient partitioning algorithms in optically complex coastal waters of Kochi and Goa, India
Autorzy:
Kolluru, S.
Gedam, S.S.
Inamdar, A.B.
Powiązania:
https://bibliotekanauki.pl/articles/2078824.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
absorption coefficient
phytoplankton
coloured dissolved organic matter
partitioning
algorithm
coastal water
particulate matter
optical property
India
Opis:
Absorption coefficient partitioning algorithms (APAs) were developed to partition the total absorption coefficient (a(λ)) or total non-water absorption coefficient (anw (λ)) into the absorption subcomponents, i.e., absorption due to phytoplankton aph(λ), colored dissolved organic matter (CDOM) ag(λ) and non-algal particulate matter ad (λ), λ is the wavelength. Absorption coefficients of CDOM and non-algal particulate matter are generally combined due to a similarity in exhibited spectral shape and represented as colored detrital matter (CDM) absorption coefficient, adg(λ). This study focuses on the applicability of five APAs Schofield’s, Lin’s, Zhang’s, Stacked Constraints Model (SCM) and Generalized Stacked Constraints Model (GSCM), in deriving the absorption subcomponents from anw (λ) in optically complex coastal waters of Kochi and Goa, India. The average spectral Mean Absolute Percentage Errors (MAPE) obtained for all models in the retrieval of aph(λ), ad (λ), ag(λ) and adg(λ) lie in the ranges of 26—44%, 37—45%, 34—65% and 42—56%. Slopes of adg(λ), ag(λ) and ad (λ) as indicated by Sdg, Sg and Sd are derivable from GSCM, Schofield and Lin’s models only. GSCM model exhibited good retrieval capability of Sd with MAPE values of 22% and a correlation coefficient of 0.74. In retrieval of Sg parameter, none of the models demonstrated satisfactory performance. Overall, the GSCM and Schofield’s models demonstrated good performance in the retrieval of absorption subcomponents, aph(λ), adg(λ), ad (λ) and Sd. Effect of applying baseline correction to ad (λ) on model performance is studied. Tuning with in situ data can further improve the absorption subcomponent and slope parameter retrieval capability of the models.
Źródło:
Oceanologia; 2021, 63, 4; 420-437
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł

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