Wyniki wyszukiwania - AGRO

1

Structural characteristics and primary production of the herb layer in Sphagno girgensohnii-Piceetum Pol. 1962 community

100%

Kotowska J.

Polish Ecological Studies

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1995

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tom 21

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nr 2

2

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Microphytobenthic primary production along a non-tidal sandy beach gradient: an annual study from the Baltic Sea

100%

Urban-Malinga B., Wiktor J.

Oceanologia

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2003

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tom 45

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nr 4

The microphytobenthic primary production and chlorophyll a content were studied over the annual cycle (May 1998 – May 1999) on a non-tidal Baltic sandy beach at three stations along the beach gradient: littoral, waterline and splash zone. The chlorophyll a concentrations varied between 0.88 and 12.18 μg cm−3. Net and gross primary production rates respectively lay within the ranges 0.1–31.4 mgC m−2 h−1 and 0.2–41.8 mgC m−2 h−1. The highest values of both Chl a content and primary production were noted at the littoral station, the lowest ones at the waterline. The mean annual P/B ratio was highest at the waterline. The differences in Chl a content between stations were statistically significant and may be related to water dynamics, resuspension and water content. Production rates were highly variable on monthly time scales, and the highest results at all the study locations were noted in July. The gross photosynthetic rates were significantly correlated with water temperature.

3

Measurement of phytoplankton photosynthesis rate using a pump-and-probe fluorometer

86%

Antal T. K., Venediktov P. S., Matorin D. N., Ostrowska M., Wozniak B., Rubin A. B.

Oceanologia

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2001

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tom 43

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nr 3

291-313

In this work we have studied the possibility of determining the rate of phytoplankton photosynthesis in situ using a submersible pump-and-probe fluorometer in water areas differing in their trophic level, as well as in climatic and hydrophysical characteristics. A biophysical model was used to describe the relationship between photosynthesis, underwater irradiance, and the intensity of phytoplankton fluorescence excited by an artificial light source. Fluorescence intensity was used as a measure of light absorption by phytoplankton and for assessing the efficiency of photochemical energy conversion at photosynthetic reaction centers. Parameters of the model that could not be measured experimentally were determined by calibrating fluorescence and irradiance data against the primary production measured in the Baltic Sea with the radioactive carbon method. It was shown that the standard deviation of these parameters in situ did not exceed 20%, and the use of their mean values to estimate the phytoplankton photosynthetic rate showed a good correlation between the calculated and measured data on primary production in the Baltic (r = 0.89), Norwegian (r = 0.77) and South China (r = 0.76) Seas.

4

Primary production in Ezcurra Inlet during the Antarctic summer of 1977/78

86%

Hapter R., Wozniak B., Dobrowolski K.

Oceanologia

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1983

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tom 15

5

Structural features and primary production of the herb layer in the Carici elongatae-Alnetum Koch. 1926 community

86%

Pasternak-Kusmierska D.

Polish Ecological Studies

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1995

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tom 21

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nr 2

6

Spectral effects in bio-optical control on the ocean system

86%

Sathyendranath S., Platt T.

Oceanologia

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2007

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tom 49

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nr 1

The influence of phytoplankton on the spectral structure of the submarine irradiance field is reviewed. The implications for the ocean system of the spectral response by phytoplankton to the ambient light field are discussed. For example, it provides the basis for retrieval of phytoplankton biomass by visible spectral radiometry (ocean-colour remote sensing). In the computation of primary production, the results of spectral models differ in a known and systematic manner from those of non-spectral ones. The bias can be corrected without risk of incurring additional random errors. The models in use for phytoplankton growth, whether based on available light or absorbed light, whether expressed in terms of chlorophyll or carbon, are shown all to conform to the same basic formalism with the same parameters. Residual uncertainty lies less with the models than with the parameters required for their implementation. The submarine light field and the spectral characteristics of phytoplankton carry latent information on phytoplankton community structure. Differences in spectral response by different functional types of phytoplankton are small but significant. Optical considerations limit the maximum phytoplankton biomass that can be sustained in a given surface mixed layer. Moreover, the upper bound on the biomass depends on the spectral response of the dominant phytoplankton taxa. As a result, an optical control exists in the mixed layer that tends to resist extreme excursions of the biomass and also to maintain biodiversity in the phytoplankton.

7

Structural characteristics and primary production of the herb layer in the Tilio-Carpinetum Tracz. 1962 community

86%

Pasternak-Kusmierska D., Kotowska J.

Polish Ecological Studies

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1995

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tom 21

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nr 2

8

The dependence between bacterial production and environmental conditions in the Gulf of Gdańsk

86%

Ameryk A., Podgorska B., Witek Z.

Oceanologia

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2005

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tom 47

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nr 1

Bacterial production, primary production and a number of other environmental factors were measured during six cruises in the Gulf of Gdańsk conducted in various seasons from 1995 to 2001. Bacterial production (BP) in the epipelagic layer ranged from 1.5% (April) to 80% (July) of the gross primary production (PP). Significant differences were observed between the BP/PP ratios in estuarine and open-water areas. The highest values were recorded in the coastal area and near the mouth of the river Vistula. It suggests that allochthonous organic matter has a great influence on BP. The correlations between particular parameters and regression analyses indicated that BP in the Gulf of Gdańsk depended on temperature, organic nitrogen concentration, PP, chlorophyll a concentration, organic phosphorus concentration, salinity and biochemical oxygen demand. Of all the independent variables, the temperature had the greatest impact on BP (R2 = 0.62). There was an inverse parabolic relationship between bacterial production and temperature. It appears that above a temperature of 12◦C bacterial production depended on substrates to a higher degree than on temperature. The negative correlation between BP and concentrations of mineral nitrogen and phosphorus in the annual cycle were probably due to an indirect dependence. A multiple regression equation, which included temperature and organic phosphorus concentrations, explained 78% of the variation in BP. Increasing BP resulted in an increasing biomass of bacterivorous nanoflagellates and of bacterivorous ciliates, which is indicative of bottom-up control in this segment of the trophic chain.

9

Primary production and chlorophyll a concentration during upwelling events along the Hel Peninsula [the Baltic Sea]

86%

Zalewski M., Ameryk A., Szymelfenig M.

Oceanological and Hydrobiological Studies

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2005

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tom 34

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nr Suppl.2

10

Impact of silicates and detergents on primary production and total biomass of algae in a short-term laboratory experiment

86%

Ciesielczuk T., Czerniawska-Kusza I.

Archiwum Ochrony Środowiska

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2006

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tom 32

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nr 3

11

Primary production in the Southern Baltic Sea determined from photosynthetic light curves

86%

Renk H., Ochocki S.

Bulletin of the Sea Fisheries Institute

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1999

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nr 3

12

Distributions of photosynthetic and photoprotecting pigment concentrations in the water column in the Baltic Sea: an improved mathematical description

72%

Ston-Egiert J., Majchrowski R., Ostrowska M.

Oceanologia

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2019

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tom 61

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nr 1

13

Spatial distribution of biological and physical sediment parameters in the Western Gulf of Gdansk

72%

Huzarska K.

Oceanologia

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2013

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tom 55

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nr 2

14

Comparison of primary production and pelagic community respiration rates in the coastal zone of the Gulf of Gdańsk

72%

York J. K., Witek Z., Labudda S., Ochocki S.

Oceanologia

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2001

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tom 43

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nr 3

365-370

The organic matter production/respiration balance in the coastal water column was examined, both the primary production and community respiration being measured with the oxygen light-and-dark bottle method. Community respiration (CR) was always lower than the gross primary production (GPP) measured at a standard light intensity of 390 μE m−2 s−1, which amounted, on average, to 30% of GPP. During most of the in situ sampling period, the coastal system (6–7 m depth) was found to be autotrophic, with depth-integrated GPP ranging from 6.7 mmoles O2 m−2 d−1 in December to 214.2 mmoles O2 m−2 d−1 in August, and CR ranging correspondingly from 6.0 to 177.7 mmoles O2 m−2 d−1. However, on some occasions heterotrophic conditions were recorded: depth-integrated GPP

15

Potential determinants of Clostridium spp. occurrence in Polish silage

72%

Goldsztejn M., Grenda T., Koziel N., Sapala M., Mazur M., Sieradzki Z., Krol B., Kwiatek K.

Journal of Veterinary Research

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2020

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tom 64

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nr 4

16

Algorithm for the remote sensing of the Baltic ecosystem (DESAMBEM). Part 1: Mathematical apparatus

72%

Wozniak B., Krezel A., Darecki M., Wozniak S. B., Majchrowski R., Ostrowska M., Kozlowski L., Ficek D., Olszewski J., Dera J.

Oceanologia

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2008

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tom 50

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nr 4

451-508

This article is the first of two papers on the remote sensing methods of monitoring the Baltic ecosystem, developed by our team. Earlier, we had produced a series of detailed mathematical models and statistical regularities describing the transport of solar radiation in the atmosphere-sea system, the absorption of this radiation in the water and its utilisation in a variety of processes, most importantly in the photosynthesis occurring in phytoplankton cells, as a source of energy for the functioning of marine ecosystems. The comprehensive DESAMBEM algorithm, presented in this paper, is a synthesis of these models and regularities. This algorithm enables the abiotic properties of the environment as well as the state and the functioning of the Baltic ecosystem to be assessed on the basis of available satellite data. It can be used to determine a good number of these properties: the sea surface temperature, the natural irradiance of the sea surface, the spectral and spatial distributions of solar radiation energy in the water, the surface concentrations and vertical distributions of chlorophyll a and other phytoplankton pigments in this sea, the radiation energy absorbed by phytoplankton, the quantum efficiency of photosynthesis and the primary production of organic matter. On the basis of these directly determined properties, other characteristics of processes taking place in the Baltic ecosystem can be estimated indirectly. Part 1 of this series of articles deals with the detailed mathematical apparatus of the DESAMBEM algorithm. Part 2 will discuss its practical applicability in the satellite monitoring of the sea and will provide an assessment of the accuracy of such remote sensing methods in the monitoring of the Baltic ecosystem (see Darecki et al. 2008 – this issue).

17

Evaluation of primary production of phytoplankton based on chlorophyll delayed fluorescence in sea water

72%

Zvalinsky V. I., Bekasova O. D., Kaczmarek S., Kosakowska A.

Oceanologia

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1990

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tom 28

18

Primary production of the Southern Baltic in 1979-1983

72%

Renk H.

Oceanologia

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1990

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tom 29

19

Microphytobenthic primary production on exposed coastal sandy sediments of the Southern Baltic Sea using ex situ sediment cores and oxygen optodes

72%

Kuriyama K., Grundling-Pfaff S., Diehl N., Woelfel J., Karsten U.

Oceanologia

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2021

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tom 63

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nr 2

20

Spatio-temporal variability of the size-fractionated primary production and chlorophyll in the Levantine Basin (Northeastern Mediterranean)

72%

Yucel N.

Oceanologia

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2018

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tom 60

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nr 3

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