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1

Energetic asymmetry connected with energy flow changes in response to eutrophication: a study of multiple fish species in subtropical shallow lakes

100%
Fu H., Zhang H., He L., Sha Y., Zhao K., He Y., Xu J.
Polish Journal of Ecology
|
2019
|
tom 67
|
nr 4
2

Model of energy flow in the bottom sediments of littoral zone of a dam reservoir with regard to detritivorous roach, Rutilus rutilus [L.]

100%
Starzecka A., Bednarz T., Amirowicz A.
Polish Journal of Ecology
|
1999
|
tom 47
|
nr 1
3

Biomass distribution and dynamics and food web relations in psammon community of a eutrophic lake

84%
Kalinowska K., Ejsmont-Karabin J., Gorelysheva Z., Rybak J. I.
Polish Journal of Ecology
|
2012
|
tom 60
|
nr 3
Organisms living in submerged sand along the shore and below the water’s edge in freshwater lake beaches create community called hydropsammon (see Fig. 1 in Preface). Trophic relations between psammon food web components are essential in energy flow, nutrient cycling and functioning of aquatic environments. The seasonal changes in algal, bacterial, nanoflagellate, ciliate, rotifer and crustacean biomass were investigated in hydroarenal (submerged sand) of the eutrophic Lake Mikołajskie (Poland). Sampling cores were taken once or twice a month since April till October 2005 from three layers: adjacent water layer (AWL), layer of water and sand from the transitory level (EPIH – epihydroarenal) and slice of sand (ENDOH – endohydroarenal). The meanannual phytopsammon biomass was extremely high in all microlayers. Bacterial biomass was the highest in the ENDOH. Biomass of nanoflagellates was 4 to 8 times lower than that of bacteria and was the highest in the AWL. The highest mean annual biomass of ciliates was recorded in the EPIH, whereas rotifers dominated in the ENDOH. In contrast, average biomass of Crustacea was the highest in the AWL. Crustaceans dominated heterotrophic biomass in the AWL and EPIH (92 and 54% of the total biomass, respectively) whereas bacteria definitely prevailed in the ENDOH (57%). The ratios of autotrophic to heterotrophic biomass and prey to predator biomass as well as trophic relations between the studied groups of psammon organisms differed clearly among microlayers. The AWL was characterised by the lowest autotrophic/heterotrophic and predator/prey biomass ratios (about 2) and significant positive correlations between nanoflagellates and ciliates as well as between protists and both rotifers and copepods. The highest autotrophic/heterotrophic and predator/prey biomass ratio (14 and 40, respectively) and lack of correlations was found in the ENDOH. These results may suggest that the pressure of consumers was weaker in the hydroarenal layers than in the AWL. In addition, it seems that psammon ciliates, rotifers and crustaceans inhabiting the ENDOH were probably limited by factors other than food availability. In contrast to the pelagic ecosystems, autotrophic biomass exceeded heterotrophic biomass, especially in the ENDOH.
4
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Energy flows in PSII as an alternative indicator of winter damages of wheat plants: a mass-scale approach

84%
Sasal M., Sniegowska K., Rapacz M.
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
|
2013
|
tom 94
|
nr 3
5

The mass and energy exchange in the surface layers of the soil and atmosphere

84%
Lesny J., Olejnik J.
Acta Agrophysica. Rozprawy i Monografie
|
2010
|
nr 2[179]
6
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Primary productivity of Kumshi reservoir, Kalaburagi District, Karnataka

84%
Fameeda S., Rajashekhar M., Parveen Z., Vijaykumar K.
International Letters of Natural Sciences
|
2015
|
tom 44
In the present investigation, primary productivity of Kumshi reservoir of Kalburagi District has been studied for the period of two years (2012-2014). The results reveals that, gross primary productivity of Kumshi reservoir followed an increasing trend through the northeast monsoon season towards summer season, whereas, net primary productivity of Kumshi reservoir is followed a more or less similar trend of increasing towards northeast monsoon season and summer season, while community respiration of reservoir also followed a similar trend of oscillation increasing trend towards summer and northeast monsoon season during the study period.
7

The role of protozoan communities in freshwater and soil ecosystems

84%
Schonborn W.
Acta Protozoologica
|
1992
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tom 31
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nr 1
8
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Fine organic particles in a sandy beach system (Puck Bay, Baltic Sea)

84%
Kotwicki L., Weslawski J. M., Szaltynis A., Stasiak A., Kupiec A.
Oceanologia
|
2005
|
tom 47
|
nr 2
A total of over 550 samples of particulate organic matter (POM) were obtained from swash and groundwater samples taken on a monthly basis from seven localities on the sandy shores of Puck Bay in 2002 and 2003. Sandy sediment cores from the swash zone were collected to assess the amount of POM in the pore waters. The mean annual concentrations of POM varied between localities from 20 to 500 mg in groundwater and from 6 to 200 mg dm−3 in swash water. The carbon/nitrogen (C/N) ratio in suspended matter was always higher in groundwater (annual mean 12) than in swash water (annual mean 7). The C/N ratio indicates a local, algal origin of POM in the shallow coastal zone.
9
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Deposition of large organic particles (macrodetritus) in a sandy beach system (Puck Bay, Baltic Sea)

84%
Kotwicki L., Weslawski J. M., Raczynska A., Kupiec A.
Oceanologia
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2005
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tom 47
|
nr 2
The aim of this study was to evaluate the amount of organic macrodetritus deposited on the sandy shores of the southern Baltic,an d to determine the type of washout material and their chemical composition (carbon and nitrogen). Over 900 samples of macrodetritus (particles retained on a 0.5 mm sieve) were collected from seven sampling locations along a 120 km stretch of coastline in Poland at monthly intervals in 2002. Analysis of the C and N content of several categories of detritus supplied information about seasonal changes in and the ageing of algal debris,an d indicated that the amount of carrion is constant; the latter is apparently always metabolised very rapidly. The annual deposition of macroalgal detritus on this coast was estimated at 15 000 tonnes fresh weight,t hat is around 75% of the primary production of filamentous macroalgae in Puck Bay. In comparison with the amounts of kelp deposited on sandy beaches in South Africa (Griffiths & Stenton-Dozey 1981),t he massive seaweed washouts on Mediterranean beaches (Morand & Briand 1996),or the deposition of algal mats in the northern Baltic (Norkko & Bonsdorff 1996a),t he quantities of macrodetritus on the shore in the study area are average,ev en allowing for the fact that the Baltic Sea is highly eutrophic (HELCOM 2005).
10

Chironomid production in four lowland rivers [Central Poland]

84%
Grzybkowska M., Temech A., Dukowska M.
Polskie Archiwum Hydrobiologii
|
1996
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tom 43
|
nr 2
11

The importance of ciliates as a trophic link in shallow, brackish and eutrophic lakes

67%
Rychert K., Wielgat-Rychert M., Szczurowska D., Myszka M., Bochynska M., Krawiec K.
Polish Journal of Ecology
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2012
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tom 60
|
nr 4
The importance of ciliates as a trophic link, which is defined as a fraction of the energy bound by primary producers that is transferred through the ciliate community, was assessed in the pelagic zones of shallow, eutrophic, and estuarine lakes. The study was conducted in Lake Gardno and Lake Łebsko located in northern Poland. Each of these lakes is characterized by very high mean annual ciliate biomasses of 115 μg C -1 (Lake Gardno, April 2006 – April 2007), 107 μg C L-1 (Lake Gardno, February 2007 – February 2008), 85 μg C L-1 (Lake Łebsko, April – November 2007), and 127 μg C L-1 (Lake Łebsko, April – September 2008). Ciliate production was estimated using allometric equations and was compared to primary production measured with the light-and-dark bottles method. Annual, depth-integrated ciliate secondary production corresponded to 9 and 11% (Lake Gardno, two consecutive years studied) and 12% (Lake Łebsko, the same value for two growing seasons studied) of primary production. These values exceed the majority of other estimates in the literature, which indicates the high importance of ciliates in such highly-productive, shallow lakes.
12

Energy flow through the algal and bacterial communities in the surface layer of bottom sediments of the River Raba and Dobczyce Reservoir [Southern Poland]

67%
Bednarz T., Starzecka A.
Acta Hydrobiologica
|
1997
|
tom 39
|
nr 1-2
The biomass, production, respiration of algae and heterotrophic bacteria were determined in the surface layer (0.5 cm) of bottom sediments in the river above and below the reservoir, and in the backwater and littoral zone of the reservoir during the vegetation periods (April-October) in 1993 and 1994. The amounts of energy flowing (assumed as the sum of biomass, production, and respiration) through algae and bacteria communities at particular stations were respectively 64-387 and 39-142 kJ m-2 d-1. From the pool of total energy bio- accumulated by heterotrophic bacteria and algae, 87-98% originated from algae, but from the pool of energy released 76-97% was due to heterotrophic bacteria.
13

The basic paths of energy flow and matter transformations in a lowland dam reservoir ecosystem

67%
Zurek R.
Oceanological and Hydrobiological Studies
|
2007
|
tom 36
|
nr Suppl.2
14
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Statystyczno-fizyczne modele przeplywu masy i energii w osrodku porowatym

51%
Usowicz B.
Acta Agrophysica
|
2000
|
tom 29
1-112
he exchange of mass and energy taking place in a porous medium is the main goal of studies of many scientific branches and agrophysics belongs to them. This process is measured and calculated as the quantity of mass and energy transferred from one thermodynamic system to another and is to be determined on the basis of its transport properties. A new statistical model of the mass and energy transfer has been formulated in this paper on the bases of the most fundamental conceptions and ideas of mechanics, thermodynamics and electrodynamics. This new model makes possible the description of connection between the properties of the porous medium and the directly measured physical values. The model enabled for consideration of the following porous medium properties:electrical properties of the porous medium from the viewpoint of determination of its salinity on the basis of the measured bulk electrical conductivity and determination of its moisture content from the measurement of the porous medium dielectric constant, hydraulic, pneumatic and diffusive properties of porous medium resulting in determination of its gas and water conductivity as well as in determination of its diffusivity from the water retention curves, thermal properties of the porous medium leading to determination of its thermal conductivity from the basic properties of solid, liquid and gas phases forming this medium. The calculations based on this new statistical model and comparison of the calculated results with the data measured as well as statistical analysis can be a basis to the statement, that this model predicts the mass and energy transfer with the satisfactory accuracy. This procedure confirms correctness of the assumptions introduced and simplifications used during its construction as well as permits for the statement that the parameters were fitted properly.
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