Preferencje help
Polish version English version Język
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 6

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych:  trophic relation
help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
1

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

100%
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.
2

Functional diversity, trophic relations and nutrient cycling in psammon community of an eutrophic lake

100%
Kalinowska K., Ejsmont-Karabin J.
Polish Journal of Ecology
|
2012
|
tom 60
|
nr 3
3

Mycobiota of dead Ulmus glabra wood as breeding material for the endangered Rosalia alpina (Coleoptera: Cerambycidae)

100%
Bartnik C., Michalcewicz J., Ledwich D., Ciach M.
Polish Journal of Ecology
|
2020
|
tom 68
|
nr 1
4

Change in metazooplankton abundance in response to flood dynamics and trophic relations in Danubian floodplain lake (Kopacki Rit, Croatia)

80%
Galir A., Palijan G.
Polish Journal of Ecology
|
2012
|
tom 60
|
nr 4
This study investigated relationships of hydrological variability and potential food resources for metazooplankton groups: rotifers, cladocerans, copepods and nauplii. Samples were collected monthly during ice-free season from March until November in 2006. Two sampling stations were chosen, the one located in Lake Sakadaš, as a segment of Kopački Rit floodplain (Croatia), and the other in the River Danube. Due to hydrological conditions we divided our samples into two hydrological groups which corresponded to: 1/ increased water level i.e. disturbed phase and 2/ decreased water level representing a more stable phase. Abundance of metazooplankton was not significantly different between hydrological groups in the River Danube. However, it was significantly different between hydrological groups in Lake Sakadaš (one-way ANOSIM R = 0.688, P = 0.024), where during a decreased water level higher abundance of metazooplankton was recorded. Rotifers were the most abundant metazooplankton group during the whole investigated period at both stations and between both hydrological groups comprising almost 99% of total metazooplankton abundance. Rotifers were significantly positively correlated with the total number of bacteria, as well as with ammonium and total phosphorous concentrations. The metazooplankton community in Lake Sakadaš was negatively influenced by flooding, but not in the River Danube. Compared to the River Danube the investigated floodplain lake showed potential as a storage zone for metazooplankton development during more stable hydrological periods. During that time abundance of rotifers was related to the heterotrophic component of microbial food web. Hence, this investigation adds to the understanding of the metazooplankton dynamics in riverfloodplain systems as well as of their relations with trophic levels under variable hydrological conditions.
5
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Zooplankton structure in high latitude fjords with contrasting oceanography (Hornsund and Kongsfjorden, Spitsbergen)

80%
Ormanczyk M. R., Gluchowska M., Olszewska A., Kwasniewski S.
Oceanologia
|
2017
|
tom 59
|
nr 4
Zooplankton inhabiting the Hornsund and Kongsfjorden fjords on Spitsbergen (Svalbard) were investigated in summer 2013. The goal of the study was to determine how the zooplankton communities vary in environments functioning under different oceanographic regimes. Sampling was conducted with nets of different mesh size and selectivity (56 μm WP-2, 180 μm MultiNet, and 1000 μm Tucker Trawl), which permitted comparing a wide size spectrum of zooplankton components. Species composition did not differ substantially between the fjords, but the zooplankton in Hornsund was almost two times less numerous, and it had lower biomass per unit volume. The highest abundance at both sites was in the smallest zooplankton size fraction found only in samples taken with 56 μm mesh WP-2 net. These comprised as much as 71% and 58% of the total zooplankton abundance in Hornsund and Kongsfjorden, respectively. The communities in both fjords had comparable contributions of Arctic and boreo-Arctic species biomass in the year of the study. However, the comparison of zooplankton characteristics over several years showed changes in abundance and biogeographic structure that corresponded with variations in the physical environments of the fjords. The results of the study permit predicting the possible effects of the increasing influence of Atlantic waters on zooplankton communities inhabiting Arctic marine pelagic ecosystems.
6

An attempt at modelling the production of freshwater fishes of the Vistula Lagoon taking into account trophic relations

80%
Horbowy J.
Natural Sciences
|
1998
|
tom 01
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.