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Tytuł:
Kopalne zygospory glonów Zygnemataceae (Chlorophyta) z osadów górnego miocenu KWB Bełchatów
Fossil zygospores of Zygnemataceae algae (Chlorophyta) from the Upper Miocene of the Bełchatów Lignite Mine
Autorzy:
Worobiec, E.
Worobiec, G.
Powiązania:
https://bibliotekanauki.pl/articles/2074571.pdf
Data publikacji:
2008
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
analiza pyłkowa
glony słodkowodne
zygospory
glonów Zygnemataceae
tafonomia
paleoekologia
górny miocen
Bełchatów
pollen analysis
freshwater algae
zygospores
Zygnemataceae
taphonomy
paleoecology
Upper Miocene
Opis:
The Zygnemataceae are an extant family of freshwater filamentous green algae which produce acid-resistant zygospores. Palynomorphs of probable zygnematacean affinity occur in sediments of the Carboniferous to Holocene age (van Geel & Grenfell, 1996). These algae reproduce using four types of spores, but only zygospores and probably aplanospores are acid-resistant and can be preserved in the fossil record. The majority of recent species have zygospores of constant form of three types: elliptical (occurring in genera Debarya and Spirogyra), square (occurring in Mougeotia) or circular (occurring in Zygnema). The zygospores normally have a three-layered wall (exospore, mesospore and endospore), but only mesospore contains a decay and acid-resistant substance (most probably algaenans), so usually only this layer is preserved in fossil state, and is of interest to palynologists. The mesospore layer is smooth or ornamented with various sculptures (Kadłubowska, 1972; Grenfell, 1995). The shape and sculpture are very important features for determination of both the recent and fossil species. Two samples from the Bełchatów Lignite Mine were palynologically examined and two types of probable fossil zygnematacean zygospores, differing in shape, were encountered. The following species have been distinguished: Tetraporina sp., Spintetrapidites quadriformis Krutzsch & Pacltová as well as Ovoidites elongatus (Hunger) Krutzsch, and O. ligneolus Potonié ex Krutzsch. The fossil genus Tetraporina is usually related to the recent zygnematacean algae zygospores of Mougeotia genus, fossil Ovoidites is the nearest the recent zygospores of Spirogyra and Sirogonium, while Spintetrapidites is similar to both zygospores of Zygnemataceae and Tetraedron green algae. Species of recent genera Mougeotia and Spirogyra are usually found in shallow, freshwater, oxygen-rich environments such as ponds, lake margins (paludal or low gradient fluvial), ditches and very slowly moving streams (Kadłubowska, 1972). Occurrence of Tetraporina and Ovoidites zygnematacean zygospores in the material studied from Bełchatów points out at presence of water basin(s) during sedimentation time. That confirms the previous geological results that formation of examined sediments took place in the environment of a meandering river (including ox-bow lakes).
Źródło:
Przegląd Geologiczny; 2008, 56, 11; 1000-1004
0033-2151
Pojawia się w:
Przegląd Geologiczny
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Cysty Dinoflagellata z górnego kampanu i najniższego mastrychtu (górna kreda) profilu środkowej Wisły - stratygrafia i paleoekologia
Dinoflagellate cysts from the upper Campanian–lowermost Maastrichtian (Upper Cretaceous) of the Middle Vistula River section - stratigraphy and palaeoecology
Autorzy:
Nechwedowicz, Mariusz
Powiązania:
https://bibliotekanauki.pl/articles/20197905.pdf
Data publikacji:
2022
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
cysty bruzdnicowe
taksonomia
biostratygrafia
paleoekologia
zmiany poziomu morza
chłodzenie
Kampan
Mastrycht
górna kreda
środkowaj Wisła
Polska
dinoflagellate cysts
taxonomy
biostratigraphy
palaeoecology
sea-level changes
cooling
Campanian/Maastrichtian boundary
Upper Cretaceous
Middle Vistula River section
Polska
Opis:
Among the rich dinoflagellate cyst assemblages recovered from the upper Campanian-lowermost Maastrichtian succession of the Middle Vistula River section (central Poland), four taxa (Callaiosphaeridium bicoronatum, Odontochitina dilatata, Oligosphaeridium araneum and Samlandia paucitabulata) have been described as new. An analysis of the distribution of particular dinoflagellate cyst taxa enabled the development of a highly resolved biostratigraphic framework, calibrated against other biozonal schemes (based, among others, on inoceramid bivalves, ammonites and belemnites), formerly established for the succession. A comparison of the Middle Vistula River record with the dinoflagellate cyst ranges documented in other European successions enabled correlations with selected sections in Belgium, the Netherlands, southern Germany and northern Italy, and with the Campanian/Maastrichtian boundary stratotype section in Tercis les Bains, southwest France. A palaeoecological analysis of the dino- flagellate cyst assemblages and of other components of phytoplankton communities revealed a well-defined trend in sea-level fluctuations (likely of eustatic origin), and palaeoclimatic changes probably related to the latest Cretaceous cooling episode, as observed elsewhere.
Źródło:
Przegląd Geologiczny; 2022, 70, 10; 751-760
0033-2151
Pojawia się w:
Przegląd Geologiczny
Dostawca treści:
Biblioteka Nauki
Artykuł
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