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W przyrodzie istnieje cała gama organizmów, podobnych do porostów, składających się z dwóch lub większej liczby komponentów, które tworzą odrębną jednostkę. Należą do nich m.in. plazińce Symsagittifera roscoffensis, których ciało wypełniają glony Tetraselmis convolutae, czy największy z małży - przydacznia olbrzymia, która żywi się głównie dzięki symbiotycznym glonom Zooxanthella. Tego typu jednostki to swego rodzaju „niedokończone" gatunki, powstające w wyniku współpracy odrębnych form życia.
Coral reefs are the most productive ecosystems on Earth. They ensure the conservation of biodiversity and are a live habitat for 25% of all marine organisms. The main relationship on the coral reef is the symbiosis between corals and algae from the genus Symbiodinium (commonly called zooxanthellae). The authors of this publication have characterized and described the factors limiting the occurrence of coral reefs, including: water temperature, salinity, access to sunlight, contamination, physicochemical and hydromechanical parameters of water. Moreover anthropogenic threats to coral reefs have been specified, including diving tourism, ecological disasters (e.g. oil spills) and the development of marine aquaristics. Rapid changes in the basic living conditions are dangerous for corals and their symbionts and may cause the unsuitability of the new environment resulting in diseases such as coral bleaching. Corals bleaching is a disease associated with the break of the coral and algae relationship which results in a coral reef death on a global scale. Awareness of these negative factors, often related to human activity, may allow us to better understand the ecological processes that are the basis of reef functioning and might enable us to prevent and oppose to the changes and ecological recessions of coral reefs.
The small solitary coral dominated, Grypophyllum-Chostophyllum association, a pioneer coral community, is widely distributed at the base of the Givetian Burdekin Formation of north Queensland in the mixed arkose-carbonate sediments. It is succeeded by fasciculate coral dominated, Dendrostella trigemne association, which is mainly associated with wackestone or bioclastic calcirudite of inner shelf, lagoonal or protected environments. The Australophyllum-Sanidophyllum association, Blysmatophyllunt-Iotuaphgllum schlueteri association, and Spongophgllstm association, all dominated by in situ, large massive coral colonies, formed biostromal deposits on the margins of the basin. They developed in nearshore environments during the maximum flooding in the region. The Aphyllum salmoni-Stringophgllum (Neospongophyllum) bipartitum association indicates relatively deeper, mid-outer shelf environments connected with maximum flooding in the depocentre and least terrigenous influx. The massive coral dominated Endophyllum columna-Stringophyllum (Stringophyllum) isactis association, developed in the initial regressive phase, forms a distinctive biostromal unit at the top of the Burdekin Formation. The Lekanophyllum association developed at the base of the Cultivation Gully Formation in a very shallow nearshore environment with a large terrigendus influx as a result of the basin wide, relatively rapid regression. It is characterised by the abundant occurrence of solitary corals and large sized, cerioid Endophyllum columna, which often formed micro-atolls. Rugose corals were better adapted than stromatoporoids to survive of mud inllux.
Struktury wapienne wytwarzane przez koralowce są podstawą do powstawania unikatowego ekosystemu, znanego jako rafa koralowa. Koralowce żyją w obligatoryjnej symbiozie z glonami. Spełniają one niezwykle ważne usługi ekosystemowe, wycenione na 6 bln funtów rocznie. Różne aspekty ludzkiej działalności są dzisiaj przyczyną ich ginięcia. Około połowy raf koralowych wykazuje silne i bardzo silne oddziaływanie. Konieczne są zdecydowane działania prawne i edukacyjne w ich obronie.
Tabulate corals and single species each of the heliolitid anthozoans and chaetetid sclerosponges mostly from the Givetian and Frasnian stromatoporoid-coral series of the Holy Cross Mts and the Silesia-Cracow Region are reviewed from an ecological and stratigraphical point of view. Thamnopora, or the branched pachyporids, and massive alveolitids are usually the most significant reef-builders. The most distinctive fauna, with Caliapora battersbyi and Heliolites porosus, thrived in the earlier Givetian bank habitats. Late Givetian biostromal-complex associations with Alveolites obtortus, Striatopora enigmatica, and especially Alveolitella fecunda, as well as the succeeding Frasnian Alveolites-dominated reef-complex faunas with A. maillieuxi, and later with A. tenuissimus, Aulocystis and syringoporids, are far more uniform. In addition, a local Coenites laminosa-Chaetetes yunnanensis fauna is recognized in the Middle Givetian of the Kostomłoty area. The transitional biogeographic position for Polish tabulate assemblages between Variscan Europe and Russia is clearly evident. Forty eight species have been identified. Pachyfavosites polonicus sp. n., Striatopora enigmatica sp. n., Alveolitella polygona sp. n., Armalites minimus sp. n., and Syringoporella raritabulata sp. n., Alveolites edwardsi frasnianus subsp. n., and Caliapora battersbyi minor subsp. n. are proposed.
Givetian and Frasnian stromatoporoid-coral limestone of the Kowala Formation in the southern Holy Cross Mts is subdivided stratigraphically, and correlated with strata elsewhere on the basis of identified sea-level cyclicity, with support from conodonts and other selected benthic fossils. After the Eifelian hypersaline sabkha phase, an extensive two-step regional colonization of the Kielce Region carbonate platform took place during the Eifelian/Givetian passage interval and the Middle Givetian. At least four deepening pulses resulted in intermittent drowning of the vast carbonate platform and sequential replacement of the undifferentiated Stringocephalus biostromal bank by the Sitkówka bank complex and, subsequently, by the Dyminy reef complex. The reef developed in the central Dyminy belt as result of the early Frasnian accelerated sea-level rise after some period of biotic stagnation near the Givetian-Frasnian boundary. Final demise of the reef resulted from combined eustatic and tectonic movements during the late Frasnian major crisis interval.
Rugose corals of the Givetian to Lower Frasnian Kowala limestone Formation in the environs of Chęciny, SW Holy Cross Mts and in its age equivalents in the Silesian-Cracow region of Southern Poland represent five distinct assemblages of restricted time-and-space distribution. Within the Stringocephalus Beds the high diversity Pseudohexagonaria(?) laxa assemblage indicates open-shelf conditions whereas low diversity Temnophyllum occidentale assemblage represents restricted conditions. The transgressive Jaźwica Mbr. locally contains diversified and cosmopolitan Acanthophyllum sp. n. fauna. Following temporally coral assemblages, i.e. Disphyllum (lower Sitkówka and Chęciny Beds) and Macgeea-Thamnophyllum (Kadzielnia Mbr, upper Sitkówka Beds) are mostly biostromes of branching corals of low taxonomical diversity typical for restricted relatively setting, rather unfavorable for rugosans. Exceptional are two Hexagonaria horizons with common massive colonies. Diffiisolasma gen. nov., Sociophyllum severiacum sp. nov., Temnophyllum zamkowae sp. nov. and Hexagonaria hexagona kowalae subsp. nov. are proposed as the new taxa.
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