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281.
ABSTRACT

A paleoecological study was performed on a sediment core recovered from a former artificial lake – the Reedbed of Sic near Cluj-Napoca, Romania – in order to explore the history of water management and nearby salt mining, and its impact on the environment. From the Roman period, the area served as a recipient of salty wastewaters. The most significant shift in the sediment composition and macrofossil assemblages took place after 1000 AD, suggesting a significant upturn in salt mining. The impact of mining-related activities was further increased in the Middle Ages when, according to documentary sources, fishponds and watermills were constructed in the area. They led to the stabilisation of the water level in the lakebed, and enhanced the appearance of reed beds and the spread of secondary salt marsh vegetation. This biotop was later invaded by the Entzia macrescens, an agglutinated foraminiferal taxon, known mostly from the high intertidal marshes worldwide. In the investigated marshland, the dominance of halophytic species reached their acme in the seventeenth century, which coincides with the acme of mining activities. This medieval – early Modern Age industrial ecosystem survived the abandonment of salt mines and fishponds, being preserved until today.  相似文献   
282.
Abstract

The Australian Mesozoic fish fauna is considered to be depauperate in comparison with fish faunas in the Northern Hemisphere. However, due to its geographical location as a potential radiation center in the Southern Hemisphere, Australia’s Mesozoic fish fauna is important for understanding fish radiations. Most of the modern fish groups originated during the Mesozoic, but the first records of a modern fish fauna (freshwater and marine) in Australia does not occur until the lower Paleogene. Here, we review all known fossil fish-bearing localities from the Mesozoic of Australia, to improve the understanding of the record. The apparent low Australian Mesozoic fish diversity is likely due to its understudied status of the constituent fossils rather than to a depauperate record. In addition, we review recent work with the aim of placing the Australian Mesozoic fish fauna in a global context. We review the taxonomy of Australian fossil fishes and conclude that the assignments of many actinopterygians need major revision within a modern phylogenetic context. The vast majority of chondrichthyans are yet to be formally described; to the contrary all of the known lungfish specimens have been described. This study considers the microscopic and fragmented remains of Mesozoic fish already found in Australia, allowing a more complete view of the diversity of the fishes that once inhabited this continent.

Rodney W. Berrell [], School of Earth and Planetary Sciences, Curtin University, Kent Street, Bentley, Western Australia, 6102, Australia; Catherine Boisvert [], School of Molecular and Life Sciences (MLS), Curtin University, Kent Street, Bentley, Western Australia, 6102, Australia; Kate Trinajstic [], School of Molecular and Life Sciences (MLS), Curtin University, Kent Street, Bentley, Western Australia, 6102, Australia; Mikael Siversson# [], Department of Earth and Planetary Sciences, Western Australian Museum, 49 Kew Street, Welshpool, Western Australia, 6106, Australia; Jesús Alvarado-Ortega [], Instituto Geologia Cd universitaria, Circuito de la investigacion, Del. coyoacan, C.P. 04510, Ciudad de México, México; Lionel Cavin [], Section of Earth Sciences, Muséum d’Histoire naturelle de la Ville de Genèeve, CP 6434, 1211 Genève 6, Switzerland; Steven W. Salisbury [], School of Biological Sciences, The University of Queensland, Brisbane St Lucia, Queensland, 4072, Australia; Anne Kemp [], 9 Hampton Grove, Norwood, Adelaide, South Australia 5067, Australia. #Also affiliated with: School of Molecular and Life Sciences, Curtin University, Kent Street, Bentley, WA 6102, Australia.  相似文献   
283.
284.
Aspects of 2nd- to 5th-century ce Roman production technology and knowledge transfer in southern Austria (known as Noricum) were examined. With no evidence for workshops identified in the study area, 44 grey ware bowls from two sites at Aguntum and Lavant were studied macroscopically, and combined with optical microscopy, X-ray powder diffraction, prompt gamma activation, neutron activation and scanning electron microscopy, in order to understand whether one (large) workshop supplied these bowls, or whether the bowls were produced by several (small) workshops nearby. Combined with information from the geological background, the results were used to tentatively indicate the production location. The results indicate that the grey ware bowls from Aguntum and Lavant were produced by local workshops nearby. The bowls were manufactured with similar clay sources, tempered with crushed calcite-marble rocks from the Tauern Window, their surface smoothed and burnished, and fired between 800 and 850°C in a reducing atmosphere of an open fire. This is taken to suggest that Roman potters, who were located at Aguntum and Lavant, shared strategies of raw materials selection, paste preparation, finishing and firing, and transferred technological knowledge through time.  相似文献   
285.
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