scholarly journals History of the development of Eemian Interglacial lakes on the basis of Cladocera subfossil analysis (Central and Eastern Poland)

2015 ◽  
Vol 15 (3) ◽  
pp. 85-94
Author(s):  
Monika Niska

Abstract This paper presents the results of Cladocera subfossil analysis using material obtained from five paleolakes of the Eemian Interglacial located in central and north-eastern Poland. Analyses of Cladocera subfossils in Poland and other parts of the world have revealed detailed results covering the last 13,000 years. Cladocera subfossils from sediments older than the last glaciation have been analysed occasionally. The first analyses of older sediments were conducted in Denmark by Frey in 1962. In Poland, the first analyses of this type were conducted on material obtained in Konin. The Eemian lakes subject to the study were formed at the end of the Warta Glaciation in tunnel and kettle holes. A continuous record of environmental changes throughout the Eemian Interglacial until the early Vistulian Glaciation has been preserved in lake sediments. The bottom part of the profile consists of sands and silts, followed by gyttja and peat. The upper part of the profile contains peat and organic shales. Cladocera subfossils found in Eemian sediments were thinner and their structure was more damaged. The low degree of subfossil preservation forced a change in the method of preparation of subfossils for microscopic analysis as required by IGCP Project 158. Cladocera species determined within the studied paleolakes correspond to the present-day species inhabiting the area of Poland and Europe. The species composition and the variability in the frequency of Cladocera specimens made it possible to distinguish discrete phases of lake development associated with changes in temperature and water level, trophic state and the presence of macrophytes. The results of Cladocera analysis are well correlated with data obtained in pollen analyses.

2013 ◽  
Vol 53 (1) ◽  
pp. 3-8 ◽  
Author(s):  
Katarzyna Pochocka-Szwarc

ABSTRACT The morphology of the Mazury Lake District (north-eastern Poland) dates from 24-19 ka (main stadial of the youngest Vistulian glaciation). During this last glacial maximum (MIS 2) a belt with lacustrine basins was formed when the ice sheet retreated at the end of the Pomeranian phase. The ice-sheet retreat is morphologically also expressed by the occurrence of end moraines. The study area is situated in the Skaliska Basin, in the northern part of the Lake District (near the Polish/ Russian border), at the periphery of zone with end moraines. Originally the basin was an ice-dammed depression filled with melt water; the water flowed out into the developing Pregoła valley when the ice retreated and did no longer dam off the depression. The basin, which is surrounded by hill-shaped moraines, is filled now with Late Glacial and Holocene glaciolacustrine sediments. The organic sediments of the basin record the history of the Late Glacial and Holocene climatic changes in this region.


1964 ◽  
Vol 15 (1) ◽  
pp. 5-39
Author(s):  
Burkhard Frenzel

Abstract. A method for pollenanalytical investigations of loesses is described. If several sources of error are duely taken into consideration, this method is successful in the reconstruction of the vegetation history of those phases of pleniglacial times, during which the thick loess layers were accumulated. The method can be employed in pollenanalytical investigations of weathered and unweathered loesses, with the exception of redeposited loesses. It can be shown that the famous sequence of fossil soils at Oberfellabrunn, known as the soils of the "Fellabrunner Komplex" („Stillfried A"), which is sometimes held to be the equivalent of the "Göttweig Interstadial", must be divided into the brown loamy soil at the base of the sequence, which was formed during the Eemian Interglacial, and into the younger humic layers, which developed during the Interstadials of Amersfoort and Brørup. The amelioration of climate during the "Stillfried B-Interstadial" (perhaps equivalent of the "Paudorf Interstadial"?) was strong enough to enable local subalpine conifer forests and riverine broad-leaved forests to spread along the rivers and other suitable places within the still dominant steppe formations on the drier loess plateaus. The loess layers of the Riss and Würm glaciations have been accumulated within the eastern Dart of Niederösterreich in different steppe communities, which can be described at best as belonging to the Gramineae steppe formation, rich in herbaceous plants. Sometimes there occurred plants of recent tundra-communities in the loess steppe: but real tundras did not exist at that time in Niederösterreich. This holds true most of all for the last period of loess accumulation after the Stillfried B-Interstadial. When being compared with pollen spectra of surface samples of recent tundra, steppe and semidesert plant communities, it becomes evident, that the open vegetation, thriving during the last glaciation in vast regions of Northern Eurasia cannot be described in terms of modern plant associations.


2019 ◽  
Vol 2 ◽  
pp. 89-93 ◽  
Author(s):  
Achim Brauer ◽  
Markus J. Schwab ◽  
Brian Brademann ◽  
Sylvia Pinkerneil ◽  
Martin Theuerkauf

Abstract. Tiefer See formed in a subglacial gully system at the end of the last glaciation in the northeast German lowlands. The lake has been selected as a focus site within the TERENO (Terrestrial Environmental Observatory) NE German observatory because it forms annual laminations (calcite varves) providing detailed information of past climate and environmental changes. Our research integrates palaeolimnology and limnology by combining high-resolution analyses of the sediment record with a comprehensive monitoring of the lake and its sedimentation processes since 2012. This allows evaluation of the observed effects of ongoing climate change in the context of the long-term history of the lake. The lacustrine sediment profile comprises the last 13 000 years and is dated by a multiple dating approach. The sedimentation is dominated by biochemical calcite formation and algal blooms. Detrital material from the catchment forms only a minor component even during times of increased human impact. Repeated changes between well-varved, poorly varved and homogeneous sediment intervals indicate that sedimentation processes in the lake are particularly sensitive to changes in lake circulation. The research at Tiefer See is embedded in ICLEA (https://www.iclea.de, last access: 2 August 2019) and BaltRap (https://www.io-warnemuende.de/projekt/167/baltrap.html, last access: 2 August 2019) projects.


PalZ ◽  
2021 ◽  
Author(s):  
Xingliang Zhang ◽  
Degan Shu

AbstractThe Cambrian Explosion by nature is a three-phased explosion of animal body plans alongside episodic biomineralization, pulsed change of generic diversity, body size variation, and progressive increase of ecosystem complexity. The Cambrian was a time of crown groups nested by numbers of stem groups with a high-rank taxonomy of Linnaean system (classes and above). Some stem groups temporarily succeeded while others were ephemeral and underrepresented by few taxa. The high number of stem groups in the early history of animals is a major reason for morphological gaps across phyla that we see today. Most phylum-level clades achieved their maximal disparity (or morphological breadth) during the time interval close to their first appearance in the fossil record during the early Cambrian, whereas others, principally arthropods and chordates, exhibit a progressive exploration of morphospace in subsequent Phanerozoic. The overall envelope of metazoan morphospace occupation was already broad in the early Cambrian though it did not reach maximal disparity nor has diminished significantly as a consequence of extinction since the Cambrian. Intrinsic and extrinsic causes were extensively discussed but they are merely prerequisites for the Cambrian Explosion. Without the molecular evolution, there could be no Cambrian Explosion. However, the developmental system is alone insufficient to explain Cambrian Explosion. Time-equivalent environmental changes were often considered as extrinsic causes, but the time coincidence is also insufficient to establish causality. Like any other evolutionary event, it is the ecology that make the Cambrian Explosion possible though ecological processes failed to cause a burst of new body plans in the subsequent evolutionary radiations. The Cambrian Explosion is a polythetic event in natural history and manifested in many aspects. No simple, single cause can explain the entire phenomenon.


The Holocene ◽  
2021 ◽  
pp. 095968362110032
Author(s):  
Halinka Di Lorenzo ◽  
Pietro Aucelli ◽  
Giuseppe Corrado ◽  
Mario De Iorio ◽  
Marcello Schiattarella ◽  
...  

The Garigliano alluvial-coastal plain, at the Latium-Campania border (Italy), witnessed a long-lasting history of human-environment interactions, as demonstrated by the rich archaeological knowledge. With the aim of reconstructing the evolution of the landscape and its interaction with human activity during the last millennia, new pollen results from the coastal sector of the Garigliano Plain were compared with the available pollen data from other nearby sites. The use of pollen data from both the coastal and marine environment allowed integrating the local vegetation dynamics within a wider regional context spanning the last 8000 years. The new pollen data presented in this study derive from the analysis of a core, drilled in the coastal sector, which intercepted the lagoon-marshy environments that occurred in the plain as a response to the Holocene transgression and subsequent coastal progradation. Three radiocarbon ages indicate that the chronology of the analyzed core interval ranges from c. 7200 to c. 2000 cal yr BP. The whole data indicate that a dense forest cover characterized the landscape all along the Prehistoric period, when a few signs of human activity are recorded in the spectra, such as cereal crops, pasture activity and fires. The main environmental changes, forced by natural processes (coastal progradation) but probably enhanced by reclamation works, started from the Graeco-Roman period and led to the reduction of swampy areas that favoured the colonisation of the outer plain.


2010 ◽  
Vol 122 (2) ◽  
pp. 130 ◽  
Author(s):  
Ruth E. Lawrence ◽  
Marc P. Bellette

The Rushworth Forest is a Box and Ironbark open sclerophyll forest in central Victoria that has been subject to a long history of gold mining activity and forest utilisation. This paper documents the major periods of land use history in the Rushworth Forest and comments on the environmental changes that have occurred as a result. During the 1850s to 1890s, the Forest was subject to extensive gold mining operations, timber resource use, and other forest product utilisation, which generated major changes to the forest soils, vegetation structure and species cover. From the 1890s to 1930s, concern for diminishing forest cover across central Victoria led to the creation of timber reserves, including the Rushworth State Forest. After the formation of a government forestry department in 1919, silvicultural practices were introduced which aimed at maximising the output of tall timber production above all else. During World War II, the management of the Forest was taken over by the Australian Army as Prisoner of War camps were established to harvest timber from the Forest for firewood production. Following the War, the focus of forestry in Victoria moved away from the Box and Ironbark forests, but low value resource utilisation continued in the Rushworth Forest from the 1940s to 1990s. In 2002, about one-third of the Forest was declared a National Park and the other two-thirds continued as a State Forest. Today, the characteristics of the biophysical environment reflect the multiple layers of past land uses that have occurred in the Rushworth Forest.


1996 ◽  
Vol 33 (7) ◽  
pp. 1075-1086 ◽  
Author(s):  
Trevor Bell

The last glaciation of Fosheim Peninsula is reconstructed on the basis of landform and sediment mapping and associated radiocarbon dates. Ice growth involved the expansion of cirque glaciers and accumulation on upland surfaces that are now ice free. Limited ice buildup, despite lowering of the paleoglaciation level by 700–800 m, is attributed to the hyperaridity of the region during glacial conditions. Marine deposits in formerly submerged basins beyond the ice margins are interpreted to represent (i) sedimentation caused by local ice buildup and marine transgression by 10.6 ka BP, (ii) increased ablation and glacier runoff [Formula: see text]9.5 ka BP, and (iii) marine regression during the Holocene. Holocene marine limit reaches a maximum elevation of approximately 150 m asl along northern Eureka Sound and Greely Fiord and descends southeastwards to 139–142 m asl near the Sawtooth Mountains. A synchronous marine limit is implied where the last ice limit was inland of the sea. The magnitude and pattern of Holocene emergence cannot be fully explained by the glacioisostatic effects of the small ice load during the last glaciation of the region. Deglaciation of the peninsula was underway by 9.5 ka BP; however, local ice caps may have persisted through the wannest period of the Holocene until 6–5 ka BP. This was likely a function of reduced sea ice conditions and increased moisture availability which benefited low-lying coastal icefields, but had negligible effect on interior highland ice caps.


2020 ◽  
pp. 7-32
Author(s):  
Katarzyna Kulczyńska ◽  
Natalia Borowicz ◽  
Karolina Piwnicka-Wdowikowska

Morasko University Campus in Poznań – origin, spatial and functional structure, transport solutions The purpose of the paper is to characterize the most recently created part of the Adam Mickiewicz University – the Morasko Campus. The paper consists of three parts. The first concerns the origins and development of the campus. The second part presents its spatial and functional structure on the basis of a field inventory, while the third one – campus transport solutions based on a survey conducted among students. The history of the campus located in the northern, peripheral part of the city began with laying the foundation act and the cornerstone in 1977. The agricultural role of this area, dominant until the 1980s, has been replaced with new functions, mainly academic and scientific ones. The first university buildings were commissioned in the 1990s, and the construction boom began after 2000. A total of nine faculties (out of 21 existing) are housed in eight buildings in the campus, including exact and natural sciences, as well as a part of social sciences and humanities. To this day, neither student dormitories nor accommodation for PhD students have been constructed (although they are likely to be built), which would emphasize the academic function of the campus. The campus also comprises areas with recreational, sports, residential and other service functions (e.g. catering, beauty, hairdressing, and commercial services), which are complemented by areas that serve transport functions. Location in the northern periphery of the city, and above all the railway line for freight (the northern bypass of Poznań) separating the city from the campus, makes transport to this part of the city limited. The results of the survey revealed a lack of a safe bicycle path between the western and eastern part of the campus, insufficient number of parking places for motorists, a lack of paved roads from the north and west, only three narrow access roads for car commuters, and difficult access by public transport to the eastern and north-eastern parts. In the latter case, the planned extension of the tram line towards Umultowo after the year 2022 is expected to solve the problem. Zarys treści: Celem opracowania jest charakterystyka najmłodszej przestrzeni Uniwersytetu im. Adama Mickiewicza – Kampusu Morasko. Opracowanie składa się z trzech zasadniczych części. Pierwsza część artykułu dotyczy genezy powstania i rozbudowy miasteczka uniwersyteckiego. W drugiej części przedstawiono strukturę przestrzenno-funkcjonalną kampusu w oparciu o inwentaryzację terenową, w trzeciej zaś obsługę transportową na podstawie badań ankietowych przeprowadzonych wśród studentów. Historia położonego w północnej, peryferyjnej części miasta kampusu rozpoczęła się od wmurowania aktu erekcyjnego i kamienia węgielnego w 1977 r. Dominująca do lat 80. XX w. funkcja rolnicza tego obszaru została zastąpiona przez nowe funkcje, głównie akademickie i naukowe. Pierwsze budynki dydaktyczne oddano do użytku dopiero w latach 90. ubiegłego wieku, a boom budowlany rozpoczął się po roku 2000. Swoją siedzibę znalazły tutaj nauki ścisłe i przyrodnicze, a także część nauk społecznych i humanistycznych, w sumie dziewięć wydziałów (na 21 istniejących) w ośmiu budynkach. Do dzisiaj nie wybudowano akademików czy domu doktoranta (choć istnieją realne szanse na ich powstanie), co podkreśliłoby funkcję akademicką kampusu. W strukturze kampusu wyróżnia się ponadto obszary o funkcjach rekreacyjnych, rekreacyjno-sportowych, mieszkaniowych i innych o charakterze usługowym (np. usługi gastronomiczne, kosmetyczne, fryzjerskie, handel), których uzupełnieniem są obszary o funkcjach komunikacyjnych. Położenie na północnych peryferiach miasta, a przede wszystkim linia kolejowa dla przewozów towarowych (północna obwodnica Poznania) oddzielająca miasto od kampusu sprawiają, że obsługa transportowa tej części miasta jest ograniczona. Wyniki badań ankietowych wskazują na brak bezpiecznej drogi rowerowej między zachodnią i północno-wschodnią częścią kampusu, niewystarczającą liczbę miejsc parkingowych dla zmotoryzowanych, brak utwardzonych dróg od strony północnej i zachodniej, zaledwie trzy wąskie wjazdy na kampus dla dojeżdżających samochodem czy utrudniony dojazd komunikacją publiczną do części wschodniej i północno-wschodniej. W tym ostatnim przypadku rozwiązaniem ma być planowana po 2022 r. rozbudowa linii tramwajowej w kierunku Umultowa.


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