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Abundant wood remains and buried trees have been found in the western part of Lithuania near Zakeli?kiai and Lyduv?nai on Dubysa River (a tributary of Nemunas River) where deposits are rich in organic remnants and buried soils. In Zakeli?kiai and Skiru?iai sections of Dubysa River oxbow sediments were investigated by various methods (dendrochronological, carbonate, granulometric, pollen and mollusc fauna analysis). In addition, these sections were dated using the radiocarbon method. Samples were collected from deposits of Dubysa River outcrops. The studied oxbow lakes have existed for more than 5 thousand years (from ca. 4300 BC to 1000 AD). During this period organic rich deposits with trees and branches were formed in the oxbow lake. This indicates that at the end of Atlantic, during Subboreal and in the early Subatlantic periods there was a forest growing that contained mainly oaks which were falling down into an oxbow lake and later were covered by sandy and silty deposits. The granulometry of alluvial deposits, as well as the mixture of medium-grained sand and silt show different stages of Dubysa River palaeochannel formation: riverbed and oxbow lakes. Three climate warming cycles were revealed according to carbonate analysis data in all investigated sections. The rheophile thermophilous Holocene age molluscs species Bithynia tentaculata L., Unio cf. crassus Philipsson, Pisidium amnicum (Müller), Theodoxus fluviatilis (Linnaeus) have been found. The pollen composition and sequences have been divided into five local pollen assemblage zones (LPAZ) and described according to pollen spectra in each zone. In this way it is possible restore palaeoclimatic coherent evolution, trends and cyclical change.  相似文献   
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Deutschland hat ein umfassendes und in der Praxis bew?hrtes Planungssystem einschlie?lich integrierter Umweltprüfung, das auch für zus?tzliche bzw. erweiterte Prüfinstrumente günstige Voraussetzungen bietet. Das Fl?chenmonitoring in der Regionalplanung, aber auch für die St?dte und Gemeinden in der vorbereitenden Bauleitplanung kann mit Hilfe einer gezielten Ver?nderungsanalyse der Landbedeckung als ein Baustein eines umfassenden Monitoringsystems und zur Unterstützung des Nachhaltigkeitsprinzips verstanden werden. Da jedoch insbesondere für einen l?ngeren Beobachtungszeitraum kaum bzw. keine (digitalen) Informationen über die Landbedeckung existieren, stellt die Auswertung von Satellitendaten einen L?sungsansatz dar. Inwiefern sich die semiautomatische Analyse von Satellitenbildern als ein geeignetes Instrument zur Bewertung und Ver?nderung der Nutzung eines Landkreises eignet bzw. worin Analyseprobleme sowie M?glichkeiten und Grenzen der Anwendung in der Regionalplanung existieren, soll im folgenden Beitrag am Beispiel des Landkreises Osnabrück thematisiert werden.  相似文献   
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Thanks to advances in technology such as Internet-based mapping and the development of special inks, papers and global positioning systems, map making for vision impaired people can provide a range of products (e.g., tactile, haptic and audio-tactile maps) that can improve their independence, self-confidence and everyday life. The applications of tactile maps include learning spatial concepts and geography; audio-tactile maps combined with access to geospatial information can enhance mobility and independence. In 1998, the Mapping Services Branch (MSB) of the Earth Sciences Sector of Natural Resources Canada initiated a tactile mapping program. Now referred to as the Government on Line—Mapping for the Visually Impaired Project (Natural Resources Canada 2003a), it aims to serve the community with special needs, with emphasis on those who are blind or visually impaired, their teachers and mobility instructors. This technical paper discusses the various types of tactile and audio-tactile maps of Canada developed by the MSB in cooperation with its partners and describe the current research and development activities carried out within the project. It also leads the reader to further information on audio-tactile maps and touch- and sound-based computer interfaces.  相似文献   
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The Charles Bridge is the oldest, still-standing gothic bridge that crosses the Vltava River in Prague and up to now has belonged among the most sought-after historical monuments in the Czech Republic. The bridge has been repeatedly damaged due to floods and has been repaired several times. In the reconstructions, damaged sandstone blocks were substituted in facing. This experimental study focused on nonlinear ultrasonic spectroscopy for testing stone blocks that were extracted from the historical bridge structure. The objective of these experiments was verifying whether the methods can be applied to evaluating the internal structure of blocks, which are built-in in the structure in situ. Intact-structure blocks, blocks that had been repaired in the past, and damaged-structure blocks were measured. Two methods of nonlinear ultrasonic spectroscopy were applied—the method with single harmonic ultrasonic signal and with two harmonic ultrasonic signals. Measurement results of both applied methods proved resulting parameters correlation with block structure integrity quality.  相似文献   
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