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Knowledge-based modelling of historical surfaces using lidar dataHöfler, Veit, Wessollek, Christine, Karrasch, Pierre 30 August 2019 (has links)
Currently in archaeological studies digital elevation models are mainly used especially in terms of shaded reliefs for the prospection of archaeological sites. Hesse (2010) provides a supporting software tool for the determination of local relief models during the prospection using LiDAR scans. Furthermore the search for relicts from WW2 is also in the focus of his research.¹ In James et al. (2006) the determined contour lines were used to reconstruct locations of archaeological artefacts such as buildings.² This study is much more and presents an innovative workflow of determining historical high resolution terrain surfaces using recent high resolution terrain models and sedimentological expert knowledge. Based on archaeological field studies (Franconian Saale near Bad Neustadt in Germany) the sedimentological analyses shows that archaeological interesting horizon and geomorphological expert knowledge in combination with particle size analyses (Köhn, DIN ISO 11277) are useful components for reconstructing surfaces of the early Middle Ages.³ Furthermore the paper traces how it is possible to use additional information (extracted from a recent digital terrain model) to support the process of determination historical surfaces. Conceptual this research is based on methodology of geomorphometry and geo-statistics. The basic idea is that the working procedure is based on the different input data. One aims at tracking the quantitative data and the other aims at processing the qualitative data. Thus, the first quantitative data were available for further processing, which were later processed with the qualitative data to convert them to historical heights. In the final stage of the work ow all gathered information are stored in a large data matrix for spatial interpolation using the geostatistical method of Kriging. Besides the historical surface, the algorithm also provides a first estimation of accuracy of the modelling. The presented workflow is characterized by a high exibility and the opportunity to include new available data in the process at any time.
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Mapping rill soil erosion in agricultural fields with UAV-borne remote sensing dataMalinowski, Radek, Heckrath, Goswin, Rybicki, Marcin, Eltner, Anette 27 February 2024 (has links)
Soil erosion by water is a main form of land degradation worldwide. The problem has been addressed, among others, in the United Nations Sustainability Goals. However, for mitigation of erosion consequences and adequate management of affected areas, reliable information on the magnitude and spatial patterns of erosion is needed. Although such need is often addressed by erosion modelling, precise erosion monitoring is necessary for the calibration and validation of erosion models and to study erosion patterns in landscapes. Conventional methods for quantification of rill erosion are based on labour-intensive field measurements. In contrast, remote sensing techniques promise fast, non-invasive, systematic and larger-scale surveying. Thus, the main objective of this study was to develop and evaluate automated and transferable methodologies for mapping the spatial extent of erosion rills from a single acquisition of remote sensing data. Data collected by an uncrewed aerial vehicle was used to deliver a highly detailed digital elevation model (DEM) of the analysed area. Rills were classified by two methods with different settings. One approach was based on a series of decision rules applied on DEM-derived geomorphological terrain attributes. The second approach utilized the random forest machine learning algorithm. The methods were tested on three agricultural fields representing different erosion patterns and vegetation covers. Our study showed that the proposed methods can ensure recognition of rills with accuracies between 80 and 90% depending on rill characteristics. In some cases, however, the methods were sensitive to very small rill incisions and to similar geometry of rills to other features. Additionally, their performance was influenced by the vegetation structure and cover. Besides these challenges, the introduced approach was capable of mapping rills fully automatically at the field scale and can, therefore, support a fast and flexible assessment of erosion magnitudes.
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Zur pedologischen Relativdatierung glazialgeomorphologischer Befunde aus dem Dhaulagiri- und Annapurna-Himalaja im Einzugsgebiet des Kali Gandaki (Zentral-Nepal) / Pedological relative dating of glaciogeomorphological features from the Dhaulagiri and Annapurna Himalaya along the catchment of the Kali Gandaki (central Nepal)Wagner, Markus 07 February 2007 (has links)
No description available.
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Paysages et évolution du haut-pays du plateau central marocain. Dynamique et propositions d'aménagementAherdan, Maya 19 March 1994 (has links) (PDF)
Le "plateau central" marocain, un ancien bloc appartenant à la base hercynienne atlasique, est constitué par quatre grands domaines morphologiques (la "up land", la Halow oriental, le milieu des terres et le "low land"). Le "up land", troisième niveau de cette unité géologique, est remarquable pour une structure appalachienne sur lequel se trouve par la discordance des motifs volcaniques datant de la fin du Tertiaire à l'époque Quaternaire. Trois de ces plus hauts plateaux qui forment cette unité font l'objet de cette recherche. Avec des altitudes similaires, ils présentent des paysages variés en raison de la différence lithologique. Par conséquent, la dynamique complexe récente diffère selon la région. En fait, le plateau Telt attire l'attention sur soi-même par son substratum essentiellement constitué par des flyschs. Lorsque la deuxième unité, le plateau Ment, se distingue par un complexe volcanique situé à l'Ouest et un grand batholite granitique. En ce qui concerne le plateau d'Oulmès, il est aussi constitué par un batholite granitique accompagné d'une auréole de métamorphisme. Placé au stade subhumide, les facteurs climatiques régionaux (de type méditerranéen) ont joué un rôle déterminant dans la distribution de la couverture végétale avec le chêne-liège en espèces essentielles. En raison de sa richesse lithologique et les facteurs climatiques, on observe une grande variété de sols. Il va sans dire que l'évolution de la dynamique récente et les paysages de la montagne sont également conditionnée par l'action anthropique, de plus en plus continue. Cinq parcelles, représentant les grandes régions morphologiques, sont sélectionnées afin d'appréhender les différents processus qui façonnent les formes variées et des paysages trouvés. Le but essentiel de cette recherche est constitué dans la définition des zones homogènes et de l'introduction de quelques suggestions au vu d'un ajustement. De cette façon, nous menons à une bonne intégration et à une harmonie entre les différentes unités présentées.
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Äolische Prozesse und Landschaftsformen im mittleren Baruther Urstromtal seit dem Hochglazial der WeichselkaltzeitBoer, Wierd Mathijs de 16 November 2012 (has links)
Das mittlere Baruther Urstromtal und Umgebung zwischen Luckenwalde und Golßen (Brandenburg, Deutschland) ist reich an äolischen Bildungen (DE BOER, 1990). Aus einer Kombination der bekannten Dünentypen (Parabel-, Längs-, Quer- und Kupstendünen) wird eine Reihe von 6 Dünenkomplexen abgeleitet. Sie sind aus einem oder mehreren Dünentypen aufgebaut und haben eine unterschiedliche Genese, Unterschiede im Alter und der Alterssfolge sowie eine bestimmte topographische Lage. Die (oberflächig anstehenden) Talsande/Flug(deck)sande, die Alt- und die Jungdünensande werden von Fein- bis Mittelsanden gebildet. In den jeweiligen Vertikalprofilen ist nach dem Körnungsbild eine Dreiteilung zu erkennen: die "liegenden" (Urstromtalterrassen-)Sande, die Altdünensande und die "hangenden" Jungdünensande. Das Liegende der ältesten Binnendünen ähnelt den Terrassensanden sehr. Daher darf angenommen werden, daß die oberen Urstromtalsande eine starke äolische Komponente besitzen. Altersbestimmungen wurden durch relative Positionierung, Feststellungen zur Art der Bodenbildungen, archäologische Funde, Pollenanalysen sowie Karten- und Literaturstudien vorgenommen, ergänzt durch Radiokarbon- (14C-) und Thermolumineszenzdatierungen. Eine methodische Neuerung ist die automatisierte Bearbeitung der Dünnschliffbilder. Mit dem Quantimet-970-Bildverarbeitungssystem wurde die Einregelung der Längsachsen von Quarzkörnern ermittelt. Die Messungen ergaben, dass die (N)NO-(S)SW-, die ONO-WSW- und die SSO-NNW-Richtungen vorherrschen. Es ist zu vermuten, dass die wichtigsten dünenbildenden Winde im Weichselspätglazial und im Holozän aus den westlichen und südlichen Quadranten wehten, wobei Südwestwinde vorgeherrscht haben dürften. Auf Grund der Forschungsergebnisse werden 12 Phasen der Dünenbildung unterschieden. Sie vermitteln ein Bild der äolischen Prozesse und Landschaftsformen, welches mit Daten aus Niedersachsen und West-Polen größtenteils übereinstimmt. / The Central Baruth Ice-Marginal Valley and surroundings between Luckenwalde and Golßen (Brandenburg, Germany) is rich in aeolian deposits and aeolian landscape forms DE BOER (1990). From a combination of the well-known dune forms (longitudinal, transverse, parabolic and hummocky dunes) a series of 6 dune complexes can be identified. These dune complexes are built by one or several dune types and differ in genesis or building sequence, in age or age sequence as well as in topographic position. The (surficial) valley/aeolian sands, the cover sands and the drift sands are mainly composed of fine- to medium-grained fractions. Based on grain-size analysis three units can be distinguished in the studied vertical profiles: the underlying (valley terrace) sands, the cover sands ("Altdünensande") and the overlying drift sands ("Jungdünensande"). The sands of the substratum of the oldest inland dunes are very similar to these dune sands. Therefore it is accepted that the upper parts of the valley sands contain a strong aeolian component. A modernization is the automated method of long axes orientation measurements on elongated quartz grains in thin sections with the Quantimet-970 Image Analyzer. The results showed that the (N)NE-(S)SW-, the ENE-WSW- and the SSE-NNW-directions dominated. It is to be expected that the most important dune building winds during the Weichselian Late Glacial and during the Holocene were winds from the western and southern quadrants, with southwest winds most likely being the most important. Dating was done by means of relative positioning, palaeosols, archaeological finds, pollen analysis, cartographic and literature research as well as by means of the 14C- and thermoluminescence dating methods. Based on the results of this research 12 dune-forming phases have been distinguished. They give an impression of aeolian processes and landscape forms that are in accordance with dates obtained from dunes in Niedersachsen and west Poland.
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