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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Agricultural history and its effect on Lake Ekoln, central Sweden : A study based on historical maps and the use of sediment as a proxy for lake-water phosphorus

Avenius, Joel January 2015 (has links)
Agriculture and the use of arable land have long been assumed to be one of the key drivers behind eutrophication of lakes. However, little is known about how early agriculture has affected lakes in the past. The aims of this study were: i) quantify the within-region variability in historical land use and its linkage to soil cover and ii) test if the sediment geochemistry could be used to reconstruct inputs of phosphorus from early agricultural activities. The within-region variability was determined by digitalizing historical maps covering four centuries from the 18th to the 21st century for six selected regions across Sweden. To assess historical changes in lake-water phosphorus, a 6 m long 14C-dated sediment core from Ekoln was analyzed. The core was analyzed for 24 elements by X-ray fluorescence spectroscopy (XRF) together with the total concentration of nitrogen and carbon and their isotopes (δ13C, δ15N). Results show that there was a statistically significant difference (P<0.05) in agricultural activities between regions with soils rich in fine texture classes compared to soils with a more coarse texture. Agriculture also became less dependent on fine-grained soils due to new technological implements following the industrialization. The reconstructed long term-trend in Ekoln indicate limited inputs of phosphorus from early farming and that the lake had higher concentrations of phosphorus throughout the last millennia. Therefore, early farming was unlikely to be the prime driver of high phosphorus loadings, and that other factors should be considered, e.g. extensive urbanization and inputs of wastewater effluent.
2

Drained land and nutrient transport in the river Svärtaå catchment

Lannergård, Emma January 2011 (has links)
Land use changes such as lowering of lakes, draining of wetlands and channelizing of streams have affected the hydrological environment in many catchment areas. Numerous studies report that these changes affect the nutrient retention. The river Svärtaå catchment, near Nyköping is identified as one of the areas in Sweden that transport most phosphorus and nitrogen to the Baltic Sea per unit area. The aim of this study was therefore to analyse to which extent land use changes such as lowering of lakes, draining of wetlands and channelizing of streams have affected the nutrient transport to the Baltic Sea. Land use changes were to a large extent performed between the years 1880 and 1930 inSweden, historical maps from the late 19th century have therefore been studied. An application based on the concept of a Geographical Information System (GIS) has been used in order to compare the district map from late 19th century and the terrain map from today. To address the nutrient transport retention coefficients have been found in the literature and implemented on the changes in water area.  Changes in the hydrological environment reached totally1068 ha,964 hawere decreasing water areas and104 haincreasing water areas. Wet areas totally decreased with 28 % when the historical setting was compared with the contemporary environment. The loss in wet area represents860 ha. Watercourses with riparian zones have decreased with 54 %, bogs with 53 %, wetlands with 43 % and lakes with 13 %. The loss in retained mass regarding phosphorus was, based on calculations involving retention coefficients, 7,18 – 146 tonnes, and regarding nitrogen 37,9 – 941 tonnes. The changes in the catchment are probably connected to measures like lowering of lakes, draining of wetlands and channelizing of streams. The assumed lost retained masses shows to be high compared to the measured output from the catchment. This leads to questioning of the retention coefficients and the vast range between them, as well as questioning of other assumptions in the method. The consequences of the hydrological changes are therefore difficult to evaluate.
3

Reconstruction of Historic Maps of Central Mexico - S. XVI and XVII Using Geographic Infor- mation System (GIS) / Reconstrucción de mapas históricos del centro de México, siglos XVI y XVII, a través de un Sistema de Información Geográfica (SIG)

Arriaga Rivera, Armando 10 April 2018 (has links)
Most work on old maps has been to explain the forms of representation, its various uses and applications. At mid-twentieth and early twenty-first centuries it has developed historical cartography, means by which maps were made with old information or data mapping planes. In this paper the goal is to use the current mapping methods to reconstruct maps, based on the platform of geographic information systems (GIS); international conventional symbols; physical-geographical context ofthe time and current reference system for mapping and as a tool for spatial analysis. / La mayoría de los trabajos de cartografía antigua han sido sobre la explicación de las formas de representación, sus diversos usos y aplicaciones. A mediados del siglo XX y principios del XXI se ha desarrollado la cartografía histórica, medio por el cual se han realizado mapas con información antigua de datos o planos. En este trabajo el objetivo es emplear los métodos de representación cartográfica actuales, para reconstruir mapas, con base en las plataformas de los sistemas de información geográfica (SIG); la simbología convencional internacional; el contexto físico-geográfico de la época y un sistema de referencia actual, para generar cartografía y sea una herramienta para el análisis espacial.
4

Digitalizace historických map / Ancient Maps Digitizing

Pospíšil, Josef January 2008 (has links)
This work is about processing of historical maps, especially their digitizing and vectorization. The main focuses of this project are maps from the second historical military mapping and finding methods useful for removing texts from these maps.
5

Extraction de fragments forestiers et caractérisation de leurs évolutions spatio-temporelles pour évaluer l'effet de l'histoire sur la biodiversité : une approche multi-sources / Forest fragments extraction and characterization of their spatiotemporal evolution to evaluate the effects of history on biodiversity : a multi-source approach

Herrault, Pierre-Alexis 19 June 2015 (has links)
La biodiversité dans les paysages dépend des caractéristiques de ce paysage mais peut aussi être influencée par son histoire. En effet, certaines espèces ne réagissent pas immédiatement à une perturbation mais peuvent montrer un temps de réponse plus ou moins long. De ce fait, la prise en compte de l'évolution de l'habitat des espèces est devenue un enjeu important en écologie depuis quelques années, pour mieux comprendre la présence ou la diversité biologique actuelle. L'objectif de cette thèse en géomatique s'inscrit dans ce contexte applicatif d'écologie historique. Le sujet que nous traitons porte sur l'extraction automatique d'îlots boisés et la caractérisation de leur évolution spatio-temporelle depuis le milieu du XIXe siècle pour modéliser l'effet de leur trajectoire historique sur la diversité actuelle en syrphes forestiers (Diptera : Syrphidae). Le site d'étude est un paysage agri-forestier des Coteaux de Gascogne. La démarche générale proposée se compose de trois étapes principales : (1) la constitution de la base de données spatiales des îlots boisés intégrant plusieurs sources de données hétérogènes, (2) l'appariement des îlots boisés aux différentes dates avec la caractérisation de leur évolution spatio-temporelle, (3) la modélisation statistique des relations espèces-habitats intégrant l'histoire comme un des facteurs explicatifs de la diversité en syrphes observée. Plusieurs contributions méthodologiques ont été apportées à cette démarche. Nous avons proposé une nouvelle méthode de correction géométrique fondée sur la régression ridge à noyau pour rendre compatible les données spatiales anciennes et actuelles mobilisées. Nous avons également développé une approche et un outil de vectorisation automatique des forêts dans les dessins-minutes de la carte d'Etat-Major du XIXe siècle. Enfin, une première évaluation de l'impact de l'incertitude spatiale sur la réponse des modèles espèces-habitats a également été initiée. D'un point de vue écologique, les résultats ont révélé un effet significatif de la continuité temporelle des habitats sur la diversité en syrphes forestiers. Nous avons montré que les forêts les plus isolées présentaient une dette d'extinction ou un crédit de colonisation selon le type d'évolutions apparues au cours de la dernière période étudiée (1979-2010). Il s'est avéré qu'une durée de 30 ans n'était pas suffisante aux syrphes forestiers pour qu'ils retrouvent un été d'équilibre à la suite d'une évolution spatiale de leur habitat isolé. / Biodiversity in landscapes depends on landscape spatial patterns but can also be influenced by landscape history. Indeed, some species are likely to respond in the longer term to habitat disturbances. Therefore, in recent years, landscape dynamics have become a possible factor to explain current biodiversity. The aim of this thesis in GIS is part of this historical ecology context. We are dealing with automatic extraction of forest patches and characterization of their spatiotemporal evolution. The objective is to evaluate forest dynamics effects on current diversity of forest hoverflies. (Diptera: Syrphidae) in the agri-forestry landscape of Coteaux de Gascogne. The proposed general approach consists of three main steps: (1) the forest spatial database production from heterogeneous sources, (2) forest patches matching and characterization of their spatiotemporal evolution, (3) species-habitat modeling while integrating history as one of the factors likely to explain hoverflies diversity. Several methodological contributions were made. We proposed a new geometric correction approach based on kernel ridge regression to make consistent past and present selected data sources. We also developed an automatic extraction approach of forest from Historical Map of France of the 19th century. Finally, spatial uncertainty effects on ecological models responses have been assessed. From an ecological viewpoint, a significant effect from historical continuity of patches on forest hoverflies diversity was revealed. The most isolated fragments presented an extinction debt or a colonization credit according to area dynamics occurred in the last time-period (1970-2010). As it turns out, 30 years was not sufficient for forest hoverflies to reach new equilibrium after isolated habitat changes.
6

Ermittlung historischer Parameter eines kleinen Einzugsgebietes am Beispiel des Pfefferfließes / Detection of historical paramters of a small catchment area for the example Pfefferfließ

Schulze, Thomas January 2010 (has links)
Am Beispiel eines Fließgewässers (Pfefferfließ) wurde unter Verwendung verschiedener Methoden die hydrologische Situation eines naturnahen Zustandes des 18. Jh. dargestellt bzw. ermittelt. Die Grundlage zur Ermittlung eines naturnahen Zustandes des 18. Jh. waren historische Daten wie z.B. Karten, Handschriften, Meliorationspläne. Die Detektierung bzw. Aufnahme historischer Querschnitte sowie die Modellierung des Abflusses im 18 Jh. tragen ebenfalls zu einer Generierung des Gesamtbildes im 18.Jh. bei. Die aus diesen Daten gewonnenen Erkenntnisse wurden auf die weitere Anwendung als Leitbild für Renaturierungsmaßnahmen überprüft.
7

Skuggad terrängmodell och historiska kartor : Identifiering av forn- och kulturhistoriska lämningar i skogsmark / Shaded terrain models and historical maps : Identificetion of cultural heritage in forestland

Saur, Angelica January 2018 (has links)
Forestry has major negative effect with damage on cultural heritage in forest land. To avoid this, forestry needs to find new methods to search for and identify remains. In this study it was examined if shaded terrain models and historical maps could be used to identify ancient and cultural heritage in forest land. A field inventory was conducted to compare the cultural heritage objects identified in the digital maps with those found in the forest. The result showed that it is possible to identify ancient and cultural heritage using shaded terrain models and historical maps. 8 of the identified objects were also identified in field as real remnants. In historical maps, two remains were interpreted and identified, one of which was also identified in shaded terrain model. The conclusion was that shaded terrain model is an uncertain method to use, but together with other data it can be helpful to find cultural heritage. Forestry has major negative effect with damage on cultural heritage in forest land. To avoid this, forestry needs to find new methods to search for and identify remains. In this study it was examined if shaded terrain models and historical maps could be used to identify ancient and cultural heritage in forest land. A field inventory was conducted to compare the cultural heritage objects identified in the digital maps with those found in the forest. The result showed that it is possible to identify ancient and cultural heritage using shaded terrain models and historical maps. 8 of the identified objects were also identified in field as real remnants. In historical maps, two remains were interpreted and identified, one of which was also identified in shaded terrain model. The conclusion was that shaded terrain model is an uncertain method to use, but together with other data it can be helpful to find cultural heritage. / Forn- och kulturlämningar är historiska spår från våra förfäder och som till stor del återfinns i våra skogar. Skogsbrukets framfart har visat sig ha en stor negativ påverkan på lämningarna. SCA, Länsstyrelsen, Skogsstyrelsen och andra skogliga bolag har år 2020 satt upp en nollvision, inga forn- och kulturlämningar ska skadas. För att uppnå detta behöver skogsbruket hitta nya metoder för att söka ut och identifiera lämningar.   I denna studie utfördes en analys av skuggad terrängmodell och historiska kartor för att undersöka om det är möjligt att identifiera forn- och kulturlämningar i skogsmark. Efter analysen utfördes en fältinventering för att fastställa om de tolkade lämningarna var verkliga lämningar och vilka lämningstyper det i så fall var. Studien avgränsades till trakter i Västernorrland och till lämningstyperna; fångstgrop, kolbotten, tjärdal, röse, stenmur, stig och husgrund.   Resultatet visar att det är möjligt att identifiera forn- och kulturlämningar med hjälp av skuggad terrängmodell och historiska kartor. 8 av de tolkade lämningarna identifierades som verkliga lämningar. I historiska kartor tolkades och identifierades 2 lämningar, varav en även var identifierade i skuggad terrängmodell. Slutsatsen blev att enbart använda sig av skuggad terrängmodell för identifiering av forn- och kulturlämningar bedömdes vara en osäker metod i sig, men som komplement till andra data kan det vara en hjälp för att identifiera lämningar.
8

Vývoj využití území v oblasti centrální Šumavy v kontextu socio-politických změn / Development of land use in the central part of the Bohemian Forest in the context of socio-political changes

FLUKSOVÁ, Hana January 2011 (has links)
This thesis deals with the evaluation of land cover changes in twelve cadastral areas in the central part of the Bohemian Forest. This area was gradually abandoned due to political changes in the 20th century. For the purpose of this study, the historical Stabile Cadastre maps from 1837 and aerial photographs from 1949 and 2008 are used. The work follows both the development of the area as a whole and the development of the individual segments around the "Iron Curtain ", built after the World War II. Another aim of this work is to determine the spatial distribution of trees in an open countryside. Field data are supplemented with the features calculated from the digital elevation model and the distances of each species to man-made landscape elements present in the area around the time of displacement (aerial photos from 1949).
9

Erstellung einer interaktiven Kartenapplikation zur Ausstellung „Tabakstadt Dresden“ unter Verwendung historischer Karten

Figgemeier, Heiko 06 August 2021 (has links)
Diese Masterthesis behandelt den Entwicklungsprozess einer interaktiven Kartenapplikation, deren Bereitstellung und Nutzung als Teil einer Museumsausstellung im Stadtmuseum Dresden zum Thema Tabak erfolgt. Der Prozess beinhaltet die Aufbereitung und Geokodierung von historischen Standortdaten, die Georeferenzierung und das Kacheln einer historischen Hintergrundkarte sowie eine detaillierte Gegenüberstellung verschiedener Mapping-Bibliotheken. Als Kernbestandteil der Arbeit folgt schließlich die Beschreibung des Implementierungsprozesses mit Mapbox GL JS und aller wichtigen Bestandteile der Karte. Die gesamte Anwendung wird mit HTML, CSS und JavaScript entwickelt. Dabei wird aufgezeigt, welche Elemente für eine intuitive Bedienung der Benutzeroberfläche durch eine heterogene Personengruppe notwendig sind und wie sich eine Touch-Benutzeroberfläche von einer klassischen Desktopanwendung unterscheidet. Die Einschätzung der zumutbaren Interaktionstiefe ergab, dass das Interaktionslevel auf einem geringen Niveau gehalten werden muss, um eine einfache Bedienbarkeit zu ermöglichen. Die Applikation wurde nach der Entwicklung von einer kleinen Personengruppe evaluiert, wobei eine Beantwortung verschiedener Aufgaben mithilfe der Anwendung und eine Einstufung anhand ihrer Schwierigkeit erfolgte. Dabei ergab sich bei der Mehrheit der Aufgabestellungen eine fast ausschließlich problemlose Bedienbarkeit der Anwendung durch Nutzer aller Altersklassen mit Ausnahme der Altersklasse 70+. Die Evaluation zeigte jedoch Differenzen bei der Interaktion durch Menschen mit unterschiedlichem Vorwissen in Bezug auf interaktive Karten. Die Gegenüberstellung der JavaScript-Bibliotheken Leaflet, Mapbox GL JS und OpenLayers ergab projektbezogen für die Kriterien Visualisierung und Performance ein sehr gutes Abschneiden von Mapbox GL JS. Hier wird eine einfache Programmierung der Karteninhalte und eine ansprechende Darstellung der Kartenelemente ermöglicht.
10

En studie kring potentialen i svenska historiska kartor : Inför ett klimatanpassningsarbete samt en identifiering av historiska klimatrisker i syfte att bistå klimatutsatta fornlämningar

Romilsson, Simon January 2020 (has links)
Historical maps have been utilized diligently in various circumstances by archaeologists and antiquarians alike with the ambition to expose past landscapes and recreate features of the past. However, there is a shortage of information regarding the usage of historical maps relating to the climate change adaption. This study examines whether information about climate risks in Swedish historical maps can be revealed and subsequently used as an aid in climate change adaptation. To answer this question a literature review pertaining to historical maps, GIS-adaptations and current climate data was conducted in combination with a GIS-analysis integrating rectified historical maps and modern climate data. The results show that the maps exhibit some potential regarding the climate adaption mainly in relation to inundations and erosion. However, with future examination of the reliability of individual maps and vectorization in conjunction with added accessibility of map contents more valuable knowledge can be quantified and retrieved. / Historiska kartor har använts under olika omständigheter av arkeologer samt antikvarier i syfte att avslöja tidigare landskap och återskapa dåtida landskap. I detta sammanhang finns emellertid en brist på information om användningen av historiska kartor för klimatanpassningsarbetet. Denna studie avser att svara på om information om klimatrisker i svenska historiska kartor kan avslöjas och användas som ett hjälpmedel i klimatanpassningsarbetet med särskilt fokus på fornlämningar och övriga kulturhistoriska lämningar. För att besvara denna fråga genomfördes en litteraturöversikt avseende historiska kartor, GIS-anpassningar och aktuella klimatdata i kombination med en GIS-analys som integrerade rektifierade historiska kartor samt moderna klimatdata. Resultaten visar att kartorna uppvisar en viss potential när det gäller klimatanpassningen främst i förhållande till översvämningar och erosion. Med en framtida undersökning vad gäller tillförlitligheten av enskilda kartor samt en vektorisering och ökad tillgänglighet av kartornas innehåll kan en större mängd kvantifieras och upptäckas.

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