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Factors affecting piping plover (Charadrius melodus) nest site selection following landscape and predator community changesDorsey, Sharon Selena-Lee 18 January 2024 (has links)
The dynamics of coastal landscapes following major storm events and human interventions significantly impact nesting habitat use by species like the piping plover (Charadrius melodus) along Atlantic coastlines. Our study focused on Fire Island, New York, assessing changes in vegetation succession, plover nesting habitat selection, and suitable nesting habitat availability from 2010 until eight years after Hurricane Sandy. We analyzed classified imagery to quantify vegetative cover changes across the landscape and at nest sites. Results showed an increase of 11.5% change in vegetative cover across the study area, and nest sites experienced an increase in vegetation cover from 0.1% to 6.2% between 2015 and 2020. Selection for four habitat variables (i.e., distance to ocean, least-cost distance to bay, elevation, backshore width) was consistent throughout the study, but post-hurricane nests were situated farther from development and closer to bay areas (Euclidean distance) compared to pre-hurricane. Moreover, suitable nesting habitat peaked immediately post-stabilization but declined in subsequent years. Understanding these landscape shifts provides insights into species prioritization of habitat characteristics during nesting. Piping plovers face predation threats during breeding seasons while balancing consideration of the aforementioned habitat considerations, leading to specific nest placement strategies. Our study examined the relationship between nest site selection and the area visible from nests (viewshed) and evaluated its addition in nest site selection models including habitat variables. Piping plovers exhibited a preference for nest sites with increased predator visibility compared to random selection, indicating a strategic selection process. Initially influential (β = 0.43; CI = 0.28 – 0.58), the role of this predator visibility ('viewshed') diminished (β = -0.13; CI = -0.23– -0.04) as the landscape underwent ecological succession. Topographic variation caused greater visual obstruction at nest sites than vegetation. This study on piping plovers offers insights into the interaction between landscape changes, habitat selection, and predator visibility. The evolving importance of viewshed in nest site selection underscores the dynamic nature of nesting strategies in response to changing environments, and incorporation of this variable can improve the predictive ability of other models as it did for this study. These findings have broader implications for ground-nesting bird species and highlight the importance of considering landscape changes and predator visibility in land management strategies to safeguard vulnerable avian populations. / Master of Science / This is a study of piping plover (Charadrius melodus) nesting behaviors and nesting habitat conditions on Fire Island, New York prior to and following Hurricane Sandy in 2012. Over a decade, our observations documented remarkable alterations in both the landscape and nesting preferences of these birds. Vegetation that was initially covered by overwashed sand from the storm re-emerged in many areas across the study area and reduced the amount of suitable nesting habitat for plovers. Although some factors consistently influenced nesting site selection, after Hurricane Sandy, plovers nested farther from human development and closer to the coastal bay. Moreover, our investigation extended to understanding how these birds strategically choose safe nesting grounds with optimal visibility to potential predators. Initially, plovers nested in areas with greater visibility of predators, but as the landscape experienced vegetation succession nest-site viewshed became less of a priority. We also documented sources of visual obstruction at nests and determined that the topographic features obstructed more area than vegetation; however, sand captured by vegetation contributes to hummocks and dune creation. These findings illuminate the adaptability of piping plover nesting behaviors in response to the changing landscapes. Understanding how the environment changes and how animals adapt to these changes is crucial for creating strategies to protect vulnerable bird populations like piping plovers in coastal areas.
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Bortom graven : En rumslig studie av Tjustbygdens rösenSvenman, Emelie January 2014 (has links)
Bronze Age cairns have been interpreted as everything from navigation marks to marking liminal places in the landscape. It has also been stated that the main purpose of their location is to be visible. This is something that has been taken for granted. The main problem is the cairns have been considered as a homogenous monument. With the help of digital methods like GIS it is possible to test this kind of questions in quantitative way. The viewshed analysis is a good way to do this. The main focus of this thesis is the question whether the Bronze Age cairns in Tjustbygden, north-east in the county of Småland, are located to be visible in the landscape. Further, the question of whether the size of the monument has something to do with good visibility is dealt with. The result of the analysis is then discussed in relation to phenomenology and ritual phenomena, such as rock art sites.
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A Spatial Syntax for Perceived Safety in Urban Environments : for Application in Urban Planning / Geografisk analys av trygghet i urbana miljöer för tillämpning vid stadsplaneringOttenby, Nore January 2017 (has links)
Perceived safety is an important aspect of urban planning and is generally treated as an objective account of the personal sense of safety of each individual. The subject is inherently diffuse and therefore problematic to understand and evaluate in its entirety.This thesis builds on the practice of space syntax theory and the field of research that has sprung up around it, focused on quantifying urban qualities. A spatial syntax dedicated to perceived safety in urban environments is suggested, based on common themes in research and policy documents on the topic. Features that were considered to influence perceived safety were identified and their effects mapped with the use of standard GIS implementations. The effort aimed at introducing a quantitative approach to evaluation of perceived safety which is presently performed mainly in a qualitative manner. The features were quantified in the sense that their area of effect was mapped, which enabled measurements of the size and shape of their area of effect or number of features influencing a point in space. The mapped features have been listed below.• Field of view• Entrance locations• Active ground floors (e.g. storefronts and entrances available for public use)• Public lighting• Unclear landuseThe suggested methods were applied to the Stockholm suburb Skärholmen which currently suffers from lower perceived safety than the entire municipality and consists of an urban structure not considered to facilitate perceived safety by todays urban planning ideals.The methods were evaluated by reviewing the benefits of quantitative descriptions compared to written account, and through discussing the results with professionals at the planning office at the Municipality of Stockholm.The suggested syntax proved to have potential for concretizing the present planning process with respect to perceived safety. GIS is currently used in other aspects of urban planning and could be adapted to treat perceived safety. There would however be need for further standardization and a more user-friendly workflow. / Trygghet är en viktig aspekt inom stadsplanering och hanteras generellt som en objektiv beskrivning av enskilda upplevelser av trygghet i stadsbilden. Ämnet är diffust i sig självt och är därför problematiskt att till fullo förstå och utvärdera.Det här arbetet bygger på användandet av space syntax teori och den vetenskap som sprungit från ämnet, vilket syftar till att kvantifiera urbana kvalitéer. Ett spatialt syntax dedikerad till trygghet föreslås, som baseras på återkommande teman i forskning och plandokument som behandlar ämnet. Utformningar som anses påverka trygghet kartlades genom standardimplementering av GIS-verktyg. Syftet var att föreslå ett kvantitativt tillvägagångssätt för utvärdering av trygghet, vilket för närvarande generellt hanteras med kvalitativa men. De utformningar som kvantifierades gjordes så genom att det område de påverkar avbildades, vilket möjliggjorde fastställande av dessa områdens storlek och form samt hur många objekt som påverkar var punkt. De kartlagda utformningarna är listade nedan.• Öppet synfält• Entréplacering• Aktiva bottenvåningar (exempelvis skyltfönster samt entréer som inbjuder till publik användning)• Gatubelysning• Otydlig markanvändningDe föreslagna analysmetoderna applicerades på stockholmsförorten Skärholmen vilken för närvarande belastas av otrygghet jämfört men övriga kommunen och vars stadsutformning ger upphov till otrygghet enligt dagens stadsbyggnadsideal.Analysmetoderna utvärderades genom att bedöma fördelarna med resultaten jämfört med redogörelser i text samt genom diskussion med planerare på planorganet på Stockholms Stad.Det föreslagna spatiala syntaxet visade sig ha potential att konkretisera den aktuella planeringsprocessen med hänsyn till trygghet. GIS används vid behandling av andra frågor i stadsplanering och kan anpassas för att användas vid behandling av trygghet. Dock skulle viss standardisering samt ett mer användarvänligt utförande behövas.
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Montuhotep III and his role in the cultural landscape of ThebesSunneborn Gudnadottir, Anna January 2016 (has links)
This thesis concerns the cultural landscape in the Theban area during the Middle Kingdom, under the reign of Montuhotep III. What part he played in the connection of the Theban landscape was studied. The outlook point was the only temple that Montuhotep III founded in the Theban area, looking out over contemporary sites. The visibility in the Theban area during the early Middle Kingdom were studied by using Geographic Information System and interpreted by using phenome-nology. The viewshed analysis showed that three out of six contempo-rary sites were visible from Thoth Hill. This information was then used to interpret the choice of location.
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The castles of Mallorca : a diachronic perspective of the dynamics of territorial control on an Islamic islandGoffriller, Martin Sebastian January 2011 (has links)
This thesis pioneers a study in the dynamics of territorial control of the island of Mallorca from ca. 902-1300 AD, with the aim of providing the first holistic and systematic study of the known Islamic fortresses of this island, and determining the reasons which account for the lack of the so-called hisn/qarya complex there. The scientific focus of this project explores the effects that island contexts may have on the identity-forming processes of their population and how these in turn affect the socio-political makeup of these ‘bounded’ polities. More specifically, in the case of Mallorca the core of this study is devoted to the relation between the hinterland fortifications of the Islamic period and the island’s capital city Madīna Mayūrqa, concluding that due to the relative isolation of Mallorca’s segmentary communities from their mainland analogues they evolved a distinctive meta-identity which gradually supplanted their traditional tribal allegiances and redefined their relation with the state and political authority in general. Other areas of interest explored here are the use of rammed earth and masonry in Andalusi Architecture, and the mechanisms of integration of the Islamic territorial setup of Mallorca into the Christian kingdom of Aragon from 1229 onwards. The data here presented results from a broad variety of sources such as extensive archival research, architectural and spatial analysis of the 17+ sites surveyed, aerial photography, hydro-archaeology and in particular viewshed analysis, which was able to provide highly relevant results regarding the interconnectivity of the various sites and therefore give important evidence on their operational context. The creation of the viewsheds relied heavily on GIS software (Global Mapper 10-12) as well as architectural design software (AutoCAD, Illustrator, Sketchup) in order to carry out partial reconstructions of some of the main structures on the island.
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Evaluation du paysage et politiques publiques : application à l'agglomération de Montbéliard et à la commune de Morez (Franche-Comté) / Landscape assessment and publics policies : a case study of the urban area of Montbéliard and the municipality of Morez (Franche-Comté, France)Sauter, Alain 28 November 2011 (has links)
"Si le paysage s'est inséré dans l'action politique à toute les échelles, les effets de cette action devraient se faire sentir sur les paysages eux-mêmes. Il faut y voir de plus près." Cet objectif du programme de recherche "politiques publiques et paysages", lancé en 1998 par le Ministère de l'Aménagement, du Territoire et de l'Environnement, invite la communauté scientifique à investir le champ croisé de l'évaluation des paysages et des politiques publiques.Cette recherche doctorale apporte une nouvelle contribution à ce sujet, en reprenant les avancées acquises et les questions demeurées en suspens, et propose une mise en œuvre de l'évaluation par la production d'indicateurs du paysage, normés et comparables. La démarche suivie passe par la mise en place de mesures du paysage dans sa dimension visible, pour livrer aux acteurs publics de deux terrains d'étude franc-comtois une base de connaissance objectivée sur leur paysage. Ces mesures sont obtenues par des méthodes de modélisation de la visibilité, telles qu'elles sont proposées par les SIG, dans la ligne des travaux conduits par le laboratoire ThéMA pour l'approche quantitative et systématique du paysage visible (appliqués, par exemple, à l'étude du prix du paysage au cours de ces dernières années). Elles sont aussi développées de façon plus originale, en mobilisant des ressources en information géographique anciennes et actuelles disponibles pour les collectivités territoriales, avec leurs problèmes particuliers de mise en œuvre. Cette connaissance autorise alors une mise en regard du paysage et des enjeux soulevés par les politiques publiques, pour contribuer à leur évaluation mutuelle. / « If landscape is now part of public action at all scale levels, the effects of this action should be revealed in the landscape itself. We have to look further ». This main goal of the « public policies and landscape » research program, initiated in 1998 by the French ministry of environment, encourages the scientific community to invest both the landscape assessment and public policies research fields.This research aims at bringing a new contribution to this subject, taking into account recent advances and remaining questions. An assessment tool based on standardized and comparable landscape indices is proposed. This approach is based on measures performed on the visible part of the landscape, to deliver a quantitative knowledge to public stakeholders of two study fields in Franche-Comté (France). These measures are obtained through viewshed modelling, commonly implemented in GIS. They're also the result of original coding development using both old and recent geographic resources. This implementation task involved specific methodological issues. Thus, this knowledge allows us to confront landscape and stakes raised by public policies, in order to contribute to their mutual assessment.
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Förfädernas berg? : en tolkning av fornborgen på Halleberg / Mountain of the ancestors? : an interpretation of the hill-fort on HallebergTrollklint, Emil January 2011 (has links)
The essay deals with the hill-fort on the mountain Halleberg, Sweden, its wall design, functionality, dating and its possible function as a central location and a place of worship of the ancestors. The Halleberg hill-fort consists of a 1500 meters long at times cohesive stonewalls which together blocked the mountain from its surroundings. Hallberg's natural vertical scree and cliffs along with the masonry blocked the whole mountain from the surroundings. The hill-forts, with few exceptions are largely not investigated archaeologically and its functionality and role in the ancient society is based on outdated research on the subject. The current archaeological interpretation is that hill-forts served as temporary defense in times of unrest or served as center of power for a social elite. The prevailing view in the archaeological sphere is that the hill-forts had a variety of functions and that its functionality and role in ancient society has varied. Halleberg´s strongest wall sections are at the mountain's south-eastern part where the natural driveway, Storgårdsklev is located. Along with the massive masonry of the walls in Bokedalen Storgårdsklev functioned as the hill-forts main entrance. At places along the walls are the remains of what could be interpreted as stacked rocks and possible fire cracked stone. These structural features indicate that the walls were built during the early Iron Age. Very likely has its function like other hill-forts have been varied and changed based on the community, organization and internal and external disturbances. The essay's main interpretation is that the hill-fort served as a defensive fortress. Moreover it is possible that walls of the hill-fort had a symbolic role as a border between two separate rooms in the landscape. The fencing of Halleberg turned the whole mountain to a closed landscape, separated from the surroundings. It may have been a place where people worshiped their ancestors, a place where life's events, life and death was the focus point.
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Out of the Land of Forgetfulness: Archaeological Investigations at Bulow Plantation (8FL7), Flagler County, FloridaO'sullivan, Rebecca Claire 01 January 2012 (has links)
Developed in the early 1800's, Bulow Plantation is a prime example of the thriving sugar industry of East Florida prior to the Second Seminole War. Additionally, the layout of the slave cabins at Bulow Plantation in an arc centered on the main house is unique in Florida except for Kingsley Plantation near Jacksonville, FL. Despite its importance and the paucity of information available about even basic questions regarding life at Bulow Plantation, relatively little in the way of archaeological work has been done at the site. Using historical research and non-destructive archaeological techniques such as pedestrian survey, aerial LiDAR (Light Detection and Ranging), and remote sensing completed as part of recent work by the Alliance for Integrated Spatial Technologies (AIST) (Collins and Doering 2009a; Collins et al 2010) this work examines not only the material landscape of Bulow Plantation but also the social and cognitive landscapes that might have shaped life for both enslaver and enslaved. Using data collected as part of AIST's larger project (Collins et al 2010) an analysis of the pedestrian survey data, as well as a Digital Elevation Model (DEM) created from aerial LiDAR data, revealed the locations of several previously unrecorded slave cabins as well as some large scale landscape features. Although there are three competing theories as to why the Bulow slave cabins were arranged in an arc, without subsurface archaeology it is impossible to endorse one interpretation over another. While the analysis of landscapes generally privileges the view of those in power, suggestions for future archaeological work are made so that the voices of those who were enslaved at Bulow Plantation can begin to be heard.
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Panoraminio vaizdo tyrimo metodika ir taikymas (ArcGIS programinio paketo pagrindu) / Methodology of investigation and application of viewshed (using program package of arcgis)Motiejūnas, Giedrius 09 July 2011 (has links)
Šiame darbe nagrinėjama panoraminio vaizdo tyrimo metodikos ir taikymo problematika. Aptariami pagrindiniai algoritmai naudojami ArcGIS programoje. Darbe pateikiama keletas pavyzdžių, kaip panoraminio vaizdo tyrimai taikant GIS programinę įrangą yra pritaikomi praktikoje. Antroje darbo dalyje yra atliekamas tyrimas, kurio tikslas išsiaiškinti, ar racionalu ir reikalinga būtų taikyti panoraminio matomumo tyrimus žemėlapyje, nekilnojamo turto reklama užsiimančiuose interneto puslapiuose. Tyrimo rezultatai atskleidžia, kad vietovės vaizdingumas yra svarbus veiksnys renkantis nekilnojamą turtą, o žmonės yra pasiruošę naudotis naujomis žemėlapio funkcijomis suteikiančiomis daugiau galimybių atliekant nekilnojamo turto vertinimą, tačiau panoraminio matomumo įrankio diegti į sistemas nerekomenduojama, dėl darbe aptariamų šios funkcijos trūkumų. Kita vertus autorius siūlo diegti naujas funkcijas, kurios pagerintų nešališką nekilnojamo turto vertinimą. / Work is developing the problem of methodology and applications of viewshed. Author is writing about main algorithms of this GIS function in ArcGIS program. Few practicable applications of viewshed are presented at work also. Item, some problems of these algorithms and applications of viewshed are developing. In second part of work author presents research about applications of viewshed for the internet web sites where is presented commercial of realty. The result consequent upon the research said that visibility is one of the main criterions of realty. Also Purchasers are ready for innovations of geographical information systems. On the other hands realty needs new GIS and mapping applications. In the conclusion of work author says that it is not worth to add the tool if viewshed to GIS systems to web pages of commercial of realty, because this tool have some problems for applications. On the other hand author suggests add some other functions to these maps which will improve neutral evaluation of realty.
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Böten, Signalen och Branden : Att undersöka förutsättningarna för signalsystem med hjälp av GIS och ortnamn / The Beacon, the Signal and the Fire : To explore the conditions of signal systems using GIS and placenamesPalmborn, Markus January 2018 (has links)
Scandinavia is famous for their Viking ships and their raids during the 9th century. However, the Scandinavian society was widely divided between the ruling forces. There are a lot of evidence for conflicts within the Viking world, with both written sources, stories and archaeological records speaking for it. As the ship, and travel by water, was one of the most efficient ways of travelling, widely used within all of Iron Age Scandinavia, this paper seeks to explore the possibilities of a maritime defense system within the central Viking society using place names and GIS. Uppland, as one of the most influential areas in Scandinavian Iron Age, hosting sites as Vendel and Gamla Uppsala, the use and need of a maritime defense would have been, due to the risk of conflict, vital.
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