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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.
51

In Light of Energy: Influences of Light Pollution on Linked Stream-Riparian Invertebrate Communities

Meyer, Lars Alan 30 August 2012 (has links)
No description available.
52

DEVELOPMENTAL PLASTICITY OF STRESS TOLERANCE AND LIFE-HISTORY STRATEGY TO ARTIFICIAL LIGHT AT NIGHT

Bonfoey, Alyssa M. 01 January 2022 (has links)
Artificial light at night (ALAN), or ecological light pollution, is increasingly prevalent worldwide. Exposure to ALAN tends to negatively impact animals—particularly, nocturnal animals—but life-history strategies may mitigate these costs. Animals in many regions are also increasingly exposed to climate-related stressors, such as heat and drought. Yet, interactions among ALAN, life-history strategy, and stress tolerance are unknown. Therefore, I determined if developmental ALAN exposure (1) affects development, (2) affects adult phenotype, including heat and desiccation tolerance, and (3) affects and/or interacts with life-history strategy. To address my aims, I used the variable field cricket (Gryllus lineaticeps) because its geographic range is increasingly exposed to ALAN, heat, and drought conditions; it exhibits different life-history strategies (flight-capability vs. flight-incapability); and it is mainly nocturnal. Although developmental duration and success were not impacted by ALAN exposure, ALAN affected adult phenotype, with a positive effect on body mass, body size, and reproductive investment, and a negative effect on heat tolerance. Life-history strategy also affected stress tolerance—flight-incapable females had greater heat tolerance, and their desiccation tolerance was improved by ALAN exposure. Thus, key features of environmental change (i.e., exposure to ALAN, heat, and drought) may favor some life-history strategies over others.
53

The impacts of street lighting on bats

Day, Julie January 2017 (has links)
As human population grows and develops, more urban areas are expanding. Urbanisation has many impacts on the natural environment and one understudied pollutant is artificial light at night. The aims of this thesis were to examine the impacts of street lighting on bats and investigate the exposure of British bat species to artificial light at night and explored the mitigation option of part-night lighting. The current exposure of British bat species to artificial lighting was assessed using roost locations and population sizes from a long-term dataset (1997-2012) from the Bat Conservation Trust’s National Bat Monitoring Programme on seven bat species (Eptesicus serotinus, Myotis nattereri, Pipistrellus pipistrellus, P. pygmaeus, Plecotus auritus, Rhinolophus hipposideros and R. ferrumequinum). These data were combined with satellite imagery in roost sustenance zones and home ranges. Bat roosts were found in areas with brighter light levels than random locations for P. pipistrellus, P. pygmaeus and Plecotus auritus. Species that forage around streetlights (P. pipistrellus and P. pygmaeus) had significantly higher light levels in the landscape around their roosts than species which avoid street lit areas (R. hipposideros, M. nattereri and P. auritus). Colony size was negatively correlated with light levels. This study highlights that different species have different requirements in the landscapes around their roosts. To investigate landscapes effects of artificial light at night on the understudied light avoiding species R. ferrumequinum, eight maternity roosts were surveyed to explore the interaction between habitat features and street lighting. At each maternity roost, bat detectors were deployed at 25 paired street lit and dark locations. Street lighting had a significant negative effect on bat activity. Locations closest to the maternity roost had higher bat activity than those further away and road type had a significant effect on bat activity, with the highest bat activity recorded at minor roads compared with A and B roads. These results highlight the large negative impact street lighting can have on bat activity patterns and the need for mitigation. Several mitigation strategies have been suggested to combat the effects of artificial light at night but few have been tested. One of these suggestions is to restrict the hours of lighting through the night, often called part-night lighting. Part-night lighting has been implemented by many local authorities, often switching the lights off after midnight and switching them back on before dusk. To explore the effects of part night lighting on bats, the hourly patterns of activity for R. ferrumequinum were studied. Bat activity was bimodal, with a peak in the first few hours after sunset followed by a smaller peak before sunrise. To capture more than 50% of bat activity during the dark period of the night, street lights would be required to switch off before 11pm. To explore this further, a before-and-after study of part-night lighting was conducted at towns across Devon. Following the conversion from full-night lighting to part-night lighting, switching street lights off at 2 am, there was a significant reduction in P. pipistrellus and a significant increase for P. pygmaeus and Nyctalus noctule activity. Although part-night lighting is not often operational during peak activity periods for bat species, reducing the duration of lighting at night has impacts on activity patterns for several species. This thesis shows that artificial light at night has impacts on bats across the landscapes around their roosts. Artificial lighting has impacts for species in different ways, depending on whether they forage around street lights or avoid street lit areas. For species that avoid street lit areas such as R. ferrumequinum, street lighting can have very significant negative impacts on the availability of areas around their roosts. This highlights the need for conservation measures to reduce impacts of artificial lighting. Although mitigation schemes such as part-night lighting may help to minimize impacts of nighttime lighting, more tailored schemes for bats should devised to achieve greater conservation impacts.
54

People&amp / #8217 / s Experience Of Urban Lighting In Public Space

Unver, Ahmet 01 February 2009 (has links) (PDF)
This thesis aims to create new perspectives in urban lighting design by discovering people&amp / #8217 / s preferences in urban lighting through an exploratory research on people&amp / #8217 / s perceptive experience of urban space at night. In this study, I aim to analyze the common approaches and methods of urban lighting design and make their critique through my research results. Primary research objectives include the evaluation of what people perceive from the urban lighting design and how they feel about the design outcomes. In order to explore people&amp / #8217 / s experience of lit urban space at night, my research comprises a survey that aims to discover people&amp / #8217 / s opinions on certain lit urbanscenes collected from the city of Ankara. Urban lighting design is a discipline that emerged to improve the aesthetic quality of urban space. It has significant effects on people and consequently on urban life. However, in this discipline, exploration of people&amp / #8217 / s needs and preference is a neglected phenomenon. Therefore, this study suggests that it is necessary to review the designer-centered perspective on urban lighting design and question whether existing approach to this discipline has preferable outcomes for people. Through this research I aim to test whether it is appropriate to pursue and carry out the existing type of lighting design, and propose new perspectives to urban lighting.
55

Artificiellt ljus på natten : – en fenomenografisk studie om Sveriges kunskapsläge gällande ljusförorening som miljöproblem / Artificial light at night : – a phenomenographic study of Sweden’s state of knowledge regarding light pollution as an environmental problem

Ljungentorp, Robin January 2021 (has links)
Ljusförorening är ett miljöproblem vilket inbegripes som ett nytt och globalt framväxande fenomen i samband med himlaglim. Miljöproblemet i Sverige erkänns i viss mån med det nuvarande kunskapsläge. Dock saknas det en del kunskap för att komplettera ontologin för att bidra till ökad legitimitet för miljöproblemet bland allmänheten och Sveriges instanser. Studiens teoretiska analysramverket bestod av allmänningens tragedi, biogeoastronomiska natten och legitimitet, som användes till att analysera empirin härlett från studiens intervjumetod. Metoden hade en kvalitativ fenomenografisk ansats som innefattade ett strategiskt urval som var Sveriges instanser. Där uppdagades bristen på opinionsbildning i Riksdagen och Regeringen, trots att det finns motioner som har framlagts som vill att ljusförorening ska uppmärksammas, men att problemet hanteras snarare som en trafikfråga istället för miljöfråga. En del av förklaringen till varför det påverkar samverkan mellan Sveriges instanser för att motverka miljöproblemet. Ljusföroreningar påverkar ekologin och alla dess arter, varav krävs det tydligare riktlinjer för kommuner i deras belysningsplaner gällande att minska deras miljöpåverkan (särskilt för de nattaktiva arter som drabbas) för att nå målet till en mer hållbar belysning; varav ekologiska, ekonomiska och sociala aspekter vävs samman. Varav satsningar att bevara och etablera mörkerreservat är en pusselbit, vilket kan genomföras i samklang med Miljöbalkens författningar. / Light pollution is an environmental problem which is part of a new and globally emerging phenomenon in connection with skyglow. The environmental problem in Sweden is recognized to some extent with the current state of knowledge. However, there is also a lack of knowledge to complete the ontology in order to contribute to increased legitimacy for the environmental problem among the public and within its instances. The study's theoretical analytical framework consisted of the tragedy of the commons, biogeoastronomical night and legitimacy, which were used to analyze the empirical data derived from the study's interview method. The method had a qualitative phenomenographic approach that included a strategic selection of Sweden's instances. Where the lack of opinion formation was discovered in the Parliament and the Government, despite the fact that there is a proposition that has been presented that wants to light pollution to be noticed, but the problem is handled rather as a traffic issue instead of an environmental issue. Part of the explanation for why it affects the collaboration between Sweden's instances to counteract the environmental problem. Light pollution affects the ecology and all its species, which requires clearer guidelines for municipalities in their lighting plans regarding reducing their environmental impact (especially for the nocturnal species affected) in order to achieve the goal of more sustainable lighting; whereof which ecological, economic, and social aspects are woven together. In which investments to preserve and establish the dark sanctuary is a piece of the puzzle, which can be carried out in accordance with the Swedish Environmental Code constitutions.
56

Astro Tourism - A Possible Path to Sustainable Development through Narratives and Stories

Gerasimova, Darina January 2021 (has links)
This thesis focuses on the use of narratives and how they connect Astro tourism to sustainability. This research is done from the viewpoint of the narrators and uncovers what narratives they have chosen to present to the visitors, their reasons to include those narratives, what messages they want to convey and how that relates to sustainability. This research was conducted in order to explore how narratives can be used together with Astro tourism to sustainably develop peripheral regions. This thesis uses a qualitative approach with in-depth interviews and inquests. The informants are people who conduct narrated Astro tourism tours in different parts of the world. The findings of this thesis are that in Astro tourism narratives can be used to educate, inspire, shape perceptions, raise awareness and develop environmental consciousness in people. The narratives can take part in the place, value and identity creation processes, can provide a sustainable competitive advantage, can link together the visual aspects and reconnect the visitors to nature and the past. These findings can be used in the broader field of science about narratives and storytelling in the experience-based industry. On a more practical side it is recommended to include narratives that communicate ideas about sustainability that the narrators personally feel passionate about, and they should consider what kind of message they want to convey through them and how that will affect the customer’s experience.
57

Campus landscape

Dilts, Dustin 09 September 2013 (has links)
This body of work began as an exploration of the University of Manitoba’s Southwood Lands (a former eighteen-hole golf course), with the intention of proposing something new for the site. However, analysis and critical thinking led to the realization that there was a need to not only look at the Southwood Lands, but also the entire Fort Garry Campus. The work evolved through a process of discovery, using a variety of methods from walking the site, documentation through photography, visits to the archives to uncover history, and mapping from afar. One of the underlying objectives was to highlight the importance of taking additional time to understand a place prior to making decisions, revealing what makes a place unique, where the opportunities are, and what has been hidden over time. The idea of a site being a blank slate is dismissed, drawing on the importance of found conditions in decision making. Looking deeper into a place also leads to a greater respect for what is already there. It is what we already have that is so often discarded, and seen as having no value in decision making (the natural areas in a city or the trees on a former golf course for example). It is also the ecosystems that are seen as scrubby and unkept that are the most complex systems and richest spaces for life. Once complex, biologically rich systems are erased there is no going back to them. It is the existing conditions that are worth taking the extra time to investigate, a process that must occur prior to making design decisions that seek to remove or make new. It is only though looking, and looking carefully with un-objective eyes, and an open mind, that design can truly enhance what we already have. This practicum works under the premise that landscape has value in its own right. The landscape is not empty space, not just a place to put buildings, not a luxury that can easily be cut from budgets, and certainly not something that can be considered an afterthought. Instead, landscape is valued as something which is working and active, an essential part of life on this planet that is becoming increasingly important with a rapidly changing climate. The intellectual foundation for organizing ideas around approaching the site have been interpreted from Christophe Girot’s ‘Four Trace Concepts in Landscape Architecture’. They are in this order: landing, grounding, finding, and founding. While Girot’s four trace concepts organize ideas around approaching the site, there are three underlying principles that guide the entire body of work: 1. Landscape as infrastructure and organizing system; 2. Design as a process of discovery; 3. Investigation through multiple scales of inquiry. A strategy for the Fort Garry Campus is where this work concludes, followed by reflections on the importance of context in design and the lessons learned throughout the practicum process.
58

Campus landscape

Dilts, Dustin 09 September 2013 (has links)
This body of work began as an exploration of the University of Manitoba’s Southwood Lands (a former eighteen-hole golf course), with the intention of proposing something new for the site. However, analysis and critical thinking led to the realization that there was a need to not only look at the Southwood Lands, but also the entire Fort Garry Campus. The work evolved through a process of discovery, using a variety of methods from walking the site, documentation through photography, visits to the archives to uncover history, and mapping from afar. One of the underlying objectives was to highlight the importance of taking additional time to understand a place prior to making decisions, revealing what makes a place unique, where the opportunities are, and what has been hidden over time. The idea of a site being a blank slate is dismissed, drawing on the importance of found conditions in decision making. Looking deeper into a place also leads to a greater respect for what is already there. It is what we already have that is so often discarded, and seen as having no value in decision making (the natural areas in a city or the trees on a former golf course for example). It is also the ecosystems that are seen as scrubby and unkept that are the most complex systems and richest spaces for life. Once complex, biologically rich systems are erased there is no going back to them. It is the existing conditions that are worth taking the extra time to investigate, a process that must occur prior to making design decisions that seek to remove or make new. It is only though looking, and looking carefully with un-objective eyes, and an open mind, that design can truly enhance what we already have. This practicum works under the premise that landscape has value in its own right. The landscape is not empty space, not just a place to put buildings, not a luxury that can easily be cut from budgets, and certainly not something that can be considered an afterthought. Instead, landscape is valued as something which is working and active, an essential part of life on this planet that is becoming increasingly important with a rapidly changing climate. The intellectual foundation for organizing ideas around approaching the site have been interpreted from Christophe Girot’s ‘Four Trace Concepts in Landscape Architecture’. They are in this order: landing, grounding, finding, and founding. While Girot’s four trace concepts organize ideas around approaching the site, there are three underlying principles that guide the entire body of work: 1. Landscape as infrastructure and organizing system; 2. Design as a process of discovery; 3. Investigation through multiple scales of inquiry. A strategy for the Fort Garry Campus is where this work concludes, followed by reflections on the importance of context in design and the lessons learned throughout the practicum process.
59

Světový trh s osvětlovací technikou a pozice ČR na tomto trhu / Global lighting market and a position of the Czech Republic in this market

Šimetková, Tereza January 2015 (has links)
This thesis is focused on the analysis of the global lighting market and the assessment of the current position of the Czech Republic in this market. The first part is devoted to the theoretical introduction in the field of lighting technology. Furthermore, the thesis deals with the relation between lighting market and energy sector, especially with regard to energy efficiency policy. The market analysis is concentrated primarily on general lighting, which forms the largest and the most important lighting market segment. The development of the Czech lighting market is then discussed in the context of the global as well as the European market. Additionally, the thesis includes analysis of current trends in lighting technology and research conducted among manufacturers of lighting.
60

Stadsnära Norrskensturism : Viktiga parametrar gällande artificiell belysning för utvecklingen av norrskensturism i ett stadsnära läge / Northern Light tourism in an urban environment : Important aspects of the artificial lighting regarding the development of northern light tourism in an urban environment

Petersson, Rasmus, Tigerstrand, Rex January 2020 (has links)
Enligt Tillväxtverket (2019) har den totala konsumtionen inom svensk turismnäring ökat med 124% mellan åren 2000–2018. Denna trend kan även utläsas för den svenska naturturismen där en studie från Mittuniversitet (2014) visade att det inom naturturism omsätts ca 3.6 miljarder kronor varje år och att 40% av företagen var i en tillväxtfas (Fredman, Margaryan, 2014). En form av naturturism som växt sig stark norra Sverige under senare år är norrskenturismen (Jóhannesson & Lund, 2017; Mathisen, 2017; Friedman, 2010), som i enbart Kiruna kommun beräknas omsätta runt 100 miljoner varje år (Naturturismföretagen. 2019). Idag är denna typ av turism framförallt koncentrerad till landsbygden med långa avstånd och höga resekostnader som följd. Samtidigt som många turister har en negativ påverkan på djur och natur (Björnsdóttir, 2015). Syftet med studien är således att ta fram och föra en diskussion kring vilka aspekter av en belysningsanläggning som är viktiga för att göra norrskensturismen mer stadsnära och tillgänglig för en större del av befolkningen. Arbetet ska även ge förslag på generella anpassningar av den artificiella belysningen som kan appliceras på anläggningen. Metoden som används är en kombination av litteraturstudie, intervjuer och en analys av befintliga belysningsprogram. Litteraturstudien gav en bakgrundsundersökning inom ämnet samt tydliggjorde hur studiens syfte skulle formuleras. Intervjuerna genomfördes med fyra ljusdesigners där deras tankar och idéer gällande vilka aspekter som anses viktiga för att skapa en stadsnära norrskensturism. I studiens sista steg analyserades redan befintliga belysningsprogram från städer där belysningsanläggningen anpassats för att minimera stadens ljusföroreningar. Analyserna gav sedan konkreta åtgärdsförslag som jämfördes med intervjudeltagarnas resonemang. Studiens resultat visar på att armaturavskärmning, ljusfördelning, ljuspunktshöjder och belysningsstyrning anses vara de viktigaste aspekterna för den artificiella belysningen. Lagar, standarder och andra former av styrdokument är en annan aspekt som ofta togs upp, med resonemang för hur dessa kan påverka en belysningsanläggnings hösta respektive lägsta nivå. Gällande de generella förslagen på anpassningar redovisas att både anpassningar av ljuskällors färgtemperaturer och ljusriktning kan appliceras på en anläggning förhållandevis enkelt. Men att en väl anpassad belysningsstyrning är svårare, det ska dock tilläggas att denna anpassning kan ha större och mer positiv påverkan för en norrskensanpassad belysningsanläggning. Till de personer som vill utveckla denna typ av projekt rekommenderas att i ett tidigt skede blanda in eventuella intressenter och ta hänsyn till deras aspekter. Arbetets ämnesområde är relativt outforskat och en väl utförd förstudie inför projektet är därför av stor vikt för att minimera eventuella misstag. Studien begränsas av att enbart ta hänsyn till och föra en diskussion kring de aspekter som uppkommit under intervjuerna. Dessa aspekter är endast hämtade ur en ljusdesigners perspektiv och tydliggör således inte andra intressenters intressen inom ämnet. / According to The Swedish Agency for Economic and Regional Growth (2019) the total consumption of tourism in Sweden has grown with 124% between the years 2000-2018. This trend that also applies for the Swedish nature-tourism where a study from Mid Sweden University (2014) shows that nature-based tourism each year has approximately 3.6 billion SEK in turnover, and that 40% of concerned businesses is in a phase of growth (Fredman & Margaryan, 2014). Northern light-tourism is a form of nature-tourism that has grown quickly in northern Sweden in recent years (Jóhannesson & Lund, 2017; Mathisen, 2017; Friedman, 2010). In Kiruna alone it is estimated that the northern light tourism alone has a revenue of 100 million SEK each year (Swedish Nature and Ecotourism Association, 2019). This form of tourism often has a high traveling costs and is concentrated to the countryside with far traveling distances between each site. In the same time, a lot of tourists on the countryside has a negative impact on the nature and wildlife (Björnsdóttir, 2015). The purpose of this study is therefore to point out and discuss around different aspects concerning the artificial lighting with an impact on how we can develop a northern light- tourism in a more urban environment. The study shall also give general suggestions for how these aspects can be adapted into a light installation. The method that is use in this research is a literature study, interviews and an analyse of four cities’ lighting masterplans. The literature study was used to specify the foundation and aim of the study. Where the interviews clarified the important aspect for an urban development of northern light-tourism from a lighting designers’ point of view. In the last phase of the study, four lighting masterplans with a clear focus on how to prevent light pollution where analysed. These analyses then gave some action proposals that can be compared to the answers from the interview participants. The results from the study show that shielded luminaires, light distributions, luminaire installation height and lighting controls are considered to have the largest impact on the lighting installation regarding the visibility of the northern light. Also, laws and regulations were a common answer, with some reasoning about the regulations of max and min requirements from an installation. Regarding the general proposals some suggestions concerning luminaire colour temperature and light distribution can quite easy be applied to an installation, in comparison to a more complicated lighting control. To everyone that would like to develop a project of this kind it is recommended that in an early stage get in contact with any stakeholders and listen to their opinions. In that way any mistakes are minimised even though the topic of this study is relatively unexplored.The study is limited to only show and discuss the answers that came up under the interviews, and that these answers is only reproduced from a lighting designers’ point of view.

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