Järnvägen är en förutsättning för att hantera klimatkrisen och sträva mot ökad hållbarhet då utsläppen från järnvägstransporter är låg i relation till andra transportslag. Trafikverket ska bidra till det genom att arbeta för att järnvägen har en säkerhetsnivå som är ekonomiskthållbar för samhället. Det innebär att resenärer och godstransportörer ska välja järnvägframför andra transportslag genom att det skapas rätt balans mellan säkerhet, punktlighet och kostnad. För att uppnå det arbetar aktörer inom järnvägen integrerat med driftsäkerhet ochsäkerhet. För att i ökad omfattning även beakta hållbarhet ur ett miljöperspektiv är cirkulariteten väg framåt. Spårväxlar är en kritisk del i järnvägsinfrastrukturen då de har en viktig funktion samtidigt som de är säkerhetskritiska, dyra att installera och underhålla samt ligger i topp när det gäller trafikstörningar. För att hushålla med statens resurser tillämpar Trafikverket byte av komponenter i spårväxlar för att förlänga tiden mellan byte av hela spårväxlar. För att hushålla bättre med resurserna och samtidigt öka hållbarheten är det intressant att återanvända utbytta spårväxelkomponenter istället för att endast återvinna deras material. Nuvarande arbetssätt saknar dock systematisk återanvändning av annat än bristkomponenter, vilket kräver utveckling.Syftet med detta examensarbete är att utforska en cirkulär modell för hantering avåteranvända komponenter inom järnvägsunderhåll. Genom driftsäkerhetsanalyser identifieras kritiska spårväxelkomponenter för att utforma ett effektivt och ändamålsenligt underhåll för ökad cirklaritet. Arbetet fokuserar på att identifiera kritiska komponenter och geografiska platser i anläggningen samt undersöka arbetssätt för återanvändning av spårväxlar och dess komponenter för ökad cirkularitet. Frågeställningen är ”Hur kan en cirkulär modell utformas och tillämpas för att effektivt återanvända spårväxlar och dess komponenter inom järnvägsunderhåll?”Arbetet är en kombinerad litteratur- och fallstudie med en abduktiv ansats. Fallstudien omfattar Trafikverket samt spårväxlar på Malmbanan och Haparandabanan. Kvalitativa data har samlats in via, intervjuer och dokumentstudier. Kvantitativa data har samlats in via databasstudier. Kvalitativa data har analyserats utifrån material från litteraturstudien samt tematisk analys, medan driftsäkerhetsanalys i Excel och Minitab har tillämpats förkvantitativa data. Resultatet visar att utifrån antal fel och trafikstörningar är växeltungor och korsningar de mest kritiska spårväxelkomponenterna. Det finns dock även andra kritiska komponenter beroende på bandel, besiktningsklass och årstid. Sverige har tidigare haft växelrevisionsverkstäder där komponenter återanvändes, vilket fortfarande praktiseras i Storbritannien. Järnvägsanläggningen inspekteras före ombyggnadsprojekt och spårväxlar transporteras till centrallager för vidare inspektion av komponenter. Spårväxelkomponenter är eftertraktade och återanvänds vid komponentbyten i anläggningen, men även hela renoverades pårväxlar. En gemensam framgångsfaktor för ökad cirkularitet anges vara ansvarstagande,effektiv lagerhantering, god kommunikation mellan aktörerna i processen samt hög kompetens. / The railway system is essential for addressing the climate crisis and promoting sustainability,as railway emissions are relatively low compared to other modes of transport. Trafikverket,the Swedish Transport Administration, aims to ensure that the railway maintains a safety level that is economically sustainable for society, encouraging passengers and freight carriers tochoose rail by balancing safety, punctuality, and cost. Stakeholders in the railway sector work integratively with operational reliability and safety, and circularity is a viable path forward for environmental sustainability.Railway switches are a critical part of the infrastructure due to their important function,safety-critical nature, high costs, and their leading role in causing traffic disruptions.Trafikverket replaces components in railway switches to extend the intervals between complete replacements. To further improve resource efficiency and sustainability, reusing replaced switch components is beneficial. However, the current practice lacks systematic reuse beyond shortage components.This thesis explores a circular model for handling reused components within railway maintenance. Through dependability analyses, critical switch components are identified to design an effective maintenance strategy that enhances circularity. The work focuses on identifying critical components and geographic locations within the infrastructure and examining methods for reusing switches and their components. The research question is:"How can a circular model be designed and applied to effectively reuse switches and their components within railway maintenance?" This study employs a combined literature review and case study with an abductive approach.The case study encompasses Trafikverket and the railway switches on Malmbanan and Haparandabanan. Qualitative data was collected through interviews and document studies,while quantitative data was gathered through database studies. The qualitative data was analyzed using materials from the literature review and thematic analysis, while quantitative data was analyzed using dependability analysis in Excel and Minitab.The results indicate that, based on the number of faults and traffic disruptions, switch rails andcrossings are the most critical components. Other critical components were identified depending on the specific track section, inspection class, and season. Sweden previously had switch revision workshops where components were reused, a practice still employed in theUK. Key success factors for increasing circularity include accountability, efficient inventory management, good communication between stakeholders, and high competence.

Master of Science / Department of Biology / Craig Paukert / Improperly designed stream crossings may prohibit movement of stream fishes by creating physical or behavioral barriers and may alter the form and function of stream ecosystems. A mark-recapture and geomorphological study was conducted to evaluate fish passage and stream morphology at three types of vehicle crossings (compared to control sites) located on streams in the Flint Hills of Northeast Kansas. We investigated five concrete box culverts, five low-water crossings (concrete slabs vented by one or multiple culverts), and two single corrugated culverts. A total of 6,433 fish were marked April to May 2007 and 709 were recaptured June to August 2007. Fish passage occurred at all crossing types, but upstream movement of recaptured fish was higher at controls (41.1%) than at crossing reaches (19.1%) for low-water crossings. Control sites had more species in common upstream and downstream than did crossings. There was reduced overall abundance of fish upstream at low-water crossings, commonly percids and centrarchids. A comparison of channel and road crossing dimensions showed that box culverts and corrugated culverts would be more effective than low-water crossings at transporting water, sediments, and debris during bankfull flows, and fish passage at base flows. Upstream passage of Topeka shiner (Notropis topeka), green sunfish (Lepomis cyanellus), red shiner (Cyprinella lutrensis), and Southern redbelly dace (Phoxinus erythrogaster) was tested through three simulated crossing designs (box culverts, round corrugated culverts, and natural rock) across 11 different water velocities (0.1 m/s to 1.1 m/s) in an experimental stream. Upstream movement did not differ among designs, except natural rock crossings had lower movement than box or corrugated culverts for red shiners. A greater proportion of Topeka shiners moved upstream at higher velocities. These results suggest that crossing type affects fish passage and the morphology of the stream, although water velocity in different crossing designs alone may not be a determining factor in fish passage. Low-water crossings had the greatest impact on fish community and movement, but barriers to fish movement are likely caused by other variables (e.g. perching). Use of properly designed crossing structures has great promise in conserving critical stream habitat and preserving native fish communities.

Thesis (MScEng)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Road traffic accidents have been a global concern facing all countries. Approximately 1.2 million people are killed annually as a result of traffic accidents and 50 million are injured. More than 90 percent of road fatalities occur in the developing world which has only 48 percent of the world’s registered vehicles. Beyond the problem of road fatalities, road traffic accidents result in disability and long term injury. They also cause considerable economic losses to victims and their families and damage properties and infrastructures. In South Africa, pedestrian fatalities account for about 40 percent of all road traffic accidents. Behaviour patterns of both pedestrians and motorists at pedestrian crossings are the main influential factors of pedestrian accidents. This study investigates behaviour patterns of pedestrians negotiating different types of crossing facilities in the town of Stellenbosch, in South Africa. A total number of 17 pedestrian crossings were selected for the study on the basis of their geometric and operational characteristics. Video-based observations together with on-street interviews were used to understand crossing behaviour patterns, namely pedestrian walking speed, pedestrian delay, gaze behaviour, pedestrian-vehicle conflicts, pedestrian compliance with road traffic rules and gap-acceptance behaviour. Results of the study showed that male pedestrians walk more than female pedestrians. The 15th percentile crossing speed for all pedestrians observed while crossing was found to be 1.13 m/s whereas the mean crossing speed was found to be 1.48 m/s. Demographic variables appeared to significantly influence pedestrian walking speed. Male and younger pedestrians exhibited higher walking speeds than female and older pedestrians. Pedestrian walking speed was also found to be affected by group size, encumbrance, type of pedestrian facility and distraction while walking. However, no effects of conflicts and the presence of a pedestrian refuge on pedestrian walking speed were found in this study. A mean total delay of 5.10 seconds was found in this study. Male and younger pedestrians experienced shorter delay compared to female and older pedestrians. The type of pedestrian facility and traffic signals during which pedestrians arrived at the kerb and crossed appeared to be other influential factors of pedestrian delay. With regard to gaze behaviour, an average number of head movements ranged from 2 to 5 at the kerb and from 3 to 5 while crossing. Conflicts with motorists peaked where crossing distances were longer and traffic volume was heavy. A red light violation ranging from 82 to 87 percent was observed in this study and on-street surveys indicated that beliefs and attitudes towards traffic control devices and traffic environment significantly explained pedestrians’ unsafe crossing behaviour. The calculated critical gap and critical lag ranged from 2.19 to 3.90 seconds and the effect of crossing distance on gap-acceptance emerged in this study. Possible interventions are finally suggested. / AFRIKAANSE OPSOMMING: Padongelukke is 'n wêreldwye probleem wat al die lande in die gesig staar. Ongeveer 1,2 miljoen mense sterf jaarliks as 'n gevolg van verkeersongelukke en 50 miljoen word beseer. Meer as 90 persent van padsterftes kom voor in die ontwikkelende wêreld met slegs 48 persent van die wêreld se geregistreerde voertuie. Bo en behalwe die probleem van padsterftes, het padongelukke gestremdheid en lang termyn beserings tot gevolg. Dit veroorsaak ook aansienlike ekonomiese verliese vir die slagoffers en hul gesinne en skade aan eiendomme en infrastruktuur. In Suid-Afrika is voetgangersterftes verantwoordelik vir sowat 40% van alle padongelukke. Gedragspatrone van beide voetgangers en motoriste by voetoorgange is die belangrikste bepalende faktore van voetganger-ongelukke. Hierdie studie ondersoek gedragspatrone van voetgangers by verskillende tipes kruisings in die dorp van Stellenbosch Suid-Afrika. ʼn Totale aantal van 17 voetoorgange is gekies vir die studie op die basis van hul geometriese en operasionele eienskappe. Video-gebaseerde waarnemings saam met op-straat onderhoude is gebruik om kruising-gedragspatrone, naamlik voetganger stapspoed, voetganger vertraging, kyk gedrag, voetganger-voertuig konflikte, voetganger nakoming van padverkeersreëls en gaping-aanvaarding gedrag te verstaan. Resultate van die studie het getoon dat manlike voetgangers vinniger loop as vroulike voetgangers. Die 15de persentiel kruising spoed vir alle voetgangers waargeneem binne kruisings was 1,13 m/s, terwyl die gemiddelde kruising spoed 1,48 m/s is. Demografiese veranderlikes beïnvloed voetgangers loop-spoed. Manlik en jonger voetgangers loop vinniger as vroulike en ouer voetgangers. Voetgangers loop-spoed word ook geraak deur die grootte van die groep, die dra van items, die tipe voetganger-fasiliteit en afleiding terwyl geloop word. Daar is egter geen gevolge van konflikte op voetgangers loop-spoed in hierdie studie gevind nie. 'n Gemiddelde totale vertraging van 5,10 sekondes is in hierdie studie gevind. Manlik en jonger voetgangers ervaar korter vertraging in vergelyking met die vroulike en ouer voetgangers. Die tipe voetgangerfasiliteit en verkeerseine was ander invloedryke faktore van voetganger vertraging. Vir waarneming van die verkeer is gevind dat die gemiddelde aantal kopbewegings gewissel het van 2 tot 5 teen die randsteen en van 3 tot 5, tydens die kruising. Konflikte met motoriste het ʼn hoogtepunt bereik waar kruising afstande langer en verkeersvolume hoër was. Rooi lig oortredings wat wissel van 82 tot 87 persent is in hierdie studie waargeneem en op-straat opnames het aangedui dat houdings teenoor verkeer-beheer toestelle en die verkeersomgewing die voetgangers se onveilige kruising-gedrag verduidelik. Die berekende kritiese gaping het gewissel van 2,19 tot 3,90 sekondes en die effek van die kruisinglengte op gaping-aanvaarding het in hierdie studie na vore gekom. Moontlike intervensies word voorgestel.

<p>Istraživanje koje je sprovedeno u okviru disertacije poslužilo je za definisanje matematičkog modela koji se može primeniti u postupku određivanja nivoa usluge za nesignalisane pešačke prelaze. Formirani model za proračun stepena propuštanja pešaka u uslovima lokalnog odvijanja saobraćaja zavisi od protoka pešaka i vozila, strukture saobraćajnog toka (učešće autobusa i teretnih vozila) i smera kretanja vozila na lokaciji pešačkog prelaza. U okviru disertacije izvršena je analiza pešačkih intervala prilikom prelaska kolovoza. Uporednom analizom prihvatljivih i kritičnih intervala dobijen je model ponašanja pešaka u zavisnosti od karakteristika lokacije nesignalisanog pešačkog prelaza. Utvrđena je zavisnost između dužine prihvaćenih intervala pešaka prilikom prelaska kolovoza i uslova odvijanja saobraćaja, polnih karakteristika pešaka i broja pešaka koji prelaze kolovoz na nesignalisanom pešačkom prelazu.</p> / <p>The study, which was conducted within the thesis, has served to define a mathematical model that can be applied in the process of determining the level of service at unsignalized pedestrian crossings. The formed model for motorist yield rate, in terms of the local pedestrian traffic flow, depends on pedestrian and vehicular flow rate, traffic flow structure (the share of buses and freight vehicles), and vehicle moving at the location of a pedestrian crossing. The pedestrian gap acceptance behaviour has also been analysed. Comparative analysis of acceptable and critical pedestrian gap was conducted. Model of pedestrian behaviour, which depending on the site characteristics, was formed and it has been proven a correlation between the length of the accepted pedestrian gaps and the roadway and traffic conditions, gender characteristics and the number of pedestrians at unsignalized crossings.</p>

Made available in DSpace on 2017-07-10T17:31:24Z (GMT). No. of bitstreams: 1 Leandro_Neri_Bortoluzzi.pdf: 4120006 bytes, checksum: e870dd7340723061217fb4d7fdece089 (MD5) Previous issue date: 2012-05-03 / The bridges and culverts alter the natural conditions of rivers, causing changes in fluvial processes. The level of stability of river banks and beds around crossing structures was evaluated in the Paraná III watershed, Western region of Paraná State (Brazil), adopting the methodology of Johnson (2006). The study area is characterized by outcrops of basaltic rocks of Cretaceous age. The degree of channel stability was analyzed at 46 structures (18 bridges, 15 culverts box, 7 culverts pipe and 6 small bridges). We selected all crossings structures located in the Paraná Basin III along paved roads, positioned outside the urban area. Among the crossings structure, 14 were classified as excellent level of stability and level 32 as good. There was no point with fair or poor stability. The predominance of soils with low erodibility (Oxisols and Ultisols) derived from basaltic rocks provide greater stability to streams banks which mostly show vertical phases. It was noted that in culverts (box and pipe), the stability of channels tends to lower than the bridges. / As obras de engenharia como pontes, pontilhões, bueiros tubulares de concreto e bueiros celulares de concreto são consideradas estruturas de transposição do talvegue. Elas têm como objetivo permitir a passagem de um curso d água abaixo e alteram as condições naturais dos rios, acarretando mudanças nos processos fluviais. O nível de estabilidade das margens e leitos fluviais em torno das estruturas de transposição do talvegue foi avaliado na bacia hidrográfica do Paraná III, Oeste do Paraná, adotando a metodologia de Johnson (2006). A região é caracterizada pelo afloramento de rochas basálticas de idade cretácea que integra a unidade morfoescultural do Terceiro Planalto Paranaense, sub-dividido na área em apreço em quatro sub-unidades: Planaltos de Cascavel, São Francisco, Campo Mourão e Foz do Iguaçu. O grau de estabilidade do leito e das margens foi analisado em 46 pontos (18 pontes, 15 bueiros em célula de concreto, sete bueiros tubulares de concreto e seis pontilhões). Foram alvo dos levantamentos as estruturas situadas em estradas federais, estaduais e municipais asfaltadas posicionadas fora das áreas urbanas. Dentre os pontos observados, 14 estruturas foram classificadas como de nível excelente de estabilidade e 32 como de nível bom. Não houve nenhum ponto com estabilidade regular ou ruim. O predomínio de Latossolos e Nitossolos na área de estudo proporcionou estabilidade física nas margens dos cursos de água que em sua maioria apresentam fases com 90º de declividade. Com este estudo pode-se identificar as condições de estabilidade das estruturas de transposição do talvegue dentro da bacia do Paraná III. Foi constatado que nos bueiros (tubulares ou celulares), a estabilidade dos canais tende a ser menor do que nas pontes e pontilhões.

Made available in DSpace on 2017-05-12T14:42:52Z (GMT). No. of bitstreams: 1 Leandro_Neri_Bortoluzzi.pdf: 4120006 bytes, checksum: e870dd7340723061217fb4d7fdece089 (MD5) Previous issue date: 2012-05-03 / The bridges and culverts alter the natural conditions of rivers, causing changes in fluvial processes. The level of stability of river banks and beds around crossing structures was evaluated in the Paraná III watershed, Western region of Paraná State (Brazil), adopting the methodology of Johnson (2006). The study area is characterized by outcrops of basaltic rocks of Cretaceous age. The degree of channel stability was analyzed at 46 structures (18 bridges, 15 culverts box, 7 culverts pipe and 6 small bridges). We selected all crossings structures located in the Paraná Basin III along paved roads, positioned outside the urban area. Among the crossings structure, 14 were classified as excellent level of stability and level 32 as good. There was no point with fair or poor stability. The predominance of soils with low erodibility (Oxisols and Ultisols) derived from basaltic rocks provide greater stability to streams banks which mostly show vertical phases. It was noted that in culverts (box and pipe), the stability of channels tends to lower than the bridges. / As obras de engenharia como pontes, pontilhões, bueiros tubulares de concreto e bueiros celulares de concreto são consideradas estruturas de transposição do talvegue. Elas têm como objetivo permitir a passagem de um curso d água abaixo e alteram as condições naturais dos rios, acarretando mudanças nos processos fluviais. O nível de estabilidade das margens e leitos fluviais em torno das estruturas de transposição do talvegue foi avaliado na bacia hidrográfica do Paraná III, Oeste do Paraná, adotando a metodologia de Johnson (2006). A região é caracterizada pelo afloramento de rochas basálticas de idade cretácea que integra a unidade morfoescultural do Terceiro Planalto Paranaense, sub-dividido na área em apreço em quatro sub-unidades: Planaltos de Cascavel, São Francisco, Campo Mourão e Foz do Iguaçu. O grau de estabilidade do leito e das margens foi analisado em 46 pontos (18 pontes, 15 bueiros em célula de concreto, sete bueiros tubulares de concreto e seis pontilhões). Foram alvo dos levantamentos as estruturas situadas em estradas federais, estaduais e municipais asfaltadas posicionadas fora das áreas urbanas. Dentre os pontos observados, 14 estruturas foram classificadas como de nível excelente de estabilidade e 32 como de nível bom. Não houve nenhum ponto com estabilidade regular ou ruim. O predomínio de Latossolos e Nitossolos na área de estudo proporcionou estabilidade física nas margens dos cursos de água que em sua maioria apresentam fases com 90º de declividade. Com este estudo pode-se identificar as condições de estabilidade das estruturas de transposição do talvegue dentro da bacia do Paraná III. Foi constatado que nos bueiros (tubulares ou celulares), a estabilidade dos canais tende a ser menor do que nas pontes e pontilhões.

Cette recherche s’inscrit dans un ensemble de travaux récents qui ont pour objet la contribution des Européens aux processus de création et d’évolution du jazz. Les migrants européens du XIXe et du début du XXe siècle véhiculent avec eux des singularités culturelles qui marquent la musique américaine. Le rôle des Tsiganes et de leurs représentations outre-Atlantique méritent d’être étudiés. Notre démarche historique s’appuie sur l’établissement d’un corpus issu de la lecture de la presse américaine des années 1880 aux années 1940, confronté à des sources variées dans une perspective pluridisciplinaire (histoire de l’art, musique et géographie). Un plan croisé permet d’étudier dans un premier temps la réception de l’image des Tsiganes dans les divertissements américains, dans la musique romantique et dans le jazz. Nous observons l’omniprésence du thème tsigane, l’apparition d’un véritable mythe et son appropriation américaine. Dans un second temps, nous montrons dans quelle mesure les Tsiganes et leurs musiques contribuent à définir le jazz et ses origines. Enfin, nous analysons dans une troisième partie la circulation des Tsiganes en Amérique et leur installation dans les grandes villes des États-Unis où des musiciens tsiganes jouent du jazz. / This academic research work is part of a series of recent studies whose aim is to show to what extent Europeans contributed to the birth of jazz and how they marked the development of this new kind of music. American music bears the stamp of the cultural idiosyncrasies that 19th and 20th century European migrants brought along. It is worthwhile focusing on the role played by Gypsies and the way they were perceived across the Atlantic. The reading of the American press from the 1880s to the 1940s, together with a wide variety of other sources, has provided a solid basis for a historical analysis with a multidisciplinary approach including art history, music and geography. A double-entry framework allows one to first study how Gypsies were perceived and represented in American entertainments, romantic music and jazz. What is noticeable is the omnipresence of the Gypsy theme, the emergence of a myth and its Americanization. Secondly, one can see the way Gypsy musics help define jazz music and give clues as to its origins. The third part is devoted to the Gypsies’ nomadic way of life throughout the United States and their settling in large cities where Gypsy musicians played jazz.

Winter roads, built from compacted snow and I or ice, are common throughout the circumpolar North. They are considered effective and economical means of providing seasonal access into permafrost terrain while minimizing the potential for environmental damage. The purpose of this study is an appraisal of long-term environmental impacts of winter roads by comparative assessment of terrain morphology, microclimate, permafrost, soils, and vegetation, on winter road right-of-ways and in adjacent undisturbed control areas.

While roads can present weak to complete barriers to wildlife, depending on the animal and traffic volume, mitigations such as under-crossings and green bridges on highways at least partially increase the permeability of the landscape to some of these species. The few studies evaluating the effectiveness of these structures for at least three years typically focused on a single species. Here, we monitored the crossing structure under Boeckman Road, in Wilsonville Oregon, for wildlife activity across summer seasons for ten years, since construction of the road and subsequent opening to traffic. This long-term multi-species dataset, which includes monitoring when the road was closed to traffic has provided a unique opportunity. Wildlife activity was collected using sand track pads monitored during summer seasons from 2009 to 2018. Wildlife activity showed a significant community level response from year to year and species-specific responses to year, vegetation change, disturbance, detection area, and previous experimental additions of artificial light. Roads create barriers to animal movement through collisions and habitat fragmentation. Investigators have attempted to use traffic volume, the number of vehicles passing a point on a road segment, to predict effects to wildlife populations approximately linearly and along taxonomic lines; however, taxonomic groupings cannot provide sound predictions because closely related species often respond differently. We assess the role of wildlife behavioral responses to traffic volume as a tool to predict barrier effects from vehicle-caused mortality and avoidance, to provide an early warning system that recognizes traffic volume as a trigger for mitigation, and to better interpret roadkill data. We propose four categories of behavioral response based on the perceived danger to traffic: Nonresponders, Pausers, Speeders, and Avoiders. By considering a species' risk-avoidance response to traffic, managers can make more appropriate and timely decisions to mitigate effects before populations decline or become locally extinct. Barriers to animal movement can isolate populations, impacting their genetic diversity, susceptibility to disease, and access to resources. Barriers to movement may be caused by artificial light, but few studies have experimentally investigated the effects of artificial light on movement for a suite of terrestrial vertebrates. Therefore, we studied the effect of ecological light pollution on animal usage of a bridge under-road passage structure. On a weekly basis, sections of the structure were subjected to different light treatments including no light added, followed by a Reference period when lights were off in all the structure sections. Findings suggest that artificial light may be reducing habitat connectivity for some species though not providing a strong barrier for others. Through the work conducted herein we provide contributions to the understanding of how elements of the built environment impact wildlife communities ability to move across the landscape. Additionally, we provide new tools to support resource managers in barrier mitigation and connectivity planning. Habitat fragmentation effects are a complex set of issues that require resources and collaboration to reach meaningful solutions. The work presented here can also support decision-making, communication, and collaborative efforts that will ultimately result in on-the-ground impacts to reduce fragmentation effects and mitigate existing barriers effectively to promote the long-term viability of wildlife and the systems they depend on.

This thesis details the development of a model of driver behaviour at railway level crossings that allows the probability of an accident under different conditions and interventions to be calculated. A method for classifying different crossings according to their individual risk levels is also described.