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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.
91

Citizens and Contemporary Science Ways to dialogue in science centre contexts.

Lundberg, Karin January 2005 (has links)
The current paper presents a study conducted at At-Bristol Science Centre, UK. It is a front-end evaluation for the “Live Science Zone” at At-Bristol, which will be built during the autumn of 2004. It will provide a facility for programmed events and shows, non-programmed investigative activities and the choice of passive or active exploration of current scientific topics. The main aim of the study is to determine characteristics of what kind of techniques to use in the Live Science Zone. The objectives are to explore what has already been done at At-Bristol, and what has been done at other science centres, and to identify successful devices. The secondary aim is mapping what sorts of topics that visitors are actually interested in debating. The methods used in the study are deep qualitative interviews with professionals working within the field of science communication in Europe and North America, and questionnaires answered by visitors to At-Bristol. The results show that there are some gaps between the intentions of the professionals and the opinions of the visitors, in terms of opportunities and willingness for dialogue in science centre activities. The most popular issue was Future and the most popular device was Film.
92

Devine qui vient dîner … : graines des villes et graines des champs, ou l'impact de l'agriculture péri-urbaine sur les oiseaux des jardins / Guess who comes to dinner ... : seeds of towns and seeds of fields, or the impact of suburban agriculture on garden birds

Pierret, Pauline 11 January 2018 (has links)
Nourrir les oiseaux dans les jardins privés est une activité très répandue en Occident. Elle fournit une remarquable opportunité de recherche et de suivi des populations d’oiseaux en hiver sur de larges échelles spatio-temporelles, en impliquant les citoyens dans des programmes de science participative. Nous avons utilisé le programme Oiseaux des Jardins, un programme de science participative coordonné par la Ligue de Protection des Oiseaux, pour étudier sur une grande échelle spatiale les variations d’abondance d’oiseaux en hiver dans les jardins qui fournissent de la nourriture. Le but de cette thèse est de comprendre quels paramètres peuvent expliquer les visites des oiseaux dans les jardins en hiver, saison traditionnellement considérée comme la plus décisive pour leur survie. Nous montrons que les jardins distribuant de la nourriture, proches de milieux agricoles intensifs, attirent les oiseaux en réponse à une raréfaction des ressources alimentaires naturelles, causée par l’intensité des pratiques agricoles. Cette relation est encore plus forte pour les espèces spécialistes des milieux agricoles. Les variations d’abondance d’oiseaux dans les jardins fluctuent selon les années et les conditions météorologiques, sans présenter de pattern de réponse commun entre espèces, en raison de leur biologie et écologie différentes. Ce suivi des oiseaux en hiver reflète également la tendance négative de population de plusieurs granivores, connue en France ou en Europe en période de reproduction, confirmant que l’utilisation des jardins avec mangeoires est un bon moyen de suivre les tendances des populations d’oiseaux. Nous suspectons que les variations d’abondances à l’échelle spatiale peuvent également refléter l’effet d’activités humaines, telles que le braconnage des passereaux, mais un travail supplémentaire est nécessaire pour confirmer cette hypothèse. Les résultats de cette thèse peuvent également aider au maintien des espèces granivores en déclin, en apportant des conseils adaptés à la distribution de nourriture de substitution pour les oiseaux dans les paysages agricoles intensifs, tout en continuant à engager le public dans le suivi et la protection de la nature. / Supplementary feeding of wild birds in private backyards is a globally widespread pastime. It provides a wonderful opportunity for research and survey of winter bird populations at spatial and temporal large-scales by involving householders in citizen science programs. We used data from the French national garden birdwatch scheme, a citizen science program operated by the Ligue de Protection des Oiseaux, to study winter bird abundance variations in gardens which provided food supply, at a large spatial scale. This thesis aims to understand which factors influence the visit of gardens by birds during winter, a season traditionally pointed out to have the greatest impact on passerine survival. We highlighted that gardens with feeders located close to intensively cultivated farmland attract birds as a response of the countryside natural resource scarcity leads by intensive agricultural practices. This relationship being stronger for farmland seedeater species. Variations in the use of garden by birds also fluctuate between years and with weather conditions, but the variations were not similar among species. This being consistent with the expected influence of their ecological and biological differences. This garden bird survey in winter also reflected the global negative trends observed for some granivorous species in France or Europe during the breeding season, confirming that the use of garden bird feeders by wild bird species offers a new tool to survey the global population trends. We also suspect that variation in abundance could mirror spatial differences, and maybe mirror human activities impacts such as poaching, but this part requires further investigation. Finally, our work could be beneficial for maintaining declining seedeater species, by advising to supply birds with winter food in garden located in intensive agricultural landscape, while continuing to engage the public with nature.
93

Forest ecology in a changing world : effective ground-based methods for monitoring temperate broadleaved forest ecosystem dynamics in relation to climate change

Smith, Alison M. January 2018 (has links)
The impacts of climate change on temperate forests are predicted to accelerate, with widespread implications for forest biodiversity and function. Remote sensing has provided insights into regional patterns of vegetation dynamics, and experimental studies have demonstrated impacts of specific changes on individual species. However, forests are diverse and complex ecosystems. To understand how different species in different forests respond to interacting environmental pressures, widespread ground-based monitoring is needed. The only practical way to achieve this is through the involvement of non-professional researchers, i.e., with citizen science. However, many techniques used to identify subtle changes in forests require expensive equipment and professional expertise. This thesis aimed to identify practical methods for citizen scientists to collect useful data on forest ecosystem dynamics in relation to climate change. Methods for monitoring tree phenology and canopy-understorey interactions were the main focus, as tree phenology exerts strong control on understorey light and forest biodiversity, and is already responding to climate change. The response of understorey vegetation to canopy closure in four woodlands from a single region of England (Devon) was examined in detail. These geographically close woodlands differed considerably in their composition and seasonal dynamics. The spring period was particularly important for herb-layer development, and small variations in canopy openness had important effects on herb-layer cover and composition. This work highlights the need to monitor a range of different woodlands at the regional scale, with sufficient resolution to pick up small but crucial differences through time. Citizen scientists could help to collect such data by monitoring herb-layer cover and changes in the abundance of key species, alongside monitoring the overstorey canopy. The spring leaf phenology of four canopy trees (ash, beech, oak and sycamore) were monitored intensively in one woodland using a range of methods: counts, percentage estimates and photography. First budburst and leaf expansion dates were compared with estimates of leaf expansion timing and rate, derived from time-series data using logistic growth models. Frequently used first-event dates were potentially misleading due to high variation in leaf development rates within and between species. Percentage estimates and counts produced similar estimates of leaf expansion timing and rate. A photo-derived greenness index produced similar estimates of timing, but not rate, and was compromised by practical issues of photographing individual crowns in closed canopy woodland. Citizen science should collect time-series data instead of frequently-used first event dates―visual observations offer the most practical way to do this, but further work is needed to test reliability with citizen scientists. Given high intra- and inter-species variation in tree phenology, whole forest canopies need to be monitored to infer canopy closure timing. Canopy openness was assessed using sophisticated hemispherical photography and a range of low-cost alternatives, across four Devon woodlands over a year. Visual estimates and ordinary photography were too coarse to identify fine-scale variation in canopies. Smartphone fisheye photography analysed with free software was identified as a reliable surrogate for estimating relative, though not absolute, canopy openness. The method has high potential as a citizen science tool, as different phone models and users gave similar canopy openness estimates. In a detailed follow-up study, smartphone fisheye photography, hemispherical photography and visual observations of leaf expansion were used every other day to characterise spring canopy development. Logistic growth models estimated canopy closure timing and rate. Visual observations identified much earlier canopy development than either photographic method. Smartphone fisheye photography performed comparably to hemispherical photography. There is good potential for practical application of smartphone fisheye photography, as similar canopy closure estimates were gained from photos taken once every two weeks. The research in this thesis identifies a range of methods suitable for widespread monitoring of forest ecosystem dynamics in relation to climate change. Developing a smartphone app for automatic analysis and submission of canopy images will be an important next step to enabling widespread use. A pilot project is underway to begin testing methods with citizen scientists. Further research into data quality with citizen scientists is needed before the methods can be rolled out widely with confidence.
94

Pathways of Knowing: Integrating Citizen Science and Critical Thinking in the Adult ELL Classroom

January 2012 (has links)
abstract: This action research study examines what common perceptions and constructs currently exist in educating adult immigrants in Arizona and considers how might the integration of citizen science with the current English curriculum promote higher order thinking and educational equity in this population. A citizen science project called the Mastodon Matrix Project was introduced to a Level 2 ELAA (English Language Acquisition for Adults) classroom and aligned with the Arizona Adult Standards for ELAA education. Pre and post attitudinal surveys, level tests, and personal meaning maps were implemented to assess student attitudes towards science, views on technology, English skills, and knowledge gained as a result of doing citizen science over a period of 8 weeks. / Dissertation/Thesis / Ed.D. Educational Leadership and Policy Studies 2012
95

Validating Citizen Science data for use in the design and management of constructed wetlands: a case study of Tufted Duck and Eurasian Teal.

Chamberlain, Richard January 2018 (has links)
Citizen science offers a potentially powerful tool for the environmental scientist to access large data sets over increasingly greater time scales. Given the ease of which information can be reported or shared online and the increase in community interest there is an overwhelming amount of data available. But two major questions remain; is the data reliable and how is it best used? This study addresses the first question by testing the ability of such data from Artportalen, Sweden’s Species Gateway for reporting observations of birds (and other flora and fauna), to reflect patterns in the presence and absence of breeding records of Tufted Duck (Aythya fuligula) and Eurasian Teal (Annas crecca). This was done by undertaking wetland assessments in a set of constructed wetland sites from Artportalen in Halland, Southern Sweden, with breeding records of the target species. A literature review was also undertaken to explore the existing ecological knowledge of breeding habitat requirements for each species. Physical and biological characteristics from the wetlands visited were then qualitatively compared to the existing ecological knowledge for each species’ preferred breeding habitat. This method resulted in some support for the reliability of this particular Citizen Science data, in that it reflected Tufted Duck’s preference to breed in wetlands closer to the coast, that provided some form of cover or screening around the edges and which had a large proportion of their shoreline bordered by tall emergent vegetation. Conversely, it reflected Eurasian Teal’s preference for inland wetlands that were closer to relatively open natural freshwater bodies, where tall emergent vegetation wasn’t as abundant. How this and other Citizen Science data can be used in the design and management of constructed wetlands for conservation purposes in light of these results is then discussed.
96

Local and regional factors correlating with long term population change in Gentianella campestris

Löfqvist, Zandra January 2018 (has links)
The decrease of semi-natural grasslands in Europe during the last decade has made several previously common species rare or declining in numbers. One of these species is the endangered field gentian Gentianella campestris, which has been proposed as an important indicator species for semi-natural grasslands. Previous studies have highlighted the importance of consistent management and shown how local conditions affect the species. Less is known about how the population is affected by isolation and changes in the surrounding landscape, both of which are potential consequences of habitat loss.This study utilized long term citizen science data on the population changes to explore if local and regional factors, such as connectivity could explain the rapid decline and local extinctions that the field gentian population in Östergötland, Sweden, has experienced since the beginning of the 1990’s. Generalized linear models showed that the declining field gentian population can partly be explained by changes in the surrounding landscape which has led to decreased connectivity of semi-natural grasslands. The study also indicate that there is a need for future management plans to consider the surrounding landscape on a distance of 1-3 km from field gentian localities as this scale seems to be the most important.
97

Combined decision making with multiple agents

Simpson, Edwin Daniel January 2014 (has links)
In a wide range of applications, decisions must be made by combining information from multiple agents with varying levels of trust and expertise. For example, citizen science involves large numbers of human volunteers with differing skills, while disaster management requires aggregating information from multiple people and devices to make timely decisions. This thesis introduces efficient and scalable Bayesian inference for decision combination, allowing us to fuse the responses of multiple agents in large, real-world problems and account for the agents’ unreliability in a principled manner. As the behaviour of individual agents can change significantly, for example if agents move in a physical space or learn to perform an analysis task, this work proposes a novel combination method that accounts for these time variations in a fully Bayesian manner using a dynamic generalised linear model. This approach can also be used to augment agents’ responses with continuous feature data, thus permitting decision-making when agents’ responses are in limited supply. Working with information inferred using the proposed Bayesian techniques, an information-theoretic approach is developed for choosing optimal pairs of tasks and agents. This approach is demonstrated by an algorithm that maintains a trustworthy pool of workers and enables efficient learning by selecting informative tasks. The novel methods developed here are compared theoretically and empirically to a range of existing decision combination methods, using both simulated and real data. The results show that the methodology proposed in this thesis improves accuracy and computational efficiency over alternative approaches, and allows for insights to be determined into the behavioural groupings of agents.
98

Examining the structures and practices for knowledge production within Galaxy Zoo : an online citizen science initiative

Bantawa, Bipana January 2014 (has links)
This study examines the ways in which public participation in the production of scientific knowledge, influences the practices and expertise of the scientists in Galaxy Zoo, an online Big Data citizen science initiative. The need for citizen science in the field of Astronomy arose in response to the challenges of rapid advances in data gathering technologies, which demanded pattern recognition capabilities that were too advanced for existing computer algorithms. To address these challenges, Galaxy Zoo scientists recruited volunteers through their online website, a strategy which proved to be remarkably reliable and efficient. In doing so, they opened up the boundaries of scientific processes to the public. This shift has led to important outcomes in terms of the scientific discovery of new Astronomical objects; the creation and refining of scientific practices; and the development of new forms of expertise among key actors while they continue to pursue their scientific goals. This thesis attempts to answer the over-arching research question: How is citizen science shaping the practices and expertise of Galaxy Zoo scientists? The emergence of new practices and development of the expertise in the domain of managing citizen science projects were observed through following the work of the Galaxy Zoo scientists and in particular the Principal Investigator and the project's Technical Lead, from February 2010 to April 2013. A broadly ethnographic approach was taken, which allowed the study to be sensitive to the uncertainty and unprecedented events that characterised the development of Galaxy Zoo as a pioneering project in the field of data-intensive citizen science. Unstructured interviewing was the major source of data on the work of the PI and TL; while the communication between these participants, the broader Science Team and their inter-institutional collaborators was captured through analyses of the team emailing list, their official blog and their social media posts. The process of data analysis was informed by an initial conceptualisation of Galaxy Zoo as a knowledge production system and the concept of knowledge object (Knorr-Cetina,1999), as an unfolding epistemic entity, became a primary analytical tool. Since the direction and future of Galaxy Zoo involved addressing new challenges, the study demanded periodic recursive analysis of the conceptual framework and the knowledge objects of both Galaxy Zoo and the present examination of its development. The key findings were as follows. The involvement of public volunteers shaped the practices of the Science Team, while they pursued robust scientific outcomes. Changes included: negotiating collaborations; designing the classification tasks for the volunteers; re-examining data reduction methods and data release policies; disseminating results; creating new epistemic communities; and science communication. In addition, new kinds of expertise involved in running Galaxy Zoo were identified. The relational and adaptive aspects of expertise were seen as important. It was therefore proposed that the development of the expertise in running citizen science projects should be recognised as a domain-expertise in its own right. In Galaxy Zoo, the development of the expertise could be attributed to a combined understanding of: the design principles of doing good science; innovation in methods; and creating a dialogic space for scientists and volunteers. The empirical and theoretical implications of this study therefore lie in (i) identifying emergent practices in citizen science while prioritising scientific knowledge production and (ii) a re-examination of expertise for science in the emerging context of data-intensive science.
99

Stopover ecology of migrating birds in Indiana

Jessica M Outcalt (8752419) 24 April 2020 (has links)
<div> <div> <div> <p>Billions of birds migrate annually between breeding and wintering habitats, following transient resources. Though a majority of time is spent in breeding and wintering habitats, habitats used during the migratory periods are especially important for migrating birds. Migration and stopovers, where birds rest and refuel before continuing a migratory journey, are critical points in a bird’s annual lifecycle, and are important ecologically, socially, and economically. Populations of migratory birds are declining on a global scale, however, and proper management is vital to their persistence in an urbanizing environment. Indiana in the Midwestern United States is an important area in which to study stopover ecology of migratory birds, as it is a fragmented forest- urban-agricultural matrix almost entirely managed through private ownership. In this dissertation, I studied three questions of stopover ecology within the landscape context of the Midwestern United States, primarily using weather surveillance radar and eBird citizen science data. </p> <p><br></p><p>First, I studied spatiotemporal changes over an 11-year period (autumn 2005-2016 and spring 2006-2017) in densities of nocturnally migrating birds at two radar stations in Indiana. I found that mean density of migratory birds stopping over in Indiana declined by approximately 6.8% annually, but variability in stopover site use increased over the same period. This is consistent with other work completed on continental scales, and highlights the need for further conservation of migratory birds. Second, I studied patterns of stopover site use in Indiana during spring 2016- 2017 and autumn 2015-2016, identifying landscape and local factors associated with those patterns. I used both traditional land cover characteristics and a novel approach using human socioeconomic measures to describe these patterns, and found that socioeconomics, particularly the size of a housing unit, were among the most important predictors of migratory bird density in Indiana. The results from this study suggest that migratory birds are utilizing urban habitats, which are known to contain several novel hazards for birds, but that migratory birds will benefit greatly from interdisciplinary work focusing on urban habitats. Third, I explored a novel method of using weather surveillance radar and eBird citizen science data in combination with each other, to see if both measures provided similar estimates of bird abundances during stopover. Though I found no correlation between the two, I argue that eBird and radar still provide important and complementary insights for the field of migration ecology. Finally, I provide guidelines for private landowners in Indiana on management for declining populations of migratory birds. </p> </div> </div> </div>
100

Mapování rozšíření kříženců jelenů evropských a jelenů sika v ČR s využitím občanské vědy a audionahrávek / Mapping of distribution of red deer and sika deer hybrids in Czechia using audio recordings - citizen science project

Nečasová, Monika January 2020 (has links)
In the Czech Republic, as in other parts of Europe (e.g., British Isles), the native European red deer (Cervus elaphus) has been hybridising with sika deer (C. nippon), which was introduced from East Asia. The hybrids are fertile, and, therefore, can backcross with their parental species and threaten their genetic integrity. Offsprings of such multiple crosses are very difficult to identify according to their morphological traits, while more reliable genetic methods are financially and logistically demanding. This work follows the study of Long et al. from 1998, which showed clear differences in vocalization between red deer, sika deer and the first generation of their hybrids, and thus suggested the third way how to identify hybrids - bioacoustic analysis. We decided to test this method in the Czech Republic in a citizen science project, the aim of which was to map the distribution of parent species and their hybrids using audiorecordings of rut vocalisation. To allow more detailed analysis, we also recorded our own recordings on a professional recording device with a directional microphone. In total, 451 recordings were collected, of which only 263 with a vocalization of 162 individuals were selected for further analysis. Recordings from previous studies from Ireland (Long et al. 1998; Wyman et...

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