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

Evaluating habitat use of female moose in response to large scale salvage logging practices in British Columbia, Canada

Francis, Alexandra 01 September 2020 (has links)
Global biodiversity is in decline as a result of unprecedented human alterations to the earth’s land cover. Understanding the ecological mechanisms of these large-scale changes in biodiversity is imperative in furthering our knowledge on the effects these alterations may have on animal behaviour and consequently on populations, allowing researchers and managers to effectively conserve species. During the last decade, there have been reports of moose populations both increasing and decreasing in North America due to a variety of factors (e.g., climate change, habitat disturbance, disease, etc.). Within British Columbia, wildlife managers have reported moose population declines of up to 50 – 70%, while other areas have remained stable. These changes have coincided, spatially and temporally, with the largest recorded mountain pine beetle (Dendroctonus ponderosae) outbreak. The outbreak resulted in extensive logging and road building in attempts to recover economic value from the beetle killed trees, resulting in drastic changes to the landscape. Understanding the effects that a highly disturbed landscape has on a species is critical for effective management and conservation. To investigate this, I examined the seasonal response of female moose to landscape change caused by the Mountain Pine Beetle outbreak and attendant salvage logging infrastructure in the Interior of British Columbia on the Bonaparte Plateau. First, I used a cluster analysis framework to develop biologically relevant seasons for female moose using individual movement and habitat use. I then used this temporal framework to develop seasonal home ranges for each individual moose. Second, I modeled the seasonal habitat selection of female moose to examine how moose respond to salvage logging infrastructure (i.e., dense road network and extensive cutblocks) using resource selection functions in an information-theoretic framework. We tested whether predation risk, forage availability or the cumulative effects of salvage logging best predicted moose space-use. Moose movement data clustered into five biologically relevant seasons, which were consistent with our biological and ecological knowledge of moose in the study area; however, these seasons and the size of the range differed from other seasons defined using alternative methods in the region. Across all seasons, the cumulative effects of forage availability and risk best predicted female moose distribution. In the calving and fall seasons, the top risk model best predicted moose habitat selection while the top forage availability model better explained moose habitat selection in spring, summer, and winter. Our results identified the importance of defining biological seasons using empirical data and how these seasons can differ from arbitrarily defined seasons, as well as the implications these can have in subsequent analysis and management. Additionally, we found that moose are seasonally trading the benefits of foraging for predation risk in these highly disturbed landscapes, using some aspects of salvage logging. My results bring perspective on how moose are using a highly disturbed landscape at the seasonal scale and a nuanced approach to landscape management. / Graduate
2

A Global Conservation Assessment of Temperate Forests: Status and Protection

Gagnon, Jennifer 19 December 2003 (has links)
Global biodiversity protection requires the development of protected areas that include representative samples of different ecosystems and their associated biodiversity (Dudley 1992, Scott et al. 2001a). I compared long-term decline and protection of forests in three major biomes; boreal, temperate and tropical. I found that forests in the temperate biome are less abundant and less protected than forests in the boreal and tropical biomes. I conducted regional analyses for five continents on the degree of protection of temperate forests across naturally occurring geographic and elevational ranges. My results indicate that protected temperate forests do not represent the full geographic and elevational range of naturally occurring temperate forests. Bias in location, elevation and slope of protected areas are present at both the regional and global scale. Better protection of temperate forests is needed if the diversity and resources associated with these forests types across their geographic range is to be preserved.
3

Nature as a Political Enactment Within the Global Biodiversity Debate and a Plea for a Process-Inspired  Transition Governance

Vullers, Pieter January 2020 (has links)
A revolution is brewing within global biodiversity governance as attempts to govern and to deal with biodiversity loss have not led to any substantial results. The underlying drivers of biodiversity loss keep adding to the total ecological predicament which in turn sets in motion an epistemological paradigm shift (episteme) with a call for transformative change. This shift of episteme confronts Western modern ways of thinking and challenges to leave bifurcated views of Nature behind. This leads to a shift in the great conservation debate towards a new Anthropocene conservation debate, where new discursive positions arise stressing to move beyond nature-culture dichotomies and beyond capitalism. These positions challenge the reformist and prosaic mainstream conservation regime of the Convention of Biological Diversity (CBD) with its tendency for rational problem-solving and incremental adjustments.  Contemporary process philosophers are now also creating their own discursive niche position within academia as “Earth bound”. This study draws from this position to shed a different light on the new Anthropocene conservation debate. It outlines how a “dogmatic image of thought” and how “the fallacy of the bifurcation of Nature” have created the conditions for the underlying drivers of biodiversity loss maintaining the mainstream conservation regime. “Living in harmony with nature” and “bending the curve of biodiversity loss” prove to be useful synergetic epistemic notions to break out of the dogmatic image and to leave bifurcation behind. Process-relational thinking can help understand how transition governance can support new policies that aim to create cross-scale alignments for local action within international negotiations.  Therefore, this study proposes a renewed process-inspired transition governance, which could help to find capacities that have yet remained unexercised. Based on speculative methods creating social-ecological imaginaries, these capacities can be discovered but this requires the global conservation community to see beyond the dogmatic image and bifurcation in the journey to living in harmony with nature in 2050, for which the epistemic notions of “living in harmony with nature” and “bending the curve of biodiversity loss” could turn out to be useful synergetic starting points.
4

Limitations in Global Information on Species Occurrences

Meyer, Carsten 13 May 2015 (has links)
Detaillierte Informationen über die Verbreitungsareale von Arten sind essentiell für die Beantwortung zentraler Fragen der Ökologie, Evolutionsbiologie und Biogeographie. Solche Informationen sind auch notwendig, um Naturschutzressourcen kostenwirksam zwischen verschiedenen Regionen und Maßnahmen zu verteilen. Unser Wissen über Artverbreitungen beruht vor allem auf Punktdaten, die das Vorkommen einer bestimmten Art an einem bestimmten Ort zu einem bestimmten Zeitpunkt belegen (nachstehend „Records“). Riesige Mengen solcher Records wurden über internationale Data-Sharing-Netzwerke mobilisiert, allen voran durch die Global Biodiversity Information Facility (GBIF). Auch wenn diese Netzwerke die Zugänglichkeit zu solchen Informationen enorm verbessert haben, ist unser Wissen über globale Artverbreitungen immer noch äußerst lückenhaft und von grober räumlicher Auflösung – der sogenannte Wallace’sche Wissensrückstand. Vorhandene Informationen enthalten zudem zahlreiche Unsicherheiten, Fehler und Daten-‘Biases’. Diese könnten durch Ort-spezifische Faktoren wie Zugänglichkeit oder durch artspezifische Faktoren, wie Entdeckungswahrscheinlichkeit, verursacht werden. Zukünftiges Sammeln und Mobilisieren von Informationen sollte so gestaltet werden, dass der erreichte Nutzen der Records für Forschung und Naturschutz maximiert wird. Hierfür ist ein tiefgehendes Verständnis der Lücken, Unsicherheiten und Biases in den Informationen sowie der sie verursachenden Faktoren notwendig. Bisher wurden diese Mängel in globalen Artverbreitungsinformationen niemals quantitativ untersucht. Mit meiner Dissertation liefere ich die ersten globalen Analysen zu Mängeln von digital verfügbaren Verbreitungsinformationen für terrestrische Wirbeltiere und Landpflanzen. Ich habe >300 Millionen Records für Landpflanzen und drei Gruppen terrestrischer Wirbeltiere (Amphibien, Säugetiere, Vögel) über GBIF abgerufen. Diese Informationen habe ich mit taxonomischen Datenbanken sowie unabhängigen Verbreitungskarten und Checklisten verbunden. Auf Grundlage der erstellten Datensätze habe ich unterschiedliche Formen von Informations-Mängeln für verschiedene taxonomische Gruppen und auf mehreren räumlichen Maßstäben untersucht. In Kapitel I habe Daten-Abdeckung sowie Daten-Unsicherheiten in Informationen zu Pflanzenvorkommen jeweils in Bezug auf Taxonomie, Raum und Zeit quantifiziert. Für diese insgesamt 6 Maße habe in anschließend Variation in den drei Dimensionen (Taxonomie, Raum, Zeit) gemessen. Zudem habe ich mithilfe von paarweisen Spearman-Rang-Korrelationen und Hauptkomponentenanalysen die Zusammenhänge zwischen diesen verschiedenen Formen von Informationsmängeln analysiert. In Kapitel II habe ich anhand von terrestrischen Wirbeltieren zwei spezielle Aspekte von Datenabdeckung zwischen geographischen Regionen verglichen: i) die Datendichte und ii) die Vollständigkeit der abgedeckten Arten. Durch Multi-Modell-Analysen habe ich die Effekte von zwölf potentiellen sozioökonomischen Einflussfaktoren auf Informationsmängel verglichen, und zwar einzeln für jede der drei Wirbeltiergruppen auf jeder von vier verschiedenen räumlichen Auflösungen. In Kapitel III habe ich anhand von Säugetieren drei Aspekte von Datenabdeckung zwischen einzelnen Arten verglichen: i) die Anzahl von Records pro Art, ii) die räumliche Abdeckung der Verbreitungsareale durch Records, und iii) den räumlichen Bias in der Abdeckung verschiedener Teile der Verbreitungsareale. Durch Multi-Modell-Analysen und Variations-Partitionierung habe ich die Effekte von verschiedenen Artmerkmalen, Größe und Form der Verbreitungsareale sowie von sozioökonomischen Faktoren untersucht. Diese Analysen habe ich auf globalem Maßstab sowie einzeln für sechs zoogeographische Gebiete durchgeführt. In meiner Dissertation habe ich in allen untersuchten Aspekten von Artverbreitungsinformationen starke Biases gefunden. Die Anzahl von Records variierte um mehrere Größenordnungen zwischen Arten und zwischen geographischen Gebieten. Verschiedene Maße von Datenabdeckung und Datenunsicherheiten zeigten klare taxonomische, geographische und zeitliche Muster. Ich fand beispielsweise Höchstwerte von taxonomischer Abdeckung in industrialisierten westlichen Ländern, aber auch in einigen tropischen Gebieten wie Mexiko. Im Gegensatz dazu gab es in weiten Teilen Afrikas und Asiens entweder gar keine oder nur sehr veraltete Informationen. Da taxonomische, räumliche und zeitliche Abdeckung jeweils durch die Anzahl der Records numerisch eingeschränkt sind, fand ich zwischen diesen Maßen gemäßigte bis starke positive Korrelationen. Maße von Datenunsicherheiten hingegen korrelierten kaum untereinander oder mit Datenabdeckungsmaßen. In Kapitel II habe ich den Einfluss von zwölf potentiellen sozioökonomischen Einflussfaktoren auf Datendichte und Datenvollständigkeit von geographischen Artgemeinschaften untersucht. Nur vier hatten einen durchweg für alle untersuchten Wirbeltiergruppen und räumlichen Auflösungen starken Einfluss. Dies waren der Endemitenreichtum, die räumliche Nähe zu Daten-beisteuernden Institutionen, politische Mitgliedschaft im GBIF-Netzwerk, sowie lokal verfügbare Forschungsgelder. Andere Faktoren, von denen man oft annimmt, dass sie eine große Rolle spielen würden, hatten einen erstaunlich geringen Einfluss, wie z.B. Verkehrsinfrastruktur oder Größe und Finanzausstattungen westlicher Daten-beisteuernder Institutionen. Meine Analysen in Kapitel III ergaben, dass die vier in Kapitel II identifizierten sozioökonomischen Schlüsselfaktoren ebenfalls einen starken Einfluss auf Artverbreitungsinformationen auf der Ebene von einzelnen Arten hatten. Jedoch unterschied sich ihre relative Wichtigkeit deutlich zwischen geographischen Gebieten. Zwischenartliche Unterschiede in Verbreitungsinformationen waren zudem sehr stark durch Größe und Form der Verbreitungsareale beeinflusst. Dies unterstützt meine Hypothese, dass diese geometrischen Faktoren die Wahrscheinlichkeit beeinflussen, dass sich Verbreitungsgebiete bestimmter Arten mit Untersuchungsgebieten von Feldforschern überschneiden, was wiederum Aufswirkungen auf die Wahrscheinlichkeiten hat, mit denen diese Arten besammelt werden. Entgegen unserer Annahmen hatten Artmerkmale wie etwa Nachtaktivität, die das Entdecken oder Sammeln bestimmter Arten wahrscheinlich machen sollten, kaum einen Einfluss auf zwischenartliche Unterschiede in Verbreitungsinformationen. Die Ergebnisse meiner Dissertation lassen wichtige Schlussfolgerungen darüber zu, wie mobilisierte Artverbreitungsinformationen effizient genutzt und verbessert werden können. Erstens belegen meine Ergebnisse schwerwiegende Mängel in digital verfügbaren Artverbreitungsinformationen, insbesondere für Gebiete und Arten von besonderer Wichtigkeit für den Naturschutz. Zweitens zeigen sie, dass für die allermeisten Arten feiner aufgelöste Informationen nur durch Artverbreitungsmodelle erreicht werden können, die mit geringen Datenmengen auskommen, die starke Datenunsicherheiten und Biases innehaben. Eine vielversprechende Methode, um in solchen Modellen mit Biases umzugeben, ist das explizite Einbeziehen der Bias-verursachenden Faktoren in die Modelle, und meine Ergebnisse bieten hilfreiche Anhaltspunkte für die Auswahl relevanter Faktoren. Drittens schaffen meine Ergebnisse eine empirische Grundlage zur Überwachung von Fortschritten in der Verbesserung weltweiter Artverbreitungsinformationen. Schließlich schafft mein Identifizieren der global wichtigsten Informations-limitierenden Faktoren sowie das Unterscheiden verschiedener Informationsaspekte eine Grundlage dafür, um Aktivitäten zu identifizieren, die Datenmängel effektiv beheben können. Als wichtigste Aktivitäten empfehle ich unter anderem i) das Unterstützen von Bemühungen zur Datenmobilisierung in Institutionen, die in geographischer Nähe zu datenarmen Gebieten liegen, ii) das Fördern von Kooperation zwischen großen Schwellenländern und Data-Sharing-Netzwerken, iii) die Durchführung von neuen Biodiversitäts-Surveys im zentralen Afrika und südlichen Asien, um weitgehend veraltete Informationen zu aktualisieren, und iv) das Verschieben des Fokus von Datensammel- und Datenmobilisierungsbemühungen auf Asien sowie Arten mit begrenzten Verbreitungsarealen.
5

Biogeografia da conservação frente à expansão agrícola: conflitos e prioridades / Conservation Biogeography faced with agricultural expansion: conflicts and priorities

DOBROVOLSKI, Ricardo 10 April 2012 (has links)
Made available in DSpace on 2014-07-29T16:23:34Z (GMT). No. of bitstreams: 1 Tese Ricardo Dobrovolski.pdf: 1981880 bytes, checksum: 8c60352c3d999171ab957f065b32a9db (MD5) Previous issue date: 2012-04-10 / Agriculture is the human activity with the greatest impact on the environment. Specifically, it represents the greatest threat to biodiversity. In the future, this activity should expand due to population growth, increased consumption and production of biofuels from food. To understand the possible impacts of this expansion on biodiversity, we used scenarios of land use change between 1970 and 2100 from IMAGE (Integrated Model to Access Global Environment) to test the following hypotheses: (i) areas considered as global priorities for conservation by international NGOs will be preferentially impacted by agricultural expansion in the XXI century, (ii) there is a conflict between the priority areas for carnivores conservation and agricultural expansion, and this conflict can be reduced by incorporating information on agricultural expansion in the prioritization process, (iii) the integration among countries for conservation planning may benefit both biodiversity and agricultural productivity, (iv) Brazilian protected areas will be impacted by agricultural expansion in the future and this impact will differ between protected areas of integral protection and those of sustainable use. We found that: (i) the impact on priority areas for conservation depends on the criteria by which they were set, so that areas defined by its high vulnerability are currently most affected than those of low vulnerability. Throughout the XXI century this impact is expected to increase, although the difference between the two types of priorities remains, except for High Biodiversity Wilderness Areas, defined by their low vulnerability in current time, but for which most pessimistic scenarios forecast an impact similar to priority areas of high vulnerability, (ii) there is a high spatial congruence between areas with high agricultural use in the future and priority areas for conservation of carnivores. This conflict can be reduced if the prioritization process include information on agricultural expansion; this incorporation, however, causes a profound change in the distribution of priority areas and reduces the number of protected carnivore populations, (iii) the integration of countries to create a set of priority areas for conservation that represents 17% of the land surface can protect 19% more mammal populations without reducing food production, compared to a strategy in which each country seeks to protect its territory independently, and (iv) the impact of agriculture in Brazil is expected to increase until the end of the century, threatening even the protected areas and their surroundings. This impact, however, should not be different between areas of sustainable use and those of integral protection. We conclude that agricultural expansion should remain a major threat to biodiversity in the future, even in areas of special interest for conservation. Conservation actions should be planned taking into account this threat in order to reduce their potential impacts. For this, countries like Brazil should strengthen its surveillance on agricultural expansion and on how this activity is developed. Furthermore, the integration of international conservation efforts should be pursued, given its benefits for biodiversity and food production. Finally, humanity must choose methods of agricultural production that reduce its impacts, including avoiding its future expansion, so as to meet the increasing needs of a human population globally. / A agricultura é a atividade humana com maior impacto sobre o ambiente. Particularmente, ela representa a maior ameaça à biodiversidade. No futuro, essa atividade deve expandir-se com o aumento populacional humano, o aumento do consumo e a produção de biocombustíveis a partir dos alimentos. Para entender os possíveis impactos dessa expansão sobre a biodiversidade, nós utilizamos cenários de mudança de uso do solo entre 2000 e 2100 do IMAGE (Integrated Model to Access Global Environment) para testar as seguintes hipóteses: (i) as áreas consideradas como prioridades globais de conservação pelas ONGs internacionais serão preferencialmente impactadas pela expansão agrícola no século XXI; (ii) há um conflito entre áreas prioritárias para a conservação de carnívoros e a expansão agrícola e esse conflito pode ser reduzido com a incorporação da informação sobre expansão agrícola no processo de priorização; (iii) a integração entre os países para o planejamento da conservação pode ser favorável à proteção da biodiversidade e à produção agrícola; (iv) no Brasil, as áreas protegidas serão impactadas pela expansão agrícola no futuro e esse impacto será diferente entre áreas de proteção integral e áreas de uso sustentável. Nós encontramos os seguintes resultados: (i) o impacto sobre as áreas prioritárias para a conservação depende dos critérios pelos quais elas foram definidas, assim, as áreas definidas por sua alta vulnerabilidade estão atualmente mais impactadas do que áreas de baixa vulnerabilidade. Ao longo do século XXI, o impacto geral da agricultura deve aumentar, mas a diferença entre os dois tipos de prioridades se mantém, exceto para as High Biodiversity Wilderness Areas, definidas por sua baixa vulnerabilidade, mas que nos cenários mais pessimistas podem ter um impacto agrícola semelhante ao das áreas de alta vulnerabilidade; (ii) há uma alta congruência espacial entre áreas com elevado uso agrícola no futuro e áreas prioritárias para a conservação de carnívoros; esse conflito pode ser reduzido se o processo de priorização incluir as informações sobre a expansão agrícola; a incorporação dessa informação, entretanto, provoca uma profunda alteração na distribuição das áreas prioritárias e reduz o número de populações de carnívoros protegidas; (iii) a integração entre os países para a criação de um conjunto de áreas prioritárias para conservação que represente 17% da superfície terrestre pode proteger 19% mais populações de mamíferos sem reduzir a produção de alimentos, se comparada a uma estratégia em que cada país busque proteger seu território independentemente; (iv) o impacto da agricultura no Brasil deve aumentar até o fim do século XXI, ameaçando inclusive as áreas protegidas e o seu entorno. Esse impacto, porém, não deve ser diferente entre as áreas de uso sustentável e aquelas de proteção integral. Assim, a expansão agrícola deve continuar a ser uma importante ameaça à biodiversidade no futuro, atingindo inclusive áreas de especial interesse para a conservação. As ações de conservação devem ser planejadas levando em consideração essa ameaça, a fim de reduzir seus impactos potenciais. Para isso, países como o Brasil devem reforçar sua vigilância sobre a expansão agrícola e a maneira como essa atividade é desenvolvida. Além disso, a integração internacional dos esforços de conservação deve ser buscada, dados seus benefícios para a biodiversidade e para a produção de alimentos. E por fim, a humanidade deve optar por formas de produção agrícola que reduzam seus impactos, inclusive evitando sua expansão futura, mas que possam satisfazer as necessidades da população humana globalmente.

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