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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

Moving from Landscape Connectivity Theory to Land Use Planning Practice: Ontario as a Case Study

Meyfarth O'Hara, Elke 10 June 2009 (has links)
Landscape connectivity is a concept that refers to a landscape's structural and functional continuity, allowing for the flow of water, nutrients, energy, organisms, genes, and disturbances at many spatial and temporal scales. The loss of landscape connectivity leads to ecosystem fragmentation, which in turn contributes to a decline in biodiversity and threatens many species around the world. The importance of maintaining landscape connectivity is becoming recognized as a fundamental principle in land use planning. The purpose of this dissertation is to examine how the theory of landscape connectivity has been applied in Ontario's land use planning policy and practice between 1970 and 2008. This includes evaluating the degree to which theory has been applied to practice in landscape connectivity planning. In addition, the work investigates the processes that facilitated the movement from theory to practice in planning for landscape connectivity. Broadly framed within the theories of conservation biology, the research approach is qualitative and the research design includes a literature review, content analysis, and case study research. This research found that there has been an evolution of theory to practice in planning for landscape connectivity in Ontario between 1970 and 2008. The introduction of conservation biology principles created a growing public awareness, which contributed to rising pressure on the Government of Ontario to reform its land use planning policies. The theory of landscape connectivity is included in key land use planning legislation and policies and is now an accepted part of planning for natural heritage in the province. The Ontario Municipal Board has regard for landscape connectivity as a legitimate planning concern. In the majority of cases in the last decade in which landscape connectivity was identified as a deciding factor, the Ontario Municipal Board ruled in favour of protecting landscape connectivity. Planners in Ontario are expected to plan for landscape connectivity, but Ontario’s planning law and policy does not provide strong direction to planners on the issue of landscape connectivity. Recommendations for the Government of Ontario, based on the research findings, include planning for landscape connectivity at a provincial scale, creating a guidance document specifically for landscape connectivity and revising the Provincial Policy Statement.
2

Moving from Landscape Connectivity Theory to Land Use Planning Practice: Ontario as a Case Study

Meyfarth O'Hara, Elke 10 June 2009 (has links)
Landscape connectivity is a concept that refers to a landscape's structural and functional continuity, allowing for the flow of water, nutrients, energy, organisms, genes, and disturbances at many spatial and temporal scales. The loss of landscape connectivity leads to ecosystem fragmentation, which in turn contributes to a decline in biodiversity and threatens many species around the world. The importance of maintaining landscape connectivity is becoming recognized as a fundamental principle in land use planning. The purpose of this dissertation is to examine how the theory of landscape connectivity has been applied in Ontario's land use planning policy and practice between 1970 and 2008. This includes evaluating the degree to which theory has been applied to practice in landscape connectivity planning. In addition, the work investigates the processes that facilitated the movement from theory to practice in planning for landscape connectivity. Broadly framed within the theories of conservation biology, the research approach is qualitative and the research design includes a literature review, content analysis, and case study research. This research found that there has been an evolution of theory to practice in planning for landscape connectivity in Ontario between 1970 and 2008. The introduction of conservation biology principles created a growing public awareness, which contributed to rising pressure on the Government of Ontario to reform its land use planning policies. The theory of landscape connectivity is included in key land use planning legislation and policies and is now an accepted part of planning for natural heritage in the province. The Ontario Municipal Board has regard for landscape connectivity as a legitimate planning concern. In the majority of cases in the last decade in which landscape connectivity was identified as a deciding factor, the Ontario Municipal Board ruled in favour of protecting landscape connectivity. Planners in Ontario are expected to plan for landscape connectivity, but Ontario’s planning law and policy does not provide strong direction to planners on the issue of landscape connectivity. Recommendations for the Government of Ontario, based on the research findings, include planning for landscape connectivity at a provincial scale, creating a guidance document specifically for landscape connectivity and revising the Provincial Policy Statement.
3

Modelling landscape connectivity for highly-mobile terrestrial animals: a continuous and scalable approach

Galpern, Paul 08 1900 (has links)
Assessments of landscape connectivity are increasingly required in natural resource management. Understanding how landscape structure affects the movement and dispersal of animals may be essential for ensuring the long-term persistence of species of conservation concern. Functional connectivity models describing how features on the landscape influence animal movement behaviour have been produced in two different ways. The resistance surface models landscape connectivity as its inverse, the resistance to movement and dispersal, while the landscape graph represents landscape connectivity by describing the relationships among resource patches. Both methods have limitations that make them less effective for modelling highly-mobile and wide-ranging species such as ungulates and carnivores. This thesis develops a method called grains of connectivity that combines the continuous representation of landscape connectivity provided by resistance surfaces and the scalability provided by landscape graphs to create a flexible modelling framework for these species. The first half of the thesis reviews the conceptual origins of the grains of connectivity method and examines its properties using simulated landscapes. In the second half, empirical evidence of movement and dispersal in a boreal woodland caribou (Rangifer tarandus caribou) population is used to validate functional connectivity hypotheses generated using the method. Connectivity for caribou at the temporal scale of generations is examined using a landscape genetics approach, while connectivity at the seasonal scale is assessed using the distribution of caribou telemetry locations. Grains of connectivity may be most useful for study systems where animals are not found exclusively in well-defined resource patches and there is uncertainty in the behavioural parameters influencing movement and dispersal. Additionally, the scalability of the analysis can be used to selectively remove spatial heterogeneity that may be uncorrelated with movement and dispersal giving an improved description of the pattern affecting the landscape connectivity process.
4

Modelling landscape connectivity for highly-mobile terrestrial animals: a continuous and scalable approach

Galpern, Paul 08 1900 (has links)
Assessments of landscape connectivity are increasingly required in natural resource management. Understanding how landscape structure affects the movement and dispersal of animals may be essential for ensuring the long-term persistence of species of conservation concern. Functional connectivity models describing how features on the landscape influence animal movement behaviour have been produced in two different ways. The resistance surface models landscape connectivity as its inverse, the resistance to movement and dispersal, while the landscape graph represents landscape connectivity by describing the relationships among resource patches. Both methods have limitations that make them less effective for modelling highly-mobile and wide-ranging species such as ungulates and carnivores. This thesis develops a method called grains of connectivity that combines the continuous representation of landscape connectivity provided by resistance surfaces and the scalability provided by landscape graphs to create a flexible modelling framework for these species. The first half of the thesis reviews the conceptual origins of the grains of connectivity method and examines its properties using simulated landscapes. In the second half, empirical evidence of movement and dispersal in a boreal woodland caribou (Rangifer tarandus caribou) population is used to validate functional connectivity hypotheses generated using the method. Connectivity for caribou at the temporal scale of generations is examined using a landscape genetics approach, while connectivity at the seasonal scale is assessed using the distribution of caribou telemetry locations. Grains of connectivity may be most useful for study systems where animals are not found exclusively in well-defined resource patches and there is uncertainty in the behavioural parameters influencing movement and dispersal. Additionally, the scalability of the analysis can be used to selectively remove spatial heterogeneity that may be uncorrelated with movement and dispersal giving an improved description of the pattern affecting the landscape connectivity process.
5

Large carnivore recolonization of Eastern North America: habitat connectivity and human dimensions

Winkel, Brianna M 01 September 2021 (has links)
Cougars (Puma concolor) have been recolonizing Midwestern North America over the past 2 decades with >950 cougar confirmations east of established populations. Management and public interest in habitat suitability and connectivity east of current cougar range have grown as confirmations increase and models predicting habitat connectivity and population viability for the Midwest show potential for breeding populations. However, although long-range dispersal and recolonization continues, no studies have assessed potential habitat associated with cougars throughout their historical range in eastern North America. I used ArcGIS, the Analytical Hierarchy Process, and geospatial data to model cougar habitat and potential dispersal corridors in eastern North America. The total amount of potential habitat was >2,400,000 km2 and mean patch size was 257,500 km2. Patches of habitat ranged in size from 3,868 km2 (Ozark Mountains) to >2,490,850 km2 (central and eastern Canada) with ≤53,643 km of dispersal corridors connecting patches. With cougars potentially recolonizing areas previously devoid of large carnivores, public acceptance of management efforts is pivotal for the success of their recolonization. However, targeted surveys assessing public perceptions and knowledge of cougars and red wolves (Canis rufus), who have faced similar extirpation in the Southeastern United States are limited. I mailed 20,000 questionnaires and 2,000 follow-up postcards to residents near areas of potential red wolf and cougar habitat in the Southeastern United States in 2020. I used cumulative link models to gauge the associations between sociodemographic predictor with respondent’s knowledge and attitude towards large carnivores. Total response rate was 4.6% with the majority of respondents identifying as male (53.6%), having a 4-year degree or above (54.1%), and 57 ± 16 (SE) years of age. Respondents’ knowledge and attitudes towards large carnivores were largely positive (≥63% positive) with higher education, older age, and current livestock ownership being largest predictors for responses. Attitudes towards red wolves were largely driven by knowledge of red wolves while attitudes towards cougars were primarily driven by livestock ownership. Livestock owners (71.5%) were concerned about safety of livestock in large carnivore habitat, and most respondents (61%) did not trust their local agency to effectively manage large carnivore populations. My research provides a foundation for wildlife managers to develop informed plans, educational programs, and policy decisions for potentially recolonizing large carnivore populations.
6

Proximate Cues and Ultimate Consequences for Natal Dispersal and Settlement in an Altered Forest Landscape: Influence of Experience, Behavior, and Habitat

Merrick, Melissa Jane, Merrick, Melissa Jane January 2016 (has links)
Natal dispersal is at the nexus of ecology, ethology, population genetics, and evolution. While abundant research exists on emigration and associated proximate and ultimate causes, less is known about exploration, settlement, and factors that influence settlement decisions. Further, the role of individual behavioral phenotypes in the domains of wildlife ecology and conservation, which include natal dispersal, is a recent and expanding area of inquiry. Understanding the relationships among individual phenotype, environmental conditions, and natal dispersal is increasingly important as landscapes become altered by disturbance, fragmentation, and climate change. I investigated natal dispersal in endangered Mt. Graham red squirrels (Tamiasciurus hudsonicus grahamensis), an isolated, peripheral subspecies of North American red squirrel persisting at the southern edge of the species' range. We tested hypotheses about the importance of proximate and ultimate drivers of emigration, dispersal distance, and settlement, and estimated perceived landscape connectivity within a mosaic of forest damage in the Pinaleño Mountains, Arizona. Compared to other red squirrel populations in North America, natal dispersal in Mt. Graham red squirrels is sex-biased and non-philopatric with mean dispersal distance over 8 times that observed in non-peripheral populations. Resources, indicated by mother's body mass in spring (a reflection of her intrinsic quality and territory quality) and individual body condition, contribute to individual behavioral tendencies for movement and exploration. Individuals with behavioral tendencies for movement and exploration dispersed the farthest, and for both males and females the longest observed dispersal distances and proportion of individuals dispersing occurred in a year of lowest food availability. Our research highlights the important role individual behavioral syndromes may play in observed heterogeneity in life history strategies with populations. Following emigration from the natal area, we provide evidence that individual dispersers rely upon forest structural cues similar to their natal area to select locations for settlement; the first test of natal habitat preference induction in a single vegetation community type. We used circuit theory to evaluate landscape connectivity and identify areas important for long-distance dispersal movements. Because single connectivity models may not adequately represent functional connectivity for an entire population, we summarized landscape connectivity across varying levels of landscape resistance to identify areas that promote movement and long-distance dispersal for individuals with different perceptions of landscape resistance. We show that composite connectivity models are a useful method to identify forest areas important for the promotion of long-distance movements as well as areas that constrain movement.
7

Hodnocení vlivu struktury krajiny na disperzi rysa ostrovida v Pošumaví / Assessment of the impact of landscape structure on the dispersion of lynx in Posumavi

Sladová, Michaela January 2014 (has links)
Assessment of the impact of landscape structure on the dispersion of lynx in Posumavi Abstract: The big predators are a traditional group of bioindicative species, whose presence shows the state of environment and landscape within a region. As these animals recolonize the cultural landscape of central Europe it's needed to understand their space requirements and habitat preferences. The lynx (Lynx lynx) has been one of the Sumava forest species since the 70's. After almost 40 years the population of lynx has spread from Sumava and Bavarian Forest to forested parts of Cesky Les, Smrcina and Novohradske hory and to both sides of state borders. However today's state of lynx population, stable number of animals or genetic variability is endangered by many factors. Long term viability of the lynx population is - besides poaching or illegal hunting − affected by the loss of suitable habitats and ongoing fragmentation of the landscape. One of the possible solutions of negative impacts is delineation and protection of landscape permeability of habitat corridors. They might have provide supply of new individuals to small, extinction prone population and at the same time they could reinforce overall fitness population. This thesis has three main objectives:1) evaluation of landscape fragmentation and connectivity in...
8

Fragmentace krajiny ČR dopravními stavbami - vývoj, současný stav a priority územní ochrany / Landscape fragmentation by line barriers in the Czech Republic - development, state of the art and priorities of territorial protection

Zýka, Vladimír January 2014 (has links)
Landscape fragmentation by line barriers in the Czech Republic - development, state of the art and priorities of territorial protection Abstract This paper deals with the problem of landscape fragmentation by linear structures and changes in land cover printed in Europe and the Czech Republic. The development of the fragmentation geometry consisting of transport infrastructure and urban areas is described in detail in the years 1920-2020. In this time boundary the development of measure of landscape fragmentation in the Czech Republic is evaluated. This paper examines also the quality of the current unfragmented landscape. The degree of landscape fragmentation refills the value of ecological integrity (according to Burkhard et al., 2009). The results of gap analysis define the most valuable areas of the Czech countryside, which are not covered by existing special protection area (NP, CHKO, Natura 2000). The resulting areas are also compared to the territorial system of ecological stability and migration important area for the large mammals. Keywords landscape fragmentation - landscape connectivity - ecological integrity - gap analysis of landscape protection
9

Exurban Development: Mapping, Locating Factors, and Ecological Impact Analysis using GIS and Remote Sensing

Shrestha, Namrata 31 August 2012 (has links)
Anthropogenic disturbance in a landscape can take various forms, including residential development, which has substantial impact on the world’s ecosystems. Exurban development, characterized by low density residential development outside urban areas, was and continues to be one of the fastest growing forms of residential development in North America. It has disproportionately large ecological impacts relative to its footprint, yet is mostly overlooked in scientific studies. Specifically, a lack of spatially explicit (disaggregate) data on exurban development at regional level has contributed to a very limited understanding of this interspersed low density development. The main goal of this dissertation is to provide an increased understanding of exurban development in terms of its location, locating factors, and conservation and ecological implications at regional level, especially to enable incorporation of exurban information in the decision making processes. For this I asked four specific questions in this dissertation: (i) Where exactly is exurban development? (ii) What are the most likely factors that influence exurban development location? (iii) How does current and future development conflict with conservation goals? And (iv) What is the extent of the exurban development’s ecological impacts? Using a heterogeneous landscape, the County of Peterborough (Ontario, Canada), as the case study this dissertation undertook a number of separate yet related analyses that collectively provided the improved understanding of exurban development. The investigation of traditionally used surrogates for development, like roads and census data, and a more direct remote sensing method, using moderate resolution SPOT/HRVIR imagery, provided insights and contributed to development of spatially explicit data on exurban development. The evaluation of several commonly hypothesized locating factors in relation to exurban development revealed some of the major influences on the location of this development, especially in the context of Ontario. This research contributed to our understanding of the future risks of land conversion and identification of potential conflict areas between development and conservation plans in the study area. Lastly, examining the ecological impact of exurban development including associated roads, in terms of functions such as barrier effects and landscape connectivity, highlighted the importance of these seldom included anthropogenic disturbances in land and conservation planning. The contributions of this research to the existing body of knowledge are threefold. First, this dissertation reveals the limitations associated with existing methods used to map exurban development and presents a relatively easy, effective, automated and operational method to delineate exurban built areas at regional level using GIS and remote sensing. Second, the analyses conducted in this dissertation repeatedly highlights the importance of incorporating fine level details on exurban development in land and conservation planning as well as ecological impact assessments and presents methods and tools that can systematically and scientifically integrate this information in decision making framework. Third, this study conducted one of a kind, comprehensive and spatially explicit study on exurban development in Canada, where there is near absence of such research. With the rarely available exurban built footprint data delineated for the study area, this study not only identified the potential locating factors, future conversion risk, and conflict areas between development and conservation plans, but also quantified ecological impact in terms of landscape function, namely barrier effects and landscape connectivity, using a relatively novel circuit theoretic approach that can directly inform land and conservation decision planning process.
10

Exurban Development: Mapping, Locating Factors, and Ecological Impact Analysis using GIS and Remote Sensing

Shrestha, Namrata 31 August 2012 (has links)
Anthropogenic disturbance in a landscape can take various forms, including residential development, which has substantial impact on the world’s ecosystems. Exurban development, characterized by low density residential development outside urban areas, was and continues to be one of the fastest growing forms of residential development in North America. It has disproportionately large ecological impacts relative to its footprint, yet is mostly overlooked in scientific studies. Specifically, a lack of spatially explicit (disaggregate) data on exurban development at regional level has contributed to a very limited understanding of this interspersed low density development. The main goal of this dissertation is to provide an increased understanding of exurban development in terms of its location, locating factors, and conservation and ecological implications at regional level, especially to enable incorporation of exurban information in the decision making processes. For this I asked four specific questions in this dissertation: (i) Where exactly is exurban development? (ii) What are the most likely factors that influence exurban development location? (iii) How does current and future development conflict with conservation goals? And (iv) What is the extent of the exurban development’s ecological impacts? Using a heterogeneous landscape, the County of Peterborough (Ontario, Canada), as the case study this dissertation undertook a number of separate yet related analyses that collectively provided the improved understanding of exurban development. The investigation of traditionally used surrogates for development, like roads and census data, and a more direct remote sensing method, using moderate resolution SPOT/HRVIR imagery, provided insights and contributed to development of spatially explicit data on exurban development. The evaluation of several commonly hypothesized locating factors in relation to exurban development revealed some of the major influences on the location of this development, especially in the context of Ontario. This research contributed to our understanding of the future risks of land conversion and identification of potential conflict areas between development and conservation plans in the study area. Lastly, examining the ecological impact of exurban development including associated roads, in terms of functions such as barrier effects and landscape connectivity, highlighted the importance of these seldom included anthropogenic disturbances in land and conservation planning. The contributions of this research to the existing body of knowledge are threefold. First, this dissertation reveals the limitations associated with existing methods used to map exurban development and presents a relatively easy, effective, automated and operational method to delineate exurban built areas at regional level using GIS and remote sensing. Second, the analyses conducted in this dissertation repeatedly highlights the importance of incorporating fine level details on exurban development in land and conservation planning as well as ecological impact assessments and presents methods and tools that can systematically and scientifically integrate this information in decision making framework. Third, this study conducted one of a kind, comprehensive and spatially explicit study on exurban development in Canada, where there is near absence of such research. With the rarely available exurban built footprint data delineated for the study area, this study not only identified the potential locating factors, future conversion risk, and conflict areas between development and conservation plans, but also quantified ecological impact in terms of landscape function, namely barrier effects and landscape connectivity, using a relatively novel circuit theoretic approach that can directly inform land and conservation decision planning process.

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