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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

Conectando florestas e primatas: as mudanças no uso da terra para a conservação do muriqui-do-norte (Brachyteles hypoxanthus Kuhl, 1820) em propriedades rurais / Connecting primates and forests: land use changes to conserve the spider monkey (Brachyteles hypoxanthus Kuhl, 1820) in rural properties

Crepaldi, Maria Otávia Silva 05 October 2015 (has links)
As mudanças no uso e na cobertura da terra, principalmente em áreas florestais, causam alterações ambientais em diversas escalas. Uma das suas consequências negativas é a fragmentação de habitats, que causa desequilíbrio nos diversos ecossistemas e perda de espécies e populações. Investigar os fatores que influenciam o aumento da cobertura florestal e as suas consequências para a conservação da biodiversidade é fundamental para o planejamento de políticas públicas ambientais, principalmente em regiões de ocorrência de espécies ameaçadas de extinção. No caso do muriqui-do-norte (Brachyteles hypoxanthus), um primata neotropical criticamente em perigo de extinção, a existência de conectividade entre fragmentos florestais remanescentes é um dos maiores limites para a sua conservação, pois mudanças no uso e na cobertura da terra serão necessárias. A conservação desse primata requer estratégias mais integradas do que apenas a criação de áreas protegidas, sendo necessário o envolvimento dos proprietários rurais, juntamente com os tomadores de decisão. A aplicação de instrumentos políticos econômicos, como compensações e pagamentos por serviços ambientais, pode ser uma estratégia para estimular proprietários rurais a participarem de programas de conservação da biodiversidade em terras privadas. O problema da pesquisa deste trabalho foi identificar os fatores que levaram ao aumento de áreas florestadas em propriedades rurais em regime familiar de exploração e as suas consequências à conservação da biodiversidade. A pesquisa foi desenvolvida no município de Santa Maria de Jetibá, ES, onde ocorrem populações do muriqui-do-norte e predominam as propriedades agrícolas familiares, nas quais tem ocorrido aumento de áreas florestadas, muitas delas fragmentadas. O trabalho foi dividido em três partes: Análise das mudanças de uso e da cobertura da terra entre 1970 e 2005, identificando os principais indutores do aumento da cobertura florestal em uma região de ocorrência do muriqui-do-norte; Descrição do perfil socioeconômico, da percepção e das motivações dos proprietários rurais para a conservação de serviços ecossistêmicos; Proposição de corredores estruturais para sete populações de muriqui-do-norte, baseada na permeabilidade da matriz e na aceitação dos donos da terra. Foram utilizados mapas de uso e cobertura da terra, censos agropecuários, entrevistas semiestruturadas, métodos de valoração e compensação de serviços ambientais baseados no mercado de bens substitutos e na preferência declarada, além de simulações dos corredores ecológicos no programa LORACS. A decisão de deixar áreas naturais na propriedade rural é fortemente influenciada por fatores econômicos. O aumento da produtividade, possibilitada pela tecnificação agrícola, permitiu a ampliação da cobertura florestal no município de Santa Maria de Jetibá. O perfil socioeconômico dos agricultores entrevistados e as características das propriedades nos permitem inferir sobre a importância dos instrumentos políticos econômicos, do tipo de agricultura praticada e da percepção ambiental para criar oportunidades de conservação da biodiversidade. Programas de conservação que têm como meta a efetivação de corredores de vegetação em áreas privadas e, consequentemente, a perda de áreas produtivas, podem utilizar instrumentos políticos econômicos, baseados na disposição a receber, no custo de oportunidade da terra e no custo de restauração ecológica, para serem mais atrativos aos proprietários rurais, motivando-os a romper as barreiras para sua aceitação. / The changes imposed in land use and land cover, especially in forest areas, produce environmental changes at various levels. One negative consequence is the habitat fragmentation, followed by disturbance in many ecosystems, such as the loss of species and its populations. The study of factors influencing the increase of forest cover and its consequences for the conservation of biodiversity is essential for the planning of environmental policies, particularly for the regions where endangered species occur. One critical factor for the conservation of the spider monkeys (Brachyteles hypoxanthus) - a neotropical primate critically endangered, is the connectivity between remaining forest fragments, because necessary changes in land use and land cover will happen. The above mentioned conservation requires more integrated strategies than just the creation of protected areas, whereas the involvement of landowners and decision makers are needed. The use of economic policy instruments, such as compensation and payments for environmental services, can provide a strategy to encourage landowners to participate in biodiversity conservation programs on their lands. The present research consists in identifying the leading factors to the increase of forested areas on lands in family regime of exploitation and its consequences for biodiversity conservation. This study has been conducted in Santa Maria de Jetibá, a county of Espírito Santo, Brazil, where there are populations of spider monkeys inside little farms, whose forested areas have been increased, but fragmented. This work comprehends three parts: - Analysis of land use and land cover change between 1970 and 2005, identifying the main drivers of forest cover increase, in a region where spider monkeys occur; - Study of the socioeconomic profile, the perception and motivations of landowners for the conservation of ecosystem services; - Proposition of structural corridors for seven populations of spider monkeys, based on the matrix permeability and acceptance of landowners. The employed resources are: land cover maps, agricultural census, semi-structured interviews, and methods of valuation and compensation of environmental services based on the market of substitute goods and the declared preference, as well as simulations of ecological corridors in LORACS program. The decision to leave natural areas on the farm is strongly influenced by economic factors. The increase in productivity enabled by agricultural mechanization, allowed the expansion of forest cover in farms of Santa Maria de Jetibá. The socioeconomic profile of farmers and the characteristics of their properties prompted the influence of economic policy instruments, the type agriculture and the environmental conscience among farmers, to create biodiversity conservation opportunities. Conservation programs aiming to lay vegetation corridors in private land and, consequently, the loss of productive areas, can be implemented by economic policy instruments, based on the economical compensation, in the land opportunity cost and cost of ecological restoration, bring down barriers of landowners against conservational programs.
2

Habitat linkages and highway mitigation using spatially-explicit GIS-based models

Jones, Andrew Charles 13 December 2012 (has links)
I identified suitable locations for highway wildlife crossing mitigations across the TransCanada Highway (TCH) in the area of Mount Revelstoke and Glacier National Park (MRGNP), British Columbia. Highways fragment natural landscapes leading to habitat loss, reduced ecosystem connectivity and direct wildlife mortality though motor vehicle collisions. Grizzly bears (Ursus arctos) are vulnerable to the effects of habitat and population fragmentation. Highway wildlife crossing mitigations improve ecosystem connectivity by increasing the permeability of transportation corridors to wildlife. I identified high-quality habitat patches using a resource selection function (RSF) based on 1,703 radio telemetry locations from 59 grizzly bears. Least-cost path analysis (LCP) among habitat patches identified 6 linkage zones across the TCH. Electric circuit theory was used to generate current maps that classify linkage zones as high-volume crossing areas or tenuous linkages. Linkage zones occurred where high-quality habitat aligned with physical features conducive to cross-valley wildlife dispersal.
3

Conectando florestas e primatas: as mudanças no uso da terra para a conservação do muriqui-do-norte (Brachyteles hypoxanthus Kuhl, 1820) em propriedades rurais / Connecting primates and forests: land use changes to conserve the spider monkey (Brachyteles hypoxanthus Kuhl, 1820) in rural properties

Maria Otávia Silva Crepaldi 05 October 2015 (has links)
As mudanças no uso e na cobertura da terra, principalmente em áreas florestais, causam alterações ambientais em diversas escalas. Uma das suas consequências negativas é a fragmentação de habitats, que causa desequilíbrio nos diversos ecossistemas e perda de espécies e populações. Investigar os fatores que influenciam o aumento da cobertura florestal e as suas consequências para a conservação da biodiversidade é fundamental para o planejamento de políticas públicas ambientais, principalmente em regiões de ocorrência de espécies ameaçadas de extinção. No caso do muriqui-do-norte (Brachyteles hypoxanthus), um primata neotropical criticamente em perigo de extinção, a existência de conectividade entre fragmentos florestais remanescentes é um dos maiores limites para a sua conservação, pois mudanças no uso e na cobertura da terra serão necessárias. A conservação desse primata requer estratégias mais integradas do que apenas a criação de áreas protegidas, sendo necessário o envolvimento dos proprietários rurais, juntamente com os tomadores de decisão. A aplicação de instrumentos políticos econômicos, como compensações e pagamentos por serviços ambientais, pode ser uma estratégia para estimular proprietários rurais a participarem de programas de conservação da biodiversidade em terras privadas. O problema da pesquisa deste trabalho foi identificar os fatores que levaram ao aumento de áreas florestadas em propriedades rurais em regime familiar de exploração e as suas consequências à conservação da biodiversidade. A pesquisa foi desenvolvida no município de Santa Maria de Jetibá, ES, onde ocorrem populações do muriqui-do-norte e predominam as propriedades agrícolas familiares, nas quais tem ocorrido aumento de áreas florestadas, muitas delas fragmentadas. O trabalho foi dividido em três partes: Análise das mudanças de uso e da cobertura da terra entre 1970 e 2005, identificando os principais indutores do aumento da cobertura florestal em uma região de ocorrência do muriqui-do-norte; Descrição do perfil socioeconômico, da percepção e das motivações dos proprietários rurais para a conservação de serviços ecossistêmicos; Proposição de corredores estruturais para sete populações de muriqui-do-norte, baseada na permeabilidade da matriz e na aceitação dos donos da terra. Foram utilizados mapas de uso e cobertura da terra, censos agropecuários, entrevistas semiestruturadas, métodos de valoração e compensação de serviços ambientais baseados no mercado de bens substitutos e na preferência declarada, além de simulações dos corredores ecológicos no programa LORACS. A decisão de deixar áreas naturais na propriedade rural é fortemente influenciada por fatores econômicos. O aumento da produtividade, possibilitada pela tecnificação agrícola, permitiu a ampliação da cobertura florestal no município de Santa Maria de Jetibá. O perfil socioeconômico dos agricultores entrevistados e as características das propriedades nos permitem inferir sobre a importância dos instrumentos políticos econômicos, do tipo de agricultura praticada e da percepção ambiental para criar oportunidades de conservação da biodiversidade. Programas de conservação que têm como meta a efetivação de corredores de vegetação em áreas privadas e, consequentemente, a perda de áreas produtivas, podem utilizar instrumentos políticos econômicos, baseados na disposição a receber, no custo de oportunidade da terra e no custo de restauração ecológica, para serem mais atrativos aos proprietários rurais, motivando-os a romper as barreiras para sua aceitação. / The changes imposed in land use and land cover, especially in forest areas, produce environmental changes at various levels. One negative consequence is the habitat fragmentation, followed by disturbance in many ecosystems, such as the loss of species and its populations. The study of factors influencing the increase of forest cover and its consequences for the conservation of biodiversity is essential for the planning of environmental policies, particularly for the regions where endangered species occur. One critical factor for the conservation of the spider monkeys (Brachyteles hypoxanthus) - a neotropical primate critically endangered, is the connectivity between remaining forest fragments, because necessary changes in land use and land cover will happen. The above mentioned conservation requires more integrated strategies than just the creation of protected areas, whereas the involvement of landowners and decision makers are needed. The use of economic policy instruments, such as compensation and payments for environmental services, can provide a strategy to encourage landowners to participate in biodiversity conservation programs on their lands. The present research consists in identifying the leading factors to the increase of forested areas on lands in family regime of exploitation and its consequences for biodiversity conservation. This study has been conducted in Santa Maria de Jetibá, a county of Espírito Santo, Brazil, where there are populations of spider monkeys inside little farms, whose forested areas have been increased, but fragmented. This work comprehends three parts: - Analysis of land use and land cover change between 1970 and 2005, identifying the main drivers of forest cover increase, in a region where spider monkeys occur; - Study of the socioeconomic profile, the perception and motivations of landowners for the conservation of ecosystem services; - Proposition of structural corridors for seven populations of spider monkeys, based on the matrix permeability and acceptance of landowners. The employed resources are: land cover maps, agricultural census, semi-structured interviews, and methods of valuation and compensation of environmental services based on the market of substitute goods and the declared preference, as well as simulations of ecological corridors in LORACS program. The decision to leave natural areas on the farm is strongly influenced by economic factors. The increase in productivity enabled by agricultural mechanization, allowed the expansion of forest cover in farms of Santa Maria de Jetibá. The socioeconomic profile of farmers and the characteristics of their properties prompted the influence of economic policy instruments, the type agriculture and the environmental conscience among farmers, to create biodiversity conservation opportunities. Conservation programs aiming to lay vegetation corridors in private land and, consequently, the loss of productive areas, can be implemented by economic policy instruments, based on the economical compensation, in the land opportunity cost and cost of ecological restoration, bring down barriers of landowners against conservational programs.
4

Connected Fragmented Habitats Facilitate Stable Coexistence Dynamics

Karsai, Istvan, Kampis, George 10 February 2011 (has links)
In this paper we endeavor to test the controversial ideas that exist about the role of fragmentation in a conservation context. In line with earlier understanding, we find that habitat fragmentation alone results in a strong detrimental effect (especially for the predator population). Connecting the fragmented habitats facilitates predator survival and hence prey survival as compared to the unconnected fragmented case. Our main result is counterintuitive: in the presence of a high quality predator, connected fragmented habitats ensure a better chance for coexistence than does even the unfragmented case. We explain why a connected fragmented habitat might thus be beneficial for the stabilization of the system, and how connections between sub-habitats are able to protect prey population from over-exploitation. In the model, habitat fragmentation is separated from the effects of habitat destruction, in order to better understand how populations react to habitat transformation.
5

Latinos and the Natural Environment Along the United States-Mexico Border

Lopez, Angelica 2011 December 1900 (has links)
The vitality of international transborder natural resources is important for the preservation of wildlife corridors, clean water, clean air, and working lands. In particular, not only does the Texas Rio Grande Valley Region in the United States (U.S.), on the U.S.-Mexico border, offer critical habitat important to North American migratory species, the area also provides substantial agricultural goods (i.e., sugarcane, sorghum, melons, onions, citrus, carrots, cabbage, and cattle). Hence, the dilemma between consumptive and non-consumptive uses of natural resources along a large geographic expanse separated by sociopolitical and sociocultural differences, is further complicated. Latinos of Mexican descent along the southwestern U.S. are one of the fastest growing ethnic groups in the U.S., yet their influence on U.S. natural resource allocation and management has been largely ignored. For this reason, the purpose of my study was threefold: (1) to determine public perceptions toward natural resources, the environment, and conservation; (2) to assess general environmental behaviors; and (3) to determine general recreational behaviors among three student population groups along the U.S.Mexico border region. The student groups were comprised of Texas students (Texas Latino and Texas non-Latino white), and Mexican students from three northern Mexico states, Chihuahua, Coahuila, and Tamaulipas. A survey was derived from three of the most frequently used environmental concern, behavior, and recreation indices used for research in the discipline. Predictors of environmental concern, behavior, and outdoor recreation participation for my sample varied across sociodemographic and sociopolitical variables for each student group. A review of environmental attitudes found Mexican students were more environmentally friendly (~ 2.35 odds; P < 0.05) than their U.S. counterparts. Among the three student groups, basic environmental behaviors (environmental conservation contribution; avoiding environmentally harmful products; changing car oil; and lawn responsibility) were influenced (P &lt; 0.05) by environmental orientation, political candidate's environmental position, father and mother's educational attainment, place of origin, sex, and combined parent income. Outdoor recreation participation and constraints to outdoor recreation participation among the student groups were influenced (P &lt; 0.05) by parent income, age, place of origin, and environmental orientation. Examples of constraints were: not enough money, personal health reasons, inadequate transportation, and personal safety reasons. Findings from my study benefit natural resource and environmental organizations pursuing collaborative program development and implementation along the U.S.-Mexico border and other transborder regions.
6

Nouvelle approche multispécifique intégrant les milieux aquatiques et terrestres pour l’évaluation de la connectivité du paysage

Lecours Tessier, Daphnée 09 1900 (has links)
La perte actuelle de biodiversité demande d’augmenter la superficie des territoires protégés, dans le but de réduire la perte d’habitat, leur fragmentation, et d’atténuer les impacts des changements climatiques. Cependant, un défi majeur demeure: quelles parties d'un paysage faut-il protéger ? Le potentiel de connectivité du paysage a été un des facteurs les plus utilisés dans les dernières années. Les méthodes actuelles d’estimation de connectivité présentent toutefois des lacunes non seulement quant au nombre d'espèces simulées, mais surtout quant à leur diversité taxonomique et fonctionnelle. Ici, j’améliore l'étude de la connectivité du paysage de trois manières: j’évalue le potentiel de connectivité du paysage en m’appuyant sur un modèle d’ensemble de 93 espèces, comprenant des espèces terrestres, aviaires et semi aquatiques; j’intègre les écosystèmes aquatiques et terrestres; enfin, j'utilise un modèle plus réaliste de déplacements d’espèces fauniques. Afin de développer la méthode, j’ai utilisé des données spatiales d’un territoire de la région des Laurentides au Québec qui présente un fort gradient anthropique, du sud (fortement urbanisé et agricole) au Nord (très peu urbanisé et largement forestier). J'ai analysé la connectivité du paysage pour les espèces fauniques en utilisant Omniscape. Ce programme permet des simulations omnidirectionnelles, lesquelles représentent mieux les mouvements des animaux; jusqu’à présent la majorité des évaluations de connectivité sont unidirectionnelles (déplacement du point A au point B). J’ai ensuite regroupé les résultats de simulations de dispersion par des analyses de regroupement (Fuzzy C-mean et Ward), obtenant trois groupes. Les résultats ont confirmé que la région délimitée par le Bouclier canadien contribue grandement aux déplacements des espèces terrestres et aquatiques alors que la région située dans les basses terres du Saint-Laurent y contribue très peu. Mes résultats soulignent également que les milieux aquatiques semblent jouer un rôle important pour la connectivité globale de la région des Laurentides, puisque plusieurs espèces (dont des espèces considérées « terrestres ») les utiliseraient pour se déplacer. Je soutiens donc qu'il est essentiel de mieux intégrer les habitats aquatiques et terrestres dans une compréhension holistique de la connectivité du paysage. / The present biodiversity loss required to increase the area of protected areas in order to reduce habitat loss, fragmentation, and mitigate the impacts of climate change. However, a major challenge remain: which parts of a landscape should be protected? The landscape connectivity potential has been one of the main factors used in recent years. However, current methods of estimating connectivity have shortcomings, not only in terms of the number of species simulated, but especially in terms of their taxonomic and functional diversity. Here, I improve the study of landscape connectivity in three ways: I assess the connectivity potential of the landscape based on a pool of 93 species, including terrestrial, avian and semi-aquatic species; I integrate aquatic and terrestrial ecosystems; and finally, I use a more realistic model of movements of wildlife species. In order to develop the method, I used spatial data from a territory in the Laurentides region of Quebec, which has a strong anthropogenic gradient from the South (highly urbanized and agricultural) to the North (very little urbanized and largely forested). I analyzed landscape connectivity for wildlife species using the program Omniscape. It allows omnidirectional simulations, which better represent the movements of animals; so far, the majority of connectivity assessments were unidirectional (from point A to point B). I then pooled the results of dispersion simulations by clustering analyzes (Fuzzy C-mean and Ward), which resulted in three groups. The results confirmed that the region delimited by the Canadian Shield contributes greatly to the movement of terrestrial and aquatic species, while the region located in the St. Lawrence Lowlands do not contribute that much. My results also underline that aquatic environments seem to play an important role in the overall connectivity of the Laurentian region, since several species (including species considered “terrestrial”) use them to move around. I therefore argue that it is essential to better integrate aquatic and terrestrial habitats into a holistic understanding of landscape connectivity.

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