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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.
71

Selling Protest in the News? Movement-Media Framing of Occupations: an Exploratory Study

Butz, Andrew David 31 July 2018 (has links)
Using quantitative content analysis, this study explores social movement (SM) framing in commercial news media -- by comparing how leading newspapers covered prominent protest occupations in 2011 and 2016. More than other SMs, anti-systemic protests like the 2011 Occupy Wall Street (OWS) and the 2016 Malheur Refuge Occupation (MRO) only have partial frame-setting agency, raising a broad theory question (to inform the research questions below): If SMs and media relate as interacting systems, are protest news frames more movement- or more media- driven; and do media not just enable but also constrain SMs? With the movement-media theory question above, the study design adapts media opportunity structure (MOS) to model a hierarchy of influences on news coverage of ideologically opposed or "distant twin" OWS and MRO, as 40- to 60-day protest occupations. The focused research question -- exploring media's constraining potential -- asks if commercial news framing of collective action: i) commercially frames or "sells" even anti-corporate protest; or ii) instead marginalizes or neutralizes such protest? Coverage from three top national or state newspapers (The New York Times, USA Today, and The Oregonian) was analyzed randomly from all protest stories during the occupations. Sampled time periods in 2011 and 2016, during actual encampments/ occupations in Portland, OR and New York City (OWS) and in Malheur National Wildlife Refuge, Oregon (MRO), also correspond with transitional years in print news. The inductive-based comparative results, from 15 coding dimensions for news framing of collective action, dispersed passivity, and commercially-framed activism, showed some evidence for the "selling protest" question. And the compiled summary Framing Advantages and Disadvantages yield this study's key finding: Although anti-corporate OWS was far larger, with more widespread media coverage, the comparative overall media frame for the small, remote, anti-government MRO was far more potent and resonant. Comparing media-and-movement framing of these distant twin 40-day protest occupations finds some support for the "selling (or underselling) protest" question. This comparative frame analysis helps bridge micro- and macro-theory levels, addressing an enduring dual gap in movement-media research literature -- to yield insight on SMs' and media's respective roles in protest news framing and then identify potential mechanisms for future research.
72

Mudanças do uso e cobertura do solo no refúgio da vida silvestre Banhado dos Pachecos e entorno

Neves, Daniel Duarte das January 2018 (has links)
As Unidades de Conservação (UC) são espaços territoriais com características naturais relevantes, que têm a função de assegurar a representatividade de amostras significativas e ecologicamente viáveis das diferentes populações, habitats e ecossistemas. A Legislação Brasileira instituiu no ano de 2000 o Sistema Nacional de Unidades de Conservação da Natureza (SNUC). Dentre os diversos ambientes encontrados em território nacional, o Pampa tem uma representatividade de apenas 0,4% de sua área protegida, conforme consta no SNUC. O Refúgio da Vida Silvestre Banhado dos Pachecos (RVSBP) é uma UC de proteção integral estadual, localizada no Rio Grande do Sul e no Bioma Pampa, com uma área de 2.560 ha e representa cerca de 3,5% de todas as UC’s de proteção integral desse bioma. O RVSBP criada no ano de 2002, e ainda não possui plano de manejo, bem como carece de maiores investimentos e atenção. O uso de imagens de satélites como subsídio aos estudos ambientais já está consolidado e a interpretação destas imagens, a partir de diversos métodos, para classificar o uso e cobertura da terra, tem se tornado uma constante, munindo os pesquisadores de informações dos diversos processos que possam estar ocorrendo em uma determinada área de estudo, inclusive monitorando as mudanças ao longo do tempo. Os objetivos desta dissertação são os de verificar as mudanças no uso e cobertura do solo ocorridas entre 2001 e 2017 no RVSBP e em seu entorno direto de 10km, baseando-se na análise de imagens de satélite. Para tanto serão mapeadas as classes de uso e cobertura do solo, a partir de imagens dos satélites LANDSAT 5 – Sensor TM, LANDSAT 7 – Sensor ETM+ e LANDSAT 8 – Sensor OLI, para os anos de 2001, 2009 e 2017. O método de detecção das mudanças no uso e cobertura do solo aplicada foi a técnica de comparação pós-classificação para uma melhor compreensão das interações entre os fenômenos naturais e as atividades humanas. Essa técnica foi aplicada para os períodos de 2001 a 2009, de 2009 a 2017 e de 2001 a 2017. Para o período de 2001 a 2009 as mudanças ocorreram em 17,5% da área de estudo e em 19,9% do RVSBP. Para o período de 2009 a 2017 as mudanças ocorreram em 22,8% da área de estudo e em 23,9% do RVSBP. Para o período de 2001 a 2017 as mudanças ocorreram em 24% da área de estudo e em 32% do RVSBP. Dentre esses 32% a classe que apresentou os maiores acréscimos de área foram as classes de Agricultura – Arroz e de Associação de Sítio e produtores rurais, que respectivamente compreendem áreas de 410 hectares e de 135 hectares. As classes que foram mais impactadas com perda de área foram as classes Banhado e Vegetação Arbórea, que respectivamente compreendem áreas de 435 hectares e de 173 hectares. A análise de detecção de mudanças se mostrou efetiva como uma forma de monitoramento sistemático do uso e cobertura do solo do RVSBP e entorno, trazendo elementos importantes para a gestão da UC. / Conservation Units (UC) are territorial spaces with relevant natural characteristics, which have a role of ensuring the representativeness of significant and ecologically viable samples of different populations, habitats and ecosystems. Brazilian legistlation established in 2000 the National System of Nature Conservation Units (SNUC). Among the several environments found in the national territory, the Pampa has a representation of only 0,4% of its own protected area, according to SNUC. The Wildlife Refuge Banhado dos Pachecos (RVSBP) is a state UC of integral protection, located in Rio Grande do Sul and Bioma Pampa, with 2.560 ha and comprises about 3,5% of all integral protection UC of this biome. RVSBP was created in 2002, still does not have a management plan, and lacks greater investments and attention. The use of satellite images to suppott environmental studies is already consolidate and the interpretation of these images, using different methods, to classify land and use cover, has become a constant, providing researchers with information on the various processes that may be occurring in a particular study area, including monitoring changes over time. The objective of this dissertation is to verify the changes in the land use and cover occurred between 2001 and 2017 in RVSBP and in its surrounds of 10km, based on the analysis of satellite images. Therefore, the land and use coverage classes were mapped using images from the LANDSAT 5 - Sensor TM, LANDSAT 7 - ETM + and LANDSAT 8 - OLI Sensor, for the years 2001, 2009 and 2017. The method of detecting changes in land use and cover was the post-classification comparison technique for a better understanding of the interactions between natural phenomena and human activities. This technique was applied for the periods from 2001 to 2009, from 2009 to 2017, and from 2001 to 2017. For the period 2001 to 2009 the changes occurred in 17,5% of the whole study area and in 19,9% of RVSBP. For the period from 2009 to 2017, changes occurred in 22,8% of the whole study area and 23,9% of RVSBP. For the period from 2001 to 2017, changes occurred in 24% of the whole study area and 32% of RVSBP. Among these 32%, the class with the greatest increases in area were Agriculture – Rice crops and Site Association of Rural Producers, which respectively comprises areas of 410 hectares and 135 hectares. The classes that were most impacted with loss of area were the class Weands and Arboreal Vegetation, which respectively comprise areas of 435 and 173 hectares. The change detection analysis was effective as a way of systematically monitoring the land use and coverage of RVSBP and surroundings, bringing important elements to the management of the UC.
73

Mudanças do uso e cobertura do solo no refúgio da vida silvestre Banhado dos Pachecos e entorno

Neves, Daniel Duarte das January 2018 (has links)
As Unidades de Conservação (UC) são espaços territoriais com características naturais relevantes, que têm a função de assegurar a representatividade de amostras significativas e ecologicamente viáveis das diferentes populações, habitats e ecossistemas. A Legislação Brasileira instituiu no ano de 2000 o Sistema Nacional de Unidades de Conservação da Natureza (SNUC). Dentre os diversos ambientes encontrados em território nacional, o Pampa tem uma representatividade de apenas 0,4% de sua área protegida, conforme consta no SNUC. O Refúgio da Vida Silvestre Banhado dos Pachecos (RVSBP) é uma UC de proteção integral estadual, localizada no Rio Grande do Sul e no Bioma Pampa, com uma área de 2.560 ha e representa cerca de 3,5% de todas as UC’s de proteção integral desse bioma. O RVSBP criada no ano de 2002, e ainda não possui plano de manejo, bem como carece de maiores investimentos e atenção. O uso de imagens de satélites como subsídio aos estudos ambientais já está consolidado e a interpretação destas imagens, a partir de diversos métodos, para classificar o uso e cobertura da terra, tem se tornado uma constante, munindo os pesquisadores de informações dos diversos processos que possam estar ocorrendo em uma determinada área de estudo, inclusive monitorando as mudanças ao longo do tempo. Os objetivos desta dissertação são os de verificar as mudanças no uso e cobertura do solo ocorridas entre 2001 e 2017 no RVSBP e em seu entorno direto de 10km, baseando-se na análise de imagens de satélite. Para tanto serão mapeadas as classes de uso e cobertura do solo, a partir de imagens dos satélites LANDSAT 5 – Sensor TM, LANDSAT 7 – Sensor ETM+ e LANDSAT 8 – Sensor OLI, para os anos de 2001, 2009 e 2017. O método de detecção das mudanças no uso e cobertura do solo aplicada foi a técnica de comparação pós-classificação para uma melhor compreensão das interações entre os fenômenos naturais e as atividades humanas. Essa técnica foi aplicada para os períodos de 2001 a 2009, de 2009 a 2017 e de 2001 a 2017. Para o período de 2001 a 2009 as mudanças ocorreram em 17,5% da área de estudo e em 19,9% do RVSBP. Para o período de 2009 a 2017 as mudanças ocorreram em 22,8% da área de estudo e em 23,9% do RVSBP. Para o período de 2001 a 2017 as mudanças ocorreram em 24% da área de estudo e em 32% do RVSBP. Dentre esses 32% a classe que apresentou os maiores acréscimos de área foram as classes de Agricultura – Arroz e de Associação de Sítio e produtores rurais, que respectivamente compreendem áreas de 410 hectares e de 135 hectares. As classes que foram mais impactadas com perda de área foram as classes Banhado e Vegetação Arbórea, que respectivamente compreendem áreas de 435 hectares e de 173 hectares. A análise de detecção de mudanças se mostrou efetiva como uma forma de monitoramento sistemático do uso e cobertura do solo do RVSBP e entorno, trazendo elementos importantes para a gestão da UC. / Conservation Units (UC) are territorial spaces with relevant natural characteristics, which have a role of ensuring the representativeness of significant and ecologically viable samples of different populations, habitats and ecosystems. Brazilian legistlation established in 2000 the National System of Nature Conservation Units (SNUC). Among the several environments found in the national territory, the Pampa has a representation of only 0,4% of its own protected area, according to SNUC. The Wildlife Refuge Banhado dos Pachecos (RVSBP) is a state UC of integral protection, located in Rio Grande do Sul and Bioma Pampa, with 2.560 ha and comprises about 3,5% of all integral protection UC of this biome. RVSBP was created in 2002, still does not have a management plan, and lacks greater investments and attention. The use of satellite images to suppott environmental studies is already consolidate and the interpretation of these images, using different methods, to classify land and use cover, has become a constant, providing researchers with information on the various processes that may be occurring in a particular study area, including monitoring changes over time. The objective of this dissertation is to verify the changes in the land use and cover occurred between 2001 and 2017 in RVSBP and in its surrounds of 10km, based on the analysis of satellite images. Therefore, the land and use coverage classes were mapped using images from the LANDSAT 5 - Sensor TM, LANDSAT 7 - ETM + and LANDSAT 8 - OLI Sensor, for the years 2001, 2009 and 2017. The method of detecting changes in land use and cover was the post-classification comparison technique for a better understanding of the interactions between natural phenomena and human activities. This technique was applied for the periods from 2001 to 2009, from 2009 to 2017, and from 2001 to 2017. For the period 2001 to 2009 the changes occurred in 17,5% of the whole study area and in 19,9% of RVSBP. For the period from 2009 to 2017, changes occurred in 22,8% of the whole study area and 23,9% of RVSBP. For the period from 2001 to 2017, changes occurred in 24% of the whole study area and 32% of RVSBP. Among these 32%, the class with the greatest increases in area were Agriculture – Rice crops and Site Association of Rural Producers, which respectively comprises areas of 410 hectares and 135 hectares. The classes that were most impacted with loss of area were the class Weands and Arboreal Vegetation, which respectively comprise areas of 435 and 173 hectares. The change detection analysis was effective as a way of systematically monitoring the land use and coverage of RVSBP and surroundings, bringing important elements to the management of the UC.
74

A efetividade do Refúgio de Vida Silvestre Veredas do Oeste Baiano frente ao avanço da fronteira agrícola MATOPIBA / The effectiveness of the Veredas of Western Bahia Wildlife Refuge facing of the advance of the agricultural frontier MATOPIBA

Pôssas, Isabela Braichi 02 October 2017 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2017-11-21T10:46:39Z No. of bitstreams: 2 Dissertação - Isabela Braichi Pôssas - 2017.pdf: 13998722 bytes, checksum: 0888f201356fb6d0215b929b420cfac1 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-11-21T10:47:10Z (GMT) No. of bitstreams: 2 Dissertação - Isabela Braichi Pôssas - 2017.pdf: 13998722 bytes, checksum: 0888f201356fb6d0215b929b420cfac1 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-11-21T10:47:10Z (GMT). No. of bitstreams: 2 Dissertação - Isabela Braichi Pôssas - 2017.pdf: 13998722 bytes, checksum: 0888f201356fb6d0215b929b420cfac1 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-10-02 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The protection of natural resources by the creation of Protected Areas (PAs) has been implemented in Brazil with relative success, allowing a significant diversity of framing between integral protection and sustainable use. The effectiveness of these protected areas is determined by the social actors involved in the unit and its surroundings. Only in the Cerrado, there are 386 protected areas covering the entire biome in different socio-economic and environmental contexts. The northern portion of this biome is under intense pressure for the intensification of the conversion of the Cerrado by agribusiness, which has been enhanced since the creation of the MATOPIBA region. In the western Bahia Plateau, this expansion has been specifically polarized by the municipalities of Luiz Eduardo Magalhães and Barreiras, and has been intensified in the last 15 years with the consolidation of irrigation projects by central pivots. In 2000, the federal government created the Refugio de Vida Silvestre Veredas do Oeste Baiano (RVSVOB) in this region to fully protect a habitat of the loon duck (Mergus octosetaceus). Its geographic boundaries follow roughly the layout of the enclosed valley of the Pratudinho River and the high valley of the Pratudão River, including, at its extreme east, a part of dissected hills. Despite being protected, the area and its ecological function have suffered from the impacts of anthropogenic pressures from the plateaus (exploitation of water for the projects and central-pivot installation, e.g.) and in the enclosed valleys (burnings, grazing, accelerated erosion, e.g.). Due to these problems and the strict relation that the UC has with the superficial water resources, the effectiveness of the RVSVOB can be put in checkmate. In this context, it is proposed to evaluate the effectiveness of this PA through of the analysis and modeling of analogous space-time environmental systems. Therefore, the adjacent watersheds were chosen in the north - Veredãozinho River - and in the south - the Formoso River - whereas similar areas to the RVSVOB were delineated for comparative analysis of the most important elements and flows in the ecological function of this PA. The analysis units adopted were: (i) watershed, (ii) watershed segments (high, medium and low), (iii) RVSVOB and its similar areas. The elements and flows analyzed were (i) change of land use and cover, (ii) installation of central pivots, (iii) river channel flow, (iv) physical and chemical aspects of canal water fluvial. The river waters were sampled twice (end of rainy and dry seasons) in three points along each channel (Rios Veredãozinho, Pratudinho and Formoso) in the hydrological year 2015-2016. The elements related to land use were obtained by the interpretation of maps generated by a time series classification (1970, 1980, 1990, 2000, 2010 and 2016) satellite images from Landsat (5, 7 and 8) and the other data obtained from public agencies. The results indicate that, in general, the three basins are inserted in the same context of succession of use and land cover, following the trend of what happens around the Chapada do Oeste Baiano. In the 1970s, 1980s and 1990s, the savanna formation burned for the pioneer occupation of livestock and forestry, while agriculture still occupied small stretches of the valleys. From 2000 on, the area of agriculture grows exponentially and gains space over areas of forestry and savanna formations and abandons the valleys. Specifically, RVSVOB and its analogous areas have similar succession of cover and land use up to the creation of the PA in 2000, when, in the PA, the burnings and agriculture start to reduce exponentially. The installation of central pivots and the concession of water grants were also heterogeneous among the three analyzed basins, with a higher concentration in the upper and lower sectoin of the Formoso River basin and in the lower section of the Pratudinho River. The quality and quantity of water in the three sampling points in each basin do not have any significant difference in the measured values, showing, in general, low concentration of suspended load and turbidity and high dissolved oxygen. The evaluation of the effectiveness of RVSVOB allows verifying that, on the one hand, the unit has contributed to the conservation of the Cerrado within its territory - recovering deforested and burned areas and, on the other hand, the quality and quantity of water resources is independent of the existence of RVSVOB, being similar in the nine monitored stretches. This similarity allows affirming that the quality of the water resources is good in all points, however, the lack of flow data prior to the superficial and underground grants does not allow evaluating if there is loss in the amount of water in the channels. This framework shows that, on the one hand, the Refugio de Vida Silvestre Veredas do Oeste Baiano has fulfilled its ecological function, ensuring the quality of natural resources, on the other, the expansion of agribusiness occupies preferably the areas of the highlands and plateaus not pressing the dynamic of enclosed valleys but indirectly. / A proteção dos recursos naturais pela criação de unidades de conservação (UCs) tem sido implementada no Brasil com relativo sucesso, permitindo uma diversidade significativa de enquadramentos de áreas entre proteção integral e uso sustentável. A efetividade dessas UCs é determinada pelos atores sociais envolvidos na unidade e em seu entorno. Só no Cerrado, existem 386 unidades de conservação que recobrem todo o bioma em diferentes contextos sócio-econômico-ambientais. Destacadamente, a porção setentrional desse bioma está sob franca pressão pela intensificação da conversão do Cerrado pelo agronegócio, o que é potencializado desde a criação da região do MATOPIBA. Na Chapada do Oeste Baiano, essa expansão tem sido polarizada, especificamente, pelos municípios de Luiz Eduardo Magalhães e Barreiras, e foi intensificada nos últimos 15 anos com a consolidação dos projetos de irrigação por pivôs centrais. Em 2000, o governo federal criou o Refúgio da Vida Silvestre Veredas do Oeste Baiano (RVSVOB) nessa região para proteger, integralmente, um habitat do pato mergulhão (Mergus octosetaceus). Seus limites geográficos seguem, grosso modo, o traçado do vale encaixado do Rio Pratudinho e do alto vale do Rio Pratudão, incluindo, em seu extremo leste, uma parte de colinas dissecadas. Apesar de ser protegida, a área e sua função ecológica vem sofrendo com os impactos causados pelas pressões antrópicas da ocupação das chapadas (explotação de água para os projetos e instalação pivôs centrais, e.g.) e própria aos vales encaixados (queimadas, pastoreio, erosão acelerada, e.g.). Por esses problemas e pela estrita relação que a UC tem com os recursos hídricos superficiais, a efetividade da RVSVOB pode ser colocada em xeque. Nesse contexto, propõe-se avaliar a efetividade dessa UC por meio da análise e modelagem de sistemas ambientais análogos espaço-temporais. Para tanto, foram escolhidas as bacias hidrográficas adjacentes, a norte, do Rio Veredãozinho, e, a sul, do Rio Formoso, onde foram delimitadas áreas análogas a RVSVOB para análises comparativas dos elementos e fluxos mais importantes na função ecológica da RVSVOB. As unidades de análise adotadas foram: (i) bacia hidrográfica, (ii) trechos de bacia hidrográfica (alta, média e baixa), (iii) RVSVOB e áreas análogas. Os elementos e fluxos analisados foram: (i) mudança do uso e cobertura do solo, (ii) instalação de pivôs centrais, (iii) vazão do canal fluvial, (iv) aspectos físico-químicos da água do canal fluvial. As águas fluviais foram amostradas duas vezes. Os elementos relacionados ao uso do solo foram obtidos pela interpretação de mapas gerados pela classificação de uma série histórica (1970 a 2016) de imagens de satélite LANDSAT (1, 5 e 8) e os demais dados foram obtidos junto a órgãos públicos. Os resultados indicam que, em geral, as três bacias estão inseridas em um mesmo contexto de sucessão de uso e cobertura do solo, seguindo a tendência daquilo que acontece em todo a Chapada do Oeste Baiano. Em 1970 a 1990, predominou a queimada da formação savânica para a ocupação pioneira de pecuária e silvicultura, quando a agricultura ainda ocupava pequenos trechos dos vales. A partir de 2000, a área de agricultura cresce exponencialmente e ganha espaço sobre áreas de silvicultura e de formações savânicas e abandona os vales. Especificamente, a RVSVOB e suas áreas análogas tem sucessão de cobertura e uso do solo semelhantes até a criação da UC em 2000, a partir de quando, na UC, as queimadas e a agricultura passam a reduzir exponencialmente. A instalação de pivôs centrais e outorgas de água também foram heterogêneas entre as três bacias analisadas, tendo maior concentração no alto e médio trecho bacia do Rio Formoso e no baixo trecho do Rio Pratudinho. A qualidade e quantidade de água nos três pontos amostrados em cada bacia não tem nenhuma diferença significativa nos valores mensurados, tendo, em geral, baixa concentração de carga em suspensão e turbidez e elevado oxigênio dissolvido. A avaliação da efetividade da RVSVOB pelo método adotado permite constatar que, por um lado, a unidade tem contribuído para a conservação do Cerrado dentro de seu território – recuperando áreas desmatadas e queimadas – e, por outro lado, a qualidade e quantidade dos recursos hídricos independe da existência da RVSVOB, sendo similar nos nove trechos monitorados. Essa similaridade permite afirmar que a qualidade dos recursos hídricos é boa em todos os pontos, por outro lado, a inexistência de dados de vazão anteriores às captações superficiais e subterrâneas não permite avaliar se há perda na quantidade de água nos canais. Esse quadro permite concluir que, se por um lado, o RVSVOB tem cumprido sua função ecológica, garantindo a qualidade dos recursos naturais, por outro, a expansão do agronegócio ocupa, preferencialmente, as áreas das chapadas e platôs, não pressionando a dinâmica os vales encaixados diretamente, mas sim indiretamente.
75

Use of Water Indices Derived from Landsat OLI Imagery and GIS to Estimate the Hydrologic Connectivity of Wetlands in the Tualatin River National Wildlife Refuge

Blackmore, Debra Sue 30 August 2016 (has links)
This study compared two remote sensing water indices: the Normalized Difference Water Index (NDWI) and the Modified NDWI (MNDWI). Both indices were calculated using publically-available data from the Landsat 8 Operational Land Imager (OLI). The research goal was to determine whether the indices are effective in locating open water and measuring surface soil moisture. To demonstrate the application of water indices, analysis was conducted for freshwater wetlands in the Tualatin River Basin in northwestern Oregon to estimate hydrologic connectivity and hydrological permanence between these wetlands and nearby water bodies. Remote sensing techniques have been used to study wetlands in recent decades; however, scientific studies have rarely addressed hydrologic connectivity and hydrologic permanence, in spite of the documented importance of these properties. Research steps were designed to be straightforward for easy repeatability: 1) locate sample sites, 2) predict wetness with water indices, 3) estimate wetness with soil samples from the field, 4) validate the index predictions against the soil samples from the field, and 5) in the demonstration step, estimate hydrologic connectivity and hydrological permanence. Results indicate that both indices predicted the presence of large, open water features with clarity; that dry conditions were predicted by MNDWI with more subtle differentiation; and that NDWI results seem more sensitive to sites with vegetation. Use of this low-cost method to discover patterns of surface moisture in the landscape could directly improve the ability to manage wetland environments.
76

A Study on Residents' Perceptions and Attitudes Towards the Vieques National Wildlife Refuge in Puerto Rico

Guzman, Ana C 31 March 2016 (has links)
Conflicts between local people and protected areas can undermine conservation goals. This study explores perceptions towards Vieques National Wildlife Refuge (VNWR), a complex former military site containing a combination of high ecological value along with an array of unexploded ordnances. The purpose of this research is to evaluate how residents perceive VNWR and elucidate conflicts associated with former and current uses of the wildlife refuge. Here, I interviewed 235 residents of Vieques Island, Puerto Rico using semi-structured surveys and 33 key informants representing various stakeholder groups to assess attitudes toward VNWR. A combination of factors influencing attitudes about VNWR included socio-economic status and misconceptions about management. Overall, residents did not express strong attitudes. However, older individuals and those living longer on Vieques generally had poorer attitudes than others. Among the most common reasons for expressing discontent were the restrictive regulations regarding access to VNWR and the limitations on resource extraction.
77

Mudanças do uso e cobertura do solo no refúgio da vida silvestre Banhado dos Pachecos e entorno

Neves, Daniel Duarte das January 2018 (has links)
As Unidades de Conservação (UC) são espaços territoriais com características naturais relevantes, que têm a função de assegurar a representatividade de amostras significativas e ecologicamente viáveis das diferentes populações, habitats e ecossistemas. A Legislação Brasileira instituiu no ano de 2000 o Sistema Nacional de Unidades de Conservação da Natureza (SNUC). Dentre os diversos ambientes encontrados em território nacional, o Pampa tem uma representatividade de apenas 0,4% de sua área protegida, conforme consta no SNUC. O Refúgio da Vida Silvestre Banhado dos Pachecos (RVSBP) é uma UC de proteção integral estadual, localizada no Rio Grande do Sul e no Bioma Pampa, com uma área de 2.560 ha e representa cerca de 3,5% de todas as UC’s de proteção integral desse bioma. O RVSBP criada no ano de 2002, e ainda não possui plano de manejo, bem como carece de maiores investimentos e atenção. O uso de imagens de satélites como subsídio aos estudos ambientais já está consolidado e a interpretação destas imagens, a partir de diversos métodos, para classificar o uso e cobertura da terra, tem se tornado uma constante, munindo os pesquisadores de informações dos diversos processos que possam estar ocorrendo em uma determinada área de estudo, inclusive monitorando as mudanças ao longo do tempo. Os objetivos desta dissertação são os de verificar as mudanças no uso e cobertura do solo ocorridas entre 2001 e 2017 no RVSBP e em seu entorno direto de 10km, baseando-se na análise de imagens de satélite. Para tanto serão mapeadas as classes de uso e cobertura do solo, a partir de imagens dos satélites LANDSAT 5 – Sensor TM, LANDSAT 7 – Sensor ETM+ e LANDSAT 8 – Sensor OLI, para os anos de 2001, 2009 e 2017. O método de detecção das mudanças no uso e cobertura do solo aplicada foi a técnica de comparação pós-classificação para uma melhor compreensão das interações entre os fenômenos naturais e as atividades humanas. Essa técnica foi aplicada para os períodos de 2001 a 2009, de 2009 a 2017 e de 2001 a 2017. Para o período de 2001 a 2009 as mudanças ocorreram em 17,5% da área de estudo e em 19,9% do RVSBP. Para o período de 2009 a 2017 as mudanças ocorreram em 22,8% da área de estudo e em 23,9% do RVSBP. Para o período de 2001 a 2017 as mudanças ocorreram em 24% da área de estudo e em 32% do RVSBP. Dentre esses 32% a classe que apresentou os maiores acréscimos de área foram as classes de Agricultura – Arroz e de Associação de Sítio e produtores rurais, que respectivamente compreendem áreas de 410 hectares e de 135 hectares. As classes que foram mais impactadas com perda de área foram as classes Banhado e Vegetação Arbórea, que respectivamente compreendem áreas de 435 hectares e de 173 hectares. A análise de detecção de mudanças se mostrou efetiva como uma forma de monitoramento sistemático do uso e cobertura do solo do RVSBP e entorno, trazendo elementos importantes para a gestão da UC. / Conservation Units (UC) are territorial spaces with relevant natural characteristics, which have a role of ensuring the representativeness of significant and ecologically viable samples of different populations, habitats and ecosystems. Brazilian legistlation established in 2000 the National System of Nature Conservation Units (SNUC). Among the several environments found in the national territory, the Pampa has a representation of only 0,4% of its own protected area, according to SNUC. The Wildlife Refuge Banhado dos Pachecos (RVSBP) is a state UC of integral protection, located in Rio Grande do Sul and Bioma Pampa, with 2.560 ha and comprises about 3,5% of all integral protection UC of this biome. RVSBP was created in 2002, still does not have a management plan, and lacks greater investments and attention. The use of satellite images to suppott environmental studies is already consolidate and the interpretation of these images, using different methods, to classify land and use cover, has become a constant, providing researchers with information on the various processes that may be occurring in a particular study area, including monitoring changes over time. The objective of this dissertation is to verify the changes in the land use and cover occurred between 2001 and 2017 in RVSBP and in its surrounds of 10km, based on the analysis of satellite images. Therefore, the land and use coverage classes were mapped using images from the LANDSAT 5 - Sensor TM, LANDSAT 7 - ETM + and LANDSAT 8 - OLI Sensor, for the years 2001, 2009 and 2017. The method of detecting changes in land use and cover was the post-classification comparison technique for a better understanding of the interactions between natural phenomena and human activities. This technique was applied for the periods from 2001 to 2009, from 2009 to 2017, and from 2001 to 2017. For the period 2001 to 2009 the changes occurred in 17,5% of the whole study area and in 19,9% of RVSBP. For the period from 2009 to 2017, changes occurred in 22,8% of the whole study area and 23,9% of RVSBP. For the period from 2001 to 2017, changes occurred in 24% of the whole study area and 32% of RVSBP. Among these 32%, the class with the greatest increases in area were Agriculture – Rice crops and Site Association of Rural Producers, which respectively comprises areas of 410 hectares and 135 hectares. The classes that were most impacted with loss of area were the class Weands and Arboreal Vegetation, which respectively comprise areas of 435 and 173 hectares. The change detection analysis was effective as a way of systematically monitoring the land use and coverage of RVSBP and surroundings, bringing important elements to the management of the UC.
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A four-pronged approach to addressing a wild pig invasion in a bottomland and upland forested landscape

Evans, Tyler Scott 08 August 2023 (has links) (PDF)
Among exotic species that are capable of invading, establishing, and reaching pest status, few pose the range of impacts to biotic (e.g., competition with native species, predation, herbivory, introduction of other exotics) and abiotic (e.g., soil, hydrology) ecosystem components that can be attributed to the wild pig (Sus scrofa). Despite the presence of wild pigs throughout the southeastern United States for centuries, new invasions continue to occur in previously uninhabited and often under-investigated landscapes, including bottomland and upland forests. The recent invasion of the Sam D. Hamilton Noxubee National Wildlife Refuge (hereafter, NNWR) in east-central Mississippi represents an opportunity to understand not only a species invasion during an emergent stage, but also to improve and better inform the methods used to combat such species in forested landscapes. In recent years, the United States Fish and Wildlife Service has begun to observe direct impacts to this ecologically sensitive area which is critically important to not only migratory waterfowl but also a multitude of other faunal (e.g., amphibians, reptiles, and avian species of concern) and floral species. As a result, identifying wild pig spatial distributions (e.g., movements, occurrence) and estimating wild pig abundance in the NNWR have each increased in priority. My dissertation research has facilitated an improved understanding of how wild pigs have invaded this novel landscape through investigations of space use, abundance, and occurrence, and will better inform and improve efficiency of future monitoring and control efforts. Understanding how this wild pig invasion relates to the NNWR landscape may also provide information that can be used to better address wild pig invasions of similar landscapes, with added value for those that are similarly characterized by sensitive ecosystems (i.e., managed for migratory waterfowl, species of concern) that are currently faced with this emerging threat. Given the universality of many of the methodological approaches undertaken in this effort, this multifaceted investigation also provides broader implications for other landscapes and exotic species of interest.
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Habitat Selection and Nesting Ecology of Snowy Plover in the Great Basin

Ellis, Kristen Sue 26 November 2013 (has links) (PDF)
Snowy plovers (Charadrius nivosus) are small, ground-nesting shorebirds that are a species of conservation concern throughout North America. Despite increased efforts to understand factors contributing to the decline of snowy plover, little is known about habitat selection and breeding ecology of snowy plover for the large population found in the Great Basin. We tested hypotheses concerning the occupancy and nesting success of snowy plover. First, we identified factors influencing snowy plover nest survival at Great Salt Lake, Utah. We hypothesized that snowy plover would demonstrate differences in nest survival rates across years due to differences in habitat characteristics, predator abundance, human influence, resource availability, and fluctuating water levels. We conducted nest surveys at five sites along the Great Salt Lake to locate new nests or monitor known nests until nest fate was determined. We found 608 nests between 2003, 2005-2010, and 2012. The most common cause of nest failure was predation, followed by weather, abandonment, and trampling. Nest survival estimates ranged from 4.6 -- 46.4% with considerable yearly variation. There was no correlation between researcher activity (visits to nests and trapping of adults) and nest survival. Nests in close proximity to roads had lower survival than nests far from roads. Nests located on barren mudflats also had lower survival than nests in vegetated areas or near debris. We found that nests had a higher probability of survival as they increased in incubation stage. Because nesting areas around the Great Salt Lake host some of the largest concentrations of breeding snowy plover in North America, we suggest that managers consider measures to maintain suitable nesting habitat for snowy plover. Second, we determined factors affecting snowy plover occupancy and detection probabilities in western Utah between 2011 and 2012. We hypothesized that snowy plover would be associated with spring water flows and sparsely vegetated salt flats. We made repeated visits to randomly selected survey plots recording the number of snowy plover adults and habitat characteristics within each plot. We modeled the relationship between snowy plover detection probability and habitat and environmental characteristics. The detection probability was 77% (95% CI = 64 -- 86%) and did not vary by year. There was a positive relationship between ambient temperature and detection probability. Next, we modeled the relationship between snowy plover occupancy and individual habitat characteristics including distance to water, distance to roads, land cover types, and vegetative characteristics. Snowy plover occupancy did not vary by year and was estimated at 12% (95% CI = 7 -- 21%). Occupancy was best predicted by close proximity to water, playa land cover, and minimal shrub cover. We used habitat characteristics that best predicted snowy plover occupancy to generate a predictive habitat model that can help prioritize future snowy plover surveys and guide conservation efforts.
80

Practicing Conservation Biology at Back Bay National Wildlife Refuge

Stone, Lindsey Fay 09 January 2014 (has links)
No description available.

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