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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.
411

Consequences of nitrogen fertilization and soil acidification from acid rain on dissolved carbon and nitrogen stability in the unglaciated Appalachian Mountains

Taylor, Philip Graham 05 September 2008 (has links)
The expansion and proliferation of reactive nitrogen (N) sources, predominantly fertilizer application and fossil fuel combustion, has enriched the earth with N and acidified ecosystems. Acid rain is a primary vector of both N fertilization and acidification, initiating a cascade of consequences that alter biogeochemical cycling and global biological structure and function. Studies on N and acid influences are however rarely linked despite their common source. We used a wide, chronic gradient of N deposition (5.5 – 31 kg N ha⁻¹ yr-1) to explore patterns in carbon (C) and N cycling in light of recognized biogeochemical responses to acidic deposition. Specifically, we examined the response of key controls on dissolved C and N stability because soluble pools are involved in decomposition and nutrient recycling, the formation of soil organic matter (SOM), and the translation of elements through the biogeochemical continuum from atmospheric to soil to water. Results suggest that N deposition led to reduced organic matter C/N, enhanced net nitrification, and greater DON generation; and, these patterns were associated with changes in C composition. Conversely, physiochemical processes in the mineral soil seemed to control organic matter dynamics, with effects on N processing. Moreover, pH dependent controls on DOC stability were evidenced by changes in DOC concentration, chemical complexity and recalcitrance. These horizon-specific, differential responses to acid rain indicate that changes in the forest floor N economy were responsible for increased surface water NO3-N concentrations, whereas enhanced organomineral stability of DOC caused a significant increase in DOM concentrations in export. / Master of Science
412

What's in Your Garden? Assessing the "Eco-friendliness" of Plant Choices of Denton, Texas Gardeners

Cloutier, Andrea Nicole 12 1900 (has links)
Urbanization is seen as a threat to biodiversity within urban ecosystems, which are largely reliant on humans for their composition. Two types of extremes exist in the spectrum of urban domestic gardens; on one end, the typical urban garden which is planted by landscapers at the time the house is built and is generally left unchanged, and, at the other, a "wild" landscape planted entirely with native plants which provides habitat for native fauna and pollinators. This study assesses the plant choices made by members of organized gardening groups-the Denton County Master Gardeners (DCMG), the Elm Fork Master Naturalists (EFMN), the Trinity Forks Native Plant Society (TFNPS), and Keep Denton Beautiful (KDB)-and toward which extreme these choices put these gardens on the psectrum. TFNPS and EFMN both fall closer to the wild garden extreme, with TFNPS the closest to a "wild garden." DCMG was almost directly between the two extremes, but fell closer to the typical urban garden. By looking at how these groups manage their gardens, we begin to understand the ways in which gardeners can mitigate and soften the harsh changes between wild landscapes and urban environments. Collaboration between groups could have the potential to encourage more people to use native plants which provide habitat for native fauna and pollinators if those in the typical urban garden spectrum could find in the "wild" gardens of those on the opposite end of the spectrum.
413

Influence of the Mexican prairie dog (Cynomys mexicanus) on plant taxonomical and functional diversity and soil properties in semiarid grasslands of Mexico

Rodriguez Barrera, Maria Gabriela 08 August 2024 (has links)
Research in grassland ecosystems worldwide has highlighted the crucial role many burrowing herbivore mammals provide as so-called “ecosystem engineers”. Many of these examples come from North America and have mostly been focused on Prairie Dogs (Cynomys sp.), which, due to their burrowing and grazing activities, are considered as a species of high ecological importance. Multiple studies have shown that their loss reduces grassland ecosystem functions and that their activities increase plant, arthropod, bird and mammal biodiversity, grassland heterogeneity, provide benefits to cattle, among many other key ecological roles. However, prairie dog species are distributed throughout multiple landscapes in North America, and most of the studies have been on mixed prairie grasslands. It is therefore not surprising that, when comparing the effects of different prairie dog species across ecoregions, the role of prairie dogs is not as clear and results vary, depending on spatial context, type of grasslands, climate and environmental conditions. Yet, grasslands are considered as some of the most highly threatened ecosystems, having high rates of conversion, desertification and biodiversity loss. Therefore, it is imperative to understand the effects prairie dog species have on the ecosystem. In this thesis, I focus on the Mexican prairie dog (C. mexicanus), a species in drastic decline due to habitat loss, caused by agriculture, overgrazing, human settlement, fragmentation, diseases (e.g. plague) and past eradication programs. C. mexicanus is considered endangered by the IUCN red list of threatened species and The Convention of International Trade in Endangered Species of Wild Fauna and Flora. It is also endemic to the Grassland Priority Conservation Area (GPCA) of El Tokio, located in Northeast Mexico within the Chihuahuan desert ecoregion and designated as a GPCA by the Commission for Environmental Cooperation (a cooperation between Canada, U.S. and Mexico) in 2009. Grasslands within GPCA El Tokio are highly fragmented as a result of many years of intense agricultural practices and other anthropogenic activities and around 90% of the original grasslands have been lost. However, it is considered an area of ecological importance due to its unique vegetation and edaphic associations, as well as being a key habitat for migratory birds. Up until now, very few studies have explored the role C. mexicanus has on plant taxonomical diversity and soil properties. Moreover, no studies focusing on prairie dogs have looked into the effect the species has on plant functional diversity or soil properties. Furthermore, GPCA El Tokio is a data-scarce area. Therefore, at this point, basic information and system understanding are urgently needed in order to identify which conservation efforts are most promising and which specific sites these efforts should focus on. Understanding the influence of prairie dog disturbance on vegetation parameters (taxonomic and functional), soil properties and their interaction with environmental conditions through time, will increase knowledge on the risks and vulnerability of grasslands, promoting solutions that can support grassland management. Furthermore, there is a clear gap in the literature about the varying effects of prairie dogs depending on different grassland types and environmental conditions. To study such conditions, I first classified and controlled for factors that could influence prairie dog ecosystem engineering effects addressing the following two general questions: (1) Which grassland types are present in GPCA El Tokio? (2) Do the different grassland types present in GPCA El Tokio influence prairie dog colony sizes and burrow density? When influencing factors were confirmed, I then assess the effects of prairie dog disturbance on vegetation and soil to answer the following questions: (3) Are there clear distinctions across GPCA El Tokio grassland environmental variables? (4) Do the different grassland types present in GPCA El Tokio influence prairie dog colony sizes and burrow density? To do so I selected a representative sample of sites covering the varying environmental conditions present in GPCA El Tokio grasslands, a data-driven clustering approach was used. Once clusters were defined, average burrow density was estimated from remote sensing imagery. To study vegetation measures I first, sampled plant species (92 species and 28 families and 6 traits) to obtain taxonomical and functional diversity measures, and obtained variables related to nutrient availability, carbon and climate regulation, and water regulation and purification. To study the effects on soil a total of 11 soil properties were obtained (382 samples were analyzed). Field work was done during the wet season and repeated during the dry season to obtain season variations of all measures. Soil measures were further obtained at depths of 0-10cm and 10 to 20cm. Results from the study classify GPCA El Tokio into 8 different grassland types with 4 clusters being the most dominant, named Agriculture, Arid, Calcareous, Mountain. I found agricultural grasslands had significantly lower colony sizes compared to calcareous grasslands when outliers were considered, but no differences when outliers were removed and burrow density varied depending on the grassland type, with mountain grasslands having a significantly lower burrow density compared to agricultural and calcareous grasslands. Regarding the effects of prairie dogs on vegetation and soil my findings suggest that functional metrics and community weighted mean (CWM) analyses responded to interactions between prairie dog disturbance, grassland type and season, whilst species diversity and cover measures were less sensitive to the role of prairie dog disturbance. I found weak evidence that prairie dog disturbance has a negative effect on vegetation structure, except for minimal effects on C4 and graminoid cover, but which depended mainly on season. Grassland type and season explained most of the effects on plant functional and taxonomic diversity as well as CWM traits. In the case of soil properties WOP grasslands tended to have higher nutrient availability than WP grasslands. However, mounds played a key role within WP grasslands. Mounds reduce compaction and increase nutrient levels of soil organic carbon, nitrogen, potassium, magnesium, and phosphorus. Such an effect was particularly present in calcareous and arid grasslands, and in many cases the effect was enhanced under wet conditions. In general, the effect of disturbance on soil property changes was dependent on environmental conditions. Overall, my study shows evidence that grassland type and season have a stronger effect than prairie dog disturbance on the vegetation of this short-grass, water-restricted grassland ecosystem.:3 TABLE OF CONTENTS Declaration of conformity 2 1 Acknowledgments 3 2 Extended Summary 5 4 List of Figures 11 5 List of Tables 13 1 Introduction 1 1.1 Importance of grasslands 1 1.2 Grassland conservation and ecosystem engineers 2 1.3 Prairie dogs: ecosystem engineers of grasslands in North America 3 1.4 Distribution of prairie dogs across North American grasslands 6 1.5 Current threats and conservation of the Mexican prairie dog C. mexicanus 7 1.6 Research questions, aims and objectives 9 2 Scientific background 13 2.1 Differences in grassland definitions and classifications 13 2.2 Dryland biases in grassland research 13 2.3 Research gaps on C. mexicanus 15 2.4 Functional diversity and disturbance 16 2.5 Soil complexity and limited research 17 3 Study Area: Grassland Priority Conservation Area of El Tokio 19 3.1 General overview 19 3.2 Bioregions, geology, topography and soils 20 3.3 Climate 23 3.4 Ecoregions, Land cover and Biodiversity 24 3.5 Anthropogenic activities and environmental issues 28 4 Assessing and classifying factors that could influence prairie dog ecosystem engineering effects 31 4.1 Data-driven identification of grassland types 33 4.1.1 Introduction 33 4.1.2 Methods 33 4.1.3 Results 36 4.1.4 Discussion and conclusion 39 4.2 C. mexicanus colony trends and differences across grassland types 41 4.2.1 Introduction 41 4.2.2 Methods 42 4.2.3 Results 48 4.2.4 Discussion and conclusion 52 5 Prairie dog disturbance effects on vegetation and soil across different grassland types and seasons 55 5.1 General methodology 57 5.1.1 Selection of grassland locations 57 5.1.2 Defining study sites and plots 58 5.1.3 Vegetation and soil sampling design 59 5.2 The effect of C. mexicanus on taxonomical and functional diversity across different seasons and grassland types 61 5.2.1 Introduction 61 5.2.2 Methods 63 5.2.3 Results 65 5.2.4 Discussion and conclusion 72 5.3 Soil property responses to the presence of C. mexicanus and its mounds across different grassland types, seasons and depths 77 5.3.1 Introduction 77 5.3.2 Methods 78 5.3.3 Results 81 5.3.4 Discussion and conclusion 88 6 Synthesis 95 6.1 Key findings 95 6.2 Management and Conservation opportunities 97 6.2.1 Designing management plans to suit existing environmental conditions 97 6.2.2 Functional diversity: an opportunity to identify patterns of vegetation across environmental conditions and scales. 98 6.3 Future research 99 6.3.1 Exploration of spatial and temporal effects 99 6.3.2 Mechanistic understanding of disturbance dynamics 100 6.3.3 A need for plant and soil ecological data 101 7 References 103 8 Appendix 131 8.1 Appendix 1. Prairie dog research reference list 132 8.2 Appendix 2. List of individual colonies with areas and other relevant information 140 8.3 Appendix 3. Historical and present colony data. 142 8.4 Appendix 4. Correlation results 144 8.5 Appendix 5. Top 3 models 146 8.6 Appendix 6. Species list per grassland type. 151 8.7 Appendix 7. Correspondence analysis (CA) for each grassland 154 8.8 Appendix 8. Post-hoc results 155 8.9 Appendix 9. Top 3 dominant species. 157 8.10 Appendix 10. HPD credible interval and ROPE. 159
414

Nouvelles comptabilités au service des écosystèmes. Une recherche engagée auprès d'une entreprise du secteur de l'environnement. / New management accounting for ecosystems. An action research with an environmental sector company.

Feger, Clément 17 February 2016 (has links)
La lutte contre la destruction des écosystèmes et les efforts pour renforcer et renouveler les conditions de leur prise en charge collective reposent aujourd’hui sur trois fronts d’innovation disjoints : (1) la conception et l’utilisation de nouveaux outils d’évaluation des écosystèmes dans le champ de la conservation ; (2) le développement de nouvelles comptabilités socio-environnementales à l’échelle des organisations et (3) la mise à contribution des entreprises dans la protection du capital naturel. Cette thèse doctorale vise à les articuler en mobilisant la comptabilité comme pivot pour connecter les systèmes d’information écologique, les formes diverses d’organisation de l’action collective, et les initiatives et comptabilités des entreprises. Elle combine un travail de construction théorique et une recherche-intervention auprès d’une grande entreprise du secteur de l’environnement qui cherche à développer des activités de service dédiées à la qualité écologique des territoires. Nous proposons premièrement l’ouverture d’une nouvelle perspective d’innovation théorique et pratique, au croisement entre comptabilités et sciences de la conservation, et centrée sur la gestion collective de problèmes écologiques : le développement de « Comptabilités de Gestion pour les Ecosystèmes ». Nous montrons en quoi elles sont complémentaires de l’ensemble des autres types d’innovations comptables portant sur les écosystèmes. Nous proposons deuxièmement quatre grandes orientations organisationnelles et stratégiques pour penser et guider le développement de nouveaux modèles d’affaires de « services aux écosystèmes ». Afin de les compléter, nous ouvrons des pistes de conception de comptes et d’activités comptables pour accompagner une entreprise du secteur de l’environnement dans la négociation et la création collective de valeur écologique sur les territoires et dans la transformation de sa propre représentation et quantification de la valeur. / Current efforts to halt the destruction of the planet’s ecosystems and to reinforce and renew their collective management reside on three distinct innovation fronts: (1) the design and use of new ecosystem assessment tools by conservation scientists and practitioners; (2) the development of new social and environmental accounting frameworks and tools at the level of organization; (3) the contribution of the private sector to natural capital protection and maintenance. This doctoral thesis aims to relate these three domains of innovation to one another by mobilizing the accounting discipline as a pivot to connect ecological information systems and tools, diverse forms of collective action for ecosystem management, and private sector initiatives and accounting innovations. The thesis combines a work of theoretical construction with the results of an action-research conducted in an environmental sector company that seeks to develop new services specifically designed for the management of ecological systems. We first propose a new theoretical and practical perspective at the junction of accounting and conservation science centered on the collective management of ecological issues: the development of Management Accounting for Ecosystems. We show why and how they are complementary to all the other domains of ecosystem accounting innovation. Secondly, we introduce four organizational and strategic directions to think and guide the development of new “services to ecosystems” business models. To complement them, we suggest new accounts and accounting practices to help environmental sector companies negotiate and co-create ecological value with other stakeholders, and transform their own representation and quantification of corporate value.
415

Urban ecology in Christchurch: a reconciliation approach to enhancing native biodiversity on urban greyfields

Greenep, H. K. January 2009 (has links)
Traditionally New Zealand ecological research has focused on nature outside of cities, however, as with global trends, there is now more interest being given to the ecological functioning of cities and the potential they may hold for protecting native biodiversity. Traditionally, efforts to maintain biodiversity in urban areas have been restricted to remnants of native vegetation and restoration activities. Little attention has been given to how native biodiversity could be woven into the urban fabric in an ecologically meaningful way. One option, that is receiving much attention overseas, is to recruit underutilised urban spaces such as wasteland. A subset of urban wasteland, abandoned industrial areas usually awaiting development and other areas such as the railway buffer, are referred to here as greyfield. These are ephemeral sites that may sit between uses for as little as a few months to many years. Overseas, particularly in European countries, these have been recognised as important habitat for both native and introduced plant species. In New Zealand cities these support primarily introduced plants and their contribution to native biodiversity has been unknown. This thesis took an interdisciplinary approach to the question of whether urban greyfields might have potential value as biodiversity protection and conservation opportunity. Ecological methods were combined with an assessment of the planning framework to answer this question. iii Greyfields in Christchurch, New Zealand were surveyed to determine their current contribution to native biodiversity and whether they may act as urban analogues of natural habitats. Overseas research has shown that urban features such as pavements, walls and rooftops offer habitats analogous to cliffs and rocky habitats. Cities are therefore increasing the habitat exploitable by species whose natural habitats are geographically restricted. The Christchurch greyfields were assessed for their potential to act as analogues of four habitat types that have been categorised as historically rare in New Zealand: braided riverbeds, shingle beaches, rock outcrops and limestone outcrops. The findings suggest that urban greyfields, if managed appropriately, have the potential to support a wider range of native species Planning documents and biodiversity strategies written for Christchurch were assessed to see how well they facilitated non-traditional biodiversity enhancement initiatives, specifically the greyfield network for native biodiversity. A major finding here was a lack of information on how to enhance biodiversity where little of the natural features of the landscape were left and that this was creating a barrier to adopting more integrative approaches to enhancing native biodiversity. Finally, a plan to create a greyfield network for native biodiversity is proposed and suggestions are made as to minor changes to the planning framework that would more easily facilitate the uptake of novel biodiversity enhancement initiatives in the City.
416

Fragilidade ambiental potencial da bacia hidrogr?fica do rio Jequitinhonha, Minas Gerais, Brasil

Fran?a, Luciano Cavalcante de Jesus 26 January 2018 (has links)
Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2018-08-17T22:50:17Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) luciano_cavalcante_jesus_franca.pdf: 8536092 bytes, checksum: 448d28dd9ed3febc9eafc32bf9208be2 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2018-10-05T19:39:21Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) luciano_cavalcante_jesus_franca.pdf: 8536092 bytes, checksum: 448d28dd9ed3febc9eafc32bf9208be2 (MD5) / Made available in DSpace on 2018-10-05T19:39:21Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) luciano_cavalcante_jesus_franca.pdf: 8536092 bytes, checksum: 448d28dd9ed3febc9eafc32bf9208be2 (MD5) Previous issue date: 2018 / Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM) / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A degrada??o ambiental em seu contexto geral ? uma realidade presente em todo o Brasil, que vem desencadeando problemas de ordem ambiental, econ?mica e social, muitas vezes permanentes, outras contorn?veis dado o avan?o da pesquisa em restaura??o e conserva??o de ecossistemas degradados. Estudos de fragilidade ambiental potencial direcionam a compreens?o da susceptibilidade ? degrada??o em bacias hidrogr?ficas, e podem auxiliar na prioriza??o de ?reas no planejamento ambiental, ordenamento territorial, restaura??o, conserva??o e preserva??o florestal e de solos. O objetivo desta investiga??o cient?fica foi de realizar uma an?lise da fragilidade ambiental potencial da bacia hidrogr?fica do rio Jequitinhonha, na por??o do estado de Minas Gerais. A metodologia utilizada foi baseada no estabelecimento de graus de fragilidade, de baixo ? extremamente alto, a partir de avalia??o muticriterial de um conjunto de planos de informa??es ambientais: declividade do terreno, classes de solos, dom?nios geol?gicos, hierarquia de drenagens e pluviosidade. Aplicou-se o m?todo de hierarquiza??o para tomada de decis?es e determina??o da import?ncia dos crit?rios por meio do Analytic Hierarchy Process (AHP), bem como a obten??o do ?ndice e raz?o de consist?ncia da matriz AHP. Para os procedimentos de an?lises em planilhas de dados, utilizou-se o software Excel, e para as an?lises em plataforma SIG, o software ArcGis 10.3.1. A classe de fragilidade ambiental potencial com maior representatividade ? a denominada m?dia fragilidade, e ocorre em uma extens?o de 19.244,1 km?, equivalente a 30% da ?rea total da bacia hidrogr?fica, que ? de 66.319 km?. Uma ?rea de 12.430,57 km? (19,4%) da bacia apresenta fragilidade baixa, 18.540,93 km? (28,9%) sob levemente baixa, e as classe alta e extremamente alta, representam 10.519,63 km? (16,4%) e 3.416,15 km? (5,3%), respectivamente. A Raz?o de Consist?ncia (RC) calculada para a matriz de pondera??o de hierarquiza??o dos crit?rios para a ?lgebra de mapas, foi de 0,0781, dentro dos limites de coer?ncia e confiabilidade aceit?veis pela metodologia AHP. A condi??o de maior ou menor fragilidade ambiental potencial, revela-se principalmente ao grau de prote??o quanto a cobertura vegetal nativa, no contexto das formas de ocupa??o do territ?rio e impactos ambientais sob o qual a bacia hidrogr?fica est? sujeita, condi??es que direcionam ou n?o ? degrada??o dos solos. Destaca-se que, al?m dos resultados obtidos neste estudo, s?o necess?rias outras investiga??es que complementem e testem a combina??o de novos crit?rios, que englobem tamb?m distintos focos de aplicabilidade e tomadas de decis?o nas ci?ncias florestal, ambiental e agr?ria. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Ci?ncia Florestal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2018. / The environmental degradation in its general context is a reality present throughout Brazil, which has been unleashing environmental, economic and social problems, which are often permanent, others that are contrived due to the progress of research in restoration and conservation of degraded ecosystems. Potential environmental fragility studies guide the understanding of susceptibility to degradation in watersheds, and may assist in the prioritization of areas in environmental planning, land management, restoration, forest and soil conservation and preservation. The objective of this scientific investigation was to analyze the potential environmental fragility of the Jequitinhonha river basin in the state of Minas Gerais. The methodology used was based on the establishment of degrees of fragility, from low to extremely high, based on a multi-criteria assessment of a set of environmental information plans: terrain slope, soil classes, geological domains, drainage hierarchy and rainfall. The hierarchical method was applied for decision making and determination of the importance of the criteria through the Analytic Hierarchy Process (AHP), as well as obtaining the index and consistency ratio of the AHP matrix. For the analysis procedures in spreadsheets, the software Excel was used, and for the analyzes in platform GIS, the software ArcGis 10.3.1. The class of potential environmental fragility with greater representativeness is the denominated average fragility, and occurs in an extension of 19.244,1 km ?, equivalent to 30% of the total area of the watershed, that is of 66.319 km ?. An area of 12,430.57 km? (19.4%) of the basin presents low fragility, 18,540.93 km? (28.9%) under slightly low, and the upper and extremely high class represent 10,519.63 km? (16.4 %) and 3,416.15 km? (5.3%), respectively. The Consistency Ratio (RC) calculated for the hierarchy matrix of the criteria for map algebra was 0.0781, within the limits of coherence and reliability acceptable by the AHP methodology. The condition of greater or lesser potential environmental fragility is mainly due to the degree of protection of native vegetation cover, in the context of the forms of occupation of the territory and environmental impacts under which the river basin is subject, conditions that degradation of soils. In addition to the results obtained in this study, further research is required to complement and test the combination of new criteria, which also encompasses different foci of applicability and decision making in the forest, environmental and agrarian sciences.
417

Fragilidade ambiental potencial da bacia hidrogr?fica do Rio Jequitinhonha, Minas Gerais, Brasil / Potential environmental fragility of the hydrographic basin of Jequitinhonha River, Minas Gerais, Brazil

Fran?a, Luciano Cavalcante de Jesus 26 January 2018 (has links)
Submitted by Luciano Fran?a (lucianodejesus@florestal.eng.br) on 2018-03-06T00:03:11Z No. of bitstreams: 3 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Declaracao Orientadora.pdf: 1388830 bytes, checksum: e157d539359c6d1e74bcc641d6e7d190 (MD5) Disserta??o Luciano Cavalcante de Jesus Fran?a.pdf: 8643521 bytes, checksum: ad5a66f3b0d0e6337cfe0945a3405b26 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2018-03-06T12:06:00Z (GMT) No. of bitstreams: 3 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Declaracao Orientadora.pdf: 1388830 bytes, checksum: e157d539359c6d1e74bcc641d6e7d190 (MD5) Disserta??o Luciano Cavalcante de Jesus Fran?a.pdf: 8643521 bytes, checksum: ad5a66f3b0d0e6337cfe0945a3405b26 (MD5) / Made available in DSpace on 2018-03-06T12:06:00Z (GMT). No. of bitstreams: 3 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Declaracao Orientadora.pdf: 1388830 bytes, checksum: e157d539359c6d1e74bcc641d6e7d190 (MD5) Disserta??o Luciano Cavalcante de Jesus Fran?a.pdf: 8643521 bytes, checksum: ad5a66f3b0d0e6337cfe0945a3405b26 (MD5) Previous issue date: 2018 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A degrada??o ambiental em seu contexto geral ? uma realidade presente em todo o Brasil, que vem desencadeando problemas de ordem ambiental, econ?mica e social, muitas vezes permanentes, outras contorn?veis dado o avan?o da pesquisa em restaura??o e conserva??o de ecossistemas degradados. Estudos de fragilidade ambiental potencial direcionam a compreens?o da susceptibilidade ? degrada??o em bacias hidrogr?ficas, e podem auxiliar na prioriza??o de ?reas no planejamento ambiental, ordenamento territorial, restaura??o, conserva??o e preserva??o florestal e de solos. O objetivo desta investiga??o cient?fica foi de realizar uma an?lise da fragilidade ambiental potencial da bacia hidrogr?fica do rio Jequitinhonha, na por??o do estado de Minas Gerais. A metodologia utilizada foi baseada no estabelecimento de graus de fragilidade, de baixo ? extremamente alto, a partir de avalia??o muticriterial de um conjunto de planos de informa??es ambientais: declividade do terreno, classes de solos, dom?nios geol?gicos, hierarquia de drenagens e pluviosidade. Aplicou-se o m?todo de hierarquiza??o para tomada de decis?es e determina??o da import?ncia dos crit?rios por meio do Analytic Hierarchy Process (AHP), bem como a obten??o do ?ndice e raz?o de consist?ncia da matriz AHP. Para os procedimentos de an?lises em planilhas de dados, utilizou-se o software Excel, e para as an?lises em plataforma SIG, o software ArcGis 10.3.1. A classe de fragilidade ambiental potencial com maior representatividade ? a denominada m?dia fragilidade, e ocorre em uma extens?o de 19.244,1 km?, equivalente a 30% da ?rea total da bacia hidrogr?fica, que ? de 66.319 km?. Uma ?rea de 12.430,57 km? (19,4%) da bacia apresenta fragilidade baixa, 18.540,93 km? (28,9%) sob levemente baixa, e as classe alta e extremamente alta, representam 10.519,63 km? (16,4%) e 3.416,15 km? (5,3%), respectivamente. A Raz?o de Consist?ncia (RC) calculada para a matriz de pondera??o de hierarquiza??o dos crit?rios para a ?lgebra de mapas, foi de 0,0781, dentro dos limites de coer?ncia e confiabilidade aceit?veis pela metodologia AHP. A condi??o de maior ou menor fragilidade ambiental potencial, revela-se principalmente ao grau de prote??o quanto a cobertura vegetal nativa, no contexto das formas de ocupa??o do territ?rio e impactos ambientais sob o qual a bacia hidrogr?fica est? sujeita, condi??es que direcionam ou n?o ? degrada??o dos solos. Destaca-se que, al?m dos resultados obtidos neste estudo, s?o necess?rias outras investiga??es que complementem e testem a combina??o de novos crit?rios, que englobem tamb?m distintos focos de aplicabilidade e tomadas de decis?o nas ci?ncias florestal, ambiental e agr?ria. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Ci?ncia Florestal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2018. / The environmental degradation in its general context is a reality present throughout Brazil, which has been unleashing environmental, economic and social problems, which are often permanent, others that are contrived due to the progress of research in restoration and conservation of degraded ecosystems. Potential environmental fragility studies guide the understanding of susceptibility to degradation in watersheds, and may assist in the prioritization of areas in environmental planning, land management, restoration, forest and soil conservation and preservation. The objective of this scientific investigation was to analyze the potential environmental fragility of the Jequitinhonha river basin in the state of Minas Gerais. The methodology used was based on the establishment of degrees of fragility, from low to extremely high, based on a multi-criteria assessment of a set of environmental information plans: terrain slope, soil classes, geological domains, drainage hierarchy and rainfall. The hierarchical method was applied for decision making and determination of the importance of the criteria through the Analytic Hierarchy Process (AHP), as well as obtaining the index and consistency ratio of the AHP matrix. For the analysis procedures in spreadsheets, the software Excel was used, and for the analyzes in platform GIS, the software ArcGis 10.3.1. The class of potential environmental fragility with greater representativeness is the denominated average fragility, and occurs in an extension of 19.244,1 km ?, equivalent to 30% of the total area of the watershed, that is of 66.319 km ?. An area of 12,430.57 km? (19.4%) of the basin presents low fragility, 18,540.93 km? (28.9%) under slightly low, and the upper and extremely high class represent 10,519.63 km? (16.4 %) and 3,416.15 km? (5.3%), respectively. The Consistency Ratio (RC) calculated for the hierarchy matrix of the criteria for map algebra was 0.0781, within the limits of coherence and reliability acceptable by the AHP methodology. The condition of greater or lesser potential environmental fragility is mainly due to the degree of protection of native vegetation cover, in the context of the forms of occupation of the territory and environmental impacts under which the river basin is subject, conditions that degradation of soils. In addition to the results obtained in this study, further research is required to complement and test the combination of new criteria, which also encompasses different foci of applicability and decision making in the forest, environmental and agrarian sciences.
418

A Namibian digital health innovation ecosystem framework

Iyawa, Gloria Ejehiohen 02 1900 (has links)
Digital Health relates to “health information systems which enable the merging of social-care and healthcare systems. This would impact on the organisation, service delivery as well as the technological infrastructure” (Herselman & Botha, 2016, p.10). However, with relatively sparse research publications emanating from within the Namibian Health domain, and the concept of Namibian Digital Health as an emergent phenomenon, a Namibian Digital Health Innovation Ecosystem Framework would provide a start to conceptualising, developing and implementing such an ecosystem for Namibia and thus unlocking the potential of Digital Health in this country. The purpose of this study is to develop a Namibian Digital Health Innovation Ecosystem Framework based on literature reviews and the feedback from knowledgeable professionals (KPs) in Namibia, as well as global experts. The methodology which was applied in this study to address the purpose, and to answer the research questions, was Design Science Research Methodology and the Design Science Research Methodology (DSRM) process of Peffers, Tuunanen, Rothenberger and Chatterjee (2008), was adopted. Pragmatism is the overall philosophy guiding the study, as proposed by Ackoff’s theory regarding the hierarchy of human understanding (1989) and Shneiderman’s visual information seeking mantra (1996). During Phases 2 and 3 of the study interpretivism and positivism were applied as philosophies, guided by hermeneutics and triangulation, towards understanding the feedback of Knowledgeable Professionals (KPs) in Namibia, as well as the global experts. The study was divided into three phases. The first phase entailed a literature study which identified the components of Digital Health, Innovation and Digital Ecosystems as well as related research of Digital health, Innovation and Digital Ecosystems in developed and developing countries. This process led to the compilation of the initial Namibian Digital Health Innovation Ecosystem Framework using a conceptual approach. In the second phase of the study, the initial Namibian Digital Health Innovation Ecosystem was evaluated by KPs in Namibia using the Delphi method and interviews. Phase 2 adopted both quantitative and qualitative approaches. The findings from Phase 2 resulted in the development of the intermediate Namibian Digital Health Innovation Ecosystem Framework. In Phase 3 of the study, the intermediate framework was validated by global experts. Feedback was collected from global experts through questionnaires which were analysed through qualitative content analysis. The findings, from Phase 3 led to the development of the final Namibian Digital Health Innovation Ecosystems Framework. The guidelines, which can be used by the Namibian government to implement the suggested digital health innovation ecosystem framework, were also provided. / Information Science / D. Litt. et Phil. (Information Systems)
419

L’influence des subsides particulaires terrestres et leur stoechiométrie sur les communautés benthiques littorales d’invertébrés en lacs

Charette, Georges-Étienne 03 1900 (has links)
Il est de plus en plus clair que nos écosystèmes sont liés les uns aux autres de façons multiples et parfois complexes. De plus en plus nous identifions de nouvelles façons dont deux systèmes échangent des ressources et de l’énergie. Le rôle de ces échanges et transferts est encore difficile à quantifier. Nous en savons relativement peu sur les interactions de ceux-ci avec des processus locaux et spatiaux, ainsi que sur leur importance relativement à ces processus locaux et régionaux plus connus. À travers ce projet, nous cherchons à éclaircir l’importance relative des subsides particulaires de feuilles (et particulièrement de leur stoechiométrie) sur les communautés littorales d’invertébrés benthiques. Nous avons récolté des invertébrés et des feuilles mortes sur 23 sites à travers 7 lacs relativement isolés de l’influence humaine et avons comparé l’influence de la stoechiométrie de ces subsides à l’influence de facteurs locaux de qualité de l’eau et de facteurs spatiaux. Les résultats suggèrent que l’importance de la qualité nutritive (i.e. stoechiométrie) est secondaire aux facteurs locaux de qualité de l’eau dans des milieux naturels. L’importance des subsides particulaires de feuilles semble être grandement dépendante du contexte et pourrait gagner en importance dans des contextes de fortes perturbations. Les résultats indiquent que la qualité nutritive des subsides de feuilles, leur contenu relatif en azote et phosphore, est associée avec de plus grande abondance de plusieurs taxons. La richesse spécifique n’étant pas affecté, c’est à travers l’équitabilité (i.e. une distribution des abondances plus stable) que la qualité nutritive des feuilles pourrait promouvoir une plus grande biodiversité d’invertébrés benthiques. / It is clear now, more than ever before, that our ecosystems are linked to one another in multiples and sometimes complex ways. The role of these exchanges and transfers is still hard to quantify. We know little of the interactions of these fluxes with local and spatial processes happening in ecosystems, as well as their relative importance compared to local and regional drivers of ecosystem functions and community structure. With this project, we aim to untangle the relative importance of particulate subsidies of leaves (and specifically their stoichiometry) on littoral communities of benthic invertebrates in lakes. We collected invertebrates and leaf litter on 23 sites across 7 lakes somewhat isolated from human influence and compared the influence of leaf litter stoichiometry to the influence of local water quality and spatial variables. Results suggest that nutritive quality of leaf litter (i.e. stoichiometry) is secondary to water quality. Importance of leaf subsidies appears to be context dependant and could gain in importance in systems with higher degrees of disturbances. Results that nitrogen and phosphorus content of leaf subsidies is associated with higher abundances of several taxonomic groups. Species richness being unaffected, it is through higher evenness (i.e. even distribution of abundances) that higher quality of leaves may promote higher biodiversity of benthic invertebrates.
420

Research on the status of chemical pesticide uses in agricultural activities in Phan Me commune, Phu Luong district, Thai Nguyen province / Nghiên cứu thực trạng sử dụng thuốc bảo vệ thực vật trong sản xuất nông nghiệp trên địa bàn xã Phấn Mễ, huyện Phú Lương, tỉnh Thái Nguyên

Nguyen, Thi Hue, Ha, Dinh Nghiem 09 December 2015 (has links) (PDF)
Phan Me is a midland-mountainous commune of Phu Luong district, Thai Nguyen province, Vietnam where the agricultural activities are predominant occupation. The investigation on the use of plant protection products in here showed that chemical pesticides have been commonly used in agricultural activities. Although some local people have a good attitude in using plant protection products, the status of using chemical pesticides that were not recommended (like Vofatox) has been quite popular due to the old cultivation customs. The local people have not applied any measures for wastewater treatment, or plant protection product package treatment. Besides, the use of plant protection products in higher concentration than recommendation for vegetables or crops caused the residues of toxics in agricultural products as well as in cultivation soil. The accumulation of toxic residues in the environment is a serious matter of concern because of their significant impact on the environment, agricultural ecosystem and human health. / Phấn Mễ là một xã trung du miền núi của huyện Phú Lương, tỉnh Thái Nguyên, Việt Nam với hoạt động sản xuất nông nghiệp là chủ yếu. Qua thực tế điều tra tình hình sử dụng thuốc bảo vệ thực vật (BVTV) tại đây cho thấy hầu hết các loại hình sản xuất nông nghiệp đều sử dụng thuốc BVTV. Một số người dân đã có ý thức trong việc sử dụng thuốc BVTV tuy nhiên do tập quán canh tác từ lâu đời nên việc sử dụng các loại thuốc bị khuyến cáo, chẳng hạn như Vofatox, vẫn còn khá phổ biến. Người dân chưa tiến hành các biện pháp để xử lý nước thải, bao bì, vỏ chai thuốc BVTV sau khi sử dụng. Bên canh đó, họ còn sử dụng thuốc BVTV không đúng liều lượng cho một số loại cây rau để lại dư lượng thuốc trên nông sản cũng như đất canh tác. Sự tích lũy dư lượng của những chất độc hại này trong môi trường là vấn đề đáng lo ngại do sự ảnh hưởng nghiêm trọng của chúng đối với môi trường sống, hệ sinh thái nông nghiệp và sức khỏe con người.

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