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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

O efeito da fragmentação na diversidade específica e funcional de primatas no Brasil / Effect of fragmentation in specific and functional diversity of primates in Brazil

Campos, Vanessa Ellen Wendt [UNESP] 30 March 2016 (has links)
Submitted by VANESSA ELLEN WENDT CAMPOS null (vanessaellen@hotmail.com) on 2016-07-14T18:11:05Z No. of bitstreams: 1 Vanessa_Completo.pdf: 3530663 bytes, checksum: fa3beebf319fc93620723a321d5c7529 (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-07-18T20:26:08Z (GMT) No. of bitstreams: 1 campos_vew_me_rcla.pdf: 3530663 bytes, checksum: fa3beebf319fc93620723a321d5c7529 (MD5) / Made available in DSpace on 2016-07-18T20:26:08Z (GMT). No. of bitstreams: 1 campos_vew_me_rcla.pdf: 3530663 bytes, checksum: fa3beebf319fc93620723a321d5c7529 (MD5) Previous issue date: 2016-03-30 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / As florestas tropicais representam um dos biomas mais ameaçados pelas ações antrópicas no mundo. Os primatas representam 40% da biomassa de vertebrados frugívoros nas florestas tropicais, mas mais da metade das espécies estão ameaçadas de extinção. Tendo em vista a importância dos primatas no funcionamento dos ecossistemas devido a sua função de dispersores de sementes, é de extrema relevância entender como a fragmentação das florestas tropicais afetam as comunidades de primatas e suas funções. Portanto, nossos objetivos são: 1) analisar a relação entre diversidade funcional e filogenética de primatas e como esses índices são influenciados pela riqueza; 2) determinar o efeito da fragmentação das florestas tropicais na riqueza específica e funcional dos primatas; 3) determinar quais características funcionais são perdidas com a fragmentação, na Amazônia e na Mata Atlântica brasileira. Para isso, montamos bancos de dados de ocorrência dos primatas e de suas características funcionais ligadas à dispersão de sementes para gerar os índices de diversidade funcional (FD), regularidade funcional (FEve) e divergência funcional (FDiv) e relacioná-los com métricas da paisagem: área do fragmento, isolamento médio entre os fragmentos, distância em relação à zona urbana, distância à floresta contínua, conectividade funcional e porcentagem de cobertura vegetal no entorno do fragmento. A diversidade funcional dos primatas é fortemente correlacionada com a diversidade filogenética (R2= 0.94 e p<0.001). A redução da área dos fragmentos e da conectividade funcional, assim como o aumento do isolamento médio entre os remanescentes florestais diminuem a diversidade (FD), a regularidade (FEve) e a divergência funcional (FDiv) dos primatas. As espécies de primatas de grande porte que possuem grandes áreas de vida e que dispersam grandes sementes são as espécies mais prejudicadas pela fragmentação. Nosso trabalho permitiu ressaltar que além da perda de riqueza específica de primatas, a fragmentação nas florestas tropicais também afeta o serviço de dispersão de sementes, o que, consequentemente, pode alterar a estrutura das comunidades vegetais. / Tropical forests are the most threatened biome by human activities worldwide. Primates represent almost 40% of the frugivore vertebrate biomass in tropical forests and more than half of their species are threatened by extinction. Given the importance of primates as seed dispersers for the ecosystem functioning, it is extremely important to understand how the fragmentation of tropical forests affects primate communities and the functions they provide. Therefore, this project aims at: 1) analyzing the relationship between primate functional and phylogenetic diversities and how those indices are influenced by species richness; 2) determining the influence of forest fragmentation on primate species richness and functional diversity; 3) determining which functional traits are lost with habitat fragmentation, in Amazonian and Atlantic Forests of Brazil. To do this, we built a database of primates’ occurrence and their functional traits related to seed dispersal to compute indices of functional diversity (FD), functional evenness (Feve) and functional divergence (FDiv). Then, we related these indices to landscape metrics: patch size, average isolation between patches, distance to the nearest urban area, distance to the nearest continuous forest, functional connectivity and percentage of forest cover surrounding the fragment. Functional diversity is strongly correlated with phylogenetic diversity (R2= 0.94 e p<0.001). The decrease of fragment areas and functional connectivity, and the increase of average isolation between forest remnants, reduce primate functional diversity (FD), regularity (FEve) and divergence (FDiv). Large primates with large home ranges that disperse large seeds are the most affected by fragmentation. Our results enable highlighting that beyond the loss of primate species richness, the fragmentation of tropical forests also affect seed dispersal service, which consequently may alter the structure of plant communities. / FAPESP: 2014/14739-0 / CNPq: 830816/1999-2
2

Monoterpene production and regulation in lavenders (Lavandula angustifolia and Lavandula x intermedia)

Boeckelmann, Astrid 11 1900 (has links)
Lavenders (Lavandula) are widely grown for their essential oils, which have extensive applications in cosmetics, hygiene products and alternative medicine. The therapeutic and olfactory properties of lavender essential oils are attributed to monoterpenes, a class of low molecular weight (C₁₀) isoprenoids. Oil composition in these plants is primarily determined by plant genotype, but can also be influenced by developmental and environmental factors. In order to define some of the mechanisms that control monoterpene abundance in lavenders, I measured the abundance of quality-defining monoterpenes in several L. angustifolia and L. x intermedia cultivars grown in the Okanagan. Data obtained confirmed that essential oil yield, as well as the abundance of camphor, borneol, linalool, and limonene was species-specific. L. angustifolia cultivars contained high amounts of linalool but yielded little oil, whereas L. x intermedia cultivars were rich in camphor and total oil. Monoterpene abundance changed during flower development, and differed between vegetative and reproductive tissues indicating differential regulation of the biosynthetic pathways, or specialized ecological functions. The abundance of linalool correlated with the transcription of the linalool synthase gene, suggesting that linalool production is in part regulated transcriptionally. However, the degree of correlation between linalool abundance and linalool synthase transcription differed between L. angustifolia and L. x intermedia, suggesting additional, and differing mechanisms that control linalool abundance in these species. In addition, monoterpene abundances were subject to loss during storage and suboptimal detection, two factors that must be considered in future analyses. Results obtained in this study provide insight into the regulation of monoterpene production in lavenders, and build the basis for future research aimed at improving essential oil production in these plants.
3

Monoterpene production and regulation in lavenders (Lavandula angustifolia and Lavandula x intermedia)

Boeckelmann, Astrid 11 1900 (has links)
Lavenders (Lavandula) are widely grown for their essential oils, which have extensive applications in cosmetics, hygiene products and alternative medicine. The therapeutic and olfactory properties of lavender essential oils are attributed to monoterpenes, a class of low molecular weight (C₁₀) isoprenoids. Oil composition in these plants is primarily determined by plant genotype, but can also be influenced by developmental and environmental factors. In order to define some of the mechanisms that control monoterpene abundance in lavenders, I measured the abundance of quality-defining monoterpenes in several L. angustifolia and L. x intermedia cultivars grown in the Okanagan. Data obtained confirmed that essential oil yield, as well as the abundance of camphor, borneol, linalool, and limonene was species-specific. L. angustifolia cultivars contained high amounts of linalool but yielded little oil, whereas L. x intermedia cultivars were rich in camphor and total oil. Monoterpene abundance changed during flower development, and differed between vegetative and reproductive tissues indicating differential regulation of the biosynthetic pathways, or specialized ecological functions. The abundance of linalool correlated with the transcription of the linalool synthase gene, suggesting that linalool production is in part regulated transcriptionally. However, the degree of correlation between linalool abundance and linalool synthase transcription differed between L. angustifolia and L. x intermedia, suggesting additional, and differing mechanisms that control linalool abundance in these species. In addition, monoterpene abundances were subject to loss during storage and suboptimal detection, two factors that must be considered in future analyses. Results obtained in this study provide insight into the regulation of monoterpene production in lavenders, and build the basis for future research aimed at improving essential oil production in these plants.
4

Macroalgae in tropical seascapes : regulating factors and functions in the coastal ecosystem

Lilliesköld Sjöö, Gustaf January 2010 (has links)
Although macroalgae usually are inconspicuous on pristine coral reefs, they often thrive on reefs that are subjected to various types of anthropogenic disturbance. This thesis consists of five papers and investigates how biomass and composition of macroalgal communities on coral reefs are affected by regulating factors, such as nutrient availability, herbivory, substrate availability and hydrodynamic forces. In addition, ecological functions and potential impacts of both wild and farmed macroalgal communities are evaluated. Paper I describes a method for using macroalgal tissue nutrient concentrations as bioindicator for nutrient availability, with the possibility to map nutrient loading from larger coastal cities. Papers II and III are manipulative studies comparing top-down and bottom-up regulation of macroalgal communities, where herbivore consumption seems to be the main regulator of biomass whereas nutrient availability mainly influences community composition. Exclosure of large-bodied herbivores had a positive influence on algal biomass in both studies, and during different climatic periods. Paper III also includes the influence of hydrodynamic forces on algal community biomass and structure by comparing a reef crest and a back reef-habitat. Alterations of top-down and bottom-up regulation generally had a stronger effect within the protected back reef-habitat, suggesting that such environments may be more sensitive to anthropogenic influence. Paper IV confirms the general conclusions from papers II and III by studying macroalgal biomass and composition on reef sites with different environmental prerequisites. This study also supports the notion that herbivorous fish can suppress accumulation of macroalgal biomass if substrate availability is low, but not where coral cover is reduced and plenty of substrate is open to macroalgal colonization. The study also found a large temporal variation of macroalgal standing stock and associated nutrients at sites with low top-down regulation. Paper V evaluates potential impacts of seaweed farming on coral reefs and nutrients in the seascape by experimentally studying growth, survival and nutrient binding capacity of Eucheuma denticulatum. This study showed that seaweed farms counteract eutrophication through nutrient extraction and that the risk of farmed algae colonizing local reefs seems to be small as they were rapidly consumed. In conclusion, the studies in this thesis contribute to the understanding of macroalgal regulation and function in tropical seascapes, thereby adding to the knowledge base for coastal management. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript. Paper 5: Manuscript.</p>
5

Monoterpene production and regulation in lavenders (Lavandula angustifolia and Lavandula x intermedia)

Boeckelmann, Astrid 11 1900 (has links)
Lavenders (Lavandula) are widely grown for their essential oils, which have extensive applications in cosmetics, hygiene products and alternative medicine. The therapeutic and olfactory properties of lavender essential oils are attributed to monoterpenes, a class of low molecular weight (C₁₀) isoprenoids. Oil composition in these plants is primarily determined by plant genotype, but can also be influenced by developmental and environmental factors. In order to define some of the mechanisms that control monoterpene abundance in lavenders, I measured the abundance of quality-defining monoterpenes in several L. angustifolia and L. x intermedia cultivars grown in the Okanagan. Data obtained confirmed that essential oil yield, as well as the abundance of camphor, borneol, linalool, and limonene was species-specific. L. angustifolia cultivars contained high amounts of linalool but yielded little oil, whereas L. x intermedia cultivars were rich in camphor and total oil. Monoterpene abundance changed during flower development, and differed between vegetative and reproductive tissues indicating differential regulation of the biosynthetic pathways, or specialized ecological functions. The abundance of linalool correlated with the transcription of the linalool synthase gene, suggesting that linalool production is in part regulated transcriptionally. However, the degree of correlation between linalool abundance and linalool synthase transcription differed between L. angustifolia and L. x intermedia, suggesting additional, and differing mechanisms that control linalool abundance in these species. In addition, monoterpene abundances were subject to loss during storage and suboptimal detection, two factors that must be considered in future analyses. Results obtained in this study provide insight into the regulation of monoterpene production in lavenders, and build the basis for future research aimed at improving essential oil production in these plants. / Graduate Studies, College of (Okanagan) / Graduate
6

Urbanization Increases Seed Dispersal Interaction Diversity but Decreases Dispersal Success in Toxicodendron Radicans

Stanley, Amber, Arceo-Gómez, Gerardo 01 June 2020 (has links)
Urbanization is increasing at a rapid pace with negative consequences for native biodiversity. While it is well-known that urbanization can lead to biotic homogenization (dominance of a few competitive species), effects of urbanization on ecological functions that rely on the frequency and efficiency of species interactions are less understood. Seed dispersal success depends on seed disperser feeding rate and diversity, which can affect the probability of fruit removal (i.e. seed dispersal) and germination rates. However, how these factors are affected by urbanization is unknown. In this study, we evaluate the effects of urbanization on factors that contribute to seed dispersal success (seed disperser diversity, frequency, probability of fruit removal and germination rate using Toxicodendron radicans and its seed disperser community as a model system. We found that urban sites had three times more disperser species and two times higher feeding rate compared to natural sites. However, the probability of individual fruit removal did not differ between natural and urban sites. Moreover, germination rate after dispersal was 20% lower in urban sites, leading to overall negative effects of urbanization on T. radicans seed dispersal. We propose differences in seed germination rate are driven by changes in seed disperser species composition and their differences in seed gut transit time. This in turn affects disperser species’ ability to successfully scarify seeds. Overall, our results highlight the need to evaluate urbanization's effects on functional ecological processes, in addition to biotic homogenization effects, in order better understand and mitigate its negative impacts on biodiversity.
7

Diversidade e riqueza funcional de assembleias de aves na Mata Atlântica / Functional richness and diversity of bird assemblages in the Atlantic Forest

Bovo, Alex Augusto de Abreu 02 February 2016 (has links)
A composição das assembleias de aves sofre mudanças de acordo com alterações na paisagem em que ocorrem. A transição de florestas para outros usos do solo pode modificar também o conjunto de funções e, consequentemente, impactar os processos ecológicos desempenhados pelas aves. Desse modo, a presente dissertação teve como objetivos principais: 1) identificar características da estrutura da paisagem que apresentem relação com a diversidade e riqueza funcional de assembleias de aves; e 2) identificar alterações morfológicas na assembleia de aves consumidoras de frutos e discutir seus possíveis impactos no processo de dispersão de sementes. Para isso, um levantamento bibliográfico foi realizado resultando em um banco de dados com 48 assembleias de fragmentos florestais da Mata Atlântica oriundas de 33 estudos. Para cada fragmento foi utilizado um buffer de 2000 m de raio para criar uma paisagem focal, o uso do solo foi classificado em \'floresta\' ou \'não-floresta\', e métricas foram calculadas. As assembleias de aves foram caracterizadas a partir de índices de composição de diversidade e riqueza funcional, usando diversas características morfológicas e de habitat. Regressões lineares e modelos mistos foram usadas para investigar a relação entre características da estrutura da paisagem e i) diversidade e riqueza funcional de aves florestais (obj. 1) e ii) riqueza de espécies, diversidade funcional e características morfológicas para aves consumidoras de frutos (obj. 2). Os resultados mostraram que a área do fragmento, juntamente com área nuclear foram as características mais importantes em relação à manutenção das funções na assembleia de aves florestais, demonstrando a importância de grandes áreas florestais. Para as alterações morfológicas, a diminuição na quantidade de cobertura florestal foi relacionada à diminuição de valores de massa corpórea, índice de asa e largura de bico. A redução desses valores pode implicar na dispersão de sementes menores, na redução de dispersão de espécies com sementes grandes e na redução da área abrangida pela chuva de sementes. / Bird assemblages composition suffer alteration according to landscape changes. The substitution of forest by others land uses can affect the group of functions, and consequently, the ecological process played by birds. This dissertation had two main goals: 1) to identify landscape metrics which has relation with functional diversity and richness of bird assemblages; and 2) to identify morphological changes in fruit-eater bird assemblage and discuss the potentials impacts on the seed dispersal process. To reach this, a database was created using literature data, with 48 bird assemblages of Atlantic Forest remnants from 33 studies. From the most central point of each fragment, was created a focal landscape of 2000 meters buffer, the land use was classified in \'forest\' or \'non-forest\' and metrics was calculated. The index of bird assemblages used were composition and functional diversity and richness, calculated using morphological and habitat traits. Linear regression and mixed models were used to investigate relationships between landscape metrics and i) functional diversity and richness of forest birds (obj. 1) and ii) functional diversity, species richness and morphological traits of fruit-eater birds (obj. 2). The results showed that fragment area and core area were the most important traits to preserve the functions in bird assemblage, demonstrating the importance of big blocks of forest. To morphological changes, the decreasing on forest over was related to decreases on values of: body mass, hand-wing index and bill width. The reduction of these values can promote the dispersal of smaller seeds, reduction on dispersal of plants with big seed and decreases of area cover by seed rain.
8

Diversidade e riqueza funcional de assembleias de aves na Mata Atlântica / Functional richness and diversity of bird assemblages in the Atlantic Forest

Alex Augusto de Abreu Bovo 02 February 2016 (has links)
A composição das assembleias de aves sofre mudanças de acordo com alterações na paisagem em que ocorrem. A transição de florestas para outros usos do solo pode modificar também o conjunto de funções e, consequentemente, impactar os processos ecológicos desempenhados pelas aves. Desse modo, a presente dissertação teve como objetivos principais: 1) identificar características da estrutura da paisagem que apresentem relação com a diversidade e riqueza funcional de assembleias de aves; e 2) identificar alterações morfológicas na assembleia de aves consumidoras de frutos e discutir seus possíveis impactos no processo de dispersão de sementes. Para isso, um levantamento bibliográfico foi realizado resultando em um banco de dados com 48 assembleias de fragmentos florestais da Mata Atlântica oriundas de 33 estudos. Para cada fragmento foi utilizado um buffer de 2000 m de raio para criar uma paisagem focal, o uso do solo foi classificado em \'floresta\' ou \'não-floresta\', e métricas foram calculadas. As assembleias de aves foram caracterizadas a partir de índices de composição de diversidade e riqueza funcional, usando diversas características morfológicas e de habitat. Regressões lineares e modelos mistos foram usadas para investigar a relação entre características da estrutura da paisagem e i) diversidade e riqueza funcional de aves florestais (obj. 1) e ii) riqueza de espécies, diversidade funcional e características morfológicas para aves consumidoras de frutos (obj. 2). Os resultados mostraram que a área do fragmento, juntamente com área nuclear foram as características mais importantes em relação à manutenção das funções na assembleia de aves florestais, demonstrando a importância de grandes áreas florestais. Para as alterações morfológicas, a diminuição na quantidade de cobertura florestal foi relacionada à diminuição de valores de massa corpórea, índice de asa e largura de bico. A redução desses valores pode implicar na dispersão de sementes menores, na redução de dispersão de espécies com sementes grandes e na redução da área abrangida pela chuva de sementes. / Bird assemblages composition suffer alteration according to landscape changes. The substitution of forest by others land uses can affect the group of functions, and consequently, the ecological process played by birds. This dissertation had two main goals: 1) to identify landscape metrics which has relation with functional diversity and richness of bird assemblages; and 2) to identify morphological changes in fruit-eater bird assemblage and discuss the potentials impacts on the seed dispersal process. To reach this, a database was created using literature data, with 48 bird assemblages of Atlantic Forest remnants from 33 studies. From the most central point of each fragment, was created a focal landscape of 2000 meters buffer, the land use was classified in \'forest\' or \'non-forest\' and metrics was calculated. The index of bird assemblages used were composition and functional diversity and richness, calculated using morphological and habitat traits. Linear regression and mixed models were used to investigate relationships between landscape metrics and i) functional diversity and richness of forest birds (obj. 1) and ii) functional diversity, species richness and morphological traits of fruit-eater birds (obj. 2). The results showed that fragment area and core area were the most important traits to preserve the functions in bird assemblage, demonstrating the importance of big blocks of forest. To morphological changes, the decreasing on forest over was related to decreases on values of: body mass, hand-wing index and bill width. The reduction of these values can promote the dispersal of smaller seeds, reduction on dispersal of plants with big seed and decreases of area cover by seed rain.
9

Changing valuations of cultural ecosystem services along an urban-periurban gradient in Berlin / Qualitative and quantitative assessment

Riechers, Maraja 14 July 2015 (has links)
No description available.
10

Mestská zeleň a inštitucionálny rámec jej zabezpečovania / Urban green spaces and its institutional framework

Sukupová, Kristína January 2012 (has links)
The thesis Urban green spaces and its institutional framework attempts to analyze different cases of urban green spaces foundation and administration in which various public and private entities act. Based on these foundations it tries to come with an overview of the most important forms of provision of greenery in cities. Through research of available literature we came to the understanding that greenery in urban environments is not just a result of municipal service provided by a public authority but to its foundation, administration, financing and maintenance contribute also other entities. The overview created in the thesis is not exhaustive but can serve as an inspiration for various subjects at a time when local public authorities do not have sufficient resources to ensure satisfactory range and quality of public green.

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