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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

Methods for Control in the Synthesis of Structured Siloxane Architectures

Thompson, David B. January 2008 (has links)
<p> The advantageous properties of siloxanes find use in a wide range of applications. Unfortunately, the dynamic nature of silicones which is responsible for these properties is often a limitation in the controlled synthesis and modification of siloxane materials. Gaining greater control over these processes would allow for the synthesis of siloxane materials with more explicit structures, giving them a narrower range of properties and expanding application. Furthermore, the ability to synthesize more siloxane architectures with greater control would allow for an increased understanding of the relationship between structural features and physical properties.</p> <p> The synthesis of hydrosilane-rich siloxane elastomers and subsequent controlled modification, particularly with poly(ethylene oxide), is described. The effect of chain length and functionality (mono- or di-) was found to influence the morphology of grafted polymer. It was also possible to take advantage of the intrinsic properties of siloxanes to sequester hydrophilic moieties to the interior of the elastomer. Utilizing the same hydrosilane rich elastomers, a method for the independent modification of the interior and exterior of hydrosilane rich elastomers is presented. The careful selection of grafting moieties and solvents is used to provide or deny transport to the interior of the elastomer. This method is used to synthesize PEO modified elastomers with various subsequent internal modifications.</p> <p> A method for controlled synthesis of silicone-carbohydrate composites is also described. Utilizing bifunctional silane linkers, protected carbohydrates were functionalized with bulky diisopropyl hydrosilane groups before linkage to short and long silicones. Alternatively, the linker could first be joined to a silicone, followed by silylation of unprotected saccharides using the resultant hindered chlorosilane functional silicone. This method gave preferential silylation at primary hydroxyl groups.</p> <p> Finally, a method is presented for the synthesis of explicit branched siloxane architectures. The B(C6F5)3 catalyzed dehydrocarbonative coupling of hydrosilanes with alkoxysilanes was used to construct branched siloxane architectures in a stepwise fashion. High levels of control were available through manipulation of steric parameters: careful selection of starting materials and conditions allowed for the synthesis of explicit alkoxysilane functional branched siloxanes. These could be grafted to hydrosilane functional silicone polymers, or used to assemble explicit branched siloxanes. Further explorations demonstrated that the assembly process was not inhibited by the presence of organohalide- or alkene functional groups, allowing for the synthesis of functional siloxane moieties with explicit structures.</p> / Thesis / Doctor of Philosophy (PhD)
2

A comunidade fitoplanctônica nas represas Billings e Guarapiranga (região metropolitana de São Paulo) / The phytoplankton community in Billings and Guarapiranga reservoirs (São Paulo metropolitan area)

Nishimura, Paula Yuri 10 December 2012 (has links)
Reservatórios apresentam gradientes horizontal e vertical de fatores abióticos que controlam a dinâmica fitoplanctônica, resultando em uma marcada heterogeneidade espacial na produtividade fitoplanctônica. Portanto, o fitoplâncton é um importante objeto de estudo em reservatórios. Tradicionalmente, os estudos ecológicos com fitoplâncton partiam da análise da comunidade a partir de espécies ou grandes divisões taxonômicas, como classes. Com o avanço do conhecimento, surgiram novas abordagens para o estudo desta comunidade, como os grupos funcionais. Diversos autores propuseram metodologias de classificação de grupos funcionais, baseados em diferentes critérios, como fisiologia, ecologia e/ou morfologia. O objetivo geral do presente estudo foi investigar a estrutura da comunidade fitoplanctônica em relação às características ambientais em duas represas de abastecimento de água da Região Metropolitana de São Paulo, as represas Billings e Guarapiranga. Para atender aos objetivos específicos, diversos aspectos foram abordados, como os possíveis impactos da transposição de águas da represa Billings para a Guarapiranga, a utilização de grupos funcionais na detecção de padrões ambientais, a comparação de diferentes metodologias de agrupamentos funcionais do fitoplâncton, a ocorrência do dinoflagelado invasor Ceratium furcoides em reservatórios brasileiros e a heterogeneidade ambiental da represa Guarapiranga com base na qualidade da água e nas comunidades planctônicas. As represas Billings e Guarapiranga discriminaram-se quanto às variáveis físicas, químicas e biológicas, sendo classificadas como meso/eutróficas. A comunidade fitoplanctônica da represa Billings foi dominada pelo dinoflagelado invasor Ceratium furcoides (Lo), que provavelmente está sendo transferido para a represa Guarapiranga através do sistema de transposição. A baixa qualidade da água do ribeirão Parelheiros influenciou fortemente a qualidade da água da represa Guarapiranga, principalmente na região de entrada deste tributário, com domínio do grupo funcional LM. As regiões mais distantes da região de influência do ribeirão Parelheiros na represa Guarapiranga apresentaram condições distintas, devido à influência de tributários com melhor qualidade de água. Observou-se abundância de distintos grupos funcionais, como WS, H1 e A, evidenciando uma heterogeneidade da qualidade da água no eixo longitudinal da represa Guarapiranga. Três compartimentos principais foram identificados: 1) região do Embu-Guaçu, parte alta da represa, mais protegida e menos eutrófica dominada por fitoplâncton R-estrategista e rotíferos; 2) região do Parelheiros, um braço eutrófico da represa com domínio de fitoplâncton C-estrategista e elevada densidade de copépodes ciclopóidas e 3) parte baixa do reservatório, com características eutróficas e lacustrinas, co-dominância de fitoplâncton C e S-estrategistas e maior contribuição de copépodes à densidade total do zooplâncton. A adição do algicida sulfato de cobre na água da represa Guarapiranga influenciou a formação de compartimentos com base nas comunidades fitoplanctônica e zooplanctônica. Ao fim deste trabalho, evidenciou-se a importância 1) da preservação do ribeirão Parelheiros e do monitoramento da transferência de espécies fitoplanctônicas da represa Billings para a Guarapiranga visando a preservação da qualidade da água represa Guarapiranga, 2) da necessidade do monitoramento da ocorrência e dispersão de C. furcoides no Brasil, 3) da implementação de programas de manejo na represa Guarapiranga que levem em consideração a presença de heterogeneidade ambiental neste reservatório e 4) da utilização dos grupos funcionais fitoplanctônicos como ferramenta na identificação de padrões ambientais / Reservoirs exhibit horizontal and vertical gradients of abiotic factors that control phytoplankton dynamics, resulting in a marked spatial heterogeneity in phytoplankton productivity. Therefore, phytoplankton is an important object of study in reservoirs. Traditionally, ecological studies on phytoplankton community were based on species or taxonomic major divisions, such as classes. As science advanced, new approaches appeared, such as functional groups. Several authors have proposed methods of functional groups\' classification based on different criteria, such as physiology, ecology and/or morphology. The general objective of this study was to investigate the structure of the phytoplankton community in relation to environmental characteristics in two water supply reservoirs in São Paulo Metropolitan Area, Billings and Guarapiranga reservoirs. To reach some specific aims, several aspects were investigated: the possible impacts of the water transfer from Billings to Guarapiranga reservoir, the use of functional groups in the detection of environmental patterns, comparison of different methodologies of phytoplankton functional groups\' classification, the occurrence the invasive dinoflagellate Ceratium furcoides in Brazilian reservoirs and the environmental heterogeneity of Guarapiranga reservoir based on water quality and planktonic communities. Billings and Guarapiranga reservoirs exhibited distinct physical, chemical and biological characteristics, being both classified as meso/eutrophic. The phytoplankton community of Billings reservoir was dominated by C. furcoides (Lo), which is probably being transferred to Guarapiranga through the water transfer system. The poor water quality of the Parelheiros stream strongly influenced the water quality of Guarapiranga reservoir, mainly at the entrance of this tributary, with dominance of functional group LM. Regions further away from Parelheiros stream in Guarapiranga reservoir exhibited different conditions, due to the influence of tributaries with better water quality. It was observed abundance of different functional groups, such as WS, H1 and A, demonstrating the presence of water quality heterogeneity in the longitudinal axis of Guarapiranga reservoir. Three main compartments were identified: 1) Embu Guaçu region, upstream, more protected and less eutrophic, dominated by phytoplankton R-strategists and rotifers; 2) Parelheiros region, a eutrophic branch of the reservoir, dominated by phytoplankton C- strategists and high density of copepods cyclopoids and 3) the lower part of the reservoir, with eutrophic and lacustrine features, co-dominance of phytoplankton C and S-strategists and higher contribution of copepods to the total density of zooplankton. The addition of the algaecide copper sulfate in the reservoir\'s water influenced the formation of compartments based on phytoplankton and zooplankton communities. Some final remarks were highlighted at the end of this study: 1) the importance of the preservation of Parelheiros stream\'s water quality in order to maintain Guarapiranga reservoir water quality, 2) the transfer of phytoplankton species from Billings to Guarapiranga reservoir must be closely monitored, 3) the occurrence and dispersion of C. furcoides in Brazililian waters must be closely monitored, 4) management programs in Guarapiranga reservoir must take into account the presence of water quality heterogeneity and 5) phytoplankton functional groups as a tool for identifying environmental patterns should be applied
3

Theoretical synthesis of macromolecules from transferable functional groups /

Martín, Fernando J. January 2001 (has links)
Thesis (Ph.D.) -- McMaster University, 2001. / Includes bibliographical references (leaves 170-174).
4

A comunidade fitoplanctônica nas represas Billings e Guarapiranga (região metropolitana de São Paulo) / The phytoplankton community in Billings and Guarapiranga reservoirs (São Paulo metropolitan area)

Paula Yuri Nishimura 10 December 2012 (has links)
Reservatórios apresentam gradientes horizontal e vertical de fatores abióticos que controlam a dinâmica fitoplanctônica, resultando em uma marcada heterogeneidade espacial na produtividade fitoplanctônica. Portanto, o fitoplâncton é um importante objeto de estudo em reservatórios. Tradicionalmente, os estudos ecológicos com fitoplâncton partiam da análise da comunidade a partir de espécies ou grandes divisões taxonômicas, como classes. Com o avanço do conhecimento, surgiram novas abordagens para o estudo desta comunidade, como os grupos funcionais. Diversos autores propuseram metodologias de classificação de grupos funcionais, baseados em diferentes critérios, como fisiologia, ecologia e/ou morfologia. O objetivo geral do presente estudo foi investigar a estrutura da comunidade fitoplanctônica em relação às características ambientais em duas represas de abastecimento de água da Região Metropolitana de São Paulo, as represas Billings e Guarapiranga. Para atender aos objetivos específicos, diversos aspectos foram abordados, como os possíveis impactos da transposição de águas da represa Billings para a Guarapiranga, a utilização de grupos funcionais na detecção de padrões ambientais, a comparação de diferentes metodologias de agrupamentos funcionais do fitoplâncton, a ocorrência do dinoflagelado invasor Ceratium furcoides em reservatórios brasileiros e a heterogeneidade ambiental da represa Guarapiranga com base na qualidade da água e nas comunidades planctônicas. As represas Billings e Guarapiranga discriminaram-se quanto às variáveis físicas, químicas e biológicas, sendo classificadas como meso/eutróficas. A comunidade fitoplanctônica da represa Billings foi dominada pelo dinoflagelado invasor Ceratium furcoides (Lo), que provavelmente está sendo transferido para a represa Guarapiranga através do sistema de transposição. A baixa qualidade da água do ribeirão Parelheiros influenciou fortemente a qualidade da água da represa Guarapiranga, principalmente na região de entrada deste tributário, com domínio do grupo funcional LM. As regiões mais distantes da região de influência do ribeirão Parelheiros na represa Guarapiranga apresentaram condições distintas, devido à influência de tributários com melhor qualidade de água. Observou-se abundância de distintos grupos funcionais, como WS, H1 e A, evidenciando uma heterogeneidade da qualidade da água no eixo longitudinal da represa Guarapiranga. Três compartimentos principais foram identificados: 1) região do Embu-Guaçu, parte alta da represa, mais protegida e menos eutrófica dominada por fitoplâncton R-estrategista e rotíferos; 2) região do Parelheiros, um braço eutrófico da represa com domínio de fitoplâncton C-estrategista e elevada densidade de copépodes ciclopóidas e 3) parte baixa do reservatório, com características eutróficas e lacustrinas, co-dominância de fitoplâncton C e S-estrategistas e maior contribuição de copépodes à densidade total do zooplâncton. A adição do algicida sulfato de cobre na água da represa Guarapiranga influenciou a formação de compartimentos com base nas comunidades fitoplanctônica e zooplanctônica. Ao fim deste trabalho, evidenciou-se a importância 1) da preservação do ribeirão Parelheiros e do monitoramento da transferência de espécies fitoplanctônicas da represa Billings para a Guarapiranga visando a preservação da qualidade da água represa Guarapiranga, 2) da necessidade do monitoramento da ocorrência e dispersão de C. furcoides no Brasil, 3) da implementação de programas de manejo na represa Guarapiranga que levem em consideração a presença de heterogeneidade ambiental neste reservatório e 4) da utilização dos grupos funcionais fitoplanctônicos como ferramenta na identificação de padrões ambientais / Reservoirs exhibit horizontal and vertical gradients of abiotic factors that control phytoplankton dynamics, resulting in a marked spatial heterogeneity in phytoplankton productivity. Therefore, phytoplankton is an important object of study in reservoirs. Traditionally, ecological studies on phytoplankton community were based on species or taxonomic major divisions, such as classes. As science advanced, new approaches appeared, such as functional groups. Several authors have proposed methods of functional groups\' classification based on different criteria, such as physiology, ecology and/or morphology. The general objective of this study was to investigate the structure of the phytoplankton community in relation to environmental characteristics in two water supply reservoirs in São Paulo Metropolitan Area, Billings and Guarapiranga reservoirs. To reach some specific aims, several aspects were investigated: the possible impacts of the water transfer from Billings to Guarapiranga reservoir, the use of functional groups in the detection of environmental patterns, comparison of different methodologies of phytoplankton functional groups\' classification, the occurrence the invasive dinoflagellate Ceratium furcoides in Brazilian reservoirs and the environmental heterogeneity of Guarapiranga reservoir based on water quality and planktonic communities. Billings and Guarapiranga reservoirs exhibited distinct physical, chemical and biological characteristics, being both classified as meso/eutrophic. The phytoplankton community of Billings reservoir was dominated by C. furcoides (Lo), which is probably being transferred to Guarapiranga through the water transfer system. The poor water quality of the Parelheiros stream strongly influenced the water quality of Guarapiranga reservoir, mainly at the entrance of this tributary, with dominance of functional group LM. Regions further away from Parelheiros stream in Guarapiranga reservoir exhibited different conditions, due to the influence of tributaries with better water quality. It was observed abundance of different functional groups, such as WS, H1 and A, demonstrating the presence of water quality heterogeneity in the longitudinal axis of Guarapiranga reservoir. Three main compartments were identified: 1) Embu Guaçu region, upstream, more protected and less eutrophic, dominated by phytoplankton R-strategists and rotifers; 2) Parelheiros region, a eutrophic branch of the reservoir, dominated by phytoplankton C- strategists and high density of copepods cyclopoids and 3) the lower part of the reservoir, with eutrophic and lacustrine features, co-dominance of phytoplankton C and S-strategists and higher contribution of copepods to the total density of zooplankton. The addition of the algaecide copper sulfate in the reservoir\'s water influenced the formation of compartments based on phytoplankton and zooplankton communities. Some final remarks were highlighted at the end of this study: 1) the importance of the preservation of Parelheiros stream\'s water quality in order to maintain Guarapiranga reservoir water quality, 2) the transfer of phytoplankton species from Billings to Guarapiranga reservoir must be closely monitored, 3) the occurrence and dispersion of C. furcoides in Brazililian waters must be closely monitored, 4) management programs in Guarapiranga reservoir must take into account the presence of water quality heterogeneity and 5) phytoplankton functional groups as a tool for identifying environmental patterns should be applied
5

Living Polystyrene Anions Terminated with Difulvene

Li, Su 12 1900 (has links)
<p> This project proposal is focused on the development of a novel class of Viscosity Index improvers. A bench-top method for living anionic polymerization has been set up and tested in many aspects. A new difulvene derivative, 1,4-di(6'-6'-methyl-fulvyl)benzene, was synthesized. The living anionic polymer chain was terminated on this difulvene. Cyclopentadiene groups were formed in the middle of the macromolecule chain during the termination. A doubled molecular weight of polystyrene was obtained after the termination. The cyclopentadienes were then changed to other functional groups by Diels-Alder reaction with dimethyl acetylenedicarboxylate, ozonolysis of double bonds, and bromination and reaction with amine. The infrared spectra and nuclear magnetic resonance spectra of the resulting polymers showed new peaks for the new attached groups.</p> / Thesis / Master of Science (MSc)
6

6,6’-Dimethoxygossypol: Molecular Structure, Crystal Polymorphism, and Solvate Formation.

Zelaya, Carlos A. 20 May 2011 (has links)
6,6’-Dimethoxygossypol (DMG) is a natural product of the cotton variety Gossypium barbadense and a derivative of gossypol. Gossypol has been shown to form an abundant number of clathrates with a large variety of compounds. One of the primary reasons why gossypol can form clathrates has been because of its ability to from extensive hydrogen bonding networks due to its hydroxyl and aldehyde functional groups. Prior to this work, the only known solvate that DMG formed was with acetic acid. DMG has methoxy groups substituted at two hydroxyl positions, and consequently there is a decrease in its ability to form hydrogen bonds. Crystallization experiments were set up to see whether, like gossypol, DMG could form clathrates. The following results presented prove that DMG is capable of forming clathrates (S1 and S2) and two new polymorphs (P1 and P2) of DMG have been reported.
7

A Multi-Method Approach for the Quantification of Surface Amine Groups on Silica Nanoparticles

Sun, Ying 29 July 2019 (has links)
As nanomaterials continue to garner interest in a wide range of industries and scientific fields, commercial suppliers have met growing consumer demand by readily offering custom particles with size, shape and surface functionality made-to-order. By circumventing the challenging and complex synthesis of functionalized nanoparticles, these businesses seek to provide greater access for the experimentation and application of these nanoscale platforms. In many cases, amine functional groups are covalently attached as a surface coating on a nanoparticle to provide a starting point for chemical derivatization and commonly, conjugation of biomolecules in medical science applications. Successful conjugation can improve the compatibility, interfacing and activity of therapeutic and diagnostic nanomedicines. Amines are amongst the most popular reactive groups used in bioconjugation pathways owing to the many high-yield alkylation and acylation reaction are involved in. For the design of functionalized nanomaterials with precisely tuned surface chemical properties, it is important to develop techniques and methods which can accurately and reproducibly characterize these materials. Quantification of surface functional groups is crucial, as these groups not only allow for conjugation of chemical species, but they also influence the surface charge and therefore aggregation behavior of nanomaterials. The loss of colloidal stability of functionalized nanomaterials can often correspond to a significant if not complete loss of functionality. Thus, we sought to develop multiple characterization approaches for the quantification of surface amine groups. Silica nanoparticles were selected as a model nanomaterial as they are widely used, commercially available, and their surface chemistry has been investigated and studied for decades. Various commercial batches of silica nanoparticles were procured with sizes ranging from 20 – 120 nm. Two colorimetric assays were developed and adapted for their ease-of-use, sensitivity, and convenience. In addition, a fluorine labelling technique was developed which enabled analysis by quantitative solid-state 19F NMR and X-ray photoelectron spectroscopy (XPS). XPS provided data on surface chemical composition at a depth of ≈ 10 nm, which allowed us to determine coupling efficiencies of the fluorine labelling technique and evaluate the reactivity of the two assays. The ensemble of surface-specific quantification techniques was used to evaluate multiple commercial batches of aminated silica and investigate batch-to-batch variability and the influence of particle size with degree of functionalization. In addition, resulting measurements of surface amine content were compared and validated by an independent method based on quantitative solution 1H NMR, which was developed for total functional group content determination. This allowed for us to assess the role of accessibility and reactivity of the amine groups present in our silica particles. Overall, the objective of this study was to develop a multi-method approach for the quantification of amine functional groups on silica nanoparticles. At the same time, we hoped to set a precedent for the development and application of multiple characterization techniques with an emphasis of comparing them on the basis of reproducibility, sensitivity, and mutual validation.
8

Habitatets och funktionella gruppers respons ett år efter dammutrivning : Nianån och Gnarpsån / The response of the habitat and functional groups one year after dam removal : Nianån and Gnarpsån

Lindsten, Madeleine January 2019 (has links)
Dams are a typical example of how watercourses are being used, especially for production of electricity. Negative consequences that follows are that the character of the watercourse is altered, which in turn affects the composition of organisms. In the summer of 2017, a hydroelectric plant was removed in Nianån. A project started with the purpose to investigate the effects on benthic fauna, one year after the removal. In this study, the watercourse Gnarpsån was also used as a control. It was assumed that the proportion of silt and sand, as well as the water depth had decreased while the water velocity had increased in the habitat of the former reservoir in Nianån. It was also assumed that a change in the density of the benthic fauna should have occurred in Nianån, downstream in the riffle. The abundance of organisms with a burial lifestyle should have decreased in the habitat of the former reservoir, while the abundance of scrapers and filters should increase in the riffle. The result showed few significant physical changes. A difference in substrate composition could be seen in Nianån, however it was the proportion of fine substrates that increased in all habitats (gravel, fine gravel and sand). The water velocity was unchanged in Nianån, and the depth only decreased in the flowing habitat upstream. In both watercourses, 38 different families of macroinvertebrates were found. The proportion of burial animals in the habitat of the former reservoir decreased significantly, but no change in the total density was found. A possible effect may already have been recovered, or more time may need to pass before expected results can be seen. Many factors affect the conditions in the watercourses. To be able to provide better general predictions about the effects of dam removal, further studies are needed, both at the organism level and with a large-scale approach to get a uniform picture of this restoration measure. / Dammar är typiska exempel på hur vattendrag utnyttjas, framförallt för elproduktion. Negativa följder är att vattendragets karaktär förändras, vilket i sin tur påverkar sammansättningen av organismer. Sommaren 2017 togs ett kraftverk bort i Nianån. Ett projekt startade med syftet att undersöka effekterna på bentisk fauna ett år efter dammutrivningen. I denna studie används också vattendraget Gnarpsån som en kontroll. Det antogs att andelen silt och sand, samt vattendjupet hade minskat medan vattenhastigheten hade ökat i habitatet i den före detta regleringsdammen i Nianån. Det antogs även att en förändring av tätheten av bottenfauna borde ha skett i Nianån, nedströms i torrfåran. Andelen nedgrävande djur borde ha minskat i habitatet i den före detta regleringsdammen, medan andelen skrapare och filtrerare ökat i torrfåran. Resultatet visade på få signifikanta fysiska förändringar. En viss skillnad i substratsammansättning kunde ses i Nianån, dock var det andelen fint substrat som ökat i samtliga habitat (grus, fint grus och sand). Vattenhastigheten var oförändrad i Nianån, och djupet minskade endast i det strömmande habitatet uppströms. I vattendragen återfanns 38 olika familjer av makroevertebrater. Andelen nedgrävande djur i habitatet i den före detta regleringsdammen minskade signifikant, men någon förändring i total individtäthet påvisades inte. En eventuell effekt kan redan ha återhämtats, eller så behöver mer tid gå innan förväntade resultat kan ses. Många faktorer påverkar förhållandena i vattendragen. För att kunna ge bättre generella förutsägningar om effekter av dammutrivning behövs vidare studier, både på organismnivå och med ett storskaligt synsätt för att få en enhetlig bild över denna restaureringsåtgärd.
9

Riqueza e composição das comunidades de formigas em quatro formas de cultivo de erva-mate (Ilex Paraguariensis St. Hil., 1822) na Encosta Superior do Nordeste do Rio Grande do Sul

Steffens, Luiz Eduardo 31 May 2006 (has links)
Submitted by JOSIANE SANTOS DE OLIVEIRA (josianeso) on 2018-04-26T16:24:39Z No. of bitstreams: 1 Luiz Eduardo Steffens_.pdf: 2734317 bytes, checksum: 7ce3824925bb95a8b45268be640b5233 (MD5) / Made available in DSpace on 2018-04-26T16:24:39Z (GMT). No. of bitstreams: 1 Luiz Eduardo Steffens_.pdf: 2734317 bytes, checksum: 7ce3824925bb95a8b45268be640b5233 (MD5) Previous issue date: 2006-05-31 / UNISINOS - Universidade do Vale do Rio dos Sinos / No Rio Grande do Sul, a erva-mate, Ilex paraguariensis St. Hil. (Aquifoliaceae), é um dos componentes nativos da floresta ombrófila mista e tem importância sócio-econômica e ambiental. Este trabalho objetivou inventariar e comparar a riqueza e composição de táxons de formigas em quatro formas de cultivo de erva-mate: nativa, consorciada, monocultivo com e sem aplicação de herbicida e determinar os padrões de ocorrência e de dominância, e o status dos táxons. Durante 12 meses, em cada forma de cultivo, foram amostradas aleatoriamente dez árvores, utilizando-se guarda-chuva entomológico com esforço amostral de 20 batidas por erveira. Paralelamente, com a rede entomológica de varredura foram feitas coletas na vegetação entre as erveiras com 100 redadas por forma de cultivo. Dos 35 táxons registrados, 27 foram encontrados nos ervais nativos, 26 nos monocultivos com aplicação de herbicida, 19 nos de monocultivo e 18 nos ervais consorciados. Quatorze (40,0 %) foram comuns a todas as formas de cultivo, seis (17,1 %) foram exclusivos no cultivo nativo, quatro (11,4 %) no erval com aplicação de herbicida e tanto o erval consorciado, quanto o monocultivo apresentaram apenas um táxon (2,8 %) exclusivo. Ocorreu diferença significativa (p=0,031) apenas entre as comunidades de formigas dos ervais nativo e consorciado. A subfamília melhor representada foi Myrmicinae com 17 gêneros. A similaridade entre as comunidades de formigas dos ervais com aplicação de herbicida e monocultivo foi a mais alta (Sj=71,8 %). A maioria dos táxons foi categorizada como acidental e dominante, com status intermediário. A distribuição dos grupos funcionais apresentou grande semelhança entre as quatro comunidades, sugerindo que a forma de cultivo interfere mais sobre a riqueza de táxons do que sobre a estrutura funcional das comunidades de formigas. / In the Rio Grande do Sul State, the maté, Ilex paraguariensis St. Hil. (Aquifoliaceae), is one of the main native components of the mixed ombrophilous forest understory with social-economical and environmental value. The present study aimed at surveying and comparing the ant species richness and composition among four differently cultivated maté fields: native, intercropping system, monoculture and herbicide treated, determining the occurrence and the dominance patterns and the species status. In each fields, ten maté trees were randomly sampled during 12 months using beating tray with a sample effort of 20 beatings per tree. At the same time, 100 sweeps using the entomologic net sampled the vegetation between the maté trees per field. Of the 35 taxa collected, 27 occurred in the native fields, 26 in the herbicide treated fields, 19 in the monoculture and 18 taxa in the mixed culture fields. Fourteen (40.0 %) were common to all cultivation techniques, six (17.1 %) were exclusive to the native fields and four (11.4 %) in the herbicide treated fields. A single exclusive taxon (2.8 %) occurred in the areas of herbicide treatment, mixed culture and monoculture. The native field differed significantly (p=0.031) from the mixed one. The subfamily Myrmicinae was the most representative with 17 genera. The herbicide treated and the monoculture fields had the highest similarity (Sj=71.8 %). Most of the species status was categorized as accidental, dominant and as intermediate. The functional groups distribution presented great similarity among the four ant communities, suggesting that the cultivation form interferes more on the wealth of species than on the functional structure of the ants.
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Diversidade de aranhas (ARACHNIDA: ARANEAE) em áreas de campos sulinos, de domínio dos Biomas Pampa e Mata Atlântica

Marta, Kimberly da Silva January 2017 (has links)
Os Campos Sulinos são uma fisionomia de vegetação encontrada no Sul do Brasil. Integram dois Biomas brasileiros, sendo eles a Mata Atlântica e o Pampa. Desenvolvem-se em clima temperado e úmido, com chuvas bem distribuídas ao longo do ano. Abrigam muitas espécies vegetais e apresentam uma fauna diversa, com grande número de espécies endêmicas da região. Na América do Sul, os campos e/ou pampas se estendem por uma área de aproximadamente 750 mil km², compartilhada por Brasil, Uruguai e Argentina e parte do Paraguai. No Brasil, o bioma Pampa está restrito ao Rio Grande do Sul, onde ocupa 178.243 km². Ainda que o clima atual favoreça expansões de florestas sobre os campos, muitos fatores interagem para definir se o campo ou a floresta irão se estabelecer num determinado local. Ambos são estados ecossistêmicos estáveis que coexistem, com um grau variável de tensão. Restam apenas 50% da área original de campos no Rio Grande do Sul, por conta de distúrbios antropogênicos, como a agricultura, silvicultura, pecuária extensiva (através do pastejo) e queimadas. A perda de hábitat é acompanhada da fragmentação dos remanescentes e da invasão por espécies exóticas, sendo a conservação desses campos negligenciada já de longa data. Sabe-se atualmente que, em alguns trabalhos, a vegetação e fauna pode ser restabelecida ou mantida após alguns tipos de distúrbios e ambas têm uma forte correlação. Aranhas parecem ser bons modelos para o entendimento da funcionalidade desses ecossistemas. Esse táxon é o sétimo maior em termos de riqueza, atualmente tem descritas cerca de 46 mil espécies e pouco se sabe sobre essa diversidade nos Campos Sulinos. O trabalho teve como objetivos o conhecimento acerca da diversidade (riqueza de espécies, abundância, composição) e a função desses organismos (através de guildas e atributos funcionais) para realizarmos comparações dessa diversidade funcional entre as fisionomias vegetais encontradas nos dois Biomas. Foram selecionadas oito áreas de estudo, sendo cinco delas incluídas no Bioma Pampa e três no Bioma Mata Atlântica. O método empregado para coleta dos indivíduos foi o de D-Vac. Os municípios tiveram apenas uma réplica e foram coletados em estações diferentes. Comparações com cluster de Jaccard e Bray-Curtis foram realizados para o entendimento de correlação das fisionomias vegetais encontradas e os índices de diversidade encontrado para cada área. Agrupamentos de Pampa e Mata Atlântica foram formados, nos mostrando que existe sim uma similaridade da diversidade de aranhas quando relacionada com a vegetação. Apesar dessas análises nos revelarem agrupamentos, o teste de ANOSIM com índices de Jaccard e Morisita não revelaram diferenças significativas, mas apresentaram quando testados com o índice de Bray-Curtis. As curvas de rarefação nos mostram que ainda existe a necessidade de um esforço maior para termos a compreensão da diversidade existente para os campos. Quando refinamos as análises e inserimos os grupos funcionais (aqui considerados guildas) para continuar a descrever esse ecossistema, o resultado pode continuar a ser corroborado, nos trazendo novas evidências de diferenças entre os biomas. As aranhas tiveram quatro atributos morfológicos mensurados, sendo o comprimento total do indivíduo, o comprimento do abdômen, a largura do abdômen e o comprimento da patela e tíbia da perna I. Esses atributos posteriormente foram relacionados com as guildas de aranhas e testados também referente ao sexo. Todos os testes foram realizados através de Teste de MannWhiteney, pois os dados não seguiam uma distribuição normal e todos tiveram uma resposta significativa. Quando realizada a MANOVA que lidou com as diferentes variáveiss abióticas e bióticas de cada município, como: localidade/fitofisionomia, estação, guildas, sexo, obtivemos respostas não significativas apenas quando testadas Estação por Sexo, com p=0.3758 e Localidade por Sexo p=1. Quando analisados Localidades por Guildas (p=0.0002), Localidade por Sexo (p= 0.0025); Estação por Guildas (p=0.0002) e Guildas por Sexo (p=0.0002) todos os valores de P foram significativos. Apesar de já termos bastante diferenças significativas entre as áreas de estudos, estudos futuros se fazem necessários. Sugere-se que o uso de atributos funcionais seja utilizado com uma abrangência maior para futuramente poder utilizar esse dado morfométrico como descritores de guildas, e consequentemente sugere-se fortemente o uso de análise separada para os sexos, visto que estes organismos apresentam uma alta variabilidade dimorfismo sexual e seleção sexual através de atributos morfológicos. Conseguimos por fim, aceitar nossa hipótese inicial que era tentar separar a diversidade de aranhas para os Campos Sulinos, através dos descritores ambientais e as variáveis bióticas. / The Southern Fields (SC, PR and RS) are a physiognomy of vegetation found in southern Brazil. They integrate two Brazilian Biomes, being them the Atlantic Forest and the Pampa Biome (grasslands). They develop in temperate and humid climate, with rains well distributed throughout the year. They shelter many plant species and they present a diverse fauna, with great number of endemic species of the region. In South America, the fields extend over an area of approximately 750,000 km², shared by Brazil, Uruguay and Argentina and part of Paraguay. In Brazil, the Pampa biome is restricted to Rio Grande do Sul, where it occupies 178,243 km². Although the current climate favors forest expansions over fields, many factors interact to define whether the field or forest will settle in a particular location. Both are stable ecosystem states that coexist, with a varying degree of tension. Only 50% of the original field area remains in Rio Grande do Sul because of anthropogenic disturbances such as agriculture, forestry, extensive cattle grazing (through grazing) and fires. Habitat loss is accompanied by the fragmentation of remnants and invasion by exotic species, and the conservation of these fields has long been neglected. It is now known that in some studies, vegetation and fauna can be reestablished or maintained after some types of disturbances and both have a strong correlation. Spiders appear to be good models for understanding the functionality of these ecosystems. This taxon is the seventh largest in terms of wealth, currently has described about 46 thousand species and little is known about this diversity in the Southern Fields. The objective of this work was to know the diversity (richness of species, abundance, composition) and the function of these organisms (through guilds and functional attributes) to make comparisons of this functional diversity between the vegetation physiognomies found in the two Biomes. Eight study areas were selected, five of them included in the Pampa Biome and three in the Atlantic Forest. The method used to collect individuals was D-Vac. The municipalities had only one replica and were collected at different stations. Comparisons with Jaccard and Bray-Curtis clusters were performed to understand the corelation of the vegetation physiognomies found and the diversity indexes found for each area. Clusters of 12 Pampa and Atlantic Forest were formed, showing that there is a similarity of spider diversity when related to vegetation. Although these analyzes reveal groupings, the ANOSIM test with Jaccard and Morisita indices revealed no significant differences, but they did present when tested with the Bray-Curtis index. The rarefaction curves show us that there is still a need for a greater effort to compete the diversity of the fields. When we refine the analyzes and insert the functional groups (here considered guilds) to continue to describe this ecosystem, the result can continue to be corroborated, bringing us new evidence of differences between the Biomes. The spiders had four morphological attributes measured, being the total length of the individual, the length of the abdomen, the width of the abdomen and the length of the patella and tibia of leg I. These attributes were later related to the spider guilds and also tested for the sex. All tests were performed using the Mann-Whiteney Test, as the data did not follow a normal distribution and all had a significant response. When performed MANOVA that dealt with the different abiotic and biotic variables of each municipality, such as: locality / phytophysiognomy, station, guilds, sex, we obtained non-significant responses only when tested by Sex Station, with p = 0.3758 and Place by Sex p = 1. When analyzed by Guilds (p = 0.0002), Place by Sex (p = 0.0025); Station by Guilds (p = 0.0002) and Guilds by Sex (p = 0.0002) all P values were significant. Although we already have significant differences between the study areas, future studies are necessary. It is suggested that the use of functional attributes be used with a greater abraction to be able to use this morphometric data as guild descriptors in the future, and consequently strongly suggests the use of separate analysis for the sexes, since these organisms present a high variability Sexual dimorphism and sexual selection through morphological attributes. We finally managed to accept our initial hypothesis which was to try to separate the spider diversity for the Southern Fields, through the environmental descriptors and the biotic variables.

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