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14C Dating of Tufa Deposits Around Lake Nam CO, Tibet林, 誠司, 白河, 知恵, 三石, 真祐瞳, 小澤, 和浩, 森, 宏, 中村, 俊夫, ウォリス, サイモン, Hayashi, Seiji, Shirakawa, Chie, Mitsuishi, Mayumi, Ozawa, Kazuhiro, Mori, Hiroshi, Nakamura, Toshio, Wallis, Simon 03 1900 (has links)
第23回名古屋大学年代測定総合研究センターシンポジウム平成22(2010)年度報告
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Avaliação da universalidade de primers de marcadores moleculares para aplicação na classe Chlorophyceae (Chlorophyta)Vieira, Helena Henriques 30 May 2014 (has links)
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Previous issue date: 2014-05-30 / Financiadora de Estudos e Projetos / The polifasic taxonomy approach became indispensable in classification of living beings, especially microorganisms, such as Chlorophyceae. This class is compound of very distinct organisms most microscopic, unicellular, colonials, filamentous, and the classification and identification is many times hampered due the lack of structures observable that helps the discrimination. Some habits, reproduction, the occurrence of cryptic species are some factors that can lead to forms that make difficult the taxonomy of these organisms. Besides the traditional morphology, the molecular biology allows a robust concerning the classification of the studied organism. Associated to a better classification, the search for faster and more practical methods of identification, as DNA Barcode, became intensified and many molecular markers are available in literature to be tested. For some groups of animals, brown algae, red algae and diatoms the marker COXI is considered an official DNA Barcode. However other groups, as Chlorophycea, are under constant investigation, due the fact that molecular marker that can be used satisfactory as DNA Barcode have not been found yet. Plastid markers as tufA, rbcL and nuclear as ITS are some of the most proposed to be applied in green algae, often combined with each other or other markers. However, for act as a molecular marker, it is necessary to be amplified by primers broadly applied. The present study has tested primers for tufA, ITS and rbcL marker, available in literature and already in use in other groups, looking for universality in Chlorophyceae. We also tested proposed universal primers for Chlorophyta (UCP4). Moreover, preliminary analyses have been performed for application of the markers as barcode in the class. The primers used for tufA marker showed universality in Chlorophycea amplifying for all 22 strains tested and sequencing have failed only for Oedogonium strain. From the rbcL marker, the primer pair GrbcL has amplified 12 and sequenced 7 of 22 strains and rbcLFP which one the reverse primer was designed in this study amplified and sequenced 16 lineages. Primers from the ITS marker amplified only 5 lineages and UCP4 primers have not amplified any strain. Beside the universality found for tufA primers, Analysis with the obtained sequences showed that the tufA gene is a promising molecular marker to be applied in Chlorophyceae. / A abordagem polifásica de taxonomia se tornou indispensável na classificação especialmente de microorganismos, como os da classe Chlorophyceae. Esta classe é composta de organismos muito distintos, sendo a maioria microscópica, apresentando formação do talo unicelular, colonial e filamentosa e a classificação e identificação dos representantes desta classe são muitas vezes dificultadas pelo fato de não possuírem estruturas observáveis em microscópio usadas para discriminação. Alguns hábitos e tipos de reprodução, a ocorrência de espécies crípticas são alguns fatores que podem resultar em formas que também dificultam a taxonomia destes organismos. Associada a uma classificação mais robusta, a procura por métodos mais rápidos e práticos, como o DNA Barcode, se intensificou e muitos marcadores moleculares já se encontram disponíveis na literatura para serem testados. Para alguns grupos de animais, algas pardas, algas vermelhas e diatomáceas o marcador COXI é considerado oficial como DNA Barcode. Entretanto, outros grupos como Chlorophyceae este marcador não é aplicável devido a sua natureza conservada e, portanto, estão sob constante investigação, devido ao fato de que ainda não foram encontrados marcadores que possam ser aplicados satisfatoriamente como DNA Barcode. Marcadores plastidiais como tufA, rbcL e nucleares como o ITS são alguns dos mais aplicados em estudos com algas verdes, muitas vezes combinados entre si ou com outros marcadores. Entretanto para que figurem como marcadores moleculares devem ser amplificados por primers que possam ser aplicados de maneira ampla. Assim, o presente estudo teve como objetivo testar primers para os marcadores tufA, ITS, rbcL , disponíveis na literatura e já aplicados com outros grupos, buscando a universalidade destes primers também em Chlorophyceae. Foi testado também um par de primers proposto como universal para Chlorophyta (UCP4). Os primers para o gene tufA mostraram universalidade para a classe amplificando todas as 22 cepas testadas com falha no seqüenciamento apenas para a cepa de Oedogonium sp.Os primers para o gene rbcL, GrbcL, amplificou 12 e seqüenciou satisfatoriamente 7 cepas das 22 utilizadas, e o par rbcLFP, o qual teve um de seus iniciadores desenhado neste estudo, amplificou e seqüenciou 16 cepas. Primers para o gene ITS amplificaram 5 cepas com bom seqüenciamento de apenas 3 e o par de primers UCP4 não amplificou nenhuma cepa. Além da universalidade observada do par de primers para o gene tufA, análises com as seqüências obtidas mostraram que este gene se mostrou um promissor candidato a marcado molecular para aplicação na classe Chlorophyceae.
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Assessing the Preservation Potential of Biogenic Features in Pre-Neogene Tufas and Travertines – Applications to ExobiologyRichardson, Justin 03 June 2005 (has links)
No description available.
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Diversidade de macroalgas da Baía do Almirantado, ilha Rei George, Península Antártica, baseada em 'DNA barcoding' e outros marcadores moleculares / Macroalgae diversity of admiralty bay, King George Island, Antarctic Peninsula based on DNA Barcoding and other molecular markersMedeiros, Amanda da Silva 22 October 2013 (has links)
Baseado em estudos morfológicos, as macroalgas marinhas da Baía do Almirantado (Ilha Rei George, Península Antártica) estão representadas por 55 táxons, sendo 30 Rhodophyta, 16 Phaeophyceae e 9 Chlorophyta. Recentemente foi proposta a utilização de 'DNA barcode' para uma rápida e acurada identificação de espécies de macroalgas. Sendo a região 5\' do gene mitocondrial cox 1utilizado para identificação de algas vermelhas e pardas; o gene plastidial tufA utilizado na identificação de algas verdes; e o domínio V do gene 23S rRNA - UPA, universal plastid amplicon, utilizado na identificação de organismos fotossintetizantes. O objetivo desse trabalho foi obter sequências do tipo 'DNA barcodes' e de outros marcadores filogenéticos para a formação do primeiro banco de dados moleculares para as macroalgas da Baía do Almirantado, Antártica. Cerca de 100 espécimes de macroalgas foram coletados, em diversos pontos da baía, durante as OPERANTARes XXV e XXIX, que ocorreram durante dezembro de 2006 a junho de 2007 e dezembro de 2010 a janeiro de 2011, respectivamente. No presente trabalho, foi obtido um total de 209 sequências, cobrindo 29 espécies das 55 citadas para o local, sendo que 157 sequências são para marcadores moleculares do tipo 'DNA barcode', das quais 95 sequências são para o marcador do cloroplasto UPA, 39 sequências para o marcador mitocondrial cox1 e 23 sequências para o tufA. As sequências consenso dos 'DNA barcodes' foram submetidas à análise de distância para determinar os agrupamentos genéticos. Após a análise dos agrupamentos obtidos para os 'DNA barcodes', foram selecionados espécimes, representando cada táxon, para o sequenciamento dos marcadores filogenéticos rbcL, SSU ou ITS totalizando 52 sequências. Neste estudo, foram obtidos dados moleculares para 8 espécies de Chlorophyta, 9 espécies de Phaeophyceae e 14 espécies de Rhodophyta. Entre as espécies de Chlorophyta, Prasiola sp. e Protomonostroma rosulatum (citada anteriormente como P. undulatum), de Phaeophyceae Chordaria linearis e as Rhodophyta Acanthococcus antarticus, Plumariopsis peninsularis e Callophyllis sp. (citada anteriormente como Callophyllis atrosanguinea) são novas citações para a Baía do Almirantado. Sendo que a espécie Callophyllis sp. é possivelmente uma nova espécie. Outras duas espécies previamente citadas, baseado nos resultados moleculares, não ocorrem no local, Desmarestia chordalis e Pyropia woolhousiae. Com os resultados obtidos neste trabalho o número de espécies que ocorrem na Baía do Almirantado passa a 57 táxons / Based on morphological studies, the marine macroalgae of Admiralty Bay ( King George Island , Antarctic Peninsula ) are represented by 55 taxa: 30 Rhodophyta, 16 Phaeophyceae and 9 Chlorophyta. It was recently proposed the use of DNA barcodes for quick and accurate identification of seaweeds. The 5\' end region of mitochondrial cox1 gene is used to identify brown and red algae, the plastid gene tufA is used in identifying green algae, and the V domain of the 23S rRNA gene - UPA universal plastid amplicon is used to identify photosynthetic organisms in general. The aim of this study was to obtain sequences of DNA barcodes and other phylogenetic markers for the formation of the first molecular database for macroalgae of Admiralty Bay, Antarctica. About 100 specimens of macroalgae were collected at various points of the bay during the OPERANTARs XXV and XXIX , which occurred during December 2006 to June 2007 and December 2010 and January 2011 respectively. In this study, we obtained a total of 209 sequences, covering 29 of the 55 species cited for the site. Of those 157 sequences are DNA barcodes, of which 95 are for the marker sequences of chloroplast UPA, 39 sequences for the mitochondrial markercox1 and 23 sequences for the tufA. The consensus sequences of the DNA barcodes were subjected to distance analysis to determine the genetic groupings.After analyzing the clusters obtained for the DNA barcodes, specimens representing each taxon were selected to the sequencing of phylogenetic markers rbcL, SSU and/or ITS sequences totaling 52 sequences for those markers. In this study, molecular data were obtained for 8 species of Chlorophyta , 9 species of Phaeophyceae and 14 species of Rhodophyta. Among the Chlorophyta species, Prasiola sp. and Protomonostroma rosulatum> (previously cited as P. undulatum), the Phaeophyceae Chordaria linearis and the Rhodophyta Acanthococcus antarticus, Plumariopsis peninsularis and Callophyllis sp. (previously cited as Callophyllis atrosanguinea) are new records for the Admiralty Bay. And the species Callophyllis sp. is possibly a new species. Other two species previously mentioned, based on molecular results, Desmarestia chordalis and Pyropia woolhousiae do not occur at the site. With the results obtained in this work the number of species that occur in Admiralty Bay are of 57 taxa.
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Diversidade de macroalgas da Baía do Almirantado, ilha Rei George, Península Antártica, baseada em 'DNA barcoding' e outros marcadores moleculares / Macroalgae diversity of admiralty bay, King George Island, Antarctic Peninsula based on DNA Barcoding and other molecular markersAmanda da Silva Medeiros 22 October 2013 (has links)
Baseado em estudos morfológicos, as macroalgas marinhas da Baía do Almirantado (Ilha Rei George, Península Antártica) estão representadas por 55 táxons, sendo 30 Rhodophyta, 16 Phaeophyceae e 9 Chlorophyta. Recentemente foi proposta a utilização de 'DNA barcode' para uma rápida e acurada identificação de espécies de macroalgas. Sendo a região 5\' do gene mitocondrial cox 1utilizado para identificação de algas vermelhas e pardas; o gene plastidial tufA utilizado na identificação de algas verdes; e o domínio V do gene 23S rRNA - UPA, universal plastid amplicon, utilizado na identificação de organismos fotossintetizantes. O objetivo desse trabalho foi obter sequências do tipo 'DNA barcodes' e de outros marcadores filogenéticos para a formação do primeiro banco de dados moleculares para as macroalgas da Baía do Almirantado, Antártica. Cerca de 100 espécimes de macroalgas foram coletados, em diversos pontos da baía, durante as OPERANTARes XXV e XXIX, que ocorreram durante dezembro de 2006 a junho de 2007 e dezembro de 2010 a janeiro de 2011, respectivamente. No presente trabalho, foi obtido um total de 209 sequências, cobrindo 29 espécies das 55 citadas para o local, sendo que 157 sequências são para marcadores moleculares do tipo 'DNA barcode', das quais 95 sequências são para o marcador do cloroplasto UPA, 39 sequências para o marcador mitocondrial cox1 e 23 sequências para o tufA. As sequências consenso dos 'DNA barcodes' foram submetidas à análise de distância para determinar os agrupamentos genéticos. Após a análise dos agrupamentos obtidos para os 'DNA barcodes', foram selecionados espécimes, representando cada táxon, para o sequenciamento dos marcadores filogenéticos rbcL, SSU ou ITS totalizando 52 sequências. Neste estudo, foram obtidos dados moleculares para 8 espécies de Chlorophyta, 9 espécies de Phaeophyceae e 14 espécies de Rhodophyta. Entre as espécies de Chlorophyta, Prasiola sp. e Protomonostroma rosulatum (citada anteriormente como P. undulatum), de Phaeophyceae Chordaria linearis e as Rhodophyta Acanthococcus antarticus, Plumariopsis peninsularis e Callophyllis sp. (citada anteriormente como Callophyllis atrosanguinea) são novas citações para a Baía do Almirantado. Sendo que a espécie Callophyllis sp. é possivelmente uma nova espécie. Outras duas espécies previamente citadas, baseado nos resultados moleculares, não ocorrem no local, Desmarestia chordalis e Pyropia woolhousiae. Com os resultados obtidos neste trabalho o número de espécies que ocorrem na Baía do Almirantado passa a 57 táxons / Based on morphological studies, the marine macroalgae of Admiralty Bay ( King George Island , Antarctic Peninsula ) are represented by 55 taxa: 30 Rhodophyta, 16 Phaeophyceae and 9 Chlorophyta. It was recently proposed the use of DNA barcodes for quick and accurate identification of seaweeds. The 5\' end region of mitochondrial cox1 gene is used to identify brown and red algae, the plastid gene tufA is used in identifying green algae, and the V domain of the 23S rRNA gene - UPA universal plastid amplicon is used to identify photosynthetic organisms in general. The aim of this study was to obtain sequences of DNA barcodes and other phylogenetic markers for the formation of the first molecular database for macroalgae of Admiralty Bay, Antarctica. About 100 specimens of macroalgae were collected at various points of the bay during the OPERANTARs XXV and XXIX , which occurred during December 2006 to June 2007 and December 2010 and January 2011 respectively. In this study, we obtained a total of 209 sequences, covering 29 of the 55 species cited for the site. Of those 157 sequences are DNA barcodes, of which 95 are for the marker sequences of chloroplast UPA, 39 sequences for the mitochondrial markercox1 and 23 sequences for the tufA. The consensus sequences of the DNA barcodes were subjected to distance analysis to determine the genetic groupings.After analyzing the clusters obtained for the DNA barcodes, specimens representing each taxon were selected to the sequencing of phylogenetic markers rbcL, SSU and/or ITS sequences totaling 52 sequences for those markers. In this study, molecular data were obtained for 8 species of Chlorophyta , 9 species of Phaeophyceae and 14 species of Rhodophyta. Among the Chlorophyta species, Prasiola sp. and Protomonostroma rosulatum> (previously cited as P. undulatum), the Phaeophyceae Chordaria linearis and the Rhodophyta Acanthococcus antarticus, Plumariopsis peninsularis and Callophyllis sp. (previously cited as Callophyllis atrosanguinea) are new records for the Admiralty Bay. And the species Callophyllis sp. is possibly a new species. Other two species previously mentioned, based on molecular results, Desmarestia chordalis and Pyropia woolhousiae do not occur at the site. With the results obtained in this work the number of species that occur in Admiralty Bay are of 57 taxa.
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Architecture et distribution des systemes carbonatés se développant autour des sources hydrothermales : cas d’étude du basin de Denizli (Turquie), de la region de Rapolano (Italie) et de Mammoth Hot Springs (Wyoming, USA) / Architecture and occurrence of geothermal spring carbonates : case studies of the Denizli Basin (Turkey), the Rapolano region (Italy) and Mammoth Hot Springs (Wyoming, USA)Lopez, Benjamin 30 June 2015 (has links)
Les carbonates de sources hydrothermales (ou Geothermal Spring Carbonate, GSC) sont des systèmes carbonatés qui se développent autour de sources dont les eaux ont circulé en profondeur et sont remontées le long de failles perméables. Leur développement est contrôlé en tout premier lieu par la nature des eaux souterraines auxquelles ils sont liés. La formation de ces carbonates dépend d’interactions complexes entre les processus hydrologiques, tectoniques et structuraux se produisant avant l’émergence. Par la suite, la sédimentation est régie par de nombreux processus résultant des variations hydrologiques et chimiques de l’eau ainsi que par l’activité biologique. Du fait des interactions complexes entre ces facteurs, la sédimentation est sensible à de faible variations environnementales et il en résulte ainsi un grand nombre d’environnement de dépôts et de lithofacies.Le but de cette étude est d’améliorer les connaissances et les concepts fondamentaux propres au développement des carbonates de sources hydrothermales (GSC). Pour cela, elle s’appuie principalement sur l’examen des faciès que ce soit à petite échelle, comme l’observation des microstructures (microfabrics), ou à grande échelle, comme leur agencement en trois dimensions. De tels examens ont été effectués dans des sites hydrothermaux où ces carbonates se sont développés au cours du Quaternaire (région de Rapolano en Italie, bassin de Denizli en Turquie ou encore le Parc du Yellowstone dans le Wyoming, USA). / Geothermal spring carbonate (GSC) corresponds to a complex carbonate system formed around carbonate-rich springs fed by rising groundwaters along permeable fault zones. Their development is mainly controlled by the nature of springwaters emerging above water table. Therefore carbonate deposition is, in this setting, intimately related to complex interactions between hydrological, tectonic and structural processes occurring prior to water emergence. Moreover, carbonate sedimentation from springwater results from sedimentary processes controlled by complex interactions between hydrological, chemical characteristics and biological activity. Such processes are sensitive to slight environmental variations and thus lead to a large spectrum of lithofacies and ecosystems.The aim of this study is to improve knowledge and fundamental concepts regarding development of geothermal spring carbonates. For that purpose, lithofacies investigation, from microfabrics at micro-scale to 3-dimensional configuration at field-scale, is considered as an essential tool. Such investigations had been carried out in sites where Quaternary and actively forming GSCs were abundant (e.g. Rapolano region, Italy, Denizli Basin, Turkey and Yellowstone National Park, Wyoming, USA).
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Tufas calcárias da Serra da Bodoquena, MS / \"Calcareous tufa from Bodoquena\'s Ridge, MS\"Oliveira, Emiliano Castro de 13 April 2009 (has links)
Aflorando abundantemente nas drenagens da Serra da Bodoquena, região sudoeste do Estado de Mato Grosso do Sul, os depósitos de tufas calcárias, descritos como a porção superior da Formação Xaraiés, representam o mais notável depósito do tipo no Brasil, devido à variedade de formas. Sendo a maior atração do pólo eco-turístico de Bonito, MS, as tufas calcárias apresentam-se sob formas de barragens, cachoeiras e depósitos de micritos inconsolidados, que por sua vez geram as piscinas naturais e quedas dágua tão procuradas pelos turistas. Mesmo com tamanha importância, tal rocha não havia recebido um estudo aprofundando, que contemplasse sedimentologia, estratigrafia e geomorfologia. Através de criteriosa revisão bibliográfica, trabalhos em campo e análises laboratoriais, pôde-se obter um panorama da Formação Xaraiés na Serra da Bodoquena. Nesta região, observa-se que a formação, assentada diretamente sobre os calcários e dolomitos do Grupo Corumbá, sendo composta por um nível basal de calcretes, de tipo pedogenético e freático, sobreposto por um pacote de tufas micríticas (micrito inconsolidado), com grande quantidade de gastrópodes, distribuídos amplamente e aflorando em todas as planícies da região. Por fim temos os afloramentos de tufas calcárias do tipo fitohermal, compondo barragens e cachoeiras nas drenagens locais. Acredita-se que a deposição dos micritos ocorreu em ambiente lacustre, o que permitiu um depósito amplo e homogêneo, que posteriormente, em clima úmido, serviu de área fonte, juntamente com os carbonatos do Grupo Corumbá, para a geração das tufas fitohermais. A correlação estratigráfica dos depósitos de tufas calcárias estudados apontam para dois períodos de clima semi-árido a árido no Holoceno, que permitiram a formação e a alteração (calcretização) de depósitos, refletido na base da Formação Xaraiés, e o período climático recente, úmido, a formação das tufas fitohermais, no topo da formação. A ocorrência de lentes micríticas no sul do Pantanal pode significar que esta região também esteve exposta às dinâmicas climáticas vistas na Serra da Bodoquena. Estas constatações demonstram a alta variação climática da região, representada por depósitos que são pequenos e frágeis, mas dotados de significados genéticos indubitáveis. / Crop out abundantly in the Bodoquena Ridge drainages, southwest of Mato Grosso do Sul (MS) state, deposits of calcareous tufa were described as the top portion of Xaraiés Formation, representing the most notable deposit of this type in Brazil, due to the variety of forms. As the greatest attractiveness of Bonito, MS, an eco-tourism center, the calcareous tufa were presented in form of dams, waterfalls and deposits of micritic sediments, which generate natural pools and waterfalls so looked by tourists. Even with such importance, this region had not received a deep study, with sedimentology, stratigraphy and geomorphology approach. An accurate bibliographic review was done, and with field work and laboratory analyzes this work could obtain a panorama of the Xaraiés Formation in Bodoquena Ridge. In this region, can be noted that Xaraiés Formation goes directly over the limestone and dolomite of the Corumbá Group, and were composed by a basal layer of pedogenetic/groundwater calcrete, superimposed by a package of micritic sediments (micritic tufa), with a large amount of gastropods, which were widely distributed, cropping out in all plains of the region. Finally, we have the occurrences of calcareous tufa, fitohermal type, drawing dams and waterfalls in the regional drainages. It has believed that the deposition of lacustrine micritic sediments have occurred in an environment which were enabled a broad and homogeneous deposits. Subsequently, in a moister climate these sediments served as a source area, together with the limestone of the Corumbá Group, for the generation of fitohermal tufa. The stratigraphic correlation of the studied calcareous tufa deposits point to two periods of semi-arid/arid climate in Holocene, which allowed the calcretization. Those were reflected on the bottom of the Xaraiés Formation, and a recent wet climatic period, represented by the fitohermal tufa at the top of the formation. The occurrence of micritic lens in the southern Pantanal may mean that this region has also been exposed to the weather dynamics viewed in the Bodoquena Ridge. These findings show the high variation of climate in this region, represented by deposits, which are small and fragile, but gifted with unquestionable genetic meanings.
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Geotechnical Characterization And Rock Mass Classification Of The Antalya Karstic Rock MassesSopaci, Evrim 01 October 2012 (has links) (PDF)
This thesis identifies the geotechnical parameters of the Antalya karstic foundation rocks
(travertine/tufa), which are highly variable in nature, by means of geological observations,
geotechnical site investigations, and field and laboratory geomechanics tests to examine
karstic (mainly tufa) rock mass behavior. Several geotechnical parameters such as
porosity, seismic wave velocity, uniaxial compressive strength, Young&rsquo / s modulus, tensile
strength, etc. that are thought to have significant influence on rock mass behavior have
been tested and statistically analyzed. Principal component analysis and multiple linear
and non-linear regression analyses have been carried out in order to reveal correlations
between the geotechnical parameters tested. Porosity has been statistically determined to
be one of the major parameters governing the strength of the Antalya tufa rock mass.
Intact rock failure criteria, among which Bieniawski&rsquo / s criterion has been proven to be
more appropriate for each tufa type (phytoherm framestone, phytoherm boundstone,
microcrystalline tufa, phytoclast tufa and intraclast tufa) along with the Antalya tufa rock
mass have been determined from the experiments. GSI rock mass classification of the
Antalya tufa rock mass, whose GSI value was recommended between 20± / 5 and 75± / 5, has
been attempted to be used in engineering design. Furthermore, the depth and dimension of
the karstic cavities and fractures have been investigated by the geophysical tests, surface
geological survey and subsurface investigations (borings and observation pits).
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Tufas calcárias da Serra da Bodoquena, MS / \"Calcareous tufa from Bodoquena\'s Ridge, MS\"Emiliano Castro de Oliveira 13 April 2009 (has links)
Aflorando abundantemente nas drenagens da Serra da Bodoquena, região sudoeste do Estado de Mato Grosso do Sul, os depósitos de tufas calcárias, descritos como a porção superior da Formação Xaraiés, representam o mais notável depósito do tipo no Brasil, devido à variedade de formas. Sendo a maior atração do pólo eco-turístico de Bonito, MS, as tufas calcárias apresentam-se sob formas de barragens, cachoeiras e depósitos de micritos inconsolidados, que por sua vez geram as piscinas naturais e quedas dágua tão procuradas pelos turistas. Mesmo com tamanha importância, tal rocha não havia recebido um estudo aprofundando, que contemplasse sedimentologia, estratigrafia e geomorfologia. Através de criteriosa revisão bibliográfica, trabalhos em campo e análises laboratoriais, pôde-se obter um panorama da Formação Xaraiés na Serra da Bodoquena. Nesta região, observa-se que a formação, assentada diretamente sobre os calcários e dolomitos do Grupo Corumbá, sendo composta por um nível basal de calcretes, de tipo pedogenético e freático, sobreposto por um pacote de tufas micríticas (micrito inconsolidado), com grande quantidade de gastrópodes, distribuídos amplamente e aflorando em todas as planícies da região. Por fim temos os afloramentos de tufas calcárias do tipo fitohermal, compondo barragens e cachoeiras nas drenagens locais. Acredita-se que a deposição dos micritos ocorreu em ambiente lacustre, o que permitiu um depósito amplo e homogêneo, que posteriormente, em clima úmido, serviu de área fonte, juntamente com os carbonatos do Grupo Corumbá, para a geração das tufas fitohermais. A correlação estratigráfica dos depósitos de tufas calcárias estudados apontam para dois períodos de clima semi-árido a árido no Holoceno, que permitiram a formação e a alteração (calcretização) de depósitos, refletido na base da Formação Xaraiés, e o período climático recente, úmido, a formação das tufas fitohermais, no topo da formação. A ocorrência de lentes micríticas no sul do Pantanal pode significar que esta região também esteve exposta às dinâmicas climáticas vistas na Serra da Bodoquena. Estas constatações demonstram a alta variação climática da região, representada por depósitos que são pequenos e frágeis, mas dotados de significados genéticos indubitáveis. / Crop out abundantly in the Bodoquena Ridge drainages, southwest of Mato Grosso do Sul (MS) state, deposits of calcareous tufa were described as the top portion of Xaraiés Formation, representing the most notable deposit of this type in Brazil, due to the variety of forms. As the greatest attractiveness of Bonito, MS, an eco-tourism center, the calcareous tufa were presented in form of dams, waterfalls and deposits of micritic sediments, which generate natural pools and waterfalls so looked by tourists. Even with such importance, this region had not received a deep study, with sedimentology, stratigraphy and geomorphology approach. An accurate bibliographic review was done, and with field work and laboratory analyzes this work could obtain a panorama of the Xaraiés Formation in Bodoquena Ridge. In this region, can be noted that Xaraiés Formation goes directly over the limestone and dolomite of the Corumbá Group, and were composed by a basal layer of pedogenetic/groundwater calcrete, superimposed by a package of micritic sediments (micritic tufa), with a large amount of gastropods, which were widely distributed, cropping out in all plains of the region. Finally, we have the occurrences of calcareous tufa, fitohermal type, drawing dams and waterfalls in the regional drainages. It has believed that the deposition of lacustrine micritic sediments have occurred in an environment which were enabled a broad and homogeneous deposits. Subsequently, in a moister climate these sediments served as a source area, together with the limestone of the Corumbá Group, for the generation of fitohermal tufa. The stratigraphic correlation of the studied calcareous tufa deposits point to two periods of semi-arid/arid climate in Holocene, which allowed the calcretization. Those were reflected on the bottom of the Xaraiés Formation, and a recent wet climatic period, represented by the fitohermal tufa at the top of the formation. The occurrence of micritic lens in the southern Pantanal may mean that this region has also been exposed to the weather dynamics viewed in the Bodoquena Ridge. These findings show the high variation of climate in this region, represented by deposits, which are small and fragile, but gifted with unquestionable genetic meanings.
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Characterization of Ulva (Ulvaceae, Chlorophyta) species cultured in commercial abalone farms in South Africa, and comparison with closely related wild species, using morpho-anatomical and molecular methodsBachoo, Teejaswani 31 January 2022 (has links)
Seaweeds are among the five marine sub-sectors of species cultured in South Africa, with Ulva species cultured at a commercial scale. In South Africa, the annual production of Ulva is approximately 2000 tonnes (wet weight), with the majority of Ulva being grown in landbased paddle raceway systems receiving abalone effluent water. Cultured Ulva is mainly used as abalone feed and for bioremediation of farm effluent water. It is not sold but rather is used either as fresh feed or dried and incorporated into formulated feeds. The main commercial abalone farms growing Ulva in paddle raceway systems in South Africa are Irvin & Johnson (I&J) Cape Abalone, Abagold, Buffeljags Abalone and Diamond Coast Aquaculture in the Western Cape province, and Wild Coast Abalone in the Eastern Cape province. The main aim of this study is to precisely identify the cultured Ulva species as their identity is not clearly understood. This will provide information on the genetic diversity in the cultured material and could enable farmers to select for a species/strain that has the desired traits such as high nutritional value, rapid growth rate, resistance to diseases, and the ability to grow vegetatively, amongst others, so that the best feed is given to abalone. Next, the cultured Ulva species will be compared with closely related seashore Ulva species and with Ulva specimens from the main farming area in Hermanus to see if they are genetically similar. Ulva specimens from these farms, nearby seashores, including the Hermanus abalone farming complex in the New Harbour were identified using morpho-anatomical and molecular methods. The molecular markers employed in this study were the plastid large subunit of Ribulose-1,5-bisphosphate carboxylase/oxygenase (rbcL), Internal Transcribed Spacer of nuclear ribosomal DNA (ITS nrDNA) and the elongation factor tufA. The 12 cultured Ulva specimens belonged in the U. lacinulata clade with weak support value of 0.57 for PP in the rbcL tree, high support value of 0.86 for PP in the ITS tree and high support value of 92% and 0.92 for BP and PP, respectively, in the tufA tree. The seashore U. capensis and farmed Ulva specimens belonged in the same large U. lacinulata clade in the rbcL tree. However, the U. capensis samples and the locally cultivated Ulva samples belonged in separate sister clades with a support value of 70% and 0.75 for BP and PP, respectively, in the ITS phylogenetic tree, and 97% and 1 for BP and PP, respectively, in the tufA phylogenetic tree. Therefore, the identity of the cultivated Ulva samples is U. lacinulata and the clade containing the U. capensis samples has now been labelled as U. uncialis as it is an older available name than U. capensis. Furthermore, the foliose U. lacinulata was also found growing attached near the inlets of the Hermanus abalone farming complex in New Harbour. There was no genetic variation within the farmed Ulva samples as they were collapsed as a single haplotype by the three molecular markers. The genetic distance between the U. uncialis and farmed U. lacinulata samples were 0.16%, 0.76% and 0.92% for the markers, rbcL, ITS and tufA, respectively. Even though the low sequence divergence between the farmed U. lacinulata and U. uncialis specimens fits within the range of variability, these two clades are separate species that are closely related. Incongruences between the molecular and morpho-anatomical identification methods were observed, as the morpho-anatomical identification method identified 9 of the 12 farmed Ulva specimens as U. lactuca and the remaining as U. rigida sensu Stegenga et al. (1997). Fewer Ulva species were resolved morphologically because of the overlap in morphological description within U. lactuca sensu Stegenga et al. (1997) and U. rigida sensu Stegenga et al. (1997). Additionally, three new records of Ulva species (U. ohnoi, U. australis and U. stenophylloides) for South African seashore specimens were molecularly identified in this study, and foliose U. compressa was recorded for the first time in the region. In this study, the molecular marker tufA, was the best marker to delimit species, as its internal clades were better supported compared to the other two markers and it was able to better separate the farmed U. lacinulata samples and the seashore U. uncialis samples into two different clades.
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