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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.
141

\"Utilização do método dos povoamentos na caracterização de comunidades bentônicas em trecho do infralitoral consolidado da Enseada das Palmas, Ilha Anchieta, Ubatuba (SP)\" / Settlements method for the characterization of hard bottom benthic communities in an infralittoral stretch in Palmas Bay, Anchieta Island, Ubatuba (SP)

Natalia Pirani Ghilardi 27 March 2007 (has links)
A caracterização da biodiversidade de comunidades bentônicas resume-se, no litoral brasileiro, a pouco mais de uma dezena de trabalhos estudando, na totalidade, uma área aproximada de apenas 3400 m2. Pretendeu-se aqui propor um novo método, inédito para comunidades marinhas de substrato consolidado, baseado na amostragem de unidades de heterogeneidade da paisagem, denominados povoamentos, visando um aumento na velocidade e abrangência das amostragens neste ambiente. Este estudo foi realizado em um trecho de 260m do costão leste da Praia do Presídio (Enseada das Palmas, P. Est. de Ilha Anchieta, Ubatuba, SP) e divididiu-se em quatro abordagens: 1) identificação e descrição dos povoamentos presentes e spécies neles dominantes; 2) mapeamento da repartição horizontal geo-referenciada de cada povoamento e determinação de sua amplitude vertical máxima; 3) quantificação de seus recobrimentos percentuais médios a partir de imagens; 4) avaliação da composição específica e da variação espacial de povoamentos selecionados. Trinta povoamentos, incluídos nas categorias Banco, Colônia, Crosta e Tapete, além de um atributo não-biológico incluído na categoria Região, foram identificados e descritos e as informações serão disponibilizadas em um banco de dados na internet. O mapeamento foi realizado em apenas 6 mergulhos, em cada estação, de 50 a 80 minutos. A maior parte os povoamentos ocorreu pontualmente. O número de povoamentos e a repartição horizontal dos mesmos praticamente não se alteraram entre verão e inverno. A análise da freqüência relativa dos povoamentos evidenciou que Banco de Sargassum (BSG) apresentou maior valor no verão (25,3%) e Tapete de Amphiroa e Jania (TAJ), no inverno (21,3%). Quanto à distribuição vertical, foram delimitadas quatro principais zonas baseadas na freqüência relativa: uma mais rasa definida por BSG, outra intermediária superior definida por TAJ, outra intermediária inferior definida por Tapete de Ectoprocta (TEC) e uma mais funda definida por povoamentos variáveis com a estação. Foram obtidos 84 elementos amostrais fotográficos no verão e 100 no inverno, os quais evidenciaram 26 e 28 povoamentos, respectivamente. Foram realizadas análises de repartição espacial nos modos R e Q e avaliação de heterogeneidade dos agrupamentos formados. BSG apresentou maior valor de recobrimento percentual médio tanto no período de verão (26,1%) quanto de inverno (32,0%), seguido de TEC (19,7% no verão e 24,2% no inverno), significativamente maior que a maioria dos demais povoamentos (p<0,05). Os povoamentos fitobentônicos foram mais representativos na área (62,2% de recobrimento médio no verão e 61,8% no inverno). Quando consideradas as categorias de povoamentos, os bancos fitobentônicos foram mais representativos (31,2% no verão e 37,0% no inverno). Se somados animais e algas, a categoria ?tapete? foi a mais representada (46,3% no verão e 41,4% no inverno), com grande contribuição dos povoamentos TAJ e TEC, indicando uma possível influência da sedimentação na área. A análise de repartição espacial em Modo R evidenciou a existência de seis grupos no verão e cinco no inverno, sugerindo povoamentos com as mesmas exigências ecológicas. Já em Modo Q observou-se que a comunidade da área é bastante heterogênea, apresentando um padrão em manchas, sendo os povoamentos BSG, Região de Substrato Inconsolidado, TAJ, TEC (e algumas de suas variações) e Tapete de Gelidiopsis e Hypnea (TGH) os responsáveis pela formação dos grupos com o Índice de Similaridade de Morisita-Horn. A análise da composição específica dos povoamentos BSG, TAJ, TEC e TGH evidenciou que os mesmos podem ser considerados homogêneos ou apresentam-se na forma de fácies na área de estudo, podendo ser utilizados como unidades operacionais de forma consistente. Entretanto, estudos em outras áreas são necessários para fornecer suporte aos dados obtidos, principalmente em relação aos dois últimos povoamentos, que carecem de estudos ecológicos. A análise espectral evidenciou suficiência amostral para todos os povoamentos em relação aos pontos Calleja adotados. Os espectros de riqueza foram diagonais e os de diversidade foram retangulares. Para os quatro povoamentos, o Índice de Diversidade de Shannon ficou entre 1,6 e 2,2 e o de Diversidade de Simpson, entre 2,6 e 5,7. O povoamento TGH foi o mais rico e o mais diverso. A comunidade estudada no presente estudo pode ser considerada característica da região sudeste do Brasil. O método dos povoamentos, tanto a partir da Abordagem 2 quanto da 3, possibilitou a caracterização estrutural da comunidade de forma rápida. A análise da micro-heterogeneidade de 4 povoamentos evidenciou que podem ser utilizados como unidades ecológicas consistentes. / The biodiversity characterization of benthic communities in the Brazilian coast is limited to a few works, which studied an area of about 3,400 m2. The objective of this study was to propose a new method, unprecedented in hard bottom marine communities, based in the sampling of landscape heterogeneity units, named physiognomies and settlements, aiming at an increase in sampling speed and covering in this environment. This study was performed in a 260 m infralittoral stretch of Presidio Beach eastern coast (Palmas Bay, Anchieta Island State Park, Ubatuba, SP) and was divided in four approaches: 1) identification e description of settlements and their dominant species; 2) georeferenced spatial repartition mapping of each settlement and determination of maximum vertical amplitude; 3) mean percent cover quantification from digital images; 4) evaluation of specific composition and spatial variation of selected settlements. Thirty settlements, included in Bed, Colony, Crust and Turf categories, besides a non-biological attribute included in Region category, were identified and described and the information will be available in a database in the internet. Mapping was performed in only 6 dives of 50 to 80 minutes in each season. The major part of the settlements occurred punctually. Settlements number and horizontal repartition practically did not change between summer and winter. Sargassum Bed (SGB) was more frequent in the summer (25.3%) and Amphiroa and Jania Turf (AJT) in the winter (21.3%). In relation to vertical repartition, four main zones were delimited based in relative frequencies: a shallower one defined by SGB, another upper intermediary defined by AJT, another lower intermediary defined by Ectoprocta Turf (ECT) and a last one, deeper, defined by variable settlements according to season. Eighty four sampling units were obtained in summer and 100 in winter, from which 26 and 28 settlements could be recognized, respectively. Cluster analysis in R and Q modes and heterogeneity evaluation of the obtained groups were made. SGB showed the highest mean percent cover as much in summer (26.1%) as in winter (32.0%), followed by ECT (19.7% in summer and 24.2% in winter), significantly higher than most of the other settlements (p<0.05). Phytobenthic settlements were the most representative in the area (62.2% of mean cover in summer and 61.8% in winter). When settlements categories were considered, phytobenthic beds were the most representative (31.2% in summer and 37.0% in winter). With animals and algae altogether, the category ?turf? was the most represented (46.3% in summer and 41.4% in winter), with great contribution of AJT and ECT, indicating a possible sedimentation influence in the area. The cluster analysis in R Mode showed the existence of six groups in summer and five in winter, suggesting settlements with the same ecological exigencies. In Q Mode a highly heterogeneous community could be evidenced, showing a patchy pattern. The settlements SGB, Unconsolidated Substrate Region, AJT, ECT (and some of its variations) and Gelidiopsis and Hypnea Turf (GHT) were the responsible for group formation with the use of Morisita-Horn Similarity Index. Specific composition analysis of SGB, AJT, ECT and GHT showed that these settlements can be considered homogeneous or present themselves as facies in the study area and can be consistently used as operational units. However, studies in other areas are necessary in order to give support to the obtained data, mainly regarding ECT and GHT, which lack ecological studies. Spectral analysis made evident sampling sufficiency for all settlements in relation to Calleja points adopted. Richness spectra were diagonal and diversity spectra were rectangular. For the four settlements, Shannon?s Diversity Index was between 1.6 and 2.2 and Simpson?s Dominance Index, between 2.6 and 5.7. GHT was the richest and most diverse settlement. The community studied in the present work can be considered typical of Brazilian south eastern region. Settlements method, through approaches 2 and 3, facilitated community structural characterization in a fast way. Micro-heterogeneity evaluation of four settlements showed that they can be used as consistent ecological units.
142

Macrofauna associada à comunidade Bostrychietum em diferentes ambientes no litoral norte de São Paulo / Macrofauna associated with Bostrychietum community in different environments on the northern coast of São Paulo

Garcia, Abel Furlan, 1984- 23 August 2018 (has links)
Orientador: Fosca Pedini Pereira Leite / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-23T22:36:54Z (GMT). No. of bitstreams: 1 Garcia_AbelFurlan_M.pdf: 2175839 bytes, checksum: 3883ef33f2fc268ad9117685b3795634 (MD5) Previous issue date: 2013 / Resumo: As algas do gênero Bostrychia, juntamente com outras algas, formam uma comunidade que está presente nos costões, bem como associadas com pneumatóforos nos manguezais. Sua estrutura complexa propicia a retenção de sedimento, água e matéria orgânica, bem como um mosaico de algas que varia temporalmente e, formando microhabitats que são refúgios para a fauna. O objetivo deste estudo é analisar a distribuição da fauna associada à comunidade de algas Bostrychietum e os fatores que influenciam a sua distribuição. Foram amostrados dois costões rochosos e uma área de manguezal no litoral norte do Estado de São Paulo. Nestes locais, foram realizadas quatro coletas durante o ano de 2012, sendo obtidas amostras para a identificação da fauna associada e para a análise de fatores ambientais (teor de matéria orgânica e granulometria do sedimento). O peso da amostra (peso seco da alga + do sedimento) foi usado para o cálculo da densidade de indivíduos. A composição das algas variou nos meses amostrados em todos os locais. Amostras do mesolitoral apresentaram mais espécies de algas associadas que as do supralitoral. Tal fato influenciou a distribuição da macrofauna, uma vez que a diversidade diminuiu nas amostras com menos espécies de algas. Os moluscos e anfípodes onívoros foram abundantes em todas as amostras, sendo os anfípodes Hyalidae dominantes. A interação entre as variações sazonais das algas da comunidade e o hidrodinamismo modula a distribuição da macrofauna nos costões. No manguezal, os pneumatóforos mais próximos da água apresentaram diferenças com relação às amostras do interior do mangue quanto à composição de algas e da fauna associada. O Bostrychietum é, portanto um microecossistema com vários fatores modulando as interações entre as espécies, sendo necessárias maiores investigações das relações existentes entre as espécies e os fatores ambientais atuantes / Abstract: The algae of the genus Bostrychia together with other algae form a community present in rocky shores as well as associated to pneumatophoresin mangroves. Both their complex structure with ramifications which provide sediment, water and organic matter retention and the algae mosaic that varies seasonally foster microhabitats which are refuges for the fauna during low tide periods. The aim of this study was to evaluate the distribution of fauna associated wih algal community Bostrychietum and the factors that influence their distribution.Two rocky shores and one mangrove area in the Northern shore of São Paulo State were sampled. In these sites four samplings were made during the year of 2012: samples were collected for the identification of the associated fauna and for the analysis of environmental factors (organic matter content and sediment grain size). The weight of the sample (alga dry weight + sediment dry weight) was used to calculate the density of individuals. The algal composition varied through the sampled months as well as in relation to distance from the sea. Samples located in the mesolittotal presented more algal species associated. Such fact influenced macrofauna distribution since diversity was lower for samples containing less algal species. Omnivore mollusks and amphipods were abundant in all samples, Hyalidae amphipods being dominant.The interaction between seasonal variations of the algae in the community and the hydrodynamics modulates the distribution of macrofauna on the rocky shores. In the mangroves, those pneumatophores closer to the water presented diferences in relation to the composition of algae and associated fauna compared to samples from inner parts of the mangrove. Thus, Bostrychietum is a microecosystem with many factors modulating the interactions between species, making further investigation on the existing relationships between species and the operating environmental factors necessary / Mestrado / Ecologia / Mestre em Ecologia
143

Desenvolvimento e análise de desempenho de um quebra-mar construído a partir de garrafas de politereftalato de etileno (pet) / Develpoment and performance analysis of polyethylene terephthalate (pet) bottle floating break-water

Vieira, Luana Kann Kelch, 1985- 20 August 2018 (has links)
Orientador: Tiago Zenker Gireli / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-20T11:55:27Z (GMT). No. of bitstreams: 1 Vieira_LuanaKannKelch_M.pdf: 9568135 bytes, checksum: e1cf844235f741c2950c6e1ecba0b1ed (MD5) Previous issue date: 2012 / Resumo: O desenvolvimento econômico brasileiro tem gerado a necessidade de melhoria no transporte e logística dos produtos que circulam pelo país. O transporte marítimo é a opção menos poluente e menos custosa para o transporte de mercadorias. Com o aumento da demanda neste segmento surge o interesse por alternativas ecológicas e economicamente mais atrativas. Como parte integrante do projeto de um terminal portuário, obras de abrigo são necessárias na grande maioria dos casos. Nesse contexto, foi resgatada a importância da pesquisa e inovação do quebra-mar flutuante. Além disso, o quebra-mar também pode promover proteção costeira, outra discussão muito atual. O quebra-mar desenvolvido e estudado nesse trabalho é uma inovação e possui vantagens dentre as concepções praticadas atualmente. O conceito ecológico de empregar garrafas PET descartadas, eliminando-as do ambiente, cria um interesse ímpar por parte dos ambientalistas. Economicamente esse quebra-mar é mais vantajoso, pois os materiais são de baixo custo e de fácil aquisição. E também pode ser construído em terra e rebocado para a posição, no corpo d'água, eliminando as dificuldades e custos de uma construção a partir de plataformas destacadas e flutuantes. Por último, ressalta-se a eficiência na redução da altura de onda, pois esta foi significativamente maior que a encontrada por pesquisadores que testaram concepções comparáveis a essa / Abstract: The growth of the Brazilian economy urges for improvement in transportation and logistics for products that move though the country. Seaways are the less pollutant and the most cost effective way to move ware. The increasing demand for this segment creates interest in more environmentally friendly and cheaper options and sheltering installations are part of a port's design. Within this scenario, the relevance of research and innovation for floating breakwater is recovered. Furthermore breakwater can as well provide coastal protection, which is an existent concern in modern time. The floating breakwater that is being discussed in this paper is an innovative and advantageous when compared to others that are in use have been designed and built. Due to the reuse of many plastic bottles and regarding the fact that they are being taken away from the waste environment, this floating breakwater creates a good impact on the ecologists. From the economic point of view it is less expensive due to the fact of the purchase of used plastic bottles to be cheap and easy. Also, the breakwater can be constructed on shore and dragged to position which eliminates the complexity and coast of building of a vessel. Its efficiency in wave height reduction goes significantly beyond the reduction ratio of other concepts that are comparable to this floating breakwater / Mestrado / Recursos Hidricos, Energeticos e Ambientais / Mestre em Engenharia Civil
144

Paleoenvironment and shore displacement since 3200 BC in the central part of the  Långhundraleden Trail, SE Uppland

Katrantsiotis, Christos January 2013 (has links)
In this study, litho-, bio- and chronostratigraphic investigations combined with RTK GPSleveling have been carried out to reconstruct the paleoenvironment in the central part of theLånghundraleden Trail. The area displays four shallow lake basins of varyingmorphologies. The basins are now covered with peat as a result of infilling and overgrowth.The emergence of the saddle-point, i.e. the highest point of the underlying minerogenicsurface, was estimated to have occurred c. BC/AD. The isolation events of two basins, atc.12.4 and c.12.3 m a.s.l. west and east of the saddle-point, were dated to c.AD 20 andc.AD 30, respectively. By combining these isolation data with six previously investigatedbasins a shore displacement curve for the central part of the Långhundraleden Trail and thesurrounding area, i.e. east of the Ekoln basin was constructed. The curve indicates anaverage regressive shore displacement rate of c.6.2 mm/yr since c. 3200 BC. Around 1500BC, this trend was interrupted by a short period of retarded regression, correlated with theL4 event. The isolation ages of the basins in the Långhundraleden Trail appears relativelyyoung when compared to an average shore displacement rate of 5.6 mm/year in thenorthern part of L. Mälaren, west of the Ekoln basin. As the area is dominated by a fissurevalleylandscape, this discrepancy could be attributed to small-scale irregular tectonicmovements, which caused faster uplift rate, i.e. 6.2 mm/year, east of the Ekoln basin.
145

Morphodynamics of Egmont Key at the Mouth of Tampa Bay: West-Central Florida

Tyler, Zachary James 13 April 2016 (has links)
Egmont Key, located at the mouth of Tampa Bay, is part of a dynamic system with many interrelated natural and anthropogenic factors influencing its morphodynamics. This study started in August 2012. During the 3-year period until August 2015, 28 beach profile transects were established and surveyed 10 times. Seventeen historical aerial images from 1942 to 2013 were geo-rectified and analyzed. Three hundred and fourteen sediment samples were procured from the navigation channel dredge area and the beach nourishment area and analyzed for grain size. A numerical wave model was established to simulate the nearshore wave field. The overall goals of this study are to understand the complex morphodynamics of Egmont Key and to evaluate the shore-protection efforts. The overall area of the Egmont Key has reduced 52% from 2.1 km2 in 1942 to 1.o km2 in 2002. The area loss was mostly caused by beach erosion along the Gulf-facing beach. The island-area reduction from 1942 to 2002 was largely linear. Two periods of accelerated area loss from 1978-1984 and 1999-2002 can be related to dredging of the Egmont Channel and the disposal of dredged materials along the channel. Concerning the relatively high mud content in the borrow area for the 2014 nourishment, a large amount of the fine sediment was lost at a temporal scale of hours to days during the dredging and beach nourishment construction processes. Some of the mud was deposited outside the surf zone at water depths of 2 m or greater. This mud became eroded naturally by energetic conditions at a temporal scale of months. Beach erosion and accretion along the Gulf-facing beach can be related qualitatively to tidal flow patterns. Numerical wave modeling shows that the transverse bars offshore Egmont Key have a moderate influence on the wave field, leading to slightly different wave heights along the shoreline. However, there is no clear relationship between the nearshore wave conditions and the erosion/accretion patterns. The severe shoreline erosion has exposed various fort structures at the shoreline and in the nearshore zone. These structures function as detached breakwaters or groins and have localized influence on the beach state.
146

A hybrid approach to beach erosion mitigation and amenity enhancement, St Francis Bay, South Africa

Anderson, Dylan Rory January 2008 (has links)
The St Francis Bay beach has experienced chronic erosion over the past three decades. This erosion can largely be attributed to the stabilisation of a large coastal dunefield which contributed +/- 80 percent of the sand supply to St Francis Bay. Stabilisation began in 1975 initially using plant cuttings and followed by the development of the Santareme holiday suburb resulting in complete stabilisation by 1985. Effects were felt from the late 1970‟s and since then the beach has retreated at between 0.5 - 3 m.yr-1. Erosion has encroached on beachfront properties since the early 1990‟s, leading to the placement of 3-4 m high unsightly rock revetments along much of the beach. Where properly maintained these structures have proved successful in protecting the properties behind, however exacerbated erosion of areas in front and adjacent to these structures is evident. Currently no dry beach is present at high tide for most of the year, leading to a significant reduction in beach amenity value. Several technical studies to investigate remediation of this beach erosion problem have been conducted since the early 1990‟s. This study includes investigations into the processes and dynamics of the existing environment and evaluation of the effectiveness and impacts of several elements of a hybrid approach to coastal protection and amenity enhancement for St Francis Bay beach. This proposal incorporated: Multi-Purpose Reefs (MPR‟s) offshore, for coastal protection and amenity enhancement in terms of surfing; beach nourishment with sand from the Kromme Estuary and dune rehabilitation with appropriate native sand binding species. Extensive fieldwork and data collection were conducted, this included: a series of bathymetric surveys; diving surveys and a helicopter flight; sediment sampling; beach profiling and deployment of a wave/current meter. Analysis of these data provided a greater understanding of the existing environment and dynamics of St Francis Bay and provided reliable inputs for numerical modelling. Numerical and physical modelling was conducted to assess the existing processes and conduct MPR design testing. In addition calibrated hydrodynamic modelling of the Kromme Estuary was conducted in order to assess the impacts of sand extraction from the large sand banks within the mouth of the Kromme Estuary for use as beach nourishment. Comparison of bathymetric survey data collected by the author in 2005/06 with survey data collected by the South African Navy Hydrographic Office (SANHO) in 1952 suggest a major loss of sand from the bay, with a volume difference of some 8.8 X 106 m3 calculated. Greater losses were measured between 10-15 m water depths, with shallow areas of +/- 5 m water depth, remaining more stable. This can be attributed to the presence of shallow reef and rocky substrate through much of the bay at this depth range. Monthly RTK GPS survey data from September 2006 to September 2007 indicates a total loss of 40 000 m3 over this period with the greatest losses measured along the northern part of the beach. The greatest losses were measured after large long period waves from a southerly to south-easterly direction occurred in conjunction with equinox tides in mid March 2007. Sediment sampling at over 100 locations within the bay indicated a high percentage of reef (26 percent) and fairly consistent grain size in the fine to medium size class throughout much of the beach, bay and large sand bank within the estuary. While the majority of the South African Coast is exposed to the predominant south westerly winds and waves, St Francis Bay‟s orientation means that waves from a south easterly to easterly direction dominate. The results of the detailed numerical modelling of the hydrodynamics agree with previous calculations and modelling results which concluded that strong unidirectional longshore currents occur along the headland due to the oblique angle of wave incidence and the close to parallel angle of wave incidence along the beach leads to weak longshore currents of variable direction. Erosion along St Francis Bay beach is a result of cross-shore erosion due to large waves from a southerly to easterly direction. Detached breakwaters are the most effective form of coastal protection in these environments and MPR‟s offer additional benefits over traditional breakwater structures. Results of empirical calculations and numerical modelling indicate that the MPR‟s will provide effective coastal protection through the processes of wave dissipation, wave rotation, salient formation and alteration of nearshore circulation. Physical modelling results allowed the MPR design to be assessed and refined in terms of surfing amenity enhancement and construction constraints. In addition numerical modelling results indicate that impacts due to the extraction of up to 600 000 m3 of sand from the lower Kromme Estuary result in highly localised velocity reduction, mainly limited to the extraction areas. The calculated rate of sediment influx into the lower Kromme Estuary indicates that limited extraction, in the order of 20 000 – 40 000 m3 per year, should be sustainable in the long term. Sedimentation of the lower estuary over recent years has had negative recreational and ecological impacts, through reduced navigability and water exchange respectively. Therefore both the estuary and beach systems prove to benefit from this approach. Although not investigated in detail as part of this study, evidence from numerous projects worldwide indicates that foredunes help to trap wind-blown sand on the beach and form a buffer to storm erosion, therefore dune rehabilitation with native sand-binding plant species was recommended as the third element of the proposed remediation of St Francis Bay beach.
147

Systematics and phylogeography of the genus Tigriopus (Copepoda, Harpacticoida, Harpacticidae) in the basin of the Mediterranean Sea

Vecchioni, Luca 23 March 2021 (has links)
[ES] El género de copépodos Tigriopus Norman, 1869 se distribuye en todo el mundo en piscinas costeras de rocas y actualmente se considera que incluye 15 especies válidas. Tigriopus fulvus (Fischer, 1860), con su subespecie Tigriopus fulvus adriaticus Van Douwe 1913 y Tigriopus fulvus algiricus Monard 1935, actualmente se informa que ocurren en el área mediterránea, pero actualmente se desconoce la diversidad real del género. Nuestro objetivo fue evaluar la identidad real de las poblaciones mediterráneas de Tigriopus y dilucidar su taxonomía y patrón de diversidad genética. Para alcanzar estos objetivos, utilizamos dos enfoques diferentes. El primero, basado en la morfología, donde las posibles diferencias morfológicas entre muestras topotípicas de Tigriopus fulvus s.s. y muestras topotípicas de las dos subespecies fueron investigadas. Un segundo, sobre una base molecular, donde se secuenciaron fragmentos de dos genes de ADN mitocondrial (subunidad I de citocromo c oxidasa, COI y subunidad de ARN ribosómico pequeño, 12S) y un gen de ADN nuclear (28S) para ser usados como marcador de referencia. En este marco, se utilizaron enfoques taxonómicos moleculares, como el descubrimiento automático de brechas de código de barras (ABGD), bPTP (procesos de árbol de Poisson bayesianos) y la relación K / ¿, para investigar la existencia de las supuestas subespecies de Tigriopus a través de la identificación de Operacional Unidades Taxonómicas (OTU). Nuestros datos sugieren la presencia de una sola especie caracterizada por una notable estructura genética basada en la geografía en toda el área de estudio. El patrón de diversidad observado se atribuye tentativamente aquí a una fuerte monopolización de los estanques de rocas por parte de los primeros inmigrantes que los alcanzan. Sin embargo, tal monopolización se ve interrumpida periódicamente por los eventos de extinción locales, que son frecuentes en los hábitats intrínsecamente inestables de las piscinas de rocas Aquí proponemos para este patrón el nombre de "monopolización periódica" ("Clockwork monopolization"). / [CA] El género de copépodos Tigriopus Norman, 1869 se distribuix en tot el mon en piscines costeres de roques i actualment se considera que inclou 15 especies valides. Tigriopus fulvus (Fischer, 1860), en la seua subespecie Tigriopus fulvus adriaticus Van Douwe 1913 i Tigriopus fulvus algiricus Monard 1935, actualment s'informa que ocorren en l'area mediterranea, pero actualment se desconeix la diversitat real del género. Nostre objectiu fon evaluar l'identitat real de les poblacions mediterranees de Tigriopus i dilucidar la seua taxonomia i patrón de diversitat genetica. Per a alcançar estos objectius, utilisem dos enfocaments diferents. El primer, basat en la morfologia, a on les possibles diferencies morfologiques entre mostres topotípicas de Tigriopus fulvus s.s. i mostres topotípicas dels dos subespecies foren investigades. Un segon, sobre una base molecular, a on se secuenciaron fragments de dos gens d'adn mitocondrial (subunidad i de citocromo c oxidasa, coi i subunidad d'arn ribosómico menut, 12s) i un gen d'adn nuclear (28s) per a ser amprats com marcador de referencia. En este marc, s'utilisaren enfocaments taxonomics moleculars, com el descobriment automatic de breches de codic de barres (ABGD), bPTP (processos d'arbre de poisson bayesianos) i la relacio K/¿, per a investigar l'existencia de les supostes subespecies de Tigriopus a través de l'identificacio d'operacional unitats taxonomiques (OTU). Nostres senyes sugerixen la presencia d'una sola especie caracterisada per una notable estructura genetica basada en la geografia en tota l'area d'estudi. El patrón de diversitat observat s'atribuix tentativament aci a una forta monopolisacio dels safarejos de roques per part dels primers immigrants que els alcancen. No obstant, tal monopolisacio se veu interrompuda periodicament pels events d'extincio locals, que son freqüents en els hábitats intrinsecament inestables de les piscines de roques aci proponem per a este patrón el nom de "Monopolisacio Periodica" ("Clockwork Monopolization"). / [EN] The copepod genus Tigriopus Norman, 1869 is distributed worldwide in coastal rock-pools and it is currently considered to include 15 valid species. Tigriopus fulvus (Fischer, 1860), with its subspecies Tigriopus fulvus adriaticus Van Douwe, 1913 and Tigriopus fulvus algiricus Monard, 1935, are currently reported to occur in the Mediterranean area, but the actual diversity of the genus is currently unknown. We aimed to assess the actual identity of Mediterranean Tigriopus populations and to elucidate their taxonomy and pattern of genetic diversity. In order to reach these goals, we use two different approaches. The first, based on morphology, where the possible morphological differences among topotypical samples of Tigriopus fulvus s.s. and topotypical samples of the two subspecies were investigated. A second, on a molecular basis, where fragments of two mitochondrial DNA genes (cytochrome c oxidase subunit I, COI and small ribosomal RNA subunit, 12S) and a nuclear DNA gene (28S) were sequenced to be used as a reference marker. In this frame, molecular taxonomical approaches, such as Automatic Barcode Gap Discovery (ABGD), bPTP (bayesian Poisson Tree Processes) and K/¿ ratio, were used in order to investigate the existences of the alleged subspecies of Tigriopus through the identification of Operational Taxonomic Units (OTUs). Our data suggest the presence of a single species characterized by a noteworthy geographically-based genetic structure in the whole study area. The observed diversity pattern is tentatively ascribed here to a strong monopolization of the rock pools by the first immigrants that reach them. However, such a monopolization is periodically disrupted by local extinction events, which are frequent in the intrinsically unstable rock pool habitats. We propose the name "clockwork monopolization" for this pattern. / Vecchioni, L. (2020). Systematics and phylogeography of the genus Tigriopus (Copepoda, Harpacticoida, Harpacticidae) in the basin of the Mediterranean Sea [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/144122 / TESIS
148

The Use of Community-Based Conservation in Natural Resource Management: Case Studies from The Nature Conservancy of Virginia

Babylon, Ruth G. 20 November 2003 (has links)
In March 2002, The Nature Conservancy purchased a 9,000-acre tract of land on and near Warm Springs Mountain in Bath County, Virginia. The purpose of this paper is to examine community-based conservation strategies utilized by The Nature Conservancy in two well-established Virginia reserves to determine the effectiveness of those strategies in the protection of Warm Springs Mountain. The Conservancy's previous work on Virginia's Eastern Shore and in the Clinch Valley of southwest Virginia reveals the organization's transition from a strategy of mere land acquisition to the use of community-based conservation in an effort to involve local citizens and promote a proper balance between economics and the environment. The community-based conservation model developed by TNC on the Eastern Shore and utilized further in the Clinch Valley works well for ecoregions that fit a particular typology. The paper discusses the differences between that typology and the factors affecting the protection of Warm Springs Mountain. In addition, the paper outlines the lessons TNC learned from both positive and negative experiences in the two earlier preserves and proposes how these lessons can be applied to the Warm Springs Mountain Preserve. / Master of Urban and Regional Planning
149

Měření tvrdosti plastů

Brunclík, Štěpán January 2019 (has links)
This diploma thesis deals with the hardness measurement of plastics. Thesis is divided into four main parts. The first part deals with an overview of existing research findings in the field of hardness measurement of plastics. This part of the work is devoted to the description of principles and procedures, used indenters, sizes of test loads and evaluation of individual test methods. The second part deals with the measurement of the hardness of the test specimens for the selected plastic materials and the comparison with the hardness values declared by the manufacturer. The third part is focused on the suitability of the used methods for measuring the hardness of selected materials. The last part deals with the possible differences in the measured and manufacturer declared values of hardness of plastic materials.
150

Eastern Shore Substance Abuse Resource Directory

Malkus, Amy J. 01 January 2003 (has links)
No description available.

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