417 resultados para Inhabit
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Aquatic plants of the genus Ruppia inhabit some of the most threatened habitats in the world, such as coastal lagoons and inland saline to brackish waters where their meadows play several key roles. The evolutionary history of this genus has been affected by the processes of hybridization, polyploidization, and vicariance, which have resulted in uncertainty regarding the number of species. In the present study, we apply microsatellite markers for the identification, genetic characterization, and detection of hybridization events among populations of putative Ruppia species found in the southern Iberian Peninsula, with the exception of a clearly distinct species, the diploid Ruppia maritima. Microsatellite markers group the populations into genetically distinct entities that are not coincident with geographical location and contain unique diagnostic alleles. These results support the interpretation of these entities as distinct species: designated here as (1) Ruppia drepanensis, (2) Ruppia cf. maritima, and (3) Ruppia cirrhosa. A fourth distinct genetic entity was identified as a putative hybrid between R. cf. maritima and R. cirrhosa because it contained a mixture of microsatellite alleles that are otherwise unique to these putative species. Hence, our analyses were able to discriminate among different genetic entities of Ruppia and, by adding multilocus nuclear markers, we confirm hybridization as an important process of speciation within the genus. In addition, careful taxonomic curation of the samples enabled us to determine the genotypic and genetic diversity and differentiation among populations of each putative Ruppia species. This will be important for identifying diversity hotspots and evaluating patterns of population genetic connectivity. © 2015 The Linnean Society of London, Biological Journal of the Linnean Society, 2015, 00, 000–000.
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Dissertação apresentada na Universidade de Lisboa - Faculdade de Arquitetura, para obtenção do Grau de Mestre em Arquitetura.
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Dissertação de Mestrado em Arquitetura, apresentada na Faculdade de Arquitetura da Universidade de Lisboa, para obtenção do grau de Mestre.
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Para la sociología es fundamental aproximarse, evidenciar y analizar permanentemente el surgimiento y desarrollo de nuevas dinámicas sociales y políticas con el propósito de elaborar diagnósticos y estudios sociológicos que consideren la complejidad de la realidad desde una perspectiva holística. La presente investigación surge precisamentedel interés por comprender la emergencia de nuevas organizaciones políticas en la ciudad de Cuenca. Este trabajo, en particular analizará, cómo la vivencia de la ciudad es una forma de construir tanto el imaginario del lugar que se habita y al que se pertenece, así como la identidad de los sujetos colectivos que interactúan en esa ciudad; en este caso, el sujeto de estudio es el movimiento anarquista, autodenominado Colectivo Libertario en el marco de la cultura política cuencana. Visibilizar nuevas dinámicas organizacionales y manifestaciones como ésta, significa reconocer nuevas propuestas políticas, culturales e ideológicas, así como revelar elementos de ladiversidad social y cultural que integran nuestra sociedad.Este estudio intenta aportar al entendimiento de nuevas expresiones políticasy profundizar el análisis del entorno ciudadano en el que emergen; por ello sus resultados serán socializados con el propio colectivo y con otros actores sociales de la ciudad.
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Sea urchins are benthic macroinvertebrates that inhabit shallow coastal waters in tropical and temperate zones. Urchins are usually classified as generalists or omnivores as they can adjust their diet according to the food resources available in the environment. Due to the strong grazing pressure they may exert, urchins have an important role in marine ecosystems, occupying different trophic levels and stimulating the intensification of the dynamics of communities where they occur. In 2004, a monitoring program focused on the population dynamics of the white sea urchin, Tripneustes ventricosus, has been initiated in the Fernando de Noronha Archipelago. At the same time, a surprisingly lack of information on the species biology has been noted, despite their wide geographical distribution and economic importance in many parts of its range. Hence, this work was developed to provide information on the feeding habits of T. ventricosus in the archipelago. Ten specimens were collected between December 2006 and July 2007 at two sites of the archipelago, Air France and Sueste Bay for biometrics and analysis of gut contents. Test diameters ranged from 9.19 cm (± 1.1) to 10.08 cm (± 0.58). Calculated stomach repletion index (IRE) was higher (p <0.05) in the Air France site and also during January and July. The IRE was not correlated to the gonad index. Fifteen different species of algae were detected in a total of 120 stomachs examined: 4 Chlorophytas, 4 Phaeophytas and 6 Rhodophytas. Food diversity (p <0.05) was higher in December 2006 and January 2007. Although several items had a high frequency of occurrence, they were low represented in terms of weight, and consequently, had a low level of relative importance. The brown algae Dictyopteris spp and Dictyota spp, followed by the green algae Caulerpa verticillata accounted for the greatest importance in T. ventricosus diet, comprising about 90% of the consumed items
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The present work was carried out at the Atol das Rocas (3º 51 S; 33º 49 W), the only atoll of the South Atlantic and the first Brazilian marine protected area. It was guided by the following hypothesis: the composition of the fish communities varies in agreement with the position of the pools; in other words, with or without permanent ocean connection. To test the validity of this hypothesis, the fish abundance was estimated in the connected pools (Barretinha/Barreta Falsa) and unconnected ones (Cemiteriozinho/Âncoras), carrying an ecological characterization of the fishes that inhabit these pools. Additionally, the structural complexity of the sampled places was also evaluated intending to verify the variations of the abundance and diversity of fishes in function to this factor. By the fact of this research was being carried out through the limits of a conservation unit, the samples was realized using visual census techniques. The results generated through uni and multivariate analytic techniques allowed the evidence that decisive factor in the density, richness and diversity variations of fishes are linked to the substratum type (Hard / Soft bottom) and not by the fact that the pool are or are not connected permanently to the ocean. In relation to the structural complexity; 58% of the variations in the diversity of fishes were attributed to changes in the structural complexity, while 12% of the variations in the abundance were attributed to the structural complexity
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Diamondback terrapins (Malaclemys terrapin) are native to the remote oceanic islands of Bermuda and presently inhabit only four small brackish water ponds on a private golf course. The life history of this species is poorly understood on Bermuda and so the aim of this study was to fill these knowledge gaps, to compare the results with what is known from other areas in the North American range, and to inform the development of a local management plan. The results of a mark-recapture census revealed that ca. 100 individuals ≥81 mm straight carapace length live on Bermuda, of which nearly half (48.5%) were considered sexually mature. The population is dominated by females (sex ratio 2.9:1) and annual recruitment over the three year period was found to be extremely low (approximately two terrapins). Female diamondback terrapins in Bermuda nest almost exclusively within a limited number of sand bunkers on the golf course. Nesting commenced in late March or early April and ended in late August. Peak oviposition was observed in May and June. Clutch size averaged 5.1 eggs (range 0-10; SD 2.4) and the incubation period averaged 61.8 days (range 49-83; SD 10.5). Delayed emergence was documented, with 43.8% of the hatchlings remaining in their natal nests over the winter months. The mean annual hatching success rate was determined to be 19% (range 17.6-21; SD 1.9). Radio-telemetry was used to investigate the movements and survivorship of postemergent hatchling diamondback terrapins. The results indicated that mangrove swamps and grass-dominated marshes adjacent to the ponds are important developmental habitats for hatchlings. Yellow-crowned night herons (Nyctanassa violacea) were found to be significant predators of small terrapins during spring emergence. Small aquatic gastropods comprised 66.7% of the faecal samples analysed from the Bermudian population. Scavenged fish and vertebrate animal remains, terrestrial arthropods, polychaete worms and bivalves were consumed in lesser amounts. Sediment from the pond environment was found in 74% of the faecal samples analysed and is believed to have been incidentally ingested while foraging for the small benthic gastropods. Eco-toxicological analyses of the pond sediment, prey and terrapin eggs showed that the Bermudian diamondback terrapins live and feed in wetland habitats characterised by chronic, multifactorial contamination; principally total petroleum hydrocarbons, polycyclic aromatic hydrocarbons and a variety of heavy metals. This study found that some of those contaminants are accumulating in the gastropod prey as well as being transferred to terrapin eggs. This may be reducing the incidence of successful embryonic development for this species in Bermuda and may likely contribute to the observed low hatching rates. These collective findings indicate that the Bermudian population is very vulnerable to local extirpation.
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1. Sawfishes currently are among the most threatened elasmobranchs in the world. Only two species inhabit Atlantic waters: the largetooth sawfish (Pristis pristis) and the smalltooth sawfish (Pristis pectinata), both having suffered dramatic declines in their ranges. 2. The goal of this study was to evaluate the status of P. pristis in the Atlantic, and estimate local extinction risk based on historical and recent occurrence records. In order to accomplish these goals, a thorough search for historical and recent records of P. pristis in the Atlantic was conducted, by reviewing scientific and popular literature, museum specimens, and contacting regional scientists from the species’ historical range. 3. In total, 801 P. pristis records (1830–2009) document its occurrence in four major regions in the Atlantic: USA (n =41), Mexico and Central America (n =535), South America (n=162), and West Africa (n =48). Locality data were not available for 15 records. 4. Historical abundance centres were the Colorado-San Juan River system in Nicaragua and Costa Rica (and secondarily Lake Izabal of Guatemala), the Amazon estuary, and coastal Guinea-Bissau. 5. Currently, the species faces drastic depletion throughout its entire former range and centres of abundance. It appears to have been extirpated from several areas. The probability of extinction was highest in the USA, northern South America (Colombia to Guyane), and southern West Africa (Cameroon to Namibia). 6. Currently, the Amazon estuary appears to have the highest remaining abundance of P. pristis in the Atlantic, followed by the Colorado–San Juan River system in Nicaragua and Costa Rica and the Bissagos Archipelago in Guinea Bissau. Therefore the protection of these populations is crucial for the preservation and recovery of the species.
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Reconstrucción la de micro historia de los recicladores que viven y trabajan en la localidad de Suba en el periodo 2003-2014.
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O presente trabalho consiste na apresentação da diversidade de seláceos do Farol das Lagostas pertencente à Bacia do Cuanza. Os condrichthyes são componentes comuns da fauna aquática desde o Paleozoico. No entanto, devido à natureza cartilaginosa do esqueleto, o registo paleontológico dos mesmos restringe-se, basicamente, às partes mineralizadas como dentes, dentículos dérmicos e espinhas cefálicas O lugar Farol das Lagostas contém uma fauna de seláceos relativamente rica e variada, representada neste estudo por cerca de 1.000 dentes isolados, além de outras peças esqueléticas. Foram identificados e descritos quarenta e quatro taxa, pertencentes às seguintes ordens: Hexanchiformes, Squaliformes, Pristiophoriformes, Squatiniformes, Lamniformes, Carcharhiniformes, Rajiformes e Myliobatiformes. Trata-se de uma diversidade faunística cuja maioria dos géneros possui representantes atuais. Os Carcharhiniformes representam 53% dos taxa identificados. Estão representadas as famílias Scyliorhinidae, Triakidae, Hemigaleidae, Carcharhinidae e Sphyrnidae, com 18 espécies. Verifica-se a presença de formas bentónicas e nectónicas que indicam condições térmicas moderadas, quentes e tropicais a temperadas, que habitam frequentemente zonas costeiras. A relação faunística identificada corresponde a uma zona litoral. Ora, considerando o conjunto de dados em face da presença de fauna pelágica e dos grandes predadores, especialmente Isurus hastalis e Carcharocles megalodon, podemos admitir que existisse então um Golfo relativamente largo de uma faixa Atlântica aberta (Antunes & Balbino, 2004); ABSTRACT: Selachians from Farol the Lagostas (Cuanza Basin, Angola) The present work consists of the presentation of diversity of selachians from Farol das Lagostas, which belongs to the Cuanza Basin. The condrichthyes are a part of aquatic fauna since the Paleozoic. However, due to the nature of the cartilaginous skeleton, the paleontological registration of the same ones is restricted to mineralized parts like teeth, dermal denticles and cephalic spines. The of formation, Farol das Lagostas has a fauna of selachian relatively rich and diverse, represented in this study for around 1.000 isolated teeth, and other skeletal parts. Forty four taxa were described and identified, belonging to the following orders: Hexanchiformes, Squaliformes, Pristiophoriformes, Squatiniformes, Lamniformes, Carcharhiniformes, Rajiformes e Myliobatiformes. It’s a faunal diversity whose most genera have current representatives. The Carcharhiniformes represente 53% of the identified taxa. The represented families are Scyliorhinidae, Triakidae, Hemigaleidae, Carcharhinidae e Sphyrnidae, with 18 species. There is presence of benthic and nektonic forms that indicate moderate thermal conditions, the temperate and tropical hot, often inhabit coastal areas. The identified faunal relation corresponds to a coastal zone. So, considering the data set, due to the presence of pelagic fauna and large predators, especially Isurus hastalis e Carcharocles megalodon, we can admit that then there was a relatively large Gulf of open Atlantic range (Antunes & Balbino, 2004).
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This thesis contributes to the knowledge of temperate rocky shore ecology, with direct implications in the management and conservation of two important local marine resources that inhabit the very edge of subtidal and intertidal habitats on wave-swept rocky shores: the sessile filter feeding stalked barnacle Pollicipes pollicipes and the mobile keystone herbivore sea urchin Paracentrotus lividus. Research was conducted along gradients of wave exposure on rocky shores of Southern Europe. The abundance of P. lividus was four times higher in SW Portugal than in NW Italy. Most of the variation in urchin abundance occurred at small spatial scales, probably shaped by habitat complexity. In SW Portugal, sea urchin attachment forces while in burrows were measured and related to burrow shape, urchin size and habitat. Burrowing behaviour enhances sea urchin attachment force and might be an adaptive response to hydrodynamic stress. Abundance of P. pollicipes in SW Portugal is highly and positively related to wave exposure at local and regional scales. Predation and recruitment processes seem to be important drivers of these abundance patterns. A distribution model of P. pollicipes abundance in relation to wave exposure was developed for the SW coast of Portugal and might be used for improvement of its management and conservation. Growth of P. pollicipes was studied by applying a novel method using fluorescent calcein for marking and to estimate growth. Growth rate decreased with barnacle size and was highly variable amongst individuals, particularly in smaller barnacles. No effect of shore level on barnacle growth was detected. An assessment of the state of the fishery, conservation and management of the stalked barnacle in different regions of continental Portugal was made, highlighting an overall negative tendency of this state and recommending a change into a co-management system; Resumo: Viver no limite intertidal / subtidal: ecologia do percebe Pollicipes pollicipes e do ouriço-do-mar Paracentrotus lividus Esta tese contribui para o conhecimento da ecologia do litoral rochoso e tem implicações diretas na gestão e conservação de dois recursos marinhos locais que habitam o interface subtidal/intertidal de costas rochosas sujeitas a agitação marinha: o percebe Pollicipes pollicipes, animal séssil e filtrador e o ouriço-do-mar Paracentrotus lividus, animal móvel e herbívoro. Foram realizados vários estudos ao longo de gradientes de hidrodinamismo em costas rochosas do sul da Europa. A abundância de P. lividus foi quatro vezes superior no sudoeste de Portugal relativamente ao noroeste de Itália. Grande parte da variação na abundância de P. lividus ocorreu a pequenas escalas espaciais, provavelmente influenciada pela complexidade do habitat. A força com que o ouriço-do-mar se fixa ao substrato foi medida no terreno no sudoeste de Portugal, tendo esta sido relacionada com a forma da depressão que ocupa, o tamanho individual e o habitat. O comportamento escavador desta espécie aumenta a sua força de fixação ao substrato e poderá ser uma resposta adaptativa ao hidrodinamismo.. A abundância de P. pollicipes na costa sudoeste de Portugal, a diferentes escalas espaciais, está relacionada de forma positiva com a agitação marinha, e é influenciada pela predação e pelo recrutamento desta espécie. Foi desenvolvido um modelo de distribuição e abundância de P. pollicipes para esta costa baseado na relação com a agitação marinha, cujos resultados podem ser usados para melhorar a gestão e conservação deste recurso. Um novo método com recurso a calceina fluorescente foi desenvolvido para marcar percebes e estudar o seu crescimento. A taxa de crescimento diminuiu com o tamanho do animal, sendo altamente variável entre indivíduos, sobretudos nos de menores dimensões. O estado da apanha, conservação e gestão do percebe em diferentes regiões de Portugal Continental apresentou uma tendência global negativa, e recomenda-se uma alteração para um sistema de cogestão deste recurso.
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SummaryNational park and related forest conservation efforts tend to emanate from core areas of the world and are often imposed on rural people living on forest fringes in the least developed regions of lesser developed countries. We address the social and cultural processes that ensue when center-originatingconservation meets local people with their resource-dependent livelihoods, and how these vary under different circumstances. We examine and compare local people’s environmental andforest-related values and behaviors, using cultural models, after the establishment of national parks in two countries with very different social and environmental histories—Costa Rica and Honduras. We find that external cultural models were widely adopted by local people—hegemonic to the extent of structuring even discourse opposing conservation. Local people often expressed environmental values, but used formulaic language that suggested that these values were not well integrated with other aspects of their life and often not motivating. We pay particular attention to relationships between environmental values and livelihood values, and the varying ways that new, local environmental discourses and values emerge that mediate between these often conflicting value spheres.The recent international increase in national parks is a phenomenon of globalization, and often imposes new conservation practices and environmental values onto local people. While these new national parks have some broad public benefits that can be thought of as global, e.g. their role in preventing biodiversity loss and climate change, it is also true that few concrete benefits accrue to local people and that parks often impose great costs on local people in the form of lost land, diminished access to resources, and diminished autonomy as national governments and internationalorganizations extend into local life in new ways.These changes have serious repercussions for local people, often threatening their livelihoods and well-being in significant ways. Yet our results suggest that local people may be willing to work with park managers to co-inhabit landscapes when park managers are able to accommodate local livelihood needs.Keywords: National parks, Central America, Costa Rica, Honduras, forest conservationResumenLos parques nacionales y otros esfuerzos de conservación forestal tienden a surgir en las principales áreas núcleo del mundo, y por lo general son impuestos a los pobladores de espacios rurales que habitan franjas forestales de los países en vías de desarrollo.Este artículo se enfoca en los procesos sociales y culturales que se originan a partir de la imposición de estas áreas de conservación y sobre cómo se ve afectada la subsistencia de los pobladores que dependen de los recursos naturales de dichas áreas. También se evalúan y comparan los valores y comportamientos relacionados con el ambiente, percibidos por los pobladores con el establecimiento de parques nacionales, en dos países con historias sociales y ambientales muy diferentes como lo son Costa Rica y Honduras; para lo cual se utilizaron modelos culturales. Al respecto, se encontró que varios modelos culturales externos, que fueron ampliamente adoptados por los pobladores locales, han llegado a ser hegemónicos, afectando la conservación. Los habitantes del lugar estaban disconformes con respecto a los nuevos valores ambientales, porque estos, por un lado, no estaban adecuadamente integrados con otros aspectos de su vida, y por la escasa motivación en materia de conservación ambiental.De esta forma, se resalta la relación entre los valores ambientales y los valores de sus forma de vida;entre las nuevas formas de ruptura y los valores emergentes que median entre la esfera de valores conflictivos.El reciente aumento internacional de parques naciones es un fenómeno de globalización, y en consecuencia, impone nuevas prácticas de conservación y valores ambientales a los habitantes de estas localidades. Mientras estos nuevos parques nacionales generan algunas ventaja públicas, que pueden ser pensadas como globales (p.ej. su papel en la prevención de la pérdida de diversidad biológica y el cambio de clima), también ocasionan escasos beneficios para las comunidades, al imponer elevados costos para los pobladores locales como lo son: la pérdida de tierras, la disminución en el acceso a los recursos y la reducción de la autonomía, ya sea ante el gobierno nacional u organizaciones internaciones que extienden sus acciones políticas a la vida local en todas sus nuevas formas. Estos cambios repercuten drásticamente en los habitantes del lugar, lo cual a menudo amenaza, en general, el sustento y el bienestar, de modo significativo.Los resultados sugieren que los habitantes del lugar podrían estar dispuestos a trabajar con los gerentes del parque para co-habitar paisajes cuando éstos sean capaces de priorizar las necesidades de sobrevivencia de las formas de vida de los habitantes.Palabras clave: parques nacionales, América Central, Costa Rica, conservación forestal