636 resultados para Bathing Beaches


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As costas arenosas estão actualmente sujeitas a intensos processos erosivos, resultado tanto de actividades humanas como de processos naturais. Na costa portuguesa, este aspecto é bem evidente pelo recuo da linha de costa, pela diminuição da largura das praias, pela degradação dos sistemas dunares e principalmente, pela proliferação de obras fixas de protecção costeira ao longo da linha de costa. Desde a última metade do século passado que a Vagueira tem sido submetida a um intenso processo erosivo, resultando num acentuado recuo da linha de costa. A principal causa apontada para este facto, é a retenção de sedimentos por parte do molhe Norte do porto de Aveiro, impedindo-os de serem transportados pela deriva litoral. Existem também outras causas que contribuem para o acelerar deste processo, tais como a diminuição da quantidade de sedimentos fornecida pela deriva litoral e a retenção de sedimentos por parte das obras transversais de defesa costeira. Nos dias de hoje, a erosão costeira é um verdadeiro risco, e mesmo com a existência de obras fixas de protecção costeira, o avanço do mar é uma constante. Na Vagueira, a pressão urbana sobre o ecossistema costeiro, alterando as suas morfologias e interferindo no seu dinamismo, tem sido um factor interveniente no processo da erosão neste sector costeiro. Desde 1958, tem-se observado um recuo efectivo da linha de costa na Praia da Vagueira, e hoje em dia já se verifica a quase completa destruição do cordão dunar frontal e a construção de diques arenosos na tentativa de impedir a abertura de um novo canal de ligação entre o canal de Mira e o oceano e de proteger valores naturais irrecuperáveis. A construção da cartografia para cada ano em estudo permitiu a quantificação dos valores médios e absolutos do recuo da linha de costa na Vagueira desde 1958 a 2002. A monitorização da praia da Vagueira entre Outubro de 2002 e Outubro de 2003 permitiu a caracterização da praia emersa e apontar o comportamento geral da área em estudo.

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Aim: This study was designed to determine the prevalence of and risk factors for schistosomiasis among a group of preschool children in Malawi. Schistosomiasis burden among preschoolers in Malawi is not well documented in the literature. Methods: This study used field research (in the form of a snail survey), laboratory work (urinalysis and microscopy for parasite identification), and questionnaireguided interviews to determine the prevalence of and risk factors for urinary schistosomiasis among children, aged between 6 and 60 months, in Malengachanzi, Nkhotakota District, Malawi. Results: Urinary schistosomiasis prevalence among preschool children was 13%. Of the factors evaluated, only age (P = 0.027) was statistically significantly associated with urinary schistosomiasis risk. Four-year-old preschool children were five times more likely to contract urinary schistosomiasis than two-year-old children (odds ratio [OR] = 5.255; 95% confidence interval [CI] = 1.014-27.237; P = 0.048). Increased contact with infested water among older children likely explains much of their increased risk. Infestation was evidenced by the presence of infected Bulinus globosus snails in the water contact points surveyed. Multiple regression analysis showed that visiting water contact sites daily (OR = 0.898, 95% CI = 0.185-4.350, P = 0.894), bathing in these sites (OR = 9.462, 95% CI = 0.036-0.00, P = 0.430) and lack of knowledge, among caregivers, regarding the causes of urinary schistosomiasis (OR = 0.235, 95% CI = 0.005-1.102, P = 0.066) posed statistically insignificant risk increases for preschoolers contracting urinary schistosomiasis. Conclusions: Urinary schistosomiasis was prevalent among preschool children in Malengachanzi, Nkhotakota District. Contact with infested water puts these children and the general population at risk of infection and reinfection. Inclusion of preschool children in treatment programmes should be considered imperative, along with safe treatment guidelines. To prevent infection, the population in the area should be provided with health education and safe alternative water sources.

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A indústria turística tem-se focado na diversificação, de forma contínua, tornando-se um dos motores fundamentais para o progresso dos setores económicos de um país. Para tal, o desenvolvimento de um Produto Turístico de sucesso que visa oferecer ao público-alvo uma experiência memorável para satisfazer o seu desejo é essencial para que este consumidor venha a visitar um determinado destino. A nova era digital transformou a estratégia de marketing das empresas e esta nova conjuntura tem vindo a contribuir para o crescimento exponencial e para o desenvolvimento das técnicas e ferramentas que permitem promover a comunicação entre a empresa/marca e o consumidor, aspeto em que o marketing digital tem desempenhado um papel importante. Em tempos de valorização da experiência turística, o setor turístico de Cabo Verde pouco tem explorado e não tem tirado grande partido do marketing digital para dar a conhecer as potencialidades e as maravilhas do destino enquanto produto turístico, que ainda tem muito por descobrir por parte dos consumidores nacionais e internacionais. Como objetivos deste plano de comunicação Visit Cabo Verde pretende-se aumentar a notoriedade da marca Cabo Verde e captar novos turistas através da promoção de 4 ilhas: Santiago, São Vicente, Santo Antão e Boavista dividindo-as em 3 (três) subprodutos - cultura, natureza e praia. Com a realização deste projeto prevê-se que Cabo Verde atinja o público-alvo definido através da conceção das campanhas relevantes para os potenciais turistas e aumentar o fluxo dos turistas no arquipélago. As limitações deste plano de comunicação incidem sobre a variável produto que não é controlável, procurando este plano uma linha de orientação para a variável comunicação.

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Background: Assessing the chemical or bacterial contamination in marine waters and sediments is a very common approach to evaluate marine pollution and associated risks. However, toxicity and organic pollution of beach sands have not yet been considered, except in adjacent waters. In the present study, the toxicity and the chemical contamination of natural beach sands collected 20 m from the shoreline at two sites located on the Mediterranean Sea (Marseille and La Marana, Corsica) were studied. Results: Up to 16.93% (net percentage) abnormal or dead larvae was observed in elutriates prepared from the urban beach sand sample (Marseille); no significant toxicity was observed in the sample collected from the reference beach in La Marana. Results of Fourier transform infrared spectroscopy analyses revealed that no microplastics were present in either of the samples. Several polycyclic aromatic hydrocarbons [PAHs] in both samples and a larger number of individual PAHs in the urban sample than in the sample collected from the reference beach were detected. In addition, the antioxidant dioctyldiphenylamine was detected in both beach sand samples, whereby a higher concentration was found in La Marana than in Marseille. Calculated PAH concentrations in elutriates were generally higher than measured ones. Conclusions: The results of this preliminary study provide evidence of toxicity and the presence of organic trace contaminants in beach sands from France. According to our results, monitoring using a combination of biotests and chemical analyses is recommended, especially of sediments from beaches abandoned to urban and industrial areas.

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Experimental analyses of hermit crabs and their preferences for shells are essential to understand the intrinsic relationship of the crabs' dependence on shells, and may be useful to explain their shell use pattern in nature. The aim of this study was to evaluate the effect of crab species and site on the pattern of shell use, selection, and preference in the south-western Atlantic hermit crabs Pagurus brevidactylus and Pagurus criniticornis, comparing sympatric and allopatric populations. Differently from the traditional approach to evaluate shell preference by simply determining the shell selection pattern (i.e., the number of shells of each type selected), preference was defined (according to [Liszka, D., Underwood, AJ., 1990. An experimental design to determine preferences for gastropod shells by a hermit-crab. J. Exp. Mar. Biol. Ecol., 137(1), 47-62]) by the comparison of the number of crabs changing for a particular shell type when three options were given (Cerithium atratum, Morula nodulosa, and Tegula viridula) with the number of crabs changing for this same type when only this type was offered. The effect of crab species was tested at Cabelo Gordo Beach, where P. brevidacrylus was found occupying shells of C. atratum, M. nodulosa, and T viridula in similar frequencies, whereas P. criniticornis occupied predominantly shells of C atratum. In laboratory experiments the selection patterns of the two hermit-crab species for these three gastropods were different, with P criniticornis selecting mainly shells of C atratum, and R brevidactylus selecting more shells of M. nodulosa. The shell preference was also dependent on crab species, with P. criniticornis showing a clear preference for shells of C atratum, whereas P. brevidactylus did not show a preference for any of the tested shells. The effect of site was tested for the two species comparing data from Cabelo Gordo to Preta (P brevidactylus) and Araca beaches (P. criniticornis). The pattern of shell use, selection, and preference was demonstrated to be dependent on site only for P. brevidactylus. The results also showed that the shell use pattern of P criniticornis can be explained by its preference at both sites, whereas for P. brevidactylus it occurred only at Cabelo Gordo, where the absence of preference was correlated with the similar use of the three gastropod species studied. Finally, the results showed that the shell selection pattern cannot be considered as a measure of shell preference, since it overestimates crab selectivity. (C) 2009 Elsevier B.V. All rights reserved.

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Dependence of some species on landscape structure has been proved in numerous studies. So far, however, little progress has been made in the integration of landscape metrics in the prediction of species associated with coastal features. Specific landscape metrics were tested as predictors of coastal shape using three coastal features of the Iberian Peninsula (beaches, capes and gulfs) at different scales. We used the landscape metrics in combination with environmental variables to model the niche and find suitable habitats for a seagrass species (Cymodocea nodosa) throughout its entire range of distribution. Landscape metrics able to capture variation in the coastline enhanced significantly the accuracy of the models, despite the limitations caused by the scale of the study. We provided the first global model of the factors that can be shaping the environmental niche and distribution of C. nodosa throughout its range. Sea surface temperature and salinity were the most relevant variables. We identified areas that seem unsuitable for C. nodosa as well as those suitable habitats not occupied by the species. We also present some preliminary results of testing historical biogeographical hypotheses derived from distribution predictions under Last Glacial Maximum conditions and genetic diversity data.

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The importance of nourishment processes on the beaches of Mediterranean Sea has been increasing since the end of the 20th century due to its socio-economical awareness (tourismboost) and environmental implications (possible impact on Posidonia oceanica meadows and important processes of dredging and earth movements). However, in many cases, and especially in eastern Spain, relevant actions have been made which had caused that, after 20 years, the beaches in which these works were carried out will be in a similar situation with the original one. The present study analyzed the Poniente Beach (Benidorm, Spain), a beach where the nourishment works of 1991 have caused the disappearance of the Posidonia oceanica meadows and a regression process that will lead to the disappearance of the beach in a few years. To this end, data from bathymetry, georeferenced orthophotos, grain size analysis and swell study have been obtained and analyzed, understanding the importance of the works done to be consistent with the environment in which they were developed, and providing a work process which can ensure the existence of the nourished beach starting from the maintenance of Posidonia oceanica meadows.

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The so-called "residential tourism" came to intensify the previous occupation of the coastal zones, characterized by traditional beach houses, and brought significant consequences for their spatial configuration, and especially for its scenic value of the landscape. Although there is the intention to regulate the activities of enterprising groups by some legal instruments to control the use and occupation of land, and to contain some negative effects, the actions of government are still inefficient in trying to follow the implications on the landscape from the accelerated growth of the real estate and touristic sectors. Supported in the speech of economic development and income generation, public managers prioritize areas to attract tourists to the detriment of preserving important physical attributes of the natural environment that contribute significantly to the quality of life. The result can be noticed in the use of natural elements as one of the major components in the land valorization, and in the immediate attraction of investors and enterprising. Therefore, the objective of this work is to contribute to the debate on the landscape preservation a little detailed thematic in view of their relevance in the current context - by indicating subsidies to the creation of a methodology for the evaluation and protection of coastal zones that may assist the government in creating new instruments, and better prepare it in control of the occupation of these areas. For such, was followed two ways to analysis: the indirect method and the direct method. The first is grounded in the evaluation of landscape attributes, which is based on the work of Raquel Tardin (2008) and Eduardo Cuesta, Encarnación Algarra and Isabel Pastor (2001). The second, based on the research of Leticia and Carlos Hardt (2010) and on the concepts of phenomenology - expressed by Antonio Christofoletti (1985) and Yi-Fu Tuan (1983) - considers the population perspective on the quality of the natural scenery. Developed through cartographic materials, photographic collections and quantitative tables, this dissertation utilized as a case study the beaches of Barra de Tabatinga and Camurupim, located in the city of Nísia Floresta/RN. Despite already being sighted spaces of advanced stage of landscape degradation in these locations, areas of remarkable scenic value can still be found, what reinforce the urgency in adopting preservationists actions. The absence of laws focused on the management and protection of the landscape singularities associated with the inefficiency of the government to invigilate the land occupation in coastal zones, encourage the excessive action of the real estate-tourism, and consequently make the government the main responsible for the environmental and landscape impacts in these areas - by its omission or by their connivance. Therefore, the legislation permeates this entire process and constitutes itself as the most effective way to guarantee the right to the landscape to present and future generations. Are also pointed some important considerations to build a methodology, especially concerning possibilities of improvements and adaptations of its applicability in each case

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The general objective of this thesis has been seasonal monitoring (quarterly time scale) of coastal and estuarine areas of a section of the Northern Coast of Rio Grande do Norte, Brazil, environmentally sensitive and with intense sediment erosion in the oil activities to underpin the implementation of projects for containment of erosion and mitigate the impacts of coastal dynamics. In order to achieve the general objective, the work was done systematically in three stages which consisted the specific objectives. The first stage was the implementation of geodetic reference infrastructure for carrying out the geodetic survey of the study area. This process included the implementation of RGLS (Northern Coast of the RN GPS Network), consisting of stations with geodetic coordinates and orthometric heights of precision; positioning of Benchmarks and evaluation of the gravimetric geoid available, for use in GPS altimetry of precision; and development of software for GPS altimetry of precision. The second stage was the development and improvement of methodologies for collection, processing, representation, integration and analysis of CoastLine (CL) and Digital Elevation Models (DEM) obtained by geodetic positioning techniques. As part of this stage have been made since, the choice of equipment and positioning methods to be used, depending on the required precision and structure implanted, and the definition of the LC indicator and of the geodesic references best suited, to coastal monitoring of precision. The third step was the seasonal geodesic monitoring of the study area. It was defined the execution times of the geodetic surveys by analyzing the pattern of sediment dynamics of the study area; the performing of surveys in order to calculate and locate areas and volumes of erosion and accretion (sandy and volumetric sedimentary balance) occurred on CL and on the beaches and islands surfaces throughout the year, and study of correlations between the measured variations (in area and volume) between each survey and the action of the coastal dynamic agents. The results allowed an integrated study of spatial and temporal interrelationships of the causes and consequences of intensive coastal processes operating in the area, especially to the measurement of variability of erosion, transport, balance and supply sedimentary over the annual cycle of construction and destruction of beaches. In the analysis of the results, it was possible to identify the causes and consequences of severe coastal erosion occurred on beaches exposed, to analyze the recovery of beaches and the accretion occurring in tidal inlets and estuaries. From the optics of seasonal variations in the CL, human interventions to erosion contention have been proposed with the aim of restoring the previous situation of the beaches in the process of erosion.

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The objective of this Doctoral Thesis was monitoring, in trimestral scale, the coastal morphology of the Northeastern coast sections of Rio Grande do Norte State, in Brazil, which is an area of Potiguar Basin influenced by the oil industry activities. The studied sections compose coastal areas with intense sedimentary erosion and high environmental sensitivity to the oil spill. In order to achieve the general objective of this study, the work has been systematized in four steps. The first one refers to the evaluation of the geomorphological data acquisition methodologies used on Digital Elevation Model (DEM) of sandy beaches. The data has been obtained from Soledade beach, located on the Northeastern coast of Rio Grande Norte. The second step has been centered on the increasing of the reference geodetic infrastructure to accomplish the geodetic survey of the studied area by implanting a station in Corta Cachorro Barrier Island and by conducting monitoring geodetic surveys to understand the beach system based on the Coastline (CL) and on DEM multitemporal analysis. The third phase has been related to the usage of the methodology developed by Santos; Amaro (2011) and Santos et al. (2012) for the surveying, processing, representation, integration and analysis of Coastlines from sandy coast, which have been obtained through geodetic techniques of positioning, morphological change analysis and sediment transport. The fourth stage represents the innovation of surveys in coastal environment by using the Terrestrial Laser Scanning (TLS), based on Light Detection and Ranging (LiDAR), to evaluate a highly eroded section on Soledade beach where the oil industry structures are located. The evaluation has been achieved through high-precision DEM and accuracy during the modeling of the coast morphology changes. The result analysis of the integrated study about the spatial and temporal interrelations of the intense coastal processes in areas of building cycles and destruction of beaches has allowed identifying the causes and consequences of the intense coastal erosion in exposed beach sections and in barrier islands

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Coastal birds are critical ecosystem constituents on sandy shores, yet are threatened by depressed reproductive success resulting from direct and indirect anthropogenic and natural pressures. Few studies examine clutch fate across the wide range of environments experienced by birds; instead, most focus at the small site scale. We examine survival of model shorebird clutches as an index of true clutch survival at a regional scale (∼200 km), encompassing a variety of geomorphologies, predator communities, and human use regimes in southeast Queensland, Australia. Of the 132 model nests deployed and monitored with cameras, 45 (34%) survived the experimental exposure period. Thirty-five (27%) were lost to flooding, 32 (24%) were depredated, nine (7%) buried by sand, seven (5%) destroyed by people, three (2%) failed by unknown causes, and one (1%) was destroyed by a dog. Clutch fate differed substantially among regions, particularly with respect to losses from flooding and predation. ‘Topographic’ exposure was the main driver of mortality of nests placed close to the drift line near the base of dunes, which were lost to waves (particularly during storms) and to a lesser extent depredation. Predators determined the fate of clutches not lost to waves, with the depredation probability largely influenced by region. Depredation probability declined as nests were backed by higher dunes and were placed closer to vegetation. This study emphasizes the scale at which clutch fate and survival varies within a regional context, the prominence of corvids as egg predators, the significant role of flooding as a source of nest loss, and the multiple trade-offs faced by beach-nesting birds and those that manage them.

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Exploratory investigations of optimal sampling designs are a critical component of the decision-making process in ecology where inherent natural variation can lead to erroneous conclusions if left unexamined. Pilot studies and exploratory analyses that investigate the precision of sampling regimes may reduce the chances of erroneous results and can be used to optimise processing time in larger ecological research programs. In our study, we calculated optimal precision estimates for sampling macroinvertebrates and ichthyofauna in surf-zone wrack accumulations by investigating the precision of the mean for sub-samples of seine nets and also for the number of replicate seine nets to guide future sampling regimes. We discovered that the processing time for individual seine net samples could be reduced by 50% using sub-sampling and that time to process replicate seine net samples could be reduced by 25% while maintaining acceptable precision. In future, we suggest that the use of pilot studies with similar exploratory approaches should be less of an exception and more a critical component of ecological investigations, particularly in under-studied or newly-developing areas of research. Further, these types of exploratory approaches are crucially important in a variety of extremely patchy environments where variability is likely to be high.

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Background: The number of centenarians is rapidly increasing in Europe. In Portugal, it has almost tripled over the last 10 years and constitutes one of the fastest-growing segments of the population. This paper aims to describe the health and sociodemographic characteristics of Portuguese centenarians as given in the 2011 census and to identify sex differences. Methods: All persons living in Portugal mainland and Madeira and Azores islands aged 100 years old at the time of the 2011 census (N = 1,526) were considered. Measures include sociodemographic characteristics and perceived difficulties in six functional domains of basic actions (seeing, hearing, walking, cognition, self-care, and communication) as assessed by the Portuguese census official questionnaires. Results: Most centenarians are women (82.1 %), widowed (82 %), never attended school (51 %), and live in private households (71 %). The majority show major constraints in seeing (67.4 %), hearing (72.3 %), and particularly in their mobility (83.7 % cannot/have great difficulties in walking/climbing stairs and 80.7 % in bathing/dressing). In general, a better outcome was found for reported memory/concentration and understanding, with 39.1 % and 42.5 % presenting no or mild difficulty, respectively. Top-level functioning (no/mild difficulties in all dimensions concurrently) was observed in a minority of cases (5.96 %). Women outnumber men by a ratio of 4.6, and statistically significant differences were found between men and women for all health-related variables, with women presenting a higher percentage of difficulties. Conclusion: Portuguese centenarians experience great difficulties in sensory domains and basic daily living activities, and to a lesser extent in cognition and communication. The obtained profile, though self-reported, is important in considering the potential of social and family participation of this population regardless of their functional and sensory limitations. Based on the observed differences between men and women, gender-specific and gender-sensitive interventions are recommended in order to acknowledge women’s worse overall condition.

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Umbrella species are rarely selected systematically from a range of candidate species. On sandy beaches, birds that nest on the upper beach or in dunes are threatened globally and hence are prime candidates for conservation intervention and putative umbrella species status. Here we use a maximum-likelihood, multi-species distribution modeling approach to select an appropriate conservation umbrella from a group of candidate species occupying similar habitats. We identify overlap in spatial extent and niche characteristics among four beach-nesting bird species of conservation concern, American oystercatchers (Haematopus palliatus), black skimmers (Rynchops niger), least terns (Sterna antillarum) and piping plovers (Charadrius melodus), across their entire breeding range in New Jersey, USA. We quantify the benefit and efficiency of using each species as a candidate umbrella on the remaining group. Piping plover nesting habitat encompassed 86% of the least tern habitat but only 15% and 13% of the black skimmer and American oystercatcher habitat, respectively. However, plovers co-occur with all three species across 66% of their total nesting habitat extent (~ 649 ha), suggesting their value as an umbrella at the local scale. American oystercatcher nesting habitat covers 100%, 99% and 47% of piping plover, least tern and black skimmer habitat, making this species more appropriate conservation umbrellas at a regional scale. Our results demonstrate that the choice of umbrella species requires explicit consideration of spatial scale and an understanding of the habitat attributes that an umbrella species represents and to which extent it encompasses other species of conservation interest. Notwithstanding the attractiveness of the umbrella species concept, local conservation interventions especially for breeding individuals in small populations may still be needed.