281 resultados para DUNES


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Through the nineteenth century, it was constant in the discourse of the local norte-rio-grandenses (Natal city, Brazil) administrators, the appeal for subsidy to the central government for the works of the port of Natal upgrade. The port in the capital, the main route of the Rio Grande do Norte communication, because of the limitations attached to it, as the dunes surrounding the city spreading sand in the riverbed, and several reefs located along the coast, did not allow the entry in his berth larger ships. These difficulties brought major problems the province, who could not hold the flow of production coming from the inside, resulting in the north of Rio Grande political scene, questioning the centrality of Christmas position in the province. Only Republican scheme had been approved credit by the federal government for the improvement works of the port. The port became the Republican political discourse Potiguar one of the main promises to bring "progress" the Potiguar land, being placed as a central issue of which depend on the "future" of the state. The objective of this study is to analyse the emergence of a new port concept in speeches and interventions of the local ruling groups in the early twentieth century. We analyse the emergence of a modern notion of port, marked by the organizing effort, rationalization and regulation of port activities by the state, and the new relationship assumed by the harbour front to the city resulting from this new perception. The port has become for local leaders to groups of capital "waiting room", requiring change of the composition of urban space for integrating the port to the city. The Port of Natal became endowed with a pedagogical function, incorporating the urban fabric, codes, values and practices considered by local managers as modern and civilized. This new city space, considered a "waiting room", caused conflicts between the local ruling groups and influential figures in the Potiguar political field, which sought to encourage with the process of organizing the harbour front undesirable regarded figures in the city views as an impediment to the image of progress and modernity that the dominant groups intended to expose the port.

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Environmental Sustainability is a very important factor for the Tourist Development of the localities, which should be protected and preserved so many other generations goers enjoy the experiences in their paradisiacal landscapes. The objective of the present study is to analyze the sustainability of the tourist destination of Jenipabu Beach, situated in a conservation area on the northern coast of Rio Grande do Norte state, in the city of Extremoz, 20 km from the center of the Capital Natal, being of great state tourist importance for having the most famous Dunes park in the region. There are several regulars and their proper groups in a tourist area, and the differences in these perceptions about the relationship of certain factors occurring on site, can determine how sustainable the same or its sustainability index is. This research used an Ecotourism Sustainability Indicator System (SEIS) to Tsaur, et al (2006), to assist in the verification of this index, in use methods of exploratory and descriptive research, where the data were collected through a questionnaire applied close to 151 attendees divided among residents, traders and visitors, directly by the author in Jenipabu in August and September 2015. The tabulation, analysis and interpretation of data were taken from the assistance of the technical factor analysis of statistics and ONEWAY ANOVA, which conducted by IBM SPSS software STATISTICS 20. The main findings were, identifying 14 relevant sustainability factors, of which 6 coincide with the indicator model used and 8 are new, as well as verification that Jenipabu is a destination with strong economic dependence of the Tourism, with various impacts of this community, which does not recognize the benefits that the Environmental Protection Area (APA) can bring to this and to the locality tourism. In conclusion on differences in perceptions of the regulars that the studied region Beach has low Sustainability and requires the development of various projects and actions for improvement.

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Sediment dynamics on a storm-dominated shelf (western Bay of Plenty, New Zealand) were mapped and analyzed using the newly developed multi-sensor benthic profiler MARUM NERIDIS III. An area of 60 km × 7 km between 2 and 35 m water depth was surveyed with this bottom-towed sled equipped with a high-resolution camera for continuous close-up seafloor photography and a CTD with connected turbidity sensor. Here we introduce our approach of using this multi-parameter dataset combined with sidescan sonography and sedimentological analyses to create detailed lithofacies and bedform distribution maps and to derive regional sediment transport patterns. For the assessment of sediment distribution, photographs were classified and their spatial distribution mapped out according to associated acoustic backscatter from a sidescan sonar. This provisional map was used to choose target locations for surficial sediment sampling and subsequent laboratory analysis of grain size distribution and mineralogical composition. Finally, photographic, granulometric and mineralogical facies were combined into a unified lithofacies map and corresponding stratigraphic model. Eight distinct types of lithofacies with seawards increasing grain size were discriminated and interpreted as reworked relict deposits overlain by post-transgressional fluvial sediments. The dominant transport processes in different water depths were identified based on type and orientation of bedforms, as well as bottom water turbidity and lithofacies distribution. Observed bedforms include subaquatic dunes, coarse sand ribbons and sorted bedforms of varying dimensions, which were interpreted as being initially formed by erosion. Under fair weather conditions, sediment is transported from the northwest towards the southeast by littoral drift. During storm events, a current from the southeast to the northweast is induced which is transporting sediment along the shore in up to 35 m water depth. Shorewards oriented cross-shore transport is taking place in up to 60 m water depth and is likewise initiated by storm events. Our study demonstrates how benthic photographic profiling delivers comprehensive compositional, structural and environmental information, which compares well with results obtained by traditional probing methods, but offers much higher spatial resolution while covering larger areas. Multi-sensor benthic profiling enhances the interpretability of acoustic seafloor mapping techniques and is a rapid and economic approach to seabed and habitat mapping especially in muddy to sandy facies.

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Beach and salt marsh vegetation of the Uummannaq District, northern West Greenland (c. 70°15' N - 72° N, 49° W - 54° W) was studied 1998 according to the Braun-Blanquet phytosociological approach. Habitat analyses included soil chemistry. Such vegetation locally occurs and is not developed over extensive areas. On gravely stony beaches a Mertensia maritima ssp. maritima community occurs, while a Honckenya peploides var. diffusa community is confined to sandy beaches. The association Honckenyo diffusae-Elymetum mollis Thannh. 1975 is confined to sandy shore walls and low dunes. All vegetation types are assigned to the alliance Honckenyo- Elymion arenariae Tx. 1966, which again is a unit of the order Honckenyo- Elymetalia arenariae Tx. 1966, which is sub ordered to the class Honckenyo-Elymetea arenariae Tx. 1966. On fine sediments along sheltered coasts salt marsh vegetation is locally developed mainly on fiord deltas and outwash plains of small rivers and streams. A distinct zonation pattern in vegetation can be observed from the lower to upper salt marsh: Puccinellietum phryganodis Hadac 1946 association, Caricetum subspathaceae Hadac 1946 association, Caricetum ursinae Hadac 1946 association (all assigned to the alliance Puccinellion phryganodis Hadac 1946) and Festuco-Caricetum glareosae Nordh. 1954 association (assigned to the alliance Armerion maritimae Br.-Bl. et de Leeuw 1936). Both alliances are units of the order Glauco- Puccinellietalia Beeftink et Westhoff in Beeftink 1965, which is assigned to the class Asteretea tripolii Westhoff et Beeftink in Beeftink 1962. TWINSPAN and CCA support the vegetation classification and the CCA with soil chemistry parameters shows that salinity (related to position above MHW) and Ncontent are strongly correlated with the floristical differentiation of the vegetation of the Honckenyo-Elymetea class. In the Asteretea tripolii class, position above MHW (negatively correlated with pH, conductivity and Clcontent) and fresh water supply are likely the main factors, which affect vegetation differentiation. A synoptic survey of vegetation types from Greenland based on published phytosociological tables is presented and distribution of the vegetation types is addressed, just as their position in a circumpolar context. Moreover a Cochlearia groenlandica-Melandrium triflorum community is described as a new vegetation type, occurring on shallow soil on cliffs influenced by salt spray.

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The Australian southern continental margin is the world’s largest site of cool-water carbonate deposition, and the Great Australian Bight is its largest sector. The Eyre Peninsula is fringed by coastal beaches with aeolianites and marks the eastern edge of the Great Australian Bight. Five shoreline transects of varying lengths spanned a 150km longitudinal distance and at each the intertidal, beach, dune and secondary dune environments were sampled, for a total of 18 samples. Sediments are a mixture of modern, relict, and Cenozoic carbonates, and quartz grains. Carbonate aeolianites on the western Eyre Peninsula are mostly composed of modern carbonate grains: predominantly molluscs (23-33%) and benthic foraminifera (10-26%), locally abundant coralline algae (3-28%), echinoids (2-22%), and bryozoans (2-14%). Cenozoic grain abundance ranges from 1-6% whereas relict grain abundance ranges from 0-17%. A southward increase in bryozoan particles correlates with a nutrient element abundance and decrease in temperature due to a large seasonal coastal upwelling system that drives 2-3 major upwelling events per year, bringing cold, nutrient rich, Sub-Antarctic Surface Water (<12°C) onto the shelf. In southern, mostly wind protected locations, the beach and dune sediment compositions are similar, indicating that wind energy has successfully carried all sediment components of the beach into the adjacent dunes. In northern, exposed locations, the composition is not the same everywhere, and trends indicate that relative wind energy has the ability to impact grain composition through preferential wind transport. Aeolianite composition is therefore a function of both upwelling and the degree of coastal exposure.

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The southeastern coast of South Australia contains a spectacular and world-renown suite of Quaternary calcareous aeolianites. This study is focused on the provenance of components in the Holocene sector of this carbonate breach-dune succession. Research was carried out along seven transects from ~30 meters water depth offshore across the beach and into the dunes. Offshore sediments were acquired via grab sampling and SCUBA. Results indicate that dunes of the southern Lacepede and Otway coasts in particular are mostly composed of modern invertebrate and calcareous algal allochems. The most numerous grains are from molluscs, benthic foraminifera, coralline algae, echinoids, and bryozoans. These particles originate in carbonate factories such as macroalgal forests, rocky reefs, seagrass meadows, and low-relief seafloor rockgrounds. The incorporation of carbonate skeletons into coastal dunes, however, depends on a combination of; 1) the infauna within intertidal and nearshore environments, 2) the physical characteristics of different allochems and their ability to withstand fragmentation and abrasion, 3) the wave and swell climate, and 4) the nature of aeolian transport. Most aeolian dune sediment is derived from nearshore and intertidal carbonate factories. This is particularly well illustrated by the abundance of robust infaunal bivalves that inhabit the nearshore sands and virtual absence of bryozoans that are common as sediment particles in water depths > 10mwd. Thus, the calcareous aeolianites in this cool-water carbonate region are not a reflection of the offshore marine shelf factories, but more a product of shallow nearshore-intertidal biomes.

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The study of the Upper Jurassic-Lower Cretaceous deposits (Higueruelas, Villar del Arzobispo and Aldea de Cortés Formations) of the South Iberian Basin (NW Valencia, Spain) reveals new stratigraphic and sedimentological data, which have significant implications on the stratigraphic framework, depositional environments and age of these units. The Higueruelas Fm was deposited in a mid-inner carbonate platform where oncolitic bars migrated by the action of storms and where oncoid production progressively decreased towards the uppermost part of the unit. The overlying Villar del Arzobispo Fm has been traditionally interpreted as an inner platform-lagoon evolving into a tidal-flat. Here it is interpreted as an inner-carbonate platform affected by storms, where oolitic shoals protected a lagoon, which had siliciclastic inputs from the continent. The Aldea de Cortés Fm has been previously interpreted as a lagoon surrounded by tidal-flats and fluvial-deltaic plains. Here it is reinterpreted as a coastal wetland where siliciclastic muddy deposits interacted with shallow fresh to marine water bodies, aeolian dunes and continental siliciclastic inputs. The contact between the Higueruelas and Villar del Arzobispo Fms, classically defined as gradual, is also interpreted here as rapid. More importantly, the contact between the Villar del Arzobispo and Aldea de Cortés Fms, previously considered as unconformable, is here interpreted as gradual. The presence of Alveosepta in the Villar del Arzobispo Fm suggests that at least part of this unit is Kimmeridgian, unlike the previously assigned Late Tithonian-Middle Berriasian age. Consequently, the underlying Higueruelas Fm, previously considered Tithonian, should not be younger than Kimmeridgian. Accordingly, sedimentation of the Aldea de Cortés Fm, previously considered Valangian-Hauterivian, probably started during the Tithonian and it may be considered part of the regressive trend of the Late Jurassic-Early Cretaceous cycle. This is consistent with the dinosaur faunas, typically Jurassic, described in the Villar del Arzobispo and Aldea de Cortés Fms.

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Les écosystèmes dunaires remplissent plusieurs fonctions écologiques essentielles comme celle de protéger le littoral grâce à leur capacité d’amortissement face aux vents et vagues des tempêtes. Les dunes jouent aussi un rôle dans la filtration de l’eau, la recharge de la nappe phréatique, le maintien de la biodiversité, en plus de présenter un attrait culturel, récréatif et touristique. Les milieux dunaires sont très dynamiques et incluent plusieurs stades de succession végétale, passant de la plage de sable nu à la dune bordière stabilisée par l’ammophile à ligule courte, laquelle permet aussi l’établissement d’autres herbacées, d’arbustes et, éventuellement, d’arbres. Or, la survie de ces végétaux est intimement liée aux microorganismes du sol. Les champignons du sol interagissent intimement avec les racines des plantes, modifient la structure des sols, et contribuent à la décomposition de la matière organique et à la disponibilité des nutriments. Ils sont donc des acteurs clés de l’écologie des sols et contribuent à la stabilisation des dunes. Malgré cela, la diversité et la structure des communautés fongiques, ainsi que les mécanismes influençant leur dynamique écologique, demeurent relativement méconnus. Le travail présenté dans cette thèse explore la diversité des communautés fongiques à travers le gradient de succession et de conditions édaphiques d’un écosystème dunaire côtier afin d’améliorer la compréhension de la dynamique des sols en milieux dunaires. Une vaste collecte de données sur le terrain a été réalisée sur une plaine de dunes reliques se trouvant aux Îles de la Madeleine, Qc. J’ai échantillonné plus de 80 sites répartis sur l’ensemble de ce système dunaire et caractérisé les champignons du sol grâce au séquençage à haut débit. Dans un premier temps, j’ai dressé un portait d’ensemble des communautés fongiques du sol à travers les différentes zones des dunes. En plus d’une description taxonomique, les modes de vie fongiques ont été prédits afin de mieux comprendre comment les variations au niveau des communautés de champignons du sol peuvent se traduire en changements fonctionnels. J’ai observé un niveau de diversité fongique élevé (plus de 3400 unités taxonomiques opérationnelles au total) et des communautés taxonomiquement et fonctionnellement distinctes à travers un gradient de succession et de conditions édaphiques. Ces résultats ont aussi indiqué que toutes les zones des dunes, incluant la zone pionière, supportent des communautés fongiques diversifiées. Ensuite, le lien entre les communautés végétales et fongiques a été étudié à travers l’ensemble de la séquence dunaire. Ces résultats ont montré une augmentation claire de la richesse spécifique végétale, ainsi qu’une augmentation de la diversité des stratégies d’acquisition de nutriments (traits souterrains lié à la nutrition des plantes, soit mycorhizien à arbuscule, ectomycorhizien, mycorhizien éricoide, fixateur d’azote ou non spécialisé). J’ai aussi pu établir une forte corrélation entre les champignons du sol et la végétation, qui semblent tous deux réagir de façon similaire aux conditions physicochimiques du sol. Le pH du sol influençait fortement les communautés végétales et fongiques. Le lien observé entre les communautés végétales et fongiques met l’emphase sur l’importance des interactions biotiques positives au fil de la succession dans les environnements pauvres en nutriments. Finalement, j’ai comparé les communautés de champignons ectomycorhiziens associées aux principales espèces arborescentes dans les forêts dunaires. J’ai observé une richesse importante, avec un total de 200 unités taxonomiques opérationnelles ectomycorhiziennes, appartenant principalement aux Agaricomycètes. Une analyse de réseaux n’a pas permis de détecter de modules (c'est-à-dire des sous-groupes d’espèces en interaction), ce qui indique un faible niveau de spécificité des associations ectomycorhiziennes. De plus, je n’ai pas observé de différences en termes de richesse ou de structure des communautés entre les quatre espèces hôtes. En conclusion, j’ai pu observer à travers la succession dunaire des communautés diversifiées et des structures distinctes selon la zone de la dune, tant chez les champignons que chez les plantes. La succession semble toutefois moins marquée au niveau des communautés fongiques, par rapport aux patrons observés chez les plantes. Ces résultats ont alimenté une réflexion sur le potentiel et les perspectives, mais aussi sur les limitations des approches reposant sur le séquençage à haut-débit en écologie microbienne.

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Cette thèse défend les mérites d’une lecture cyborgienne de l’oeuvre de science-fiction de Frank Herbert, Dune, où la vision particulière des sciences et technologies nous permet d’interpréter plusieurs personnages en tant que réitération Nouvelle Vague du cyborg. Publié en 1965, Dune introduit des personnages féminins atypiques pour cette époque compte tenu de leurs attributs tels qu’une capacité intellectuelle accrue, une imposante puissance de combat et une immunité manifeste contre la faiblesse émotionnelle. Cependant, le roman reste ambivalent en ce qui concerne ces femmes : en dépit de leurs qualités admirables, elles sont d’autre part caractérisées par des stéréotypes régressifs, exposants une sexualité instinctive, qui les confinent tout au mieux aux rôles de mère, maitresse ou épouse. Finalement, dans le roman, elles finissent par jouer le rôle du méchant. Cette caractérisation se rapproche beaucoup de celle du cyborg femelle qui est d’usage courant dans les productions de science fiction pour le grand public des décennies plus récentes. Par conséquent, cette thèse défend qu’une lecture cyborgienne de Dune complète et accroisse une analyse sexospécifique, car cette approche comporte une théorisation essentielle des réactions à l’égard de la technologie qui, selon Evans, sont entretissées dans la réaction patriarcale de ce roman à l’égard des femmes. Bien que ces créatures fictives ne soient pas encore communes à l’époque de la rédaction de Dune, Jessica et certains autres personnages du roman peuvent néanmoins être considérés comme exemples primitifs des cyborgs, parce qu’ils incarnent la science et la technologie de leur culture et qu’ils possèdent d’autres éléments typiques du cyborg. L’hypothèse propose que la représentation des femmes dans Dune ne découle pas seulement de l’attrait pour le chauvinisme ou la misogynie, mais qu’elle est en fait grandement influencée par la peur de la technologie qui est transposée sur la femme comme c’est couramment le cas dans la littérature cyborg subséquente. Ainsi, ce roman annonce le futur sous-genre cyborg de la science-fiction.

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The Late Glacial and Holocene landscape development in the vicinity of the River Elbe near Neuhaus, Lower Saxony, was studied during geological mapping of the area. The geological and geobotanical methods used in these investigations were chosen to cope with the difficulties which arise during research on Quaternary flood plains in low country. Paleochannel fill and areas of flood-plain sediments were drilled, the lithology examined, and the sediments dated on the basis of their pollen content. No evidence was found for the existence before the Middle Ages of paleo- channels the size of the present River Elbe. Before the first measures were made to regulate the Elbe River, it was an anastomosing river system with numerous small branches. The lower parts of the flood-plain profiles are predominantly sand and the upper parts silty-clayey loam. With the construction of effective levees over the last several centuries, the flow velocity of the Elbe has increased considerably during high water periods and instead of the deposition of meadow loam, sand was deposited as natural levees. The main belt of sand dunes on the east bank of the Elbe overlies Preboreal to Boreal lake mud and is, therefore, of Holocene age.

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In NW of Portugal, the region between Esposende and Vila do Conde was established into a unique system called masseiras; masseiras are small fields that were created at the beginning of XX century by removing sand from dunes. Since the 80’s sand between closed masseiras has been removed giving way for larger fields, the “enlarged masseira with greenhouses”. This region is part of vulnerable zone nº1 (VZ1). Nowadays, the masseiras have almost disappeared; they had been replaced by “enlarged masseiras with plastic greenhouses” exploited by a new generation of growers. As water quality is an indicator of agriculture practices, 8 wells were selected and water samples were collected on four dates from September 2009 to May 2010. Laboratorial analysis was performed on nitrates and 28 pesticides. The results confirm that water in VZ1 is contaminated with nitrates (as it was expected) and also with pesticides. The water was contaminated in both dug wells and drilled wells all year round. Masseiras’ wells have more nitrates than greenhouses’ wells, probably due to poor agricultural practices used by growers who still employ high quantities of fertilizers and water. Pesticides detected in water samples include some that have been sprayed in the field and others that have not. Some forbidden substances were found. Our results confirm that, in VZ1, there is a diffusion contamination, which origin is unknown. In this communication, we put in picture the history of masseiras fields: how masseiras fields have been created and how they have disappeared; what trends exist in pest management strategies and the use of fertilizers, pesticides and water resources. These results reinforce the need to change the agricultural system in this region of traditional vegetable production.

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Recent studies concerning the landscape have investigated the most important activities that contribute for its modification and have tried to better understand the society through the marks left by its quotidian. It is understood that singular landscapes constitute the cultural patrimonies of the cities, once they are part of the daily life of the citizens and are present in their social representations. Some contemporary authors defend the preservation of the natural and urban landscape trying, specially, to keep its importance for the local population. Natal is a city where the ambient qualities are well defined and known by the beauty of the area where it is located. Situated just between a river and the sea, the city grew following its geographic characteristics. The Potengi River, the Atlantic Ocean and the vast dunes ecosystem represented natural limits to the urban expansion; at the same time they have favored the development of a landscape pattern marked by the dialectic between the natural elements and the human interventions. However, this relationship changed after the intensification of the high rising development process that took place since the 1960s. The urban legislation tried to preserve the features of the local landscape delimiting Areas for Controlling Building High , destined to protect the scenic value of some parts of the city. On the other hand, the civil construction sector has made constant pressure in sense to abolish or to modify this legal instrument, aiming profits that have increased, in the 1990s, because of the consumption and the qualification of the urban space for tourist activities. It is necessary the raising of new elements to stimulate the quarrel about the landscape preservation, the process of the urban space production and the best way for the legislation implementation. This work tries to raise elements about the subject at local level, in sense to use Natal City experience to contribute for the formulation of indicators to raise the question about the lack of measure for subjective values, for example the cultural and affective value of the landscape. The natural elements inserted in the urban profile, represent strong visual references and supply identity to the town; they are part of the collective imaginary and are detached in the social context of the city. Then, why the preservation of the landscape, that estimates the improvement in the quality of life, is not enough to justify the controlling building high already previewed as part of Natal City Legislation? These questions send us to the approach of the landscape, as a community patrimony, alerting that some of its significant esthetics attributes must be preserved as a legacy for the future generations

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Isolated carbonate platforms occur throughout the geologic record, from Archean to present. Although the respective roles of tectonics, sediment supply and sea-level changes in the stratigraphical architecture of these systems are relatively well constrained, the details of the nature and controls on the variability of sedimentological patterns between and within individual geomorphologic units on platforms have been barely investigated. This study aims at describing and comparing geomorphological and sedimentological features of surficial sediments and fossil reefs from three isolated carbonate platforms located in the SW Indian Ocean (Glorieuses, Juan de Nova and Europa). These carbonate platforms are relatively small and lack continuous reef margins, which have developed only on windward sides. Field observations, petrographic characterization and grain-size analyses are used to illustrate the spatial patterns of sediment accumulation on these platforms. The internal parts of both Glorieuses and Juan de Nova platforms are blanketed by sand dunes with medium to coarse sands with numerous reef pinnacles. Skeletal components including coral, green algae, and benthic foraminifera fragments prevail in these sediments. Europa platform exhibits a similar skeletal assemblage dominated by coral fragments, with the absence of wave-driven sedimentary bodies. Fossil reefs from the Last interglacial (125,000 years BP) occur on the three platforms. At Glorieuses, a succession of drowned terraces detected on seismic lines is interpreted as reflecting the last deglacial sea-level rise initiated 20,000 years ago. These findings highlight the high potential of these platforms to study past sea-level changes and the related reef response, which remain poorly documented in the SW Indian Ocean.

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As camarinhas ('Corema album' L. D. Don) são pequenos frutos selvagens que se desenvolvem em arbustos dunares ao longo das costas da Península Ibérica. Apesar de serem ainda pouco conhecidas, as camarinhas são pequenos frutos que podem pertencer ao vasto grupo dos frutos vermelhos, vulgarmente conhecidos pelos seus efeitos benéficos na saúde. Desta forma, neste estudo foram realizadas várias análises às camarinhas no que respeita a propriedades de natureza física e química e em particular a alguns compostos com efeitos bioativos. Com a realização deste trabalho pretendeu-se avaliar as propriedades físico-químicas das camarinhas, bem como dos compostos bioativos com potenciais benefícios para a saúde. Nesse sentido, as bagas de camarinha foram avaliadas quanto às suas propriedades físicas (dimensões, peso, cor e textura), propriedades químicas (humidade, acidez, ºBrix, fibra, açúcares totais, açúcares redutores e vitamina C) e propriedades fenólicas (compostos fenólicos totais, orto-difenóis, flavonóides, taninos e atividade antioxidante, por DPPH e ABTS), em diferentes extratos de amostras de polpas e de grainhas liofilizadas. Os primeiros extratos ainda foram submetidos a uma simulações das condições do trato digestivo, para avaliar a bioacessibilidade dos compostos fenólicos e da atividade antioxidante. Este trabalho teve ainda como objetivo conhecer a bioacessibilidade dos compostos fenólicos totais e da sua atividade antioxidante, através do método da simulação “in vitro” das diferentes etapas do trato gastrointestinal. No que diz respeito às propriedades físicas analisadas, as camarinhas frescas demonstraram uma altura média de 8,6 mm, um diâmetro médio de 9,4 mm e uma massa média de 0,7 g. Relativamente à caraterização da cor, estas apresentavam uma cor clara (L*=79,8). Quanto à textura apresentaram alguma elasticidade média (2,9 mm) e uma baixa dureza (1,9 N). Nas análises químicas as camarinhas revelaram ser compostas, maioritariamente, por água (87,9%), por açúcares totais e fibras. Para além disso, apresentavam um teor em sólidos solúveis totais de 6,3 ºBrix, uma acidez de 1,4 g ácido tartárico/100 g e um teor de vitamina C de 2,8 mg de ácido ascórbico/100 g.Na quantificação dos compostos fenólicos totais e flavonóides, os extratos de acetona:água das amostras de polpas de camarinha branca apresentaram os valores mais elevados, 1614,1 mg EAG/100 g e 143,7 mg EQ/100 g, respetivamente. Relativamente à quantificação dos orto-difenóis e dos taninos os extratos de metanol e de acetona:água das amostras de grainhas de camarinha branca registaram os valores de 23,4 mg EAG/100 g e 915,7 mg/100 g, respetivamente. Na atividade antioxidante por DPPH e ABTS os extratos de acetona:água das amostras de polpas de camarinha branca apresentaram, respetivamente, os valores de 40,1 µmol ET/g e de 79,6 µmol ET/g. Na avaliação da bioacessibilidade verificou-se que ocorreu uma maior percentagem de compostos fenólicos disponíveis para absorção e uma maior preservação da sua atividade antioxidante nos extratos das grainhas, comparativamente aos extratos das polpas. Com este estudo concluiu-se que as camarinhas são pequenos frutos portadores de um grande potencial em diversos compostos bioativos benéficos para a saúde dos consumidores.

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Presented are the results of research into the fluvio-aeolian sedimentary succession at the site of Postolin in the Żmigród Basin, southwest Poland. Based on lithofacies analysis, textural analysis, Thermoluminescence and Infrared-Optical Stimulated Luminescence dating and GIS analysis, three lithofacies units were recognised and their stratigraphic suc- cession identified: 1) the lower unit was deposited during the Pleni-Weichselian within a sand-bed braided river fun- ctioning under permafrost conditions within the central part of the alluvial fan; 2) the middle unit is the result of aeolian deposition and fluvial redeposition on the surface of the fan during long-term permafrost and progressive decrease of humidity of the climate at the turn of the Pleni- to the Late Weichselian; 3) the upper unit accumulated following the development of longitudinal dunes at the turn of the Late Weichselian to the Holocene; the development of dunes was interrupted twice by the form being stabilised by vegetation and soil development.