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Daily morphological changes determined by high-energy events on an embayed beach: a qualitative model

MARTINS, Cristina Celia; MAHIQUESH, Michel Michaelovitch de; DIAS, Joao Manuel Alveirinho
Fonte: JOHN WILEY & SONS LTD Publicador: JOHN WILEY & SONS LTD
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
37.13%
This paper examines the daily morphological responses of Sununga Beach, an embayed beach located on the south-eastern Brazilian coast, to storms in the South Atlantic Ocean. The main mechanisms and timing of beach erosion and accretion, the relationship between wave height and direction, and beach volume changes are considered, to establish a qualitative model for short-term embayed beach morphological changes. The methodology consisted of daily topographic surveys during the month of May in 2001, 2002, and 2003, using an RTK-GPS (real-time kinematics global positioning system). Weather and wave model results were used to correlate hydrodynamics and beach morphology. The results indicate that the morphodynamics of Sununga Beach are characterized by a process of beach rotation, which occurred more or less clearly during all three surveys. Unlike what has been commonly described in the literature for longer time intervals and alternations of fair and stormy weather, the beach rotation processes on Sununga Beach occurred under conditions of moderate-to-high wave energy change (wave heights greater than 2 m). An integrated evaluation of the behaviour of the meteorological aspects, together with beach morphology, enabled us to recognize that extra-tropical cyclones were the most important agent in remobilizing the beach planform...

Guiana dolphins (Sotalia guianensis) displaying beach hunting behavior in the Cananéia Estuary, Brazil: social context and conservation issues

Santos, Marcos César de Oliveira
Fonte: Universidade de São Paulo (USP), Instituto Oceanográfico Publicador: Universidade de São Paulo (USP), Instituto Oceanográfico
Tipo: Artigo de Revista Científica Formato: 143-152
Português
Relevância na Pesquisa
37.05%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Processo FAPESP: 01/05128-8; Com o intuito de detalhar o comportamento de procura e captura de alimento em praias ( beach hunting ) exibido por botos-cinza (Sotalia guianensis) no Estuário de Cananéia (EC) (25ºS, 48ºW), um estudo baseado na aplicação da técnica de foto-identificação foi conduzido de maio de 2000 a julho de 2003. Três plataformas de observação a foram escolhidas na principal entrada do mencionado estuário, onde os pesquisadores encontram uma oportunidade ímpar de observar os botos a uma pequena distância sem incomodá-los. As observações foram oportunísticas e desigualmente distribuídas ao longo do tempo e do espaço. Adicionadas às observações de identificação individual, uma balestra de 80lbs de pressão foi utilizada para coletar amostras de pele de oito indivíduos monitorados com vistas à determinação do sexo. em 67 dias de investigação, que renderam aproximadamente 80h de observações diretas dos botos, 4.102 fotografias foram tomadas, das quais 1.098 (26,8%) foram consideradas úteis para o propósito de identificação individual. Um total de 103 grupos foi observado (3,7 ± 2,6 indivíduos), variando entre botos solitários e 15 indivíduos. Pares de fêmeas e filhotes foram observados em 92...

Interannual sub-aerial beach variability along a sector of the Tróia- Sines embayed coast

Albardeiro, L.; Gama, C.; Marques da Silva, José Rafael; Baptista, P.
Fonte: Universidade de Évora Publicador: Universidade de Évora
Tipo: Aula
Português
Relevância na Pesquisa
37.16%
The comprehension of sub-aerial beach variability of sandy beaches is essential to describe and predict his behaviour after extreme events (e.g. storms). Around the world coastline beach monitoring plans are established in order to characterize the main morphodynamic changes at different spatial and temporal scales. Within this scope, four field surveys (19th to 28th May 2009; 30th October to 10th November 2009, 21th to 30th May 2010 and 14l to 21 April 2011), using a new coastal survey system named INSHORE system(Differential Global Positioning System) [1], were conducted along the Tróia-Sines embayed beach (INSHORE project -PTDC/AMB/73169/2006). The interannual variability of the sub-aerial beach topography along the Tróia-Sines embayed coast for the first three field surveys were analysed considering the DEM (Digital Elevation Model) analysis regarding the: alongshore coastline configuration; subaerial beach width; beach profile configuration and volumetric changes. The results points to the definition of eight main coastline sectors very similar to the results previously described by [2]. Although a general north-south increasing beach width trend can be observed, [3] one of these main sectors, Sector 6, presents a significant variation of the beach width and beach profile configuration. This sector was selected to describe the morphodynamic pattern responsible for the sediment accommodation (beach width...

Beachface and berm morphodynamics on a steep beach: Melides beach, Southwest Portugal.

Gama, Cristina; Baptista, Paulo; Marques da Silva, Rafael; Pinheiro, Isabel
Fonte: Universidade de Évora Publicador: Universidade de Évora
Tipo: Aula
Português
Relevância na Pesquisa
37.11%
The Melides beach, a sector of the Tróia-Sines Embayed Coast with 2.5km long, corresponds to a steep beach exposed to high-wave energy, with rapid erosion and accretion cycles related to winter storm incidence. The alongshore and cross-shore beach volume and width variability of the Melides beach were studied in detail using a survey methodology based on DGPS (Global Positioning System in Differential mode) and a Geographical Information System application. This survey methodology is based on a network of longitudinal and transversal DGPS profiles established on all subaerial beach. The three-dimension approach provided by DGPS methodology allowed a more robust description of the mean subaerial beach profile variations than bi-dimension studies provided by classical geodetic studies. The high match between alongshore patterns of the profile volumes variability before and after storm incidence in the Melides beach, suggests that the main factor that controls beach morphodynamics is the cross-shore sediment transport The seasonal cycle of erosion and accretion of the Melides beach seems to be triggered by variations in the wave incident energy (storm events). The incidence of a storm on January of 2008 led to significant shoreline shift with beachface retreat (24m) as well as...

Short-term evolution of a reflective beach sector in front of a coastal lagoon (Southwest).Portuguese coast)

Gama, Cristina; Albardeiro, Luís; Jacob, José; Pinheiro, Isabel
Fonte: Universidade de Évora Publicador: Universidade de Évora
Tipo: Aula
Português
Relevância na Pesquisa
37.1%
The subaerial beache act as detritical barriers in the opening and closing of lagoons located in sandy coastal ares. The study of beach morphodynamics, considering the evolution of the beachface and the berm, in these cases is critical to coastal management. The studied area located in an embayed sandy coastline at the Portuguese Southwest Atlantic Coast, is a 308m long subaerial, coarse to very coarse, sandy beach adjacent to the Melides lagoon entrance. In order to characterize the morphodynamics of the study area under the effects of storms (pre and post-storm) and tides (spring and neap tides) during a period of one year (April 2010 to April 2011), 26 field surveys were conducted. A survey grid with an alongshore lenght of 308m and a widht of 14-40m defined between the lower limit of the beachface and the backshore limit (entrance of the coastal lagoon or frontal dune) was used. We performed 12 cross-shore profiles 40m apart from each other. The alongshore profiles describes the main topographic variations (e.g. top of the beachface, berms elevation, beach cusps definition). Horizontal and vertical positioning was provided by Real-Time Kinematics (RTK) GPS. The results obtained allowed to develop high resolution Digital Elevation Models (DEM) using the ArcGIS software. DEM models were use to describe beach morphologicnd changes. The nearshore wave characteristics were described by the SWAN wave model considering as boundary conditions the wave data recorded at the Sines wave rider buoy. The run-up levels were calculated using the wave parameters and the beachface slope (0.12 to 0.18). During the study period were documented two episodes of opening and closing of the Melides lagoon due to storms effect...

Short-term evolution of a reflective beach sector in front of a coastal lagoon (Southwest Portuguese coast)

Gama, Cristina; Albardeiro, Luís; Jacob, José; Pinheiro, Isabel
Fonte: 32nd International Geographical Congress Publicador: 32nd International Geographical Congress
Tipo: Aula
Português
Relevância na Pesquisa
37.05%
Several coastal lagoon entrances are controlled by the contiguous subaerial beach that works as a detrital barrier. Hence the importance of characterizing the adjacent beach morphodynamics regarding the beachface and berm reconstruction for coastal management proposals. The studied area, a subaerial beach sector of 308 m, located in front of the Melides coastal lagoon, is placed in an embayed sandy coastline at the Portuguese Southwest Atlantic Coast. During one year (April 2010 to April 2011), 26 field surveys were conducted in order to describe the evolution of this subaerial beach sector. The periodicity of the campaigns was defined in order to characterize the effects of storms (pre and post-storm) and tides (spring and neap tides), on subaerial beach morphodynamics adjacent to the lagoon entrance. A survey grid with an alongshore length of 308m and a width defined between the lower limit of the beachface and the backshore limit (entrance of the coastal lagoon or frontal dune) was used. This grid considered 12 cross-shore profiles apart by 40 m. The alongshore profiles describes the main topographic variations (e.g. top of the beachface, berms elevation, beach cups definition). Horizontal and vertical positioning was provided by Real-Time Kinematic (RTK) GPS. The results allowed the construction of high resolution Digital Elevation Model (DEM) of the studied area. This data were used to describe in detail the beach morphologic changes using the ArcGIS software. The superficial beach sediments were also collected pointing to the predominance of coarse to very coarse sand. The nearshore wave characteristics was described by the SWAN wave model considering as boundary conditions wave data recorded at the Sines wave rider buoy. The run-up levels were calculated considering the wave parameters and the beachface slope (0.12 to 0.18...

Routine screening of harmful microorganisms in beach sands: implications to public health

Sabino, Raquel; Rodrigues, R.; Costa, I.; Carneiro, C.; Cunha, M.; Duarte, A.; Faria, N.; Ferreira, F. C.; Gargaté, M. J.; Júlio, C.; Martins, M. L.; Nevers, M. B.; Oleastro, M.; Solo-Gabriele, H.; Veríssimo, C.; Viegas, Carla; Whitman, R. L.; Brandão
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em /02/2014 Português
Relevância na Pesquisa
37.07%
Beaches worldwide provide recreational opportunities to hundreds of millions of people and serve as important components of coastal economies. Beach water is often monitored for microbiological quality to detect the presence of indicators of human sewage contamination so as to prevent public health outbreaks associated with water contact. However, growing evidence suggests that beach sand can harbor microbes harmful to human health, often in concentrations greater than the beach water. Currently, there are no standards for monitoring, sampling, analyzing, or managing beach sand quality. In addition to indicator microbes, growing evidence has identified pathogenic bacteria, viruses, and fungi in a variety of beach sands worldwide. The public health threat associated with these populations through direct and indirect contact is unknown because so little research has been conducted relating to health outcomes associated with sand quality. In this manuscript, we present the consensus findings of a workshop of experts convened in Lisbon, Portugal to discuss the current state of knowledge on beach sand microbiological quality and to develop suggestions for standardizing the evaluation of sand at coastal beaches. The expert group at the "Microareias 2012" workshop recommends that 1) beach sand should be screened for a variety of pathogens harmful to human health...

Provenance, transport and composition of Dendê Coast beach sands in Bahia, central coast of Brazil

Rebouças,Renata Cardia; Dominguez,José Maria Landim; Bittencourt,Abílio Carlos da Silva Pinto
Fonte: Universidade de São Paulo, Instituto Oceanográfico Publicador: Universidade de São Paulo, Instituto Oceanográfico
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2011 Português
Relevância na Pesquisa
37.05%
The great physiographic diversity of the Dendê Coast favors the production of different beach sediment types, including bioclastic components. In this study 74 beach samples collected at 2 km intervals were used to evaluate beach sediment composition. For each sample, 300 grains were identified for each grain size class coarser than 0.125 mm, using a binocular microscope. The beach sediments of the Dendê Coast are essentially siliciclastic (80-100%). Quartz is the major component (70-100%). Only at the Tinharé and Boipeba islands bioclasts are major components of beach sands reaching up to 80-100%. These sediments are made up essentially of fragments of Halimeda, reaching percentages up to 70%. Coralline algae and mollusks also contribute significantly to these sediments (up to 30%). The results obtained show that the spatial distribution of the bioclastic components provide important information on the environmental conditions present at the shoreline (energy levels, availability of hard substrates and protected areas, pattern of sediment dispersion) and on the sediment sources as well. The composition of the beach sediments on the Dendê Coast reflects the present day environmental conditions and show that these sediments do not experience significant lateral transport. This situation is favored by an impeded longshore transport that characterizes most of the region. Although...

Frequency beach profile monitoring: implications in beach safety at Cassino beach, southern Brazil

Pereira, Pedro de Souza; Calliari, Lauro Julio; L??lis, Renato Jos?? Furigo
Fonte: Universidade Federal do Rio Grande Publicador: Universidade Federal do Rio Grande
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
37.05%
During the summer of 2002 and 2003, daily monitoring of beach profiles were conducted at Cassino Beach, a highly dissipative beach in southern Brazil in order to verify changes in the dynamic inner and outer bar systems which could provide additional information to beach safety programs. Distances and depths of the troughs from the water line oscillated between 55m and 0.89m respectively for the first trough, to 160m, and 1.78mfor the third trough.At low wave energy conditions, average migration rates of the first and second bar reached 4.8 m/day. The total number of accidents, in the summer 2002, were equally associated with both, dissipative and the intermediate morphodynamic states, however the accidents in the summer 2003 occurred only in the intermediate type. The presence of a deep trough imprint in the intermediate beach type, a higher hazardous morphology level. The 2003 campaign documented stable profiles, showing a low mobility and constant morphology with the same beach type, with a deep trough that reached the depth of 2.4m at a distance of 96m from the water line. It is believed that this low mobility was caused by the presence of mud bottoms at the nearshore zone.

Beach memory

Turki, Imen; Medina Santamaría, Raul; González Rodríguez, Ernesto Mauricio
Fonte: Coastal Engineering Research Council Publicador: Coastal Engineering Research Council
Tipo: info:eu-repo/semantics/article; publishedVersion
Português
Relevância na Pesquisa
37.13%
A new concept of beach memory is investigated in this research. Using a Beach Evolution Model developed for beach rotation, we define a function of beach memory able to describe the weight of the preceding wave conditions and their contribution in the current beach response. The time beach memory time is also defined as the period of time required for the beach memory function to be dissipated in the previous time to negligible values. The Beach Memory Function and the Beach Memory Time can be used to determine the influence of the preceding energy in the current coastal changes. Both new concepts were applied to quantify the Weighted Energy Flux Direction required for the beach planform to be estimated based on the parabolic approximations. Modeled results reproduce successfully observed planform positions.

Proyecto de los diques y espigones propuestos para la estabilización de la playa de La Magdalena, Santander, Cantabria; Design of the breakwaters proposed for the regeneration of the Magdalena beach, Santander, Cantabria

Torralbo Asla, Julia
Fonte: Universidade de Cantabria Publicador: Universidade de Cantabria
Tipo: Trabalho de Conclusão de Curso
Português
Relevância na Pesquisa
37.16%
RESUMEN: PLANTEAMIENTO DEL PROBLEMA En el término municipal de Santander se encuentran numerosas playas: Los Peligros, La Magdalena, Los Bikinis, El Camello, La Concha, El Sardinero, Los Molinucos, Mataleñas, El Bocal, La Maruca y La Virgen del Mar. De todo este conjunto de playas es, sin duda, el sistema de playas Peligros-Magdalena-Bikinis uno de los más representativos del municipio, tanto por su ubicación en plena ciudad, próximo al núcleo habitacional, como por su situación en la parte noroeste de la Bahía de Santander, encajada entre La Península de la Magdalena (al este) y el Promontorio de San Martín (al oeste). La Playa de Los Peligros se encuentra limitada por el Muelle del Promontorio de San Martín al oeste y por la playa de La Magdalena al este. La Playa de La Magdalena, se sitúa entre la playa de Los Peligros y Los Bikinis. Por último, la playa de Los Bikinis, la más oriental del sistema linda al este con la Península de la Magdalena y se encuentra dividida por un espigón, el Espigón de Bikinis. Este sistema de playas viene sufriendo a lo largo de las últimas décadas una erosión, en la zona adyacente al Balneario de La Magdalena, con la consiguiente reducción de la playa seca y afección a elementos colindantes (descalce de muros e instalaciones)...

Proyecto de los diques y espigones propuestos para la estabilización de la playa de La Magdalena, Santander, Cantabria; Design of the breakwaters proposed for the regeneration of the Magdalena beach, Santander, Cantabria

Torralbo Asla, Julia
Fonte: Universidade de Cantabria Publicador: Universidade de Cantabria
Tipo: Trabalho de Conclusão de Curso
Português
Relevância na Pesquisa
37.16%
RESUMEN: PLANTEAMIENTO DEL PROBLEMA En el término municipal de Santander se encuentran numerosas playas: Los Peligros, La Magdalena, Los Bikinis, El Camello, La Concha, El Sardinero, Los Molinucos, Mataleñas, El Bocal, La Maruca y La Virgen del Mar. De todo este conjunto de playas es, sin duda, el sistema de playas Peligros-Magdalena-Bikinis uno de los más representativos del municipio, tanto por su ubicación en plena ciudad, próximo al núcleo habitacional, como por su situación en la parte noroeste de la Bahía de Santander, encajada entre La Península de la Magdalena (al este) y el Promontorio de San Martín (al oeste). La Playa de Los Peligros se encuentra limitada por el Muelle del Promontorio de San Martín al oeste y por la playa de La Magdalena al este. La Playa de La Magdalena, se sitúa entre la playa de Los Peligros y Los Bikinis. Por último, la playa de Los Bikinis, la más oriental del sistema linda al este con la Península de la Magdalena y se encuentra dividida por un espigón, el Espigón de Bikinis. Este sistema de playas viene sufriendo a lo largo de las últimas décadas una erosión, en la zona adyacente al Balneario de La Magdalena, con la consiguiente reducción de la playa seca y afección a elementos colindantes (descalce de muros e instalaciones)...

Guiana dolphins (Sotalia guianensis) displaying beach hunting behavior in the Cananéia Estuary, Brazil: social context and conservation issues

Santos, Marcos César de Oliveira
Fonte: Universidade de São Paulo. Instituto Oceanográfico Publicador: Universidade de São Paulo. Instituto Oceanográfico
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; Formato: application/pdf
Publicado em 01/06/2010 Português
Relevância na Pesquisa
37.05%
Com o intuito de detalhar o comportamento de procura e captura de alimento em praias (“beach hunting”) exibido por botos-cinza (Sotalia guianensis) no Estuário de Cananéia (EC) (25ºS, 48ºW), um estudo baseado na aplicação da técnica de foto-identificação foi conduzido de maio de 2000 a julho de 2003. Três plataformas de observação a foram escolhidas na principal entrada do mencionado estuário, onde os pesquisadores encontram uma oportunidade ímpar de observar os botos a uma pequena distância sem incomodá-los. As observações foram oportunísticas e desigualmente distribuídas ao longo do tempo e do espaço. Adicionadas às observações de identificação individual, uma balestra de 80lbs de pressão foi utilizada para coletar amostras de pele de oito indivíduos monitorados com vistas à determinação do sexo. Em 67 dias de investigação, que renderam aproximadamente 80h de observações diretas dos botos, 4.102 fotografias foram tomadas, das quais 1.098 (26,8%) foram consideradas úteis para o propósito de identificação individual. Um total de 103 grupos foi observado (3,7 ± 2,6 indivíduos), variando entre botos solitários e 15 indivíduos. Pares de fêmeas e filhotes foram observados em 92,4% dos grupos investigados. Apresenta-se a primeira notificação de intervalo de nascimento de um filhote para o EC: aproximadamente 3 anos e 9 meses. De 40 indivíduos identificados ao menos uma vez...

Provenance, transport and composition of Dendê Coast beach sands in Bahia, central coast of Brazil

Rebouças, Renata Cardia; Dominguez, José Maria Landim; Bittencourt, Abílio Carlos da Silva Pinto
Fonte: Universidade de São Paulo. Instituto Oceanográfico Publicador: Universidade de São Paulo. Instituto Oceanográfico
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Formato: application/pdf
Publicado em 01/12/2011 Português
Relevância na Pesquisa
37.05%
The great physiographic diversity of the Dendê Coast favors the production of different beach sediment types, including bioclastic components. In this study 74 beach samples collected at 2 km intervals were used to evaluate beach sediment composition. For each sample, 300 grains were identified for each grain size class coarser than 0.125 mm, using a binocular microscope. The beach sediments of the Dendê Coast are essentially siliciclastic (80-100%). Quartz is the major component (70-100%). Only at the Tinharé and Boipeba islands bioclasts are major components of beach sands reaching up to 80-100%. These sediments are made up essentially of fragments of Halimeda, reaching percentages up to 70%. Coralline algae and mollusks also contribute significantly to these sediments (up to 30%). The results obtained show that the spatial distribution of the bioclastic components provide important information on the environmental conditions present at the shoreline (energy levels, availability of hard substrates and protected areas, pattern of sediment dispersion) and on the sediment sources as well. The composition of the beach sediments on the Dendê Coast reflects the present day environmental conditions and show that these sediments do not experience significant lateral transport. This situation is favored by an impeded longshore transport that characterizes most of the region. Although...

The Economic Influence of Beach Nourishment on the Local Real Estate Market in Brunswick County, North Carolina

Zhong, Bo
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Masters' project Formato: 470016 bytes; application/msword
Português
Relevância na Pesquisa
37.09%
Global climate change causes sea level rise and storm pattern changes, potentially worsening shoreline erosion. Growing risks of inundation and storm damage confronts coastal development. As an active countermeasure for years, beach nourishment alleviates such threat to local properties. Previous research has analyzed the dynamics of beach system with corresponding management strategies, the cost issue of beach nourishment, and the role of beach in a hedonic property model framework employing principles of renewable resource economics. Statistical analysis of local real estate market provides evidence on the effectiveness of beach nourishment in protecting local properties. By incorporating properties’ distance to shoreline as one independent variable and beach nourishment condition as dummy variable, the regression of properties’ sale price against housing characteristics suggests how beach nourishment alters the market trend underlying residential property transactions. As for Brunswick County, North Carolina, in this study, the regression results show that before beach nourishment, properties closer to shoreline were generally less favored, while after beach nourishment, shorter distance to sea becomes preferred. Because of limited sample size and thus no further detailed stratifying the properties according to the distance to shoreline...

An Assessment of the Effectiveness and Usage of the Surfrider Foundation Annual State of the Beach Report

Bain, John
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Masters' project Formato: 2508944 bytes; application/pdf
Português
Relevância na Pesquisa
37.07%
Every year since 2000, the Surfrider Foundation has released the State of the Beach Report. This annual report uses a suite of coastal health indicators to rate coastal state management information availability and status. After eight years, the Surfrider Foundation wanted to know how well the State of the Beach Report was measuring coastal health and to what extent it was utilized in creating coastal policy. I used three separate metrics to assess the State of the Beach Report. First, using the Handbook for measuring the progress and outcomes of Integrated Coastal and Ocean Management (UNESCO, 2006), I created a hierarchy of those many aspects of beach health of interest to the Surfrider Foundation. By coding the various indicators used in the State of the Beach Report I was able to determine that the report directly addressed 32 of the 34 subcategories and thus is an appropriate measure of coastal health. Secondly, I analyzed data from each of the previous eight State of the Beach Reports to determine where changes in indicator grades signified a trend. Once these trends were identified I identified the cause of each change. The majority of these changes were the result of states increasing the amount and availability of information related to coastal zone issues. The BEACH Act...

Modeling hydrodynamics and sediment transport in an inlet-beach system

Keshtpoor, Mohammad
Fonte: University of Delaware Publicador: University of Delaware
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
37.11%
Puleo, Jack A.; Shi, Fengyan; Indian River Inlet (IRI), DE, USA, is located at roughly the midpoint of ~ 40 km Atlantic coast of Delaware and is the major waterway that connects the Atlantic Ocean to two Delaware inland bays. Twin jetties constructed in late 1930s to keep the inlet from filling also interrupt the alongshore sediment transport. The direct impact of jetty construction has been updrift beach accretion and downdrift beach erosion. In 1990, the U.S. Army Corps of Engineers (USACE) constructed a sand bypassing system to mitigate the downdrift beach erosion by transferring sand slurry from the updrift to downdrift side of the inlet. In an effort to investigate the impact of the bypassing system on downdrift beach, statistical analyses techniques are applied on beach profile data collected from 1985 until 2008 to address two questions. First, did the bypassing system fulfill the beach nourishment goals? If so, how much material is enough to be bypassed to protect the downdrift beach? Empirical Orthogonal Eigenfunction analysis was applied to investigate the temporal and spatial dependency of the downdrift beach on bypassing volumes. The downdrift beach has eroded severely since 2009, even though the bypassed volumes have exceeded the design values. A two dimensional (2D) depth averaged numerical model was used to shed light on nearshore hydrodynamic and morphodynamic patterns near the inlet. The major goal is to estimate the sediment transport rate variability under the effect of dominant directional waves to determine the important processes for downdrift beach erosion. In addition to downdrift beach erosion...

Granulometric aspects of the siliciclastic sediments of the beach - foredune system of Sombrio sheet, southern Santa Catarina State, Brazil; Aspectos granulométricos dos sedimentos siliciclásticos do sistema praia - duna frontal da folha Sombrio, sul do estado de Santa Catarina, Brasil

de Oliveira, Ulisses Rocha; FURG
Fonte: Editora da UFSC Publicador: Editora da UFSC
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Formato: application/pdf
Publicado em 01/01/2007 Português
Relevância na Pesquisa
37.1%
This paper shows some granulometric characteristics of the siliciclastics sediments referent to beach - foredune system of Sombrio sheet, southern Santa Catarina State, Brazil, and the morphologic and hydrodynamic characteristics associated. Along of 24 km of beach it shows homogeneity in the main characteristics. Among these detach fine sands, quartzose, well sorted and positive asymmetry, even in the beach or as in the foredune. Some heterogeneous characteristics were observed in the granulometry, morphology and hydrodynamic of this beach, as: one modal frequency in fraction 2,5 phi in the beach and in fractions 2,5 phi and 3 phi in the foredune; variations in the beach width and distribution of the washouts. By across to the observation of aerial photography’s and measures obtained in loco, the beach may be classify like a dissipative beach, with fine sands, low beach face slope and multiple bars, dominated by high wave energy. The characteristics of the beach - foredune system of Sombrio sheet, with successive bars and thoughts and wave breakers, washouts in direction to the beach and fine sands, well sorted, show strongly influenced by Holocene progradant barriers adjacent.; Neste trabalho são apresentadas as características granulométricas dos sedimentos siliciclásticos do sistema praia-duna frontal referente à área da folha Sombrio...

Beach dynamics and nest distribution of the leatherback turtle (Dermochelys coriacea )at Grande Riviere Beach,Trinidad &Tobago

Lee Lum,Lori
Fonte: Revista de Biología Tropical Publicador: Revista de Biología Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/05/2005 Português
Relevância na Pesquisa
37.07%
Grande Riviere Beach in Trinidad and Tobago is an important nesting site in the Caribbean for the Critically Endangered leatherback sea turtle,Dermochelys coriacea .Community members were concerned that beach erosion and seasonal river flooding were destroying many of the nests deposited annually and thought that a hatchery was a possible solution.Over the 2001 turtle nesting season,the Institute of Marine Affairs (IMA) assessed the spatial and temporal distribution of nests using the Global Positioning System recorded to reference points,and beach dynamics using permanent bench mark profile stations,to determine areas of high risk and more stable areas for nesting.A total of 1449 leatherback nests were positioned.It was evident that at the start of the season in March,the majority of leatherback nests were deposited at the eastern section of the beach. After May,there was a continuing westward shift in nest distribution as the season progressed until August and beach erosion in the eastern section became predominant.The backshore remained relatively stable along the entire beach throughout the nesting season,and erosion was predominant in the foreshore at the eastern section of the beach,from the middle to the end of the season.Similar trends in accretion and erosion were observed in 2000.River flooding did not occur during the study period or in the previous year.With both high risk and more stable regions for turtle nesting available at Grande Riviere Beach...

Putting beach slope prediction into perspective

Jewell,R.J.
Fonte: Journal of the Southern African Institute of Mining and Metallurgy Publicador: Journal of the Southern African Institute of Mining and Metallurgy
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2012 Português
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The storage capacity of any given tailings storage facility (TSF) is a function of the volume available for the tailings, for which the geometry of the final upper surface of the tailings is most important. One of the advantages that can be obtained from thickening tailings prior to discharge is that the tailings can be stacked at a steeper beach angle than is obtainable with conventional low-density slurries. However, there is at present no universally accepted method available for the accurate prediction of tailings beach slopes. This paper examines the current situation with the objective of putting the quest for a method for the accurate prediction of beach slopes into perspective. The paper references published reviews of the best-known beach slope prediction methods. However, there do not appear to be any independently verified projects or published references to projects on which a Class A prediction has been validated for any of these approaches, and in those instances where projects have been implemented correlation of actual with predicted slopes has been poor - often due to differences between the properties of the tailings assumed in the design and those actually achieved in the field. The author also concludes that flume-scale testing cannot be taken as a reliable indicator of full-scale performance...