Navegando por Autor "SOUZA FILHO, Pedro Walfir Martins e"

Agora exibindo 1 - 12 de 12

Acesso aberto (Open Access)
Análise faciológica e estratigráfica da planície costeira de Soure (margem leste da ilha de Marajó-PA), no trecho compreendido entre o canal do Cajuúna e o estuário Paracauari
(Instituto Nacional de Pesquisas da Amazônia, 2007-06) FRANÇA, Carmena Ferreira de; SOUZA FILHO, Pedro Walfir Martins e; EL-ROBRINI, Maâmar
Soures's coastal plain, eastern Marajó island (Pará), is formed by muddy and sandy deposits, low gradient areas submitted to tidal and wave processes. The morphological features are tidal flats, estuaries, tidal channels and barrier-beach ridges . The faciological and stratigraphical analysis of six vibra-core with medium deph of four meters and from outcrops allowed a caracterization of depositional environments, temporal sequence and spacial corelation, the elaboration of stratigraphical seccions and column. Were identified five facies associations: (1) tidal flat facies, (2) mangrove facies, (3) tidal channel bar facies, (4) beach facies and (5) dune facies. The sedimentary history of the Soure coastal plain is represented by two stratigraphical successions: (1) progradational succession (tidal flat, mangrove and channel bar facies association) and (2) retrogradational succession (beach and dune facies association). These successions are related to a expansion phase of tidal flats and mangroves with progradation of the coastline (Middle/Late Holocene) and a posterior retrogradation phase with landward migration of the shoreline (Late Holocene). The depositional history of the Soure coastal plain is related to the holocenic evolution model of the northeast coastal plains of Pará.
Acesso aberto (Open Access)
Avaliação de áreas deposicionais e erosivas em cabos lamosos da zona costeira amazônica através da análise multitemporal de imagens de sensores remotos
(2012) BATISTA, Edmilson das Mercês; SOUZA FILHO, Pedro Walfir Martins e; SILVEIRA, Odete Fátima Machado da
The Cassiporé and Orange mudcapes in the Northern of Brazil constitute a dynamic environment influenced by the Amazon river, where the shoreline changes are subjected to severe processes of progradation and erosion. Optical and microwaves remote sensed images were acquired from 1980 to 2003, and analyzed in a Geographic Information System (GIS), allowing the identification and quantification of prograding and retrograding areas along the shoreline. During this period, the largest erosion rates had occurred next to the Cassiporé Cape, with mean retreat of 27.5 m of linear distance and erosion of 1.37 km² of mangrove area per year. On the other hand, the largest rates of sediment deposition had occurred in the Orange Cape, where the coastal prograded 24.6 m per year, adding 55.86 km² of mangrove area to shoreline in the last 23 years. The progradation mechanisms have determined an accretion in the mangrove vegetation of 50.8% throughout the last three decades. A sedimentary balance carried out in the study area showed that constructive processes (61.3%) are dominant over erosive processes (38.7%).
Acesso aberto (Open Access)
Avaliação e aplicação de dados de sensores remotos no estudo de ambientes costeiros tropicais úmidos, Bragança, norte do Brasil
(Universidade Federal do Pará, 2000-11-17) SOUZA FILHO, Pedro Walfir Martins e; EL-ROBRINI, Maâmar; http://lattes.cnpq.br/5707365981163429
The study site is situated in the Cretaceous Bragança-Viseu coastal basin. The holocenic evolution of this area is marked by muddy progradation over a submerging coast, where is developed one of the most mangrove system of the world, with almost 6,000 km2. This research has showed that orbital remote sensing data can provide excellent geologic and coastal land use information. The SAR RADARSAT-1 imageries represent a powerful tool to understand the coastal processes in the wet tropical environments, mainly in the mangrove coasts. This fact is related to microwave radiation can be interpreted for Amazon coastal zone mapping and monitoring, because SAR image constitutes in the unique source of data with all-weather remote sensing capability, in response to difficulty to get optical images in the Amazon, due to all-time cloud cover. Landsat TM imageries are excellent data sources to integration with RADARSAT-1. They present a good performance in coastal environments discrimination. The remote sensing data integration allow a synoptic view of the area and provide geobotanic (relation between coastal environment and vegetation) and multitemporal information. In addition to integrated data, geographic information system (GIS) combines different data sets and simultaneously interprets the spatial and temporal relationship between various coastal environments. This way, GIS allows for a more comprehensive, accurate and easier interpretation of a geomorphologic mapping under an organizational philosophy to control data towards use the information to coastal zone management. The application of remote sensing data in the tropical coastal studies was used in different approaches. In relation to spatial and temporal variability of the shoreline, this study has revealed that during the Holocene, the coastal plain is marked by a muddy progradation. However, from the analysis of the remote sensing images were possible investigate the shoreline variability under long (1972-1998) and short (1985-1988, 1988-1990, 1990-1991) term, which is characterized by shoreline retreat, probably due to climatic changes, such as El-Niño and La-Niña events. These climatic events control the rainfall along the coastal zone, where severe erosional period (1985- 1988) are coupled with high precipitation rate (> 4,000 mm/yr.). From the point of view of the spatial analysis of the coastal changes, the mangroves constitutes one of the most environments to be analyzed by remote sensing images, as in the electro-optical spectrum due to their high reflectance in the infrared, as in the microwave due to their rough surface responsible for high backscattering. Therefore, mangroves have showed to be an excellent geologic indicator to detect and to quantify short and long-term morphological coastal changes. To conclude, remote sensing data integration, GIS and auxiliary fieldwork data present a fundamental role to the integrated coastal zone management, environmental risk assessment, local characterization of the study sites, base maps upgrading and information dissemination for public consultation, which are all significant factors in this decision-making process.
Acesso aberto (Open Access)
Costa de manguezais de macromaré da Amazônia: cenários morfológicos, mapeamento e quantificação de áreas usando dados de sensores remotos
(2005-12) SOUZA FILHO, Pedro Walfir Martins e
De acordo com o Atlas de Manguezais, este ecossistema representa 8% de toda a linha de costa do planeta e um quarto da linha de costa da zona tropical, perfazendo um total de 181.077 km2. Este trabalho objetiva quantificar a extensão dos manguezais de macromaré da costa nordeste do Pará e noroeste do Maranhão, aqui denominada de Costa de Manguezais de Macromaré da Amazônia (CMMA). O reconhecimento das áreas de manguezais e sua quantificação foram realizados a partir da utilização de imagens Landsat-7 ETM+, adquiridas em 1999 e 2000 e de um sistema de informações geográficas (SIG). A integração dos dados de sensores remotos, dados geológicos e oceanográficos permitiu o reconhecimento de cinco setores geomorfológicos, que abrangem uma superfície total de 7.591 km2 de manguezais. Esta área representa a maior faixa de manguezais contínuos do planeta e corresponde a 56,6% dos manguezais do Brasil. Medidas prioritárias de conservação dos manguezais da Amazônia devem ser tomadas e pesquisas que busquem a melhor compreensão deste complexo e importante ecossistema devem ser financiadas e desenvolvidas.
Acesso aberto (Open Access)
Environmental sensitivity index (ESI) mapping of oil spill in the amazon coastal zone: the PIATAM Mar project
(2009) SOUZA FILHO, Pedro Walfir Martins e; PROST, Maria Thereza Ribeiro da Costa; MIRANDA, Fernando Pellon de; SALES, Maria Emília Cruz; BORGES, Heloisa Vargas; COSTA, Francisco Ribeiro da; ALMEIDA, Edson Faria de; NASCIMENTO JUNIOR, Wilson da Rocha
The importance of environmental monitoring is clear from the many oil spills that have occurred over the past three decades. This has encouraged both companies and the public sector involved in the prevention and response to these accidents to develop efficient procedures to minimize the damage caused by accidents involving oil spill. This study reviews the history of oil spill accidents in Brazil and examines how these events have contributed to the development of technological research through partnerships involving oil companies, government, universities and research institutes, with the emphasis on the Amazon coastal zone. As a result, environmental sensitivity indexes (ESIs) for oil spill have been developed specifically for the Amazon coast, where fluvial and marine processes take place in the estuary of the world's largest river system. Perspectives on research and emergency response procedures are presented, with the primary objective of conserving the social-environmental diversity of the planet's most important tropical region.
Acesso aberto (Open Access)
Fusão de dados multisensor para a identificação e o mapeamento de ambientes flúvio-estuarinos da Amazônia
(2009) GONÇALVES, Fabrício Dias; SOUZA FILHO, Pedro Walfir Martins e; PARADELLA, Waldir Renato; MIRANDA, Fernando Pellon de
Multisensor data fusion has been widely used in response to complementary nature of many data sets. This paper compares the results of four different data fusion methods used to merge Landsat-7 ETM+ and RADARSAT-1 Wide 1 data. The comparison was based on spectral characteristics of images using statistical and visual analyses of generated products. Four methods were used in the Landsat-7 ETM+ and RADARSAT-1 W1 data fusion: i) The best three bands combination(Landsat-7) based OIF (Optimum Index Factor) selection were merged with RADARSAT-1 data; ii) Decorrelation stretch was applied in the three bands (Landsat-7) selected by OIF and merged with RADARSAT-1 image; iii) PCA (Principal Component Analysis) to six reflective ETM+ bands (1, 2, 3, 4, 5 and 7) and posterior fusion of the three first Principal Components (PC1, PC2, PC3) with SAR; iv) A new approach SPC-SAR (Selective Principal Component - Synthetic Aperture Radar). The SPC-SAR product presented the best performance in the identification of coastal features and allowed the most effective enhancement of the different environments.
Acesso aberto (Open Access)
Holocene history of a lake filling and vegetation dynamics of the Serra Sul dos Carajás, southeast Amazonia
(Academia Brasileira de Ciências, 2017-08-24) GUIMARÃES, José Tasso Felix; SAHOO, Prafulla Kumar; SOUZA FILHO, Pedro Walfir Martins e; FIGUEIREDO, Mariana Maha Jana Costa de; REIS, Luiza Santos; RODRIGUES, Tarcísio Magevski; SILVA, Marcio da Silva
Down-core changes in sedimentary facies, elemental geochemistry, pollen, spore, δ13C, δ15N and radiocarbon records from a filled lake, named R4, of the Serra Sul dos Carajás were used to study the relationship between the paleomorphological and paleoecological processes and their significance for Holocene paleoclimatology of the southeast Amazonia. The sediment deposition of the R4 lake started around 9500 cal yr BP. Increase of detrital components from 9500 to 7000 cal yr BP suggests high weathering of surrounding catchment rocks and soils, and deposition into the lake basin under mudflows. At that time, montane savanna and forest formation were already established suggesting predominance of wet climate. However, from 7000 to 3000 cal yr BP, a decline of detrital input occurred. Also, forest formation and pteridophytes were declined, while palms and macrophytes were remained relatively stable, indicating that water levels of the lake is likely dropped allowing the development of plants adapted to subaerial condition under drier climate conditions. After 3000 cal yr BP, eutrophication and low accommodation space lead to high lake productivity and the final stage of the lake filling respectively, and forest formation may has acquired its current structure, which suggests return of wetter climate conditions.
Acesso aberto (Open Access)
Mapeamento de ambientes costeiros tropicais (Golfão Maranhense, Brasil) utilizando imagens de sensores remotos orbitais
(2009) TEIXEIRA, Sheila Gatinho; SOUZA FILHO, Pedro Walfir Martins e
This paper presents the results of coastal environmental mapping of Golfão Maranhense, Brazil, using a methodological approach that includes: (a) integrated analysis based on digital image processing of Landsat-4 TM, SPOT-2 HRV, RADARSAT-1 SAR (Synthetic Aperture Radar) and SRTM (Shuttle Radar Topography Mission) data; (b) geographic information system; (c) field surveys related to geomorphology, topography and sedimentology. Mapped environments were grouped into four sectors: Sector 1, with salt marsh, fresh marsh, estuarine channel and intermittent lake; Sector 2, embracing coastal plateau, fluvial floodplain, sandflats, macrotidal beach, urban areas, artificial lakes and mudflats; Sector 3, including, paleodunes covered with grass, mangroves and mixed intertidal banks; Sector 4, constituted by mobile dunes. In addition, perennial lakes, ebb-tidal deltas and supratidal sandflats were recognized. Digital image processing visual analysis of orbital remote sensing data in association with geographic information system, proved to be effective in tropical coastal mapping, allowing the generation of products with good accuracy and cartographic precision.
Acesso aberto (Open Access)
A Planície Costeira Bragantina (NE do Pará): influência das variações do nível do mar na morfoestratigrafia costeira durante o holoceno
(Universidade Federal do Pará, 1995-11-20) SOUZA FILHO, Pedro Walfir Martins e; EL-ROBRINI, Maâmar; http://lattes.cnpq.br/5707365981163429
The Bragantina Coastal Plain, with an approximate area of 1,570 Km2, is located in the Cretaceous Coastal Basin of Bragança-Viseu (NE of Pará). The architecture of the basin and its paleotopography, associated with recent tectonic movements, have controlled the distribution and thickness of tertiary and quaternary deposits. This coastal plain is a depositional system called macrotidal (6m), developed under conditions of a hot and humid equatorial climate, with a well-defined rainy and dry season and an average annual precipitation equivalent to 3,000 mm. The geomorphology of the area is compartmentalized into three morphological patterns: (1) alluvial plain, with fluvial channel, levees and floodplain; (2) estuarine plain, with estuarine channel compartmentalized in estuarine funnel, straight and meandering segment and upper course channel, tidal streams and floodplain; (3) coastal plain, with saline marsh environments (internal and external), tidal plain (supratidal, intertidal and sandy plain with tidal flats), chenier, coastal dunes and beaches. The study of morphostratigraphy allowed the characterization of 11 morphostratigraphic units: (1) floodplain, (2) levees, (3) channel bar, (4) supratidal mangrove, (5) saline marsh, (6) intertidal mangrove , (7) sandy plain, (8) bar in point, (9) coastal dunes, (10) chenier and (11) beaches and 4 stratigraphic facies: (1) river sand, (2) marine/estuarine sand and mud, (3) sand and mud with heterolithic bedding and (4) mottled muddy sand. The stratigraphic analysis allowed the individualization of three stratigraphic sequences: (1) basal transgressive marine (S1), with fluvial, marshy and shoreface environments; (2) regressive marine (S2), with fluvial, tidal flat, chenier and saline marsh environments and; (3) current transgressive marine (S3) with estuarine and coastal environment. The evolution of this depositional system in the Bragantina Coastal Plain is associated with the sea level oscillations during the Late Holocene. At the height of the Holocene transgression (6,000 years B.P.), a rise in sea level invaded coastal areas, eroding the Coastal Plateau (Barreiras Group). After this event, the muddy plain prograded, under regressive or stable sea level conditions, on the basal transgressive sandy sheet. Therefore, erosive periods, probably related to rapid sea level rises or climate change, affected the discharge of rivers, allowing the formation of cheniers. Currently, new sandy deposits are migrating over the muddy plain.
Acesso aberto (Open Access)
Reconhecimento e mapeamento dos ambientes costeiros para geração de mapas de ISA ao derramamento de óleo, Amazônia oriental
(2009) BOULHOSA, Messiana Beatriz Malato; SOUZA FILHO, Pedro Walfir Martins e
Accidents related to exploration and oil transport are a threat to coast zones around the world. Oil spills are an ecological disaster that may cause irreparable damage to the environment. In the northeast cost of Pará state the intense flow of ships and rafts transporting petroleum and flowed, then the need to establish prevention strategies and administration of the environmental sensitivity about the oil spills in a certain part of Pará state northeast cost. The methodology consisted on processing digital images from remote sensors in the Landsat ETM+7 associated to data from the SRTM (shuttle radar topography mission) digital model of elevation, and to the field data collected in a GIS (geographical information system) environment. The most important results allowed: recognizing and describing five main geomorphological; identifying and classifying nine units of Environmental Sensitivity Rates (ISA) and creation of the Environmental Sensitivity Rates map to oil spill. The remote sensors techniques and SIG proved to be important tools for recognizing coast environments and for generating proposed maps.
Acesso aberto (Open Access)
Spatial distribution of southern brown shrimp (Farfantepenaeus subtilis) on the Amazon continental shelf: a fishery, marine geology and GIS integrated approach
(Universidade Federal do Pará, 2015-12) MARTINS, Déborah Elena Galvão; CAMARGO-ZORRO, Mauricio; SOUZA FILHO, Pedro Walfir Martins e; CINTRA, Israel Hidenburgo Aniceto; SILVA, Kátia Cristina de Araújo
The spatial distribution of the southern brown shrimp Farfantepenaeus subtilis (Pérez-Farfante, 1967) was studied based on industrial fishing fleet activities and is associated with geological and oceanographic characteristics of the benthonic environments on the Amazon continental shelf. Using a geographical information system (GIS) this paper sought to calculate the relative abundance of brown shrimp based on catch per unit effort (CPUE) and compare it with bathymetry, type of sedimentary structure, sedimentation rate and bottom salinity. As a result, we have concluded that the relative abundance (in terms of CPUE) is not uniformly distributed in space. Spatial analysis indicates that commercial trawling efforts were made in the (foreset) region of the subaqueous Amazon delta at depths of 40 to 60 m. In this region, prawn are responsible for the bioturbation of the sediments and the creation of a sedimentary structure called mottled mud. In the foreset region, sedimentation rates progressively increased up to 10 cm.yr-1; re-suspension was reduced and bottom salinity was high (~ 36). It appears that all of these factors define a stable muddy area with intense bioturbation. This notable biological activity is to be explained by the occurrence of a high F. subtilis abundance that appears to originate in a microbial loop. We concluded that by combining fishery information with environmental data from a GIS, it was possible to identify abundance distribution patterns for southern brown shrimp and other economically important fishery resources and to understand how they change on a large spatial-scale.
Acesso aberto (Open Access)
Use of synthetic aperture radar for recognition of Coastal Geomorphological Features, land-use assessment and shoreline changes in Bragança coast, Pará, Northern Brazil
(2003-09) SOUZA FILHO, Pedro Walfir Martins e
Synthetic Aperture Radar (SAR) images are being used more extensively than ever before for geoscience applications in the moist tropics. In this investigation, a RADARSAT1-1 C-HH SAR image acquired in 1998 was used for coastal mapping and land-cover assessment in the Bragança area, in the northern Brazil. The airborne GEMS 1000 X-HH radar image acquired in 1972 during the RADAM Project was also used for evaluating coastal changes occurring over the last three decades. The research has confirmed the usefulness of RADARSAT-1 image for geomorphological mapping and land-cover assessment, particularly in macrotidal mangrove coasts. It was possible to map mangroves, salt marshes, chenier sand ridges, dunes, barrier-beach ridges, shallow water morphologies and different forms of land-use. Furthermore, a new method to estimate shoreline changes based on the superimposition of vectors extracted from both sources of SAR data has indicated that the shoreline has been subjected to severe coastal erosion responsible for retreat of 32 km2 and accretion of 20 km2, resulting in a mangrove land loss of almost 12 km2. In an application perspective, orbital and airborne SAR data proved to be a fundamental source of information for both geomorphological mapping and monitoring coastal changes in moist tropical environments.