Navegando por Assunto "Litoral"

Agora exibindo 1 - 15 de 15

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)
Cestóides da ordem Trypanorhyncha em peixes de importância comercial capturados no litoral amazônico
(Universidade Federal do Pará, 2008) DIAS, Lilian de Nazaré Santos; MATOS, Edilson Rodrigues; http://lattes.cnpq.br/7895814591867510; PAIVA, Rosildo Santos; http://lattes.cnpq.br/0510818763187669
The purpose of this study was to identify the parasite fauna, particularly the cestode Trypanorhyncha the order, which affects market value of fish caught in Amazon coastal and assess the possible impacts on fisheries production industry. We examined 328 samples of five species of fish: Cynoscion acoupa, Macrodon ancylodon, Plagioscion squanosissimus, Centropumus undecimalis, Arius Parkeri. It made the measurement of its total length and weighing fish, filleting in the regions examined body, muscles and serous. The blastocyst, Trypanorhyncha were removed and sent for laboratory Azevedo Carlos. All species surveyed were parasitized by Trypanorhyncha, totaling 283 (73.78%) parasitized copies. The species Callitetrarhynchus gracilis showed higher prevalence parasite. Poecilancistrium caryophyllum was the most infect the species of fish studied, followed by Pterobothrium crassicolle and Pterobothrium heteracanthum and Callitetrarhynchus speciosum, infected Cynoscion acoupa and Arius Parkeri respectively. The regions abdominal muscles and backside were the most affected.
Acesso aberto (Open Access)
A comunidade zooplanctônica em um canal de maré no estuário do rio Caeté, Bragança (Pará, Brasil)
(Universidade Federal do Pará, 1999-04-30) PERES, Ariadne da Costa; ISAAC, Victoria Judith; http://lattes.cnpq.br/3696530797888724
There are few studies mede about zooplankton in estuaries of Bragança region, Pará State. This work was done in a tidal creek, named Furo do Chato, next to Ajuruteua, Bragança's district which is part of Pará State seashore and aimed to study lhe zooplankton qualitative and quantitative composition, as well as lhe sazonal variations and the environmental effect variables of the zooplankton composition. From August/96 to January/97 every three weeks for a period of 24 hours, zooplankton samples were taken every two hours. Furo do Chato is a tida l creek with strong coaste! influence. Hence the great majority of lhe zooplankton categories found are from coaste! water. Besides holoplankton and meroplankton components, lhe zooplankton samples from Furo do Chato has a strong bentonic component. Ten phyla were identified: Protozoa, Mollusca, Chordata, Annelida, Cnidaria, Arthropoda, Urochodata, Chaetognatha, Nematoda e Bryozoa. The Copepoda class had higher representative, even for density, biomass as well as occurrence frequency in the community. The most abundant and frequent Categories (>40%) were Pseudodiaptomus marshi, Acartia lilljeborgi, Acartia tansa, Harpacticoida, Sagitta sp., Oikopleura dioica, Cnidaria, Isopoda, crabs zoeas, shrimps post-larvae and fish larvae. The average densities and biomass were low (1,07 indiv./m³ e 16,43 mg/m³). The zooplankton community is more abundant in the transition months than in the dry period. The highest abundances took place at night and during the spring lides. Tide, salinity and different moon phases did not infiuence in the zooplankton as a whole, but only in some categories isolated.
Acesso aberto (Open Access)
Diagnóstico da pesca no litoral paraense
(Universidade Federal do Pará, 2004-02) SILVA, Bianca Bentes da; ISAAC, Victoria Judith; http://lattes.cnpq.br/3696530797888724
Acesso aberto (Open Access)
Diversidade e distribuição do gênero Alvania (Mollusca, Gastropoda: Rissoidae) no litoral brasileiro
(Universidade Federal do Pará, 2012-04-13) SILVA, Luciana Soares da; SANTOS, Franklin Noel dos; http://lattes.cnpq.br/2437036625902034; VENEKEY, Virág; http://lattes.cnpq.br/1106411624280455
The Rissoidae Gray, 1847 are composed of small shells or micro-shells, abundant in the oceans of the world. A great diversity of species of this group is found in areas of low tide and along the coast, where there is a higher occurrence of algae, rocks, corals and other places that provide shelter, however, they also occur in many areas of the deep sea. In Rissoidae, Alvania is one of the most diverse concerning species number with frequent descriptions or re-descriptions within this genus. The aim of this study was to determine the diversity and distribution of Alvania, therefore, describe and expand the knowledge of the fauna in Brazilian littoral, through conquiological analyses, beyond the geographical and bathymetric distribution of the species of this genus. All material is originated from collections of museums, oceanographic expeditions and also material collected in the second half of 2010 and in 2011. Previously, seven species were listed for the west cost of the Atlantic, and in the present study three of these species were not found. We analyzed 3599 specimens belonging to ten species: Alvania auberiana (Orbigny, 1842); Alvania cancapae Bouchet & Warén, 1993; Alvania colombiana Rommer & Moore, 1988; Alvania faberi De Jong & Coomans, 1988; Alvania tarsodes (Watson, 1886), Alvania valeriae Absalão, 1993 and four possible new species: Alvania sp. nov. 1, Alvania sp. nov. 2, Alvania sp. nov. 3, Alvania sp. nov.4.
Acesso aberto (Open Access)
Episode of Low Level Jets in the north and northeast coast of state of Para: a case study of 2002 april 21st to 22nd
(2008-09) SOUSA, Adriano Marlisom Leão de; CAMPOS, Claudia Rejane Jacondino; ROCHA, Edson José Paulino da
In this study the characteristics of the vertical structure of an episode of Low Level Jets (LLJ) occurring in the coast of Para is described. Radiosonde data of Ajuruteua city in Bragança collected during the DESMATA Experiment (Impact of the Deforestation the Atlantic Coast of the Amazonian), taking place in 2002, from April 08th to 22th, are used. Among the detected cases during the rainy period, one specific case with 12 hours duration, average velocity of 15m/s and directed from NE to E in the point of maximum velocity was selected. The observational results have indicated that this LLJ located in the coast of Para was due to the combined action of two factors: (1) inertial oscillation and (2) superficial baroclinicity. These two combined factors sustained this LLJ with velocities between 10 and 13m/s during the day and between 14 and 16m/s during the night, at an average altitude of 800m above surface.
Acesso aberto (Open Access)
Estrutura das assembléias de macroinvertebrados de substratos rochosos no litoral de Curuçá, nordeste do Pará, Brasil
(Universidade Federal do Pará, 2011-04-15) MORAIS, Gisele Cavalcante; LEE, James Tony; http://lattes.cnpq.br/1693070833836566
Acesso aberto (Open Access)
A ictiofauna de poças rochosas de maré: padrões de distribuição associados ao espaço e ambiente
(Universidade Federal do Pará, 2012) RUFFEIL, Tiago Octavio Begot; MONTAG, Luciano Fogaça de Assis; http://lattes.cnpq.br/4936237097107099
Within studies of biological communities the search for occurrence and distribution patterns is acquiring space in researches in recent decades. Knowledge of the community structure and their relations, associated with interaction of these organisms with the environment, give necessary subsidies for the maintenance of these communities and relevant information for conservation and management plans. This way, the aim of this work was analyze the effect of environment and space on the structuration of the fish assemblage of rocky tidepools, describing the occupation patterns of these species in this environment and testing the hypothesis of the space having strong effect on the ichthyofauna organization. It was sampled 80 rocky tidepools in Amazon coastal zone, being 40 of the rainy period and 40 of the dry period of 2011. These pools are localized in five beaches of the Pará coastal zone and their volume, distance of the margin and physical-chemical parameters of the water (as pH, temperature and salinity) were measured. A total of 1.311 fishes were sampled, being 633 individuals of rainy season and 648 of dry season. The specimens represent nine orders, 14 families and 21 species. Perciformes was the most abundant order, within B. soporator and L. jocu as the most representative species. Obtained results in BioEnv process showed that abiotic variables (pH, temperature and volume) are not responsible for the organization of the community. Calculation of β diversity evidenced a wide variation of the data, including since the total substitution of the species to identical communities, considering the occurrence and abundance. DCA pointed that the pluviometric period is not determinant on species distribution, as result of the lack of difference in the composition among periods. The effect of space and environment on the community was low, since the larger part of variation was not explained with environmental variables, as the second analysis, where it was utilized the variables defined with the BioEnv process. Following the same pattern, the partial RDA used with the most correlated variables showed that: 6% explained by environment, 4% by space, 2% by environment and space, and 88% by other factors. The obtained results in these analyses prove that abiotic factors measured, likewise the distance among samples, are not determinant in composition and distribution of tidepools ichthyofauna. These data refute the hypothesis of the space having influence on the organization of the ichthyofauna, since the environmental conditions experience constant disturbances caused by tidal movement. In doing so, the species that occupy this environment showed themselves adapted, and for this reason they would not have their distribution affected by the variation of environmental parameters at this scale, responding only for the space effect.
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)
Mineralogia e geoquímica de sedimentos de manguezais da costa amazônica: o exemplo do estuário do rio Marapanim (Pará)
(2008-03) BERRÊDO, José Francisco; COSTA, Marcondes Lima da; VILHENA, Maria do Perpétuo Socorro Progene; SANTOS, Josiana Torres dos
The mangroves of the Para state represents an important segment of the Brazilian north coast on the ones which little it is known of the geological characteristics and it relationships with source areas. This research was accomplished in the Marapanim river estuary, in the Para coast, to demonstrate the contribution of continental sediments for the constititution of the mangrove's sediments. The mangrove's sediments and the Barreiras Formation sediments and soils (main continental sources) were collected. In the mangrove's sediments grain size, determination of the carbon (C%), pH and Eh measures and interstitial salinity was made. The mineralogical determination and the multi-elementary geochemistry was made in the sediments muddy and terrigenous adjacents sediments for comparisons. The mangrove's sediments are clayey silty (> 90%), with the carbon values among 0,75 to 3,5%. The main mineralogy is composed by quartz, goethita, hematite, kaolinite, illite, besides zircon, tourmaline, staurolite and cianite as accessories, what indicates contribution of the Barreiras Formation sediments and sediments muddy. It is common the occurrence in these mangroves the neoformated minerals as: smectite, K-felspars, pyrite, halite, gipsum and jarosite. The enrichment in SiO2, Al2O3, Fe2O3 and TiO2 in the mangroves and the low tenors in trace metals reflects the tropical climate and the mineralogical composition of the source area, enriched in quartz and caulinite, with low tenors in K2O, Na2O, MgO and CaO. The chemical composition associated to the organic matter, abundant diatoms besides Fe, S and the marine contributions of Cl-, Na+, K+, Ca++ and Mg++, identify the deposicional ambient and the autigenics minerals. The concentrations and the geochemical behaviour of the trace metals in the mangroves corroborates the outstanding contribution of the continental source area. Those sediments presents the prevalence of the Light Rare Earth Elements (LREE) on the Heavy Rare Earth Elements (HREE) with high reasons of Th/Co; La/Th; La/Sc; La/Co and Zr/Sc and Th/Sc and Ba/Co, elements present in the felsic igneous rocks that originated the continental sediments.
Acesso aberto (Open Access)
Política ambiental costeira: uma análise do seu impacto em Bragança-PA
(Universidade Federal do Pará, 2011-10-05) SOUSA, Thalita Adriana Ferreira de; MATHIS, Armin; http://lattes.cnpq.br/8365078023155571
This dissertation discusses coastal environmental policy, structured in the National Plan of Coastal Management - Federal Law Nº 7.661/88, the scope of the municipality of Bragança/Pa. It shows how government intervention in the issue of the use of natural resources and coastal sprawl can change the situation of environmental degradation on the coast bragantina. The main objective was to analyze the impacts (the effects and products) of the policy in Bragança. For this, it was discussed theoretically on the structure of public policies, political and administrative decentralization, multilevel governance and government failures in environmental management. It was found that the management of natural resources and land held in the Brazilian coastal zone GERCO driven program during his 20 years of existence, is limited and differentiated in the coastal states and municipalities. The results indicate progress, shortcomings and mistakes in managing coastal bragantina. For the very form of organization of this program is not effectively integrated, decentralized, participatory and coordinated, in addition to financial incentives for the smallest application of its planning and management tools.
Acesso aberto (Open Access)
Population structure of Lutjanus purpureus (Lutjanidae - Perciformes) on the Brazilian coast: further existence evidence of a single species of red snapper in the western Atlantic
(2012-12) GOMES, Grazielle Fernanda Evangelista; SAMPAIO, Maria Iracilda da Cunha; SCHNEIDER, Horacio
The present study focus on the mitochondrial control region to investigate phylogeographic patterns and population structure in Lutjanus purpureus, and to evaluate the genetic similarity between L. purpureus and L. campechanus. For the initial analysis, 810 base pairs sequence from control region were obtained from 239 specimens of L. purpureus collected from four localities off the Brazilian coast. The results revealed the presence of a single panmictic population characterized by high values of genetic diversity. The 299 base pairs hypervariable portion were used for the combined analysis of L. purpureus and L. campechanus, being 275 haplotypes identified in the 414 specimens. Phylogenetic tree and haplotype network did not indicate phylogeographic substructuring between the two species, but rather an intense intermingling of individuals. Considering their marked morphological similarity, the molecular data presented here indicatethat only one species of red snapper exists in the western Atlantic.
Acesso aberto (Open Access)
Unidades de relevo em zona costeira estuarina: municípios de Colares e Santo Antônio do Tauá
(Universidade Federal do Pará, 2007-08-20) BARBOSA, Estêvão José da Silva; FRANÇA, Carmena Ferreira de; http://lattes.cnpq.br/5723672412810714
This work identified and argued the geomorphic units (relief) of Colares and Santo Antônio do Tauá municipalities, State of Pará, Brazil. It has Geomorphology as subject. The studied area is located in eastern portion of Amazon River Estuary (“Golfão Marajoara”), northeast of Marajó bay, at estuarine coastal zone. In this study was used: bibliography, maps, remote sensing data and work fields. The analysis was made by two scales. First Scale is represented by the Amazonian Coastal Zone, which shows low altitude, sedimentary lithology, macrotidal tidal range, tropical and wet climate and stronger river discharges. This regional coast was produced by relative sea-level fluctuations, climatic changes, and tectonic dynamics occurred throughout Late Cenozoic. Eastern portion of Amazon River estuary is formed by Pará River Estuary – Marajó Bay, a typical tidal river or river-dominated estuary, although it has tidal influence. River discharge is main component of the estuarine dynamics, sedimentary constitution and biota organization. Pará River Estuary is a coastal environment with less energy of waves and littoral currents than the shore of Northeast Pará. In the second scale, were identified eight geomorphic units: sandy estuarine channel; tidal mud bank; tidal mud flat; estuarine beach; dune-beach ridge; tidal influence alluvial plain; alluvial plain; plateau. Only plateau is a erosive relief unit. The research also deals spatial distribution of these geomorphic units, in two sectors. Sector 1 is located in western portion of studied area. It is largely influenced by tides, and has different depositional relief units. The major geomorphic unit is tidal influence alluvial plain, which results of transition between marine and alluvial factors. Freshweater swampy formations followed mangroves toward landward due to reduced saline influence in the channels. Sedimentary distribution is marked by sand bottom channels, and mud deposits in the margins. Beachs are shorts, commonly covered by mud sets because less wave energy and crucial role of tidal current, discharges action in the coastal dynamics. Dune-beach ridges localized landward coastal plain are the indicative its progression. In this sector, plateaus are discontinuous due to erosion and deposition by tidal, flow channels and rains. Sector 2, localized in eastern portion of studied area, has no tidal influence. It shows a relief little compartmented, with large plateaus dissected by rivers. Fluvial action formed valleys with narrow alluvial plains, which demonstrated a greatest erosive surface in the sector 2.
Acesso aberto (Open Access)
Variação nictemeral do microfitoplâncton em um estuário do nordeste paraense, Brasil
(Universidade Federal do Pará, 2010-06-18) COSTA, Brenda Oliveira da; PAIVA, Rosildo Santos; http://lattes.cnpq.br/0510818763187669
This study’s object was to get to know micro phytoplankton’s diversity, as its nyctemeral variation related to environmental factors on Curuçá river (Curuçá, PA – Brazil). Twelve phytoplankton samples were collected in 3 collecting spots next to a Littopnaeus vannamei sea shrimp farm in a 24 hour time, during spring tides on the 14th and 15th of august 2004 and on the 24th and 25th of January 2005. It was determined its specific composition and phytoplankton density (org.L-1), analyzed its occurrence rate, diversity and evenness, grouping and main components. Physicochemical parameters did not show any significant variability between the collecting months, though it was observed an important rainfall influence on the salinity, filing the bottom values in jan/05 and the top ones in aug/04. There were 170 registered taxa that belong to the Baccilariophyta (149), Dinophyta (16), Chlorophyta (3) and Cyanobacteria (2) divisions. Bacillariophyta had the higher number of species shown, higher occurrence and density (97.59%). A few showed high abundance rates. During August the phytoplankton community is dominated by Bacteriastrum hyalinum, Bellerochea horologicalis, Chaetoceros curvisetus, Dimerograma dubium, Dytilium brigtwelli, Pseudo-nitzschia seriata and Skeletonema costatum. In January predominated Chaetoceros pseudocrinitus, Chaetoceros curvisetus and Skeletonema costatum. Neritic marine planktonic species, oceanic marine planktonic, neritic-oceanic marine planktonic predominated the samples. Specific diversity oscillated from 0.7591 bits.org-1 to 1.3314 bits. org-1 generally characterized by a low to very low diversity, showing a poorly diversified structure. Phisicochemical parameters and density among species was the main factor to determinate sample grouping in two big groups: the first one with august samples and the second one with January samples. Its component analysis showed that despite its low physicochemical variation amongst the collecting months, the rainfall and salinity variations were really important on the species density, causing an increase on phytoplankton density in January.
Acesso aberto (Open Access)
Zona costeira resiliente: um estudo sócio-ecológico no Nordeste paraense
(Universidade Federal do Pará, 2010-12-22) CABRAL, Neila Waldomira do Socorro Sousa; MATHIS, Armin; http://lattes.cnpq.br/8365078023155571
This doctoral thesis presents the conceptual and methodological contributions of systemic analysis involving social sciences and natural sciences in the debate about the applicability of sustainable development on the costal Amazon territory. The main challenge is to use an innovative theoretical framework that articulates social-ecological systems - SES and resilience in the analysis of primary and secondary data. The research focuses on the bragantina coastal region, and uses the social (communities of fishermen) and ecological (mangrove) systems as the sampling area. The program “Dynamics and Management of Mangrove Areas – MADAM”, involving ten years of interdisciplinary research, serves as the main source of information. Based on the concepts of resilience and SES, this thesis analyzes the relationship between the use of natural resources and the local organization and socio-economical structure. The objective is to analyze the resilience of Para’s coastal socio-ecological system, based on the ongoing process of socio-economic development, identifying what changes are generated, and how the coastal system reacts and adapts to new settings. The goal is to provide alternatives for the correct development of the region studied. The result reflects a panorama of current conditions of the coastal bragantina region. In this work it is shown that the main facts contributing to increase or decrease of the region's socio-ecological resilience, understood as the ability to self adapt and reorganize in the face of changes and disruptions, are particularly endogenous driving forces, especially the social capital and the Local Ecological Knowledge - CEL, which potentially provides a feed-back for the sustainable planning in the Amazonian shore region.