Dissertações em Oceanografia (Mestrado) - PPGOC/IG

URI Permanente para esta coleçãohttps://repositorio.ufpa.br/handle/2011/16440

Navegar

Agora exibindo 1 - 20 de 29

Acesso aberto (Open Access)
Análise ecológica da ostracofauna (crustacea) e meiofauna bentônica associada como bioindicadores ambientais na ilha de Cotijuba, Belém (PA), Amazônia
(Universidade Federal do Pará, 2025-02-27) BRITO, Maurício de Souza; PEREIRA, Ana Paula Linhares; http://lattes.cnpq.br/8369046011837903
The uncontrolled occupation of environmental protection areas (APA) in Belém-PA and candidates for APA, such as Cotijuba Island, has intensified the environmental impacts in the region. To mitigate these effects, Conservation Paleobiology integrates historical data on the distribution of fauna and flora, connecting past, present, and future. In turn, ostracods, small crustaceans sensitive to environmental variations, which are part of the benthic meiofauna, provide information about changes in ecosystems through the analysis of their communities and shells, formed from the calcium carbonate in the water. In this way, the survey of the ostracofauna and associated meiofauna on the island of Cotijuba allowed the use of these groups as bioindicators. The research was conducted during the rainy, transitional, and less rainy seasons, at two beaches: Flexeira, less impacted, and Farol, more influenced by human activities. During the campaigns, surface samples were collected in the inframarine, intertidal and supramarine zones, as well as sediment cores, physico-chemical water measurements, and beach profiles. The results showed Farol beach as reflective and Flexeira beach as dissipative, in addition to physical-chemical parameters with low influence on the organisms. The benthic meiofauna recorded 10 distinct classes: Oligochaeta, Polychaeta, Insecta (Diptera and Trichoptera), Malacostraca (Amphipoda), Arachnida, Ostracoda, Hydrozoa, Gastropoda, Bivalvia, and Rhabditophora. Approximately 84% of the specimens are from Flexeira beach, with this proportion being higher when only ostracods are analyzed (89%). Despite the lower abundance at Farol beach, a large number of cocoons of Trichoptera pupae were observed, known for their sensitivity to pollution and environmental changes, indicating a relatively healthy environment. However, a low abundance of ostracods was observed, which may be related to abiotic factors, such as the type of beach and coarse sediments. Moreover, the overall abundance of meiofauna in Cotijuba was also considered low, even without indications of significant anthropogenic intervention, which suggests a relationship between the low number of specimens and hydrodynamic conditions that intensify erosive and depositional processes. The record of a new species is highlighted: Cyprideis cotijubensis sp. nov., as a potential bioindicator of recent ostracofauna in river estuaries in the Amazon. The project also resulted in the digital book “Cartilha Digital Preserva Amazônia”, aimed at raising awareness about the conservation of the Amazon.
Acesso aberto (Open Access)
Análise multitemporal (1991-2021) da linha de costa (trecho Calçoene - Cabo Norte), costa atlântica do estado do Amapá.
(Universidade Federal do Pará, 2023-08-21) SILVA, Rhuan Rodrigo Pereira e; EL-ROBRINI, Maâmar; http://lattes.cnpq.br/5707365981163429; https://orcid.org/0000-0001-7850-1217
The coastline (LC) is highly dynamic due to its geographic position adjacent to the mouth of the Amazon River estuary. This region is characterized by meteorological forcings, such as a semihumid equatorial climate, high rainfall (> 2,600 mm. year-1), winds (3 to 9 m. s-1), and extreme events (El Nino - 1997/1998 and 2015/2016; La Nina - 1999/2000 and 2010/2011). It is also influenced by hydrological forcings, including water and solid discharge from the Amazon River (175,000 m³ s-1 and 1,200 Mt. year-1, respectively), and oceanographic forcings, such as hyper-tides (up to 12 m), tidal currents (2 m. s-1), waves (up to 3 m in height), and currents (up to 3 m. s-1). This study aims to analyze the multitemporal variation of the LC between the mouths of the Calçoene and Sucuriju rivers, and at the Maracá-Jipioca Ecological Station, from 1991 to 2021. The methodology includes a literature review, acquisition of LANDSAT satellite images (1991, 2000, 2008, 2014, and 2021), LC vectorization, and the application of DSAS to quantify accretion (m) and erosion areas (m) of the LC, determine retreat and advance rates (m/year and m²/year) between the mouths of the Calçoene and Sucuriju rivers, and create change polygons at the Maracá-Jipioca Ecological Station. The study area experienced predominant erosive dynamics, with an average LC retreat of 12 m. year-1 and 1.4 km² of erosion in the Calçoene-Sucuriju stretch, and 2 km² of erosion at the Maracá-Jipioca Ecological Station with an annual average retreat of approximately 18 m. Due to erosive dynamics, the study area requires special attention from public managers to prevent any type of anthropic interference that could intensify this process.
Acesso aberto (Open Access)
Análise multitemporal da linha de costa e indicadores de erosão na praia da Ponta D’Areia, ilha do Maranhão: diagnóstico dos impactos de obras costeiras
(Universidade Federal do Pará, 2024-08-29) SANTOS, Alessandro Ferreira dos; LIMA, Leonardo Gonçalves de; http://lattes.cnpq.br/5984899472616752; RANIERI, Leilanhe Almeida; http://lattes.cnpq.br/3129401501809850; https://orcid.org/0000-0002-9870-4879
The coastal zone is defined as the geographical transition space between the ocean and the continent. In the state of Maranhão, it comprises five sectors, including the Maranhão Golfão. Ponta D’Areia beach is located northwest of the Maranhão Island, making up this sector where tides can reach up to 7.2 meters in height. The beach is approximately 2.5 km long, bounded by the Anil River and São Marcos Beach. In 2014, the construction of a coastal groin was completed at Ponta D’Areia beach, aimed at containing erosion and preventing sedimentation towards the Anil River. In this context, the research addressed the following questions: (a) How did the shoreline change over 27 years? (b) What are the erosional, depositional, and stable sectors from a morphodynamic perspective, considering the period before and after the construction of the coastal groin at the beach? It was believed that the rigid engineering structure was intended to stop the sedimentation at the mouth of the Anil river, which did not occur. As a result, it was necessary to extend the groin to an "L" shape to attempt to curb sedimentation, but this led to continued erosional activity at the northeastern end of the beach. Therefore, the objective of this research was to conduct a multitemporal analysis of the Ponta D’Areia shoreline from 1996 to 2022 and assess its current vulnerability to erosion. The methodology included: (1) on-site observational analysis to fill out pre-defined tables related to coastal erosion geoindicators and collection of surface beach sediments in November 2022 and April 2023, during the dry and rainy seasons, respectively; (2) beach topography survey and orthophoto acquisition through drone flights in April 2023; (3) multitemporal shoreline analysis from 1996 to 2022 using Landsat satellite images, ArcGIS software, and the Digital Shoreline Analysis System (DSAS) extension, as well as shoreline projections for 10 and 20 years into the future; (4) application of the Coastal Erosion Vulnerability Index (CEVI) in three coastal sectors, through the evaluation of natural and anthropogenic parameters; and (5) assessment of the impacts of coastal engineering works on Ponta D’Areia beach. Results showed variations in the shoreline from -64.63 meters (-3.46 m/year: erosion) to 32.15 meters (2.39 m/year: acretion) from 1996 to 2022, with a projected advance of 157.76 meters (4.94 m/year) and retreat of -123.26 meters (-3.68 m/year) by 2032, and a projected advance of 101.93 meters (1.48 m/year) and retreat of -141.35 meters (-1.63 m/year) by 2042. The morphodynamic state of the beach was identified as dissipative through topographic mapping with a drone, and moderate vulnerability to coastal erosion in Sector I, the marina sector, which had the lowest CEVI of 4. Sector II, the groin sector, had CEVI of 6.37 (moderate vulnerability), while Sector III, the Lighthouse sector, had a CEVI of 6.8, indicating high vulnerability to coastal erosion. It was possible to observe how meteo-oceanographic processes (waves, littoral drift, tidal currents, winds, and estuarine discharge) are influencing shoreline variation, as well as human interventions (coastal occupation and construction of rigid structures). Coastal accretion intensified at the beach after the anthropogenic intervention with the groin construction. It is concluded that the multitemporal analysis of the shoreline in the study area between 1996 and 2022 revealed significant variations influenced by natural and anthropogenic factors. Even with human interventions to alter the resulting sedimentation caused by meteo-oceanographic agents, these natural processes continue to intensely shape the region's coastal dynamics and are mainly responsible for variations in the shoreline.
Acesso aberto (Open Access)
Aplicabilidade de um sistema de baixo custo para o monitoramento de dados meteoceanográficos na zona costeira Amazônica
(Universidade Federal do Pará, 2025-04-23) SOTÃO, Daniel da Silva; ROSÁRIO, Renan Peixoto; http://lattes.cnpq.br/8003860457518342; https://orcid.org/0000-0003-2913-0514
This study aimed to develop, implement, and validate a low-cost Continuous Monitoring Prototype (CMP) to collect meteoceanographic data in the Amazon Coastal Zone (ACZ), a region vulnerable to climate change and lacking environmental data. The system, built with an ESP32 microcontroller, integrates sensors for air temperature and relative humidity (HDC1080 and AM2302), atmospheric pressure (BMP280 and MS5611), water temperature (DS18B20), tide level (HC-SR04), precipitation, and wind speed and direction. Sensor validation was performed by comparing the collected data with reference equipment: a CICLUS PRO weather station (CWS) and a Sonlist Levelogger 5 LTC recorder (CTDlog). The CMP conducted four joint test campaigns with the CWS and CTDlog, totaling 56,221 records. Linear regression was applied to develop calibration equations for each sensor. Calibration quality was assessed using the coefficient of determination (R²), root mean square error (RMSE), Pearson correlation coefficient, and residual analysis. The HDC1080 and AM2302 sensors showed excellent performance for temperature measurement, with R² > 0.9, RMSE < 0.2 °C, mean absolute residual (MAE) < 0.12 °C, and very strong Pearson correlation (r ≥ 0.9). However, they exhibited instability in relative humidity measurements (R² ≈ 0.64; RMSE ≈ 3.46%; MAE ≈ 2.52%). The performance of the BMP280 and MS5611 pressure sensors was initially affected by internal heating, but after thermal compensation, they achieved R² values between 0.88 and 0.99, RMSE from 0.17 to 0.45 hPa, and MAE from 0.11 to 0.34 hPa, with the BMP280 showing superior performance. The DS18B20 water temperature sensor showed very strong correlation, with R² ≈ 0.94, RMSE ≈ 0.036 °C, and MAE ≈ 0.021 °C, proving highly promising. The HCSR04 sensor stood out as the most accurate, with R² ≈ 0.99, RMSE ≈ 2.6 cm, and MAE ≈ 1.9 cm. Precipitation and wind sensors presented inconsistencies and require further testing. The total production cost of the CMP was BRL 952.75, representing savings of 86.19% compared to the CWS (BRL 6,897.00) and 96.14% compared to the CTDlog (BRL 24,677.29). When compared to equivalent equipment, the CMP achieved at least 66.33% cost reduction compared to basic stations and 87.3% compared to lower-cost temperature and water level recorders. The CMP proved to be a viable, economical, and replicable solution for continuous environmental monitoring in the ACZ, with the potential to fill existing gaps in observation networks, although improvements are still needed to enhance its long-term performance.
Acesso aberto (Open Access)
Avaliação das influências espaço-temporais e de maré nas concentrações de metais em água e sedimentos estuarinos no entorno de um polo industrial amazônico
(Universidade Federal do Pará, 2025-04-25) FERREIRA, Johnata Azevedo; AMADO, Lílian Lund; http://lattes.cnpq.br/3382900147208081; https://orcid.org/0000-0001-7693-8191
Formed by the Tocantins River and smaller tributaries such as the Guamá and Capim rivers, the Pará River Estuary is an important ecosystem, serving as a shelter and reproduction site for many fish species and contributing to nutrient recycling in the aquatic environment. However, this area suffers from constant discharges of domestic and industrial effluents. The town of Barcarena, located in Pará and approximately 40 km from the state capital (Belém), plays a significant role in the state’s economy by hosting an industrial hub focused on the aluminum, kaolin, and steel industries. This study aims to characterize the temporal and spatial variation in the presence of metals and metalloids in both surface water (total, dissolved, and particulate fractions) and sediment across various points with differing levels of urban and industrial influence in Barcarena, PA. Water and sediment samples were collected during different seasonal periods throughout 2023 and 2024. During the sampling period, several phenomena were observed, particularly those related to the El Niño–Southern Oscillation (ENSO). The year 2023 was marked by the occurrence of La Niña, while 2024 was characterized by El Niño conditions. Sampling was performed in triplicate during both low and high tides at each site. Ten different metals (Al, Ba, Cd, Fe, Pb, Mn, Ni, Cr, As, and Hg) were analyzed in both water and sediment samples using Atomic Absorption Spectrometry with Flame Atomization, Graphite Furnace, Cold Vapor Mercury, and Hydride Generation techniques. The results showed no statistically significant differences between the different tidal conditions (high and low tide). Overall, the metals that exhibited higher concentrations across the sites were Al, Fe, Mn, and Ba, in both environmental matrices. This outcome was expected, as these elements naturally occur at high concentrations in the area's geological formation (Barreiras Formation). Although the region presented high metal concentrations, this pattern is most likely related to the local geology. However, anthropogenic factors may also contribute to elevated metal levels, as observed at certain highly impacted sites characterized by poor basic sanitation and direct discharge of domestic effluents and contamination from open-air dumps. These residues ultimately become sources of metal and metalloid input into the environment, especially for elements such as Pb, Hg, and As, in both water and sediment. These elements are often associated with domestic sewage, improper solid waste disposal, and open dumpsites. Our results also highlight important conclusions regarding the influence of ENSO on metal distribution in water and sediment in the Amazon region. Higher metal concentrations in both water and sediment were observed during the El Niño period compared to the La Niña period. Therefore, we conclude that environmental assessments in the Amazon region especially those involving metal monitoring in environmental matrices, should carefully consider the natural background input of these elements into abiotic compartments in order to accurately identify potential contamination arising from anthropogenic activities such as urbanization and industrialization.
Acesso aberto (Open Access)
Bacias hidrográficas urbanas : aspectos socioambientais da bacia do Tucunduba, Amazônia, Brasil
(Universidade Federal do Pará, 2021-09-15) FIGUEIREDO, Camila de Magalhães e Souza; SOUSA-FELIX, Rosigleyse Corrêa de; http://lattes.cnpq.br/1452935151806378; https://orcid.org/0000-0002-3769-0792
The Tucunduba Hydrographic Basin (THB) is the second largest basin in the city of Belém, in Pará. It drains four districts of Belém: Marco, Canudos, Terra Firme and Guamá. It is one of the most densely populated areas in the city, with a population of approximately 200,000 inhabitants. This work aims to analyze the socio-environmental conditions of the Tucunduba Basin, based on the macro-environmental elements needed to understand the dynamics of use throughout the basin. The methodological approaches of the research included the application of a questionnaire to the residents of the THB, a calculation based on the local Urban Quality of Life Index (UQLI), a calculation of the Simplified Environmental Impact Index, an estimate of the per capita sewage discharge of the neighborhoods belonging to the THB and an Environmental Impact Assessment of the physical, biotic and anthropic environments in the 3 sections of the macrodrainage project. Based on the results obtained, the IQVU in the Tucunduba Basin is approximately 0.6, i.e. regular. In addition, the results generated through the simplified environmental impact assessment show that the stretches analyzed have considerable environmental impacts (either high or very high). This demonstrates the precariousness of the services offered to the population and highlights the fragility of local urban management. There is therefore an urgent need for integrated management strategies, the evaluation and monitoring of space, and the provision of services that guarantee a good quality of life and the environment.
Acesso aberto (Open Access)
Caracterização dos padrões morfodinâmicos em cristas de praias na costa amazônica
(Universidade Federal do Pará, 2023-09-29) ROSÁRIO, Edineuza dos Santos; SANTOS, Valdenira Ferreira dos; http://lattes.cnpq.br/1395198888623953; HTTPS://ORCID.ORG/0000-0002-5038-4191; RANIERI, Leilanhe Almeida; http://lattes.cnpq.br/3129401501809850; https://orcid.org/0000-0002-9870-4879
Knowledge of beach environments requires an integrated morphodynamic approach using different spatio-temporal scales, in order to understand the role of coastal and marine processes in modifying beach morphology. There are some important peculiarities about these processes on the beaches of the Amazon region, such as the large hydro-sedimentary discharge from the estuaries, high rainfall rates and the high amplitude and intensity of the tidal currents, which shape the often complex beach systems, such as beach ridges. The objective of this research was to analyze the morphological dynamics of a beach ridge segment located north of the mouth of the Amazon River, in Goiabal (city of Calçoene), in the coastal ocean sector of the state of Amapá.The hypothesis is that the morphological changes in the segment of beach crest under study are influenced by the hydrosedimentary dynamics of the Amazon River. The research methodology was based on three stages: (1) determining the morphology of beach ridges and their changes (beach profile variation, sedimentary deposits and beach classification); (2) analysis of morphosedimentary processes (physical coastal agents such as tides, waves and currents, and sediment supply such as sediment plumes; (3) data integration (correlation between the processes analyzed in stage one and two). The results indicate significant average variations in the morphosedimentation of the Goiabal beach ridge system, with seasonal migration (~24 to ~42 meters) towards the mainland. Erosion and deposition on the ridges and subsequent channels averaged less than 0.30 m along the beach profiles during the seasonal cycle. The oceanographic parameters indicate an average wave height of 0.25 m and an average tidal range of 5 m. Coastal currents are directed west-southwest and there is a predominance of ebb tide currents during the rainy season. The sediment plume of the Amazon River was closer to the study area during the rainy season (~15 to 25 km), with a predominance of ebb tide currents. Thus, it can be concluded that the segment of beach crest studied has a greater influence from the Amazon River sediment plume during the rainy season, intensifying the deposition of fine sediments. The displacement of beach ridges and the supply of sediment have a strong relationship with tidal dynamics in the region.
Acesso aberto (Open Access)
Compreendendo as percepções sobre os potenciais impactos das mudanças climáticas em comunidades costeiras: um estudo de caso na área marinha protegida de Soure, costa amazônica brasileira
(Universidade Federal do Pará, 2024-04-24) WANDSCHEER, Jéssica Yamila Leiva; ROSÁRIO, Renan Peixoto; http://lattes.cnpq.br/8003860457518342; https://orcid.org/0000-0003-2913-0514
The study explores the perceptions of RESEX Soure communities regarding climate change, examining the complex relationships between these coastal communities and environmental changes. The research employed a structured questionnaire administered to 288 participants, representing 20% of the registered beneficiaries of the unit (Icmbio, 2018). The data collected included quantitative and qualitative insights on awareness, perceived impacts, and adaptation to climate change. The results reveal that 95.14% of respondents have a monthly income of up to one minimum wage (R$ 1,100 in 2021), reflecting the community's economic vulnerability. Regarding education, 61.46% have completed primary school, while only 2.08% have tertiary education. Most participants (58%) were born and continue to reside in the RESEX, relying heavily on extractive activities such as fishing, shellfish collection, and crab harvesting. Respondents reported noticeable environmental changes, including rising temperatures (73%), shifts in rainfall patterns (68%), and biodiversity loss (65%). These changes directly impact livelihoods, particularly fishing, which was identified as the main economic activity by 70% of participants. Additionally, 85% highlighted the importance of public policies and educational programs focused on mitigating climate impacts as critical to community adaptation efforts. While focused on RESEX Soure, the study emphasizes the importance of integrating local knowledge into broader climate adaptation strategies. The findings underscore the need for participatory approaches, scientifically informed and tailored to local realities, to ensure the effectiveness of public policies and enhance the resilience of coastal communities.
Acesso aberto (Open Access)
Desenvolvimento de modelo matemático para simulação de transporte de resíduo plástico em estuário amazônico.
(Universidade Federal do Pará, 2024-05-28) SANTIAGO, Matheus Pamplona; BORBA, Thaís Angélica da Costa; http://lattes.cnpq.br/6210073723678433; https://orcid.org/0000-0001-8084-3128; ROLLNIC, Marcelo; http://lattes.cnpq.br/6585442266149471; https://orcid.org/0000-0002-8601-1514
The increasing use of plastics has raised environmental concerns due to the persistence of these materials in marine ecosystems. It is estimated that trillions of pieces of plastic debris are currently in the oceans, with millions of additional tons entering annually through rivers and other terrestrial sources. There is a gap between models of plastic input to the oceans and field observations, indicating the need for more accurate approaches and simulations based on in-situ data. The Amazon Coastal Zone (ACZ) emerges as a hotspot for the accumulation of plastic waste, especially in vegetated areas close to large urban centers. Although several numerical models have been developed for the ACZ, none have addressed the transport of plastic waste to date. This pioneering study implemented the first mathematical simulation for plastic transport in an urban estuary on the Amazon coast, specifically in the Guajará Bay, using the urban river (Tamandaré river) as a release site due to the availability of in-situ data for plastic parameterization. The hydrodynamic model (D-Flow), validated by the LAPMAR environmental modeling group, and the water quality module (D-Waq), were implemented using the Delft-3D software. The results show that Guajará Bay is more sensitive to plastic contamination during the dry period, characterized by slow transport of water masses and a reduced capacity for renewal. In contrast, during the rainy season, the tendency is to export plastics, due to the system's greater capacity for renewal. The residence time of the waters of the Tamandaré River in the bay varies from approximately 8.28 days in the period of greatest discharge to 31.76 days in the period of lowest discharge, allowing us to estimate that the waste released by the Tamandaré can reach the Tropical Atlantic Ocean in a range of 36 to 63 days, depending on the seasonal season. The study concludes that Amazon estuaries dominated by positive asymmetric tides favor the import of waste during periods of lower flow and increase exports during periods of higher flow. Temporary plastic retention zones were observed in both seasonal periods for marginal regions of low energy and atypical morphology, such as the coastline close to the port of Belém (BG1) and the mouth of the Guamá River (RG). These retention zones are intensified in the dry season and attenuated in the rainy season, depending on local hydrodynamic variability. Although the study analyzed the dynamics resulting from the input of plastics in a single ebb tide, it did not consider the continuous flow and potential accumulation of plastics over time. This work represents an important initial step towards improving the understanding and methodology of plastics transport in the ACZ.
Acesso aberto (Open Access)
Especiação do fósforo em rios urbanos: um estudo de caso dos rios Tucunduba e Tamandaré, Belém/Pará
(Universidade Federal do Pará, 2023-05-24) COIMBRA, Marcus Vinicius Rodrigues; MONTEIRO, Sury de Moura; http://lattes.cnpq.br/4309806566068586; https://orcid.org/0000-0001-9449-7043
Phosphorus (P) is a bioliminating macronutrient that plays an essential role in regulating ecosystem functions and primary productivity in marine and coastal environments. However, when in excessive concentrations, P assumes the role of a pollutant, negatively influencing the ecosystem and causing eutrophication. In Brazil, the problem is maximized in urban centers cut by canals, where there is an intensification of the process of changing the natural conditions of the environment. The speciation of P associated with hydrodynamic processes and the type of urbanization of the environment allows identifying the eutrophication status of these environments. Therefore, the present study seeks to promote understanding of the dynamics of P speciation in two urban rivers, the Tucunduba and Tamandaré rivers, located in the metropolitan region of Belém (Northern Brazil), with the objective of evaluating whether there is variation in P speciation. phosphorus in urban rivers at different time scales. To this end, samples of suspended particulate matter (SPM) were carried out using two different methodologies: the horizontal flow trap (portable traps) and the vertical flow trap (fixed traps). For the extraction of P, the sequential extraction method SEDEX was adopted, which allowed the extraction of five forms: P-Ex, P-Fe, P-Au, PDe and P-Org, in addition to P-Bio. In the Tucunduba river, Total-P concentrations ranged from 20.52 to 100.78 μmol.g-1, with predominance of the P-Fe fraction. In the Tamandaré River, concentrations ranged from 42.36 to 173.88 μmol.g-1 with P-Au predominance. Thus, it was possible to verify that the urban rivers Tucunduba and Tamandaré have high concentrations of P and its species. With these data, it is clear the need to deepen this type of study in these rivers and other urban rivers present in Belém, as well as the need for policies aimed at the recovery and preservation of these, in order to mitigate the problem involving phosphorus and restore the capacity ecosystems of these environments.
Acesso aberto (Open Access)
Especiação do fósforo em rios urbanos: um estudo de caso dos rios Tucunduba e Tamandaré, Belém/Pará.
(Universidade Federal do Pará, 2023-05-24) COIMBRA, Marcus Vinicius Rodrigues; MONTEIRO, Sury de Moura; http://lattes.cnpq.br/4309806566068586; https://orcid.org/0000-0001-9449-7043
Phosphorus (P) is a bioliminating macronutrient that plays an essential role in regulating ecosystem functions and primary productivity in marine and coastal environments. However, when in excessive concentrations, P assumes the role of a pollutant, negatively influencing the ecosystem and causing eutrophication. In Brazil, the problem is maximized in urban centers cut by canals, where there is an intensification of the process of changing the natural conditions of the environment. The speciation of P associated with hydrodynamic processes and the type of urbanization of the environment allows identifying the eutrophication status of these environments. Therefore, the present study seeks to promote understanding of the dynamics of P speciation in two urban rivers, the Tucunduba and Tamandaré rivers, located in the metropolitan region of Belém (Northern Brazil), with the objective of evaluating whether there is variation in P speciation. phosphorus in urban rivers at different time scales. To this end, samples of suspended particulate matter (SPM) were carried out using two different methodologies: the horizontal flow trap (portable traps) and the vertical flow trap (fixed traps). For the extraction of P, the sequential extraction method SEDEX was adopted, which allowed the extraction of five forms: P-Ex, P-Fe, P-Au, PDe and P-Org, in addition to P-Bio. In the Tucunduba river, Total-P concentrations ranged from 20.52 to 100.78 μmol.g-1, with predominance of the P-Fe fraction. In the Tamandaré River, concentrations ranged from 42.36 to 173.88 μmol.g-1 with P-Au predominance. Thus, it was possible to verify that the urban rivers Tucunduba and Tamandaré have high concentrations of P and its species. With these data, it is clear the need to deepen this type of study in these rivers and other urban rivers present in Belém, as well as the need for policies aimed at the recovery and preservation of these, in order to mitigate the problem involving phosphorus and restore the capacity ecosystems of these environments.
Acesso aberto (Open Access)
Evolução multitemporal (2010-2024) do canal de acesso do estuário do rio Amazonas (canal Norte - baía de Macapá - margem ocidental)
(Universidade Federal do Pará, 2025-02-27) SILVA, Eduardo Pantoja da; EL-ROBRINI, Maâmar; http://lattes.cnpq.br/5707365981163429; https://orcid.org/0000-0001-7850-1217
The Amazon River, the world’s largest by water volume, has an average discharge of approximately 209,000 m³/s and exhibits a semidiurnal tidal range that varies from 0.3 m to 4 m during spring tides. Its vast watershed profoundly shapes the geomorphology of the Amazon Basin, driving sedimentary processes and directly affecting navigability. The economic importance of navigation within its estuary contrasts sharply with the challenges posed by both natural and anthropogenic alterations, which compromise the long-term stability of the channel. This dissertation analyzes the geomorphological evolution of the Amazon River’s northern channel and Macapá Bay from 2010 to 2024. It assesses the impacts of sedimentary dynamics on navigability and port management. The research methodology encompassed the analysis of bathymetric data, 38 Sentinel-1 radar scenes (captured between 2016 and 2024) processed via the Google Earth Engine platform, and historical hydrological records. Bathymetric processing was carried out in SURFER using the kriging method, while spatial analyses were performed with geostatistical tools in Python and QGIS. This included the delineation of sandbanks and the calculation of modification areas to identify erosion and deposition patterns. The study area is highly dynamic, influenced by tidal forces, river discharge, and sedimentation. These interacting processes drive the formation and migration of sandbanks and unstable channels, which directly affect bed depth and navigational safety. The findings indicate a reduction in the northern channel’s average depth from 26 m to 22 m, along with a noticeable east-northeastward migration. This shift is evidenced by erosion along the left bank and simultaneous deposition on the right bank. Three-dimensional analysis revealed that while the bed morphology was relatively homogeneous in 2011, by 2024 it had become more compartmentalized, reflecting a rate of change of 0.307 m per year. The study also highlights significant variations in the spatial extent of emerged areas within Macapá Bay. During El Niño years (2016, 2018, 2023), average accretion reached 8,326.93 km², whereas La Niña years (2017, 2020, 2021, 2022) experienced average erosion of -13,941.27 km². Linear regression analysis produced an adjusted R² value of 0.163, indicating that hydrological variability and human activity influence the region’s sedimentary dynamics. The observed geomorphological changes directly affect waterway management and the Santana port complex, underscoring the need for effective strategies to ensure ongoing navigability. Remote sensing has proven invaluable for monitoring these dynamic transformations, offering strategic insights to enhance port infrastructure planning and ensure the long-term sustainability of navigation in the region. This research reinforces the necessity of continuous monitoring and integrated hydrodynamic planning to maintain navigational safety and logistical efficiency. The combined use of geoprocessing and bathymetric techniques enables more accurate planning and the implementation of measures to mitigate sedimentation impacts, thereby preserving the viability of inland waterway transport. Ultimately, the results provide essential support for managing navigation in the Amazon River’s northern channel, promoting enhanced efficiency and safety.
Acesso aberto (Open Access)
Evolução multitemporal da linha de costa (1972-2040) do município de Soure, Ilha do Marajó (Amazônia - Brasil)
(Universidade Federal do Pará, 2021-11-11) MENEZES, Rafael Alexandre Alves; EL-ROBRINI, Maâmar; http://lattes.cnpq.br/5707365981163429; https://orcid.org/0000-0001-7850-1217
Exogenous agents that act in the Coastal Zone (ZC) act as morphological modelers of the CoastLine (LC) and this action modifies the erosive and accretive scenario of the LC over time. To assess these temporal changes in the ZC, remote sensing (SR), from orbital remote sensors, is an opening that makes it possible to identify these variations, where the main objective around the world is the management and protection of these coastal areas. Thus, the present composition aims to present the evolution of the LC line during the period 1972-2020 (48 years) and estimate the evolution of the LC for the years 2030 and 2040 in the ZC of the Soure municipality, located in the northeastern part (NE) of the Marajó island (Pará-Eastern Amazon), inserted in the Pará Estuarine Coastal Zone (ZCEP), conditioned by the hydrodynamics of the South channel of the Amazon River and by the estuary of the Pará River. A set of 6 images from a time series of the satellite were acquired: Landsat 1 (MSS) from 1972 and 1994 (bands 7.6.5 and 5.4.3, respectively), Landsat 5 (TM) from 1985, 2004, 2009 ( bands 5.4.3), with a spatial resolution of 30m, and Landsat 8 (OLI) 2020 (bands 6.5.4.8), with a spatial resolution of 15 m after the fusion of band 8 (panchromatic), being obtained from the USGS (United States Geological Survey) site, all already georeferenced and geoprocessing techniques for: a) LC delimitation: where it was created from semi-automatic methods combined with manual methods, using the normalized water difference index (NDWI) technique; b) DSAS version 5.0 (v5.0), being used to compose the LC analysis hrough this tool: NSM, EPR and LRR, version v5 brings the Kalman Filter, which was used to calculate the future estimate in the LC for the years 2030 and 2040. As a result, it was identified that in sectors I and II (southern channel of the Amazon River), accretion predominates, in sector III (Maguari Cape) it is where it obtained the highest accretion rates, and in sector IV the accretion process predominates with a tendency erosive, sector V erosion predominates. These data are linked to the total number of 654 transects comprising an average distance of 214.4 m, where the mean retreat is indicated with a negative rate of - 179.5 m and a positive rate of 451.9 m. For the years 2030 and 2040, the trend is that this process will continue, where the greatest coastal retraction, around 271.46 m, will be in the Northeast (NE) (sector II), and a CL advance of 625.26 m in sector III.
Acesso aberto (Open Access)
Gestão de resíduos por atividades turísticas na área de preservação ambiental (APA) em ilha metropolitana da Amazônia
(Universidade Federal do Pará, 2025-02-27) ELLERES, Igor Diniz; MONTEIRO, Sury de Moura; http://lattes.cnpq.br/4309806566068586; HTTPS://ORCID.ORG/0000-0001-9449-7043; SAMPAIO, Dionisio de Souza; http://lattes.cnpq.br/2193736281754259; https://orcid.org/0000-0002-2688-6001
Solid waste management on Combu Island, in Belém (PA), reflects the logistical and structural challenges faced by Amazonian riverside communities in the context of growing urbanization and tourism. This study focused on waste management and the various stakeholders involved, who play a crucial role in the collection and disposal of discarded materials. Interviews and observations were conducted to understand the practices adopted by restaurants regarding waste disposal and the perceptions of waste pickers about the impact of this activity on the environment and their livelihood. The results indicated that although restaurants generate significant volumes of waste—around 4.8 tons per year—the lack of proper infrastructure, such as selective collection and regular transportation, leads to improper disposal. This issue is partially mitigated by the work of waste pickers, who collect recyclables such as glass bottles and plastics, turning them into a source of income. However, waste pickers face precarious working conditions, with low recognition and little integration into public policies or environmental education initiatives. The research also revealed that restaurant managers recognize the importance of improving their practices and developing them based on the Sustainable Development Goals (SDGs 14 and 15), but often encounter logistical difficulties and a lack of incentives or specific regulations. It is concluded that promoting integrated actions between restaurants, waste pickers, and public authorities, along with environmental education strategies, can enhance the efficiency of solid waste management, reduce socio-environmental impacts, and value the stakeholders involved.
Acesso aberto (Open Access)
Investigação da influência antrópica na concentração de nutrientes inorgânicos dissolvidos no entorno da cidade de Belém-PA
(Universidade Federal do Pará, 2022-08-30) PORTO, Yuri Paixão Santa Rosa; ROLLNIC, Marcelo; http://lattes.cnpq.br/6585442266149471; https://orcid.org/0000-0002-8601-1514
Water is one of the most important natural resources, especially in the Amazon context. The disorderly population increase and consequent mismanagement of this resource causes worrying environmental changes in terms of its quality. According to the National Sanitation Information System - SNIS, the northern region of the country treats about 22.0% of the sewage generated and in the Metropolitan Region of Belém, below the national average, with 11.3% of sewage collection. The study area encompasses Guajará Bay and adjacent areas such as the Guamá and Acará rivers. Water collections were carried out during the rainy season (May), in 4 sections divided into left bank (ME), middle (M) and right bank (MD) with surface and bottom collections, every 4 hours for 13 hours to analyze the entire tidal cycle. Parameters were analyzed in situ (Temperature, pH, Eh, electrical conductivity, turbidity, OD, %OD and total dissolved solids) and in the laboratory (Silicate, phosphate, nitrate and nitrite), in addition to determining the intensity, speed and direction of the current. with the aid of an ADCP to obtain the flow and calculate the nutrient flow. The study area has some more remote places with little or no human influence throughout its extension, and others with untreated domestic and industrial effluent discharge points. The objective of this work is to investigate a possible anthropic contribution in the flow of dissolved inorganic nutrients from the water bodies that bathe the city of Belém-PA and surroundings. The Guamá River near the “alça viária” showed the lowest values of dissolved inorganic nutrients, unlike the Acará River which, despite its geographical distance from the RMB, showed the highest values of nutrient concentration. The mouth of the Guamá river had higher nutrient values on its right bank and the Guajará bay in its central portion, due to the influence of domestic and industrial waste. The Guamá river near the “alça viária” is relatively preserved, with a low concentration of dissolved inorganic nutrients, increasing only near its mouth, while the Acará presented higher values mainly due to the intense agricultural activity in the surroundings of its basin. The Guajará Bay, despite receiving discharges from the Acará and Guamá rivers, has lower nutrient values than the two locations, demonstrating its capacity for self-purification and dilution.
Acesso aberto (Open Access)
Modelagem tridimensional da hidrodinâmica e transporte sedimentar de um lago amazônico urbano
(Universidade Federal do Pará, 2025-04-17) CALLADO, Marco Antônio Vieira; ROLLNIC, Marcelo; http://lattes.cnpq.br/6585442266149471; https://orcid.org/0000-0002-8601-1514
Lakes are critical environments for sustaining human well-being, as they regulate local climate conditions, supply potable water, and underpin a wide range of ecosystem services. The continuous monitoring of these systems is essential for elucidating their metabolic processes and for informing effective management strategies for natural resources. This study aims to develop an environmental diagnosis and prognosis for a shallow Amazonian lake located in an urban area—Lago Água Preta—through the application of a three-dimensional numerical model of hydrodynamics and sediment transport. Numerical simulations were performed using the Delft3D-FLOW model, encompassing the region’s seasonal periods: wet and dry seasons. The simulations were driven meteorological variables and physical parameters of the lake, such as air temperature, humidity, cloud cover, solar radiation, bathymetry, water temperature, current velocity, and the inflow/outflow rates. This comprehensive dataset allowed for the construction of a computational environment capable of accurately representing the hydro-sedimentary processes within the lake Model calibration was performed using a one-month time series of water temperature from February (wet season), while validation was carried out with current data and vertical temperature profiles over four months (December, February, April, and June). The simulations presented good statistical indicators, demonstrating the model's reliability. The greatest discrepancies between simulation and observation occurred at points closer to the urban center. These differences are associated with the influence of anthropogenic activities, such as the discharge of domestic effluents, or with the narrow morphology of the lake in these areas, which can generate thermal shadow zones. The analysis of circulation and temperature patterns between seasonal periods revealed relatively small differences. Notably, there was an average increase of up to 2 °C in water temperature and approximately 0.02 m/s in current velocity during the warmer period. The most significant differences in average temperature occurred in the lake's daily cycle, varying by about 3°C, with a maximum variation of up to 10°C. Since the lake is fed by an artificial water inflow, this inflow is characterized by an intense discharge with a high sediment load. As it is a shallow lake with a maximum depth of up to 4 meters, this discharge is capable of influencing the lake’s entire metabolism by promoting the resuspension of bottom sediments and redistributing nutrients into the water column. Upon entering the lake, the inflow currents are rapidly decelerated, intensifying sedimentation near the inflow point. This process increases water turbidity and alters the local biotic dynamics, resulting in an environment dominated by phytoplankton and prone to eutrophication processes, which consequently reduce water quality. Therefore, based on the diagnosis provided by the modeling of Lago Água Preta, this study highlights the need for ongoing monitoring and control of anthropogenic influences to prevent the progressive degradation of the lake's metabolism. It also underscores the importance of lakes in general, especially when located in urban contexts.
Acesso aberto (Open Access)
Monitoramento meteorológico e hidrodinâmico de um ambiente lêntico em uma região metropolitana amazônica
(Universidade Federal do Pará, 2025-04-25) GOMES, João Vitor da Silva; ROSÁRIO, Renan Peixoto; http://lattes.cnpq.br/8003860457518342; https://orcid.org/0000-0003-2913-0514
The increasing urbanization and the resulting pressure on water resources have intensified the need to monitor and manage aquatic ecosystems. The Utinga State Park, located in Belém, Pará, is home to an important lake that plays a crucial role in supplying water to the region. However, the lack of urban planning and the disorderly population growth have jeopardized both the quality and quantity of this water resource. In light of this scenario, the present study aimed to evaluate the hydrodynamic and meteorological conditions of Água Preta Lake, with the goal of contributing to its conservation and sustainable management. Meteorological parameters were measured using a weather station over a 12-month period, with data made available at 60- minute intervals. Hydrodynamic data were collected using instruments such as the ADCP, which measures current intensity and direction at 50 cm intervals along the water column; an electromagnetic current meter, used for 48-hour measurements during both dry and rainy seasons to validate the lake's hydrodynamic patterns; and a CTD profiler, which measured the vertical temperature profile. Additionally, levelogger pressure sensors were deployed at strategic locations. After analysis, it was found that the lake's current velocity is low. Meteorological factors remained within the ranges reported by other authors, confirming the consistency of the collected data with previous studies. The hydrodynamic analysis revealed restricted circulation patterns, with limited water movement, especially near the bottom. The main driving force of the system is the operation of pumps that supply the lake with water from the Guamá River. Surface water movement is also limited, as wind speeds are low, hindering circulation in this environment. These results highlight the importance of continuous monitoring for the efficient management of the lake, especially in the context of growing environmental pressure caused by unplanned urbanization. The information obtained provides a solid foundation for future conservation actions, contributing to the preservation of biodiversity and the sustainability of the region's water supply.
Acesso aberto (Open Access)
Morfodinâmica de praias estuarinas da vila de Jubim (ilha do Marajó-Pa)
(Universidade Federal do Pará, 2025-04-25) RODRIGUES, Mayara de Souza; RANIERI, Leilanhe Almeida; http://lattes.cnpq.br/3129401501809850; https://orcid.org/0000-0002-9870-4879
The Brazilian Amazon Coastal Zone (states of Amapá, Pará and Maranhão) has environmental characteristics such as a humid tropical climate (high temperatures, low thermal and rainfall variation) and important oceanographic conditions (hyper to mesotidal), in addition to extensive mangroves and sandy beaches, including estuarine beaches. These are vulnerable to seasonal changes in river discharge, in addition to current climate change, the consequent rise in sea level and the resulting coastal erosion, which causes negative consequences for the goods and services originating from this coastal ecosystem. The objective of this study was to analyze the changes in the morphology and sediment dynamics of the estuarine beaches of Jubim and adjacent areas, during a complete seasonal cycle (March 2023 to March 2024). Jubim is a district located in the municipality of Salvaterra, State of Pará, on the east bank of Marajó Island, under oceanographic conditions of the Pará River estuary. Data collection was carried out on four specific beaches, namely: Salazar Beach, Meninas Beach, Baleia Beach and Curuanã Beach. To characterize the morphodynamic state of the beaches, the slope (β) and relative tidal variation (RTR) parameters, derived from the treatment of physical and topographic data (beach profiles), were used as reference. For granulometric analysis, surface sediment samples were subjected to dry sieving in order to obtain the average size, grain selection and sedimentary balance of the beaches. The results showed that the beaches of the village of Jubim have sedimentation ranging from medium to fine sand 1 ɸ and 2 ɸ, with moderately well-sorted grains. The beaches presented quite varied morphometric parameters: topographic elevation from 5.6 m to 2.7 m, and beach width ranging from 79 m to 550 m, thus classifying them into dissipative to intermediate morphodynamic stages (beach slope from 0.2° to 2.6°), with tidal dominance (RTR = 44). The seasonal sedimentary variation was both positive and negative, indicating that the variability index alternate along the beaches and climatic seasons, showing both erosive and depositional tendencies. Erosive processes were observed mainly in the rainy season and greater sedimentary deposition in the dry season. The morphological behavior of the beaches studied on the eastern shore of Marajó Island is directly influenced by estuarine hydrodynamics, where the distinct sedimentary changes are due to the interation that hidrodynamics with the differentiated geology along the coast, and the respective material that constitutes the substrate of the beaches and backwaters.
Acesso aberto (Open Access)
Mudanças morfológicas em praias da costa Leste da ilha do Marajó e os níveis de vulnerabilidade à erosão
(Universidade Federal do Pará, 2021-06-29) SOUSA, Maria Bárbara Pereira de; RANIERI, Leilanhe Almeida; http://lattes.cnpq.br/3129401501809850; https://orcid.org/0000-0002-9870-4879
The coastal zone is a transition area between the sea and the continent, being one of the most vulnerable geographic spaces on the planet. In view of this, the assessment of morphological changes and coastal vulnerability to erosion is essential, as it contributes to the planning of protective and mitigating actions against impacts that occur on the environment, whether natural or anthropic. Thus, the work aims to verify the morphological changes in beaches on the east coast of Ilha de Marajó/PA and their levels of vulnerability to erosion at different time scales. For this purpose, two field campaigns (dry and rainy seasons) were carried out at Barra Velha beach (municipality of Soure) and Praia Grande (municipality of Salvaterra). The methodology consisted of a semi-quantitative analysis, determined by parameters of human and natural occupation evaluated on the beaches. Remote sensing techniques (medium period data) and in situ data collection (short period data) were used. According to the results obtained, Barra Velha beach was classified as dissipative in the two periods studied and most profiles topographic showed an erosive trend from the dry to the rainy period. Praia Grande showed behavior of intermediate to reflective beaches in both the dry and rainy seasons. The sedimentary accretion phase of this beach occurred during the rainy season, reflecting an atypical pattern for beach morphodynamics. Barra Velha beach exhibited moderate erosion vulnerability in the northwest sector and high vulnerability in the southeast sector, mainly due to the high erosion rate over the 16 years studied. Praia Grande, on the other hand, presented a moderate degree of vulnerability to erosion, being considered a more stable beach, combined with coastal protection works. On both beaches, the coastal risk was low due to the low level of occupation close to the coastline. It is believed that the results of this research can contribute to future studies on the theme of vulnerability to erosion in areas that are little or very anthropized and, for possible actions of coastal management in the Amazon region, considering their environmental particularities.
Acesso aberto (Open Access)
Ninhos azuis: o primeiro registro do uso de resíduos plásticos na nidificação de aves na Costa Amazônica, Brasil
(Universidade Federal do Pará, 2024-06-21) LOPES, Adrielle Caroline; MARTINELLI FILHO, José Eduardo; http://lattes.cnpq.br/2080628833884538
While extensive research has been conducted on the effects of plastic on marine ecosystems, a gap exists in studies related to terrestrial biota. Research indicates that certain terrestrial animal taxa, such as birds, may be more prone to incorporating plastic debris into their habitats. This study focused on the interaction between Psarocolius decumanus, a common bird species in the Amazon region, and plastic use during nesting. Non-invasive techniques were employed to minimize the impact on nests and bird life. Fallen and abandoned nests were collected, while active nests were photographed and recorded with GPS for comparison between different collection areas. In the laboratory, the nests were analyzed, weighed, and measured for a detailed analysis of plastic waste. The analysis revealed significant differences in plastic width and mass in nests between collection sites. The results also revealed a widespread presence of plastic in the nests: 24 out of 36 presented plastics in their composition, with the highest proportion found in the mangrove area. All mangrove nests contained plastic, with a proportion between 15.4 and 97.9% of dry weight. In the clearing near Farol beach, only six of the 17 nests contained plastic, with a much lower proportion relative to the dry weight of each nest (0 to 0.2%). On fishing village, 90% of the nests presented plastics, with a proportion ranging from 1.4 to 95.5%. Plastic fibers and cords were the most common materials. The predominant color was blue, suggesting a possible preference for this color by the bird or reflecting the prevalence of certain types of plastics in the region. The analyses revealed variations in the incidence of plastic in different areas, indicating an influence of the availability of debris in the surrounding environment. The presence of plastic in nests can have adverse consequences for birds and their young, including impacts on feeding, reproduction, and mortality. The study also monitored nest activity, revealing patterns in the number of active nests in each location. This highlights the importance of continuous monitoring of the presence of debris in nests as a potential bioindicator of environmental pollution levels. This pioneering study provides unprecedented data on pollution patterns and the environmental impacts associated with the presence of plastic debris in the nests of terrestrial birds in the Amazon rainforest.