Navegando por Assunto "Navigation"

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Acesso aberto (Open Access)
Aonde a vista alcança: conhecimento tradicional e geolocalização como complemento na navegação e regiões pouco cartografados
(Universidade Federal do Pará, 2017-09) ANDRADE, Carlos Eduardo Rangel de; FERNANDES, José Guilherme dos Santos; SMITH JÚNIOR, Francisco Pereira
This article presents a discussion about the peculiarities of fishing in the salty region in the northeast of the state of Pará. It presents the traditional methods of fishing used with characteristics of a region and how these knowledge contribute to the theoretical knowledge. As a way of reflection we used the studies of Fernandes and Fernandes (2015) to understand the knowledge and knowledge of traditional peoples, as well as Carvalho (2007) to discuss topics related to culture.
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)
A (in)viabilidade da navegação comercial pelo Araguaia: um século de desafios
(Universidade Federal do Pará, 2017-06) BATISTA, Alcelides
The objective of this article is to present a brief historical context of river navigation along the Araguaia waters, considering the political and administrative actions taken in the late eighteenth century and throughout the nineteenth century in order to carry out communication and interprovincial trade through Goiás, Pará. From the historical context, it intends to also demonstrate how existing natural accidents have become limiting factors to the implementation of river navigation. Therefore, we present Traveler reports, descriptive studies and memories of the period that registered the conditions of navigability and natural barriers that prevented or limited the navigation along the Araguaia river.