https://repositorio.ufra.edu.br/jspui/handle/123456789/22 Programa de Pós-Graduação em Aquicultura e Recursos Aquáticos Tropicais 2026-08-22T16:51:03Z https://repositorio.ufra.edu.br/jspui/handle/riufra/2896 Título: Zooplâncton Gelatinoso no Atlântico Tropical Oeste: distribuição, estrutura populacional e ênfase em Pyrosoma Autor(es): OLIVEIRA, Ludmilla Karina Lima Abstract: Planktonic tunicates of the genus Pyrosoma are part of the gelatinous zooplankton and play a relevant role in the transfer of energy and matter in the ocean, yet they remain underestimated and understudied in the Tropical Atlantic, partly due to their fragility and the limitations of traditional sampling methods. Hydromedusae, another component of the gelatinous zooplankton, shared this history of scientific neglect, with taxonomic records still scarce for the Brazilian equatorial margin. This dissertation investigated, in two complementary chapters, the distribution and ecology of these groups in the Western Tropical Atlantic. Chapter II analyzed the spatial (horizontal and vertical) and temporal (day–night) structure of the genus Pyrosoma in the North and Northeast regions of Brazil, characterizing the physical and chemical variables of the water column (temperature, salinity, dissolved oxygen, turbidity, and fluorescence) and correlating them with colony density (CPUE; colonies·hour⁻¹) and size structure (length in mm). Data were obtained from three oceanographic surveys conducted aboard the R/V Antea , ABRAÇOS I (2015), ABRAÇOS II (2017), and AMAZOMIX (2021), using diurnal and nocturnal oblique trawls with a mesopelagic micronekton net. Analyses included comparisons among regions, depth layers, and time periods (Kruskal–Wallis, Wilcoxon), Spearman correlation, distance-based Redundancy Analysis (db-RDA), and Generalized Linear Models with a Gamma distribution. Chapter III reported the first records of the hydromedusae Leuckartiara octona and Calycopsis papillata (Hydrozoa: Filifera) for the Brazilian Equatorial Margin, based on samples collected during the AMAZOMIX survey. Morphological descriptions of the specimens, density data, vertical distribution, and the environmental conditions associated with the occurrence of each species in relation to the Amazon River plume were presented. Together, both chapters contributed to expanding the knowledge of gelatinous zooplankton diversity and ecology in the Western Tropical Atlantic, highlighting how regional physical-oceanographic gradients, particularly the contrast between the Amazon plume and the oceanic conditions of Northeast Brazil, modulate the distribution, abundance, and population structure of the studied groups. 2026-01-01T00:00:00Z https://repositorio.ufra.edu.br/jspui/handle/riufra/2895 Título: Desvendando o comércio de peixes no nordeste paraense. Autor(es): FARIAS, Tiago Sousa de Abstract: The Brazilian Amazon Coast (LAB) has a high biodiversity of aquatic organisms, especially fish. Local fishing activity has an impact on aquatic resources, whether they are targeted by fishing methods (accompanying fauna), and is a global threat to species, especially those threatened with extinction, such as sharks and rays. Even though fish are a nutritionally, economically, and culturally important resource for the Brazilian Amazon, there is a recurring lack of data on the catch and composition of the species sold. Especially in cases where a) more than one species is sold under a single popular name; b) the fish species have high morphological similarity; c) the fish have low commercial value; and d) the fish are sold uncharacterized (without heads, fins, etc.) in the markets, which creates difficulties in identifying and measuring them. The research problem lies in the lack of data on the dynamics of fish marketing in the fish markets of Bragança, Capanema, Castanhal, Salinópolis, and São João de Pirabas. Due to the recurring lack of data on these bycatches, a scientometric survey carried out on the Scopus, Scielo, Web of Science and Google Scholar databases on the shark and ray bycatch fauna resulted in 28 scientific articles published in 21 joumals. We list 28 species of sharks and 14 species of rays cited as being caught in these articles. Of the 40 fish retailers interviewed, the majority were aged between 51 and 60 (32.5%) and between 31 and 40 (22.5%). It can be seen that the fish retail outlets are supplied by middlemen or directly by fishermen firom various fishing locations. For both the dry and rainy seasons, 17 fish were cited as the most frequent. Among the 32 most frequent fish throughout the year, "Gó" (22.4%) and "Bandeirado" (9.2%) were the most frequent. The presence of 43 species of commercialized bony fish was recorded, of which only three species were identified to genus levei due to their high morphological similarity. On the other hand, cartilaginous fish were identified at a specific levei in only two species due to the way they are sold, such as carcasses or types of cut, which makes it difficult to diagnose the species. We also identified two cases of homonymy, one of synonymy, and 12 totally local commercial names. We noticed a predominance of coastal fish sold in coastal towns (71%) and non-coastal towns (66.6%), but an increase in freshwater fish in non-coastal towns due to their case of logistics. 2025-07-15T00:00:00Z https://repositorio.ufra.edu.br/jspui/handle/riufra/2891 Título: Avaliação das águas superficiais da bacia hidrográfica do baixo tocantis, Pará, Brasil: Um panorama no espaço e no tempo Autor(es): MELO http://lattes.cnpq.br/3542869559542094, Adriana da cruz; banca 1 ALVES JÚNIOR http://lattes.cnpq.br/2566643607928091, Flavio de Almeida; banca 2 LIMA http://lattes.cnpq.br/8021186707342335, Mauricio Willians de https://orcid.org/0000-0001-9092-8731; banca 3 CHAGAS http://lattes.cnpq.br/9393899936340805, Rafael Anaisce das https://orcid.org/0000-0002-1555-6154 Abstract: Preserving water quality is essential for human survival and environmental conservation. Despite Brazil possessing the largest amount of freshwater in the world, it faces a water crisis throughout its territory due to problems such as lack of sanitation, pollution from agriculture, and lack of water reuse. The Tocantins-Araguaia River basin, the second largest in the country, encompasses a vast area with 430 municipalities distributed across the states of Pará, Maranhão, Tocantins, Goiás, and Mato Grosso. This study focuses on the Lower Tocantins region in northeastern Pará, where abiotic and biotic water parameters will be evaluated to understand the environmental dynamics. Factors such as land use, anthropogenic actions, and periods of intense rainfall influence water quality, increasing turbidity and nutrient levels, such as nitrogen and phosphorus, which can lead to eutrophication. CONAMA Resolution 357/2005 is a fundamental instrument for monitoring water quality standards in Brazil, contributing to the sustainable use of this vital resource. This study aimed to evaluate environmental parameters, calculate the Trophic State Index (TSI), and analyze the influence of seasonality, focusing on eleven points distributed across seven municipalities in Pará state, in order to support the planning of water preservation actions in the region. The results show the influence of seasonality on water quality, with higher values of electrical conductivity in the less rainy period (79 μS cm⁻¹) compared to the rainy period (65 μS cm⁻¹), indicating a higher concentration of dissolved ions. Chlorophyll a was also higher in the less rainy period (12.2 μg L⁻¹) compared to the rainy period (9.8 μg L⁻¹), suggesting a greater supply of nutrients. Turbidity was higher during the less rainy period (97 NTU), while dissolved oxygen remained close to 6.4 mg L⁻¹ in both periods. The Trophic State Index ranged from 51.32 to 52.11, indicating a mesotrophic condition and the influence of seasonality on the limnological dynamics of the region. 2026-05-22T00:00:00Z https://repositorio.ufra.edu.br/jspui/handle/riufra/2887 Título: Decifrando os desembarques de grandes bagres migradores: Como as características operacionais e sazonais moldam a pesca no estuário Amazônico? Autor(es): COSTA, Izabelle Tavares da Abstract: Fishery resources play an important role in the global economy. In the Amazon, fishing is a traditional and economically significant activity that provides both income and food security. Amazonian fish production is dominated by large migratory catfish species, such as piramutaba, dourada, and filhote, which depend on extensive migrations to complete their life cycle. Analyzing fishery activity data is an indirect approach to assessing fish populations. This study aimed to investigate the operational, spatial, and temporal characteristics that influence the occurrence and intensity of catches of B. rousseauxii, B. vaillantii, and B. filamentosum at the mouth of the Amazon River. Using advanced statistical tools, we evaluated the relationship between the CPUE of B. rousseauxii, B. vaillantii, and B. filamentosum as a function of seasonality and fishery operational characteristics, such as fishing area and vessel fishing power in the Amazon estuary. To account for zero-inflated data, a Hurdle model was applied, allowing a two-part structure: a binary component indicating the absence of CPUE and a continuous component modeling positive CPUE values. The CPUE of dourada is influenced by vessel classification and by the interaction between area and period. The CPUE of piramutaba varies with fishing area and period, and the effect of the period changes depending on the area. The CPUE of filhote varies with vessel type, area, and period, and the effect of the period also changes according to the area. These findings underscore the need for management strategies that incorporate the seasonality and spatial heterogeneity of fishing in the Amazon estuary. 2026-01-01T00:00:00Z