https://repositorio.ufra.edu.br/jspui/handle/123456789/60 Thu, 23 Apr 2026 18:30:54 GMT 2026-04-23T18:30:54Z https://repositorio.ufra.edu.br/jspui/handle/riufra/2865 Título: Fogo e a organização funcional da comunidade de árvores: implicações para a resiliência da floresta na Resex Tapajós-Arapiuns Autor(es): SILVA, Danilo Souza da Abstract: Tropical forests play a fundamental role in global sustainability. In this context, fire emerges as a threat because it affects not only the species vulnerable to fire, but also the taxonomic and functional compositions of communities, limiting the maintenance of biodiversity and provision of essential ecosystem services. This study aimed to understand how tree vegetation responds to fire, through functional attributes, and what are the implications for Amazonian forest resilience. The study compared the tree component of unburned forest areas and forests that burned in 2015 and in 2017, in the Tapajós-Arapiuns Extractive Reserve, located in western Pará State, Brazil. The most abundant species (above 50% of total abundance), which constitute the canopy and understory of the tree component, had 12 functional attributes evaluated (e.g., bark thickness, regrowth capacity, wood density). The results showed that species richness differs between the two forest types and suggest that the understory of burned forests responds to fire events through a change in species composition, which highlights species simplification for this stratum. We also observed that functional changes in burned forest arise mainly from attributes of indirect effect to fire, such as dispersal and pollination syndromes, and that there are changes in the functional composition of communities when analyzed at the individual level for both the canopy and the understory. Our study indicates that fire events have caused a negative effect on the tree component of Amazonian humid tropical forests, and that their action has caused functional changes in species in burned forest areas. Furthermore, the effects of fire can vary according to forest stratum. The changes observed as effects of fire may have important consequences for forest dynamics and intensifying studies in this area is essential in the Amazon. Thu, 16 Apr 2026 00:00:00 GMT https://repositorio.ufra.edu.br/jspui/handle/riufra/2865 2026-04-16T00:00:00Z https://repositorio.ufra.edu.br/jspui/handle/riufra/2864 Título: Sistemática de Hydrochorea Barneby & J.W.Grimes ( Leguminose, Mimosoideae) Autor(es): SOARES, Marcos Vinicius Batista Abstract: Hydrochorea is a Neotropical genus distributed in northern South America, occurring only in the Amazon and Cerrado domains. Belong the tribe Ingeae, its species have suffered several generic replacements throughout its history. Hydrochorea belongs to the "Alliance-Abarema" informal clade that also has the Abarema and Balizia genus, mainly differentiated by the type of fruit. The genus Hydrochorea is characterized by drupaceous loment fruit characteristic within the tribe, and rare in Mimosoideae. There are still many problems regarding the constituency of taxa currently subordinate to Hydrochorea. In this context, this paper aims to conduct the taxonomic study and the first attempt of the phylogenetic of Hydrochorea in order to show their infrageneric limits and the circumscription of their species as well as the relationships within the "Alliance-Abarema". In this work the "Alliance-Abarema" is strongly supported for two markers with Hydrochorea and Balizia in a polytomy, which together form the sister group of Abarema. Although Hydrochorea group is not resolved as monophyletic, length and support of the branches of this group is not high and the paraphyly of Hydrochorea regarding Balizia is not conclusive. New markers and population approaches should be tested to improve the resolution of this clade and clarify the relationship between these two genus. Hydrochorea is here circumscribed with five species and three varieties. Describes two new species and two lectotipifications are presented. Number of leaf jugae, prominent secondary veins, type and shape of the rachis extrafloral nectaries, flower bud, the shape of calyx in central flower and the presence or absence of this trichomes, were the character used in the separation of species. Taха grow predominantly in margin of rivers, floodplain forests and flooded forest, and areas where the seed can reach by dispersing the rivers. Further studies should be directed to countries like Venezuela, Bolivia, Guyana and Suriname and Brazil, in order to understand the ecology of these species in their natural habitat. Mon, 13 Apr 2026 00:00:00 GMT https://repositorio.ufra.edu.br/jspui/handle/riufra/2864 2026-04-13T00:00:00Z https://repositorio.ufra.edu.br/jspui/handle/riufra/2850 Título: Secagem de frutos e fazes de maturação de sementes de Pentaclethra macroloba (Willd.) Kuntze (Lguminosae, Caesalpinioideae) provenientes de várzea alta e baixa. Autor(es): ARAÚJO, Maria Elanne da Silva Abstract: Pentaclethra macroloba (Willd.) Kuntze seeds exhibit heterogeneous maturation and are dispersed with high water content, making them more susceptible to deterioration and difficult to harvest. Therefore, the study aimed to evaluate the influence of drying on the physiological quality of P. macroloba seeds collected in different floodplain conditions and maturation stages. The fruits were collected in high and low floodplain environments, in three maturation stages (P1: green; P2: yellowish-green; P3: black), and were subjected to artificial drying at 23°C for seven days. The seeds were analyzed for water content, viability and vigor. The results showed that the seeds of stage 3 presented the greatest physiological potential and vigor, followed by stage 2, with superior performance in the seeds from the low floodplain. Seed mortality was not influenced by drying. In addition, drying promoted greater uniformity in the germination process. It is concluded that P. macroloba seeds can be harvested in phase 3, in a low-lying floodplain environment, ensuring the maintenance of physiological quality. These findings are important for management and conservation practices of the species, contributing to sustainable use and production of high-quality seedlings. Fri, 13 Mar 2026 00:00:00 GMT https://repositorio.ufra.edu.br/jspui/handle/riufra/2850 2026-03-13T00:00:00Z https://repositorio.ufra.edu.br/jspui/handle/riufra/2834 Título: Taxonomia de Ochnaceae DC. (Malpighiales) do Estado do Maranhão, Brasil. Autor(es): CALDAS, Mayara Dias Abstract: The state of Maranhão has a unique vegetation structure, which, as an ecotone region, tends to contain species from both the Amazon and Cerrado domains. Although it has many published floristic surveys, especially in the coastal zone, the state still lacks more in-depth taxonomic treatments of specific taxa, such as Ochnaceae. Ochnaceae belongs to the order Malpighiales and has approximately 642 species distributed in 37 genera. Of the 210 species occurring in Brazil, only 16 have been recorded in Maranhão to date distributed in two genera: Ouratea Aubl., with 13 representatives, and Sauvagesia L., with three. Aiming to confirm the occurrence of these species and gather new data on the taxonomy of the family in the state, we present in this work the taxonomic treatment of Ochnaceae from the state of Maranhão, based on collecting expeditions on São Luís Island, campinaranas environment in the extreme west of the state, part of the Legal Amazon in the Gurupi Biological Reserve, and analysis of the herbaria collections BMA, CCAA, HABIT, MAR, and SLUI in Maranhão, IAN and MG in Pará, CEN and UB in the Federal District, in addition to specimens available in virtual collections. As a result, six new records were identified based on the Flora e Funga do Brasil: three in Ouratea—O. parvifolia (A.St.-Hil.) Engl., O. salicifolia (A.St.-Hil. & Tul.) Engl., O. spectabilis (Mart.) Engl.—and three in Sauvagesia—S. deflexifolia Gardner, S. sprengelii A.St.-Hil. and S. tenella Lam., as well as one new synonym. This volume also reports on Dr. Emil Snethlage's travel in Maranhão and the importance of his collections for Ochnaceae. The new records and nomenclatural changes demonstrate the importance of taxonomic work even in locations with good sampling, especially when involving fieldwork. This work is relevant for recognizing local flora, updating species distribution data in the state, and for providing information that can support future biogeographic, molecular, and ecological research. Tue, 10 Mar 2026 00:00:00 GMT https://repositorio.ufra.edu.br/jspui/handle/riufra/2834 2026-03-10T00:00:00Z