DSpace Coleção: Mestrado

Restauração de ecossistemas ripários degradados pós-mineração de estanho na Amazônia Central: Dinâmica ecológica e indicadores de restauração.

2026-03-25T00:00:00Z

Título: Restauração de ecossistemas ripários degradados pós-mineração de estanho na Amazônia Central: Dinâmica ecológica e indicadores de restauração. Autor(es): PEREIRA, Marcele Farias Abstract: The The restoration of riparian forests degraded by mining represents a significant ecological challenge due to the structural, compositional, and functional alterations that affect these ecosystems. In this context, this study aimed to analyze the ecological indicators used to monitor the restoration of riparian forests in mined areas and to evaluate the vegetation dynamics in riparian ecosystems undergoing active restoration following tin mining in the Central Amazon.Thus, this dissertation was divided into two chapters. The first chapter consisted of a bibliometric analysis of global scientific production published between 1990 and 2024, based on 141 articles from the databases Science Direct, JSTOR, SciELO, SpringerLink, and Wiley Online Library, investigating temporal trends, geographic distribution, restoration methods, and categories of ecological indicators for riparian forests. The results revealed a significant increase in publications starting in 2020, with a predominance of functional indicators and a progressive increase in the integration of compositional, structural, and functional indicators, indicating the consolidation of multidimensional approaches in restoration monitoring.The second chapter evaluated the structural and floristic dynamics of vegetation in eight riparian ecosystems undergoing restoration through seedling planting, with ages ranging from 2.5 to 10 years, compared with a mature reference forest, totaling 58 permanent plots. An increase in diversity and floristic differentiation was observed along the chronosequence, with a predominance of pioneer species in the early stages and greater diversity in intermediate ecosystems. The species Clitoria fairchildiana stood out due to its high increment in diameter and height, evidencing the success of active restoration.The integration of information from the bibliometric analysis and the empirical study demonstrated advances in the use of ecological indicators and confirms the effectiveness of active restoration in recovering structural and floristic attributes, contributing to the improvement of monitoring and restoration strategies for riparian ecosystems degraded by mining.

Capacidade produtiva em floresta de planalto no Baixo Tapajós, Amazônia Oriental.

2026-01-17T00:00:00Z

Título: Capacidade produtiva em floresta de planalto no Baixo Tapajós, Amazônia Oriental. Autor(es): SANTOS, Maria Kelliane Valentim dos Abstract: The classification and mapping of sites, together with all the data present in the management plan are important tools for planning forest management. Having this information it is possible to infer their quality with regard to production capacity and stock related a given product. This study aimed to identify classes of productive capacity of the forest and to valuate commercial forest products occurring in the Zone for management of Non Timber Forest products of the Tapajós National Forest covering an area of 36.925,33 hectares. A total of 94 plots of 30 x 250 m, were randomly placed, which summed up a total sampled area of 70,5 ha. The size classes (CT): CT, - 10 em < DAP <25 cm in subplot 30 m x 50 m; CT, - 25 em < DAP < 50 em subplot of 30 m x 100 m; and CT3 - DAP > 50 cm in the plot of 30 m x 250 m were inventoried in each plot. The Cluster analysis was performed using the software MATLAB. For the valuation of the forest products, with a market value, the 50 most important species as the importance value were considered, by selecting trees with DAP > 50 em (timber) and DAP > 25 cm (non-timber), applying if the criteria of maintenance and felling, in accordance with the standards of environmental agencies, and using two scenarios that the maximum intensity of logging (IMC) of 30 m? ha” and the real potential of forest harvesting. The valuation of forest timber products was based on wood price adjusted by the Forest Service in 2013 for the concession contract and the value of non timber forest products (NTFPs) was obtained in fairs of Santarém-PA and Coomflona (Cooperative mixed of the Tapajos National forest), considering the price paid in the forest. Through cluster analysis identified two forest sites valued, respecting the IMC presented an estimated R $ 216.209,26 for the site IT and R $ 179.468,00 for site II per work unit (UT = 100 ha), and when it was not considered the IMC, the site I also presented higher value, where the difference was R$ 73.482,53. The valuation of forest (timber and non-timber) was estimated at R $ 218.939,26 by UT for the site T and R $ 186.377,00 for site II, considering the value of wood products when estimated based on the IMC, and R $ 290.151,42 and US $ 220.826,19 for UT to sites 1 and II, respectively, regardless of IMC. The forest management zone Non Timber presented low stock of NTFPs and high stock of commercial timber, especially Manilkara huberi, Hymenaea courbaril and Handroanthus impetiginosus. The two sites showed a potential for timber production higher than 30 m? h".

Avaliação da identificação botânica de árvores, em planos de manejo florestal no estado do Mato Grosso.

2026-02-01T00:00:00Z

Título: Avaliação da identificação botânica de árvores, em planos de manejo florestal no estado do Mato Grosso. Autor(es): SILVA, Elvis Rabelo da Abstract: The reliability of taxonomic identification in forest inventories is a key component for estimating stock by species and ensuring the traceability of harvested material in timber management operations in the southern Amazon. In this study, we examined the consistency of botanical identification of commercially important trees in operations in northern Mato Grosso State by comparing, on an individual-by-individual basis, the scientific name recorded in the inventory with the identification validated by botanical collections and taxonomic confirmation in a herbarium. Consistency was quantified at the species, genus, and family levels using agreement and performance metrics, including accuracy with bootstrap confidence intervals and Cohen’s κ coefficient, as well as the classification of errors when specific discrepancies occurred (same genus, same family, or different family). The consistency of the naming process was also evaluated in two stages (assignment of the common name and its conversion to the scientific name), along with the concentration of risk by sample substrate and volume. The results indicated moderate agreement at the species level (52.1%), contrasting with high agreement at the genus level (88.5%) and near-total agreement at the family level (99.5%). The κ coefficient confirmed this gradient, with κ = 0.5 at the species level and κ = 0.88 at the genus level. Among individuals with species-level errors, 76.1% remained in the same genus, 22.8% in the same family, and only 1.1% involved a change between families, evidencing Among individuals with species-level errors, 76.1% remained in the same genus, 22.8% in the same family, and only 1.1% involved a change between families, indicating that most inconsistencies result from “subtle” substitutions between closely related species. The distribution across agreement ranges reinforced this pattern: 52.1% of records showed complete agreement (100%), 36.5% showed agreement restricted to the genus (66%), 10.9% showed agreement restricted to the family (33%), and 0.5% showed complete disagreement (0%). In the evaluation of the naming process, high consistency of the common name was observed when compared to regional references (88.0%), but a reduction in the conversion of common names to scientific binomial names (52.1%), indicating that a substantial portion of the error is introduced by name-matching lists and documentary procedures that associate specific scientific names with vernacular labels that are often aggregative. Volume-weighted accuracy (71.2%) was higher than unweighted accuracy, but showed a significant volume associated with specific incorrect attributions and a concentration of risk in a few common names. Botanical identification in 100% inventories demonstrates robustness at broad taxonomic levels but significant limitations at the specific level, with errors systematically concentrated in taxonomic complexes and in highly recurrent common names. The findings support the adoption of targeted mitigation measures, including the local calibration of reference lists, the standardization of diagnostic criteria, and sample validation using vouchers that prioritize critical markers to reduce uncertainty and strengthen the technical basis for disease control.

Estoque de carbono orgânico no solo sob diferentes usos da terra na Amazônia oriental.

2026-02-26T00:00:00Z

Título: Estoque de carbono orgânico no solo sob diferentes usos da terra na Amazônia oriental. Autor(es): SOUZA, Adrielly Costa Abstract: The Amazon plays a crucial role in the global carbon cycle, storing a significant amount of carbon in the soil, particularly in the surface layers. However, practices such as deforestation, pasture expansion, and monoculture cultivation have altered these stocks, contributing to climate change. This study was conducted in the eastern Amazon, in the municipality of Bujaru, Pará state, with the objective of evaluating the effects of different land uses (fallow pasture, eucalyptus plantation, and secondary forest) on soil organic carbon stocks. Soil samples were collected from four depths (0–10 cm, 10–20 cm, 20–40 cm, and 40–60 cm) in ten 20 m × 50m plots within each study area. The results showed that carbon stocks were significantly higher in the surface layers (0–10 cm), with fallow pasture storing 0.2997 Mg ha−1 (29.97% of the total), while secondary forest and eucalyptus accounted for 24.81% and 22.17%, respectively. Statistical analysis indicated that carbon stocks varied according to depth, with positive correlations between organic carbon and organic matter (r = 0.67, p < 0.001). Secondary forest showed a more balanced carbon distribution, whereas pasture and eucalyptus concentrated carbon in the upper layers. This study contributes to the understanding of the relationship between land use and carbon sequestration, providing insights for sustainable management practices and climate change mitigation strategies in the Amazon.