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- Campus Samambaia, Campus Colemar Natal e Silva, Campus Aparecida de Goiânia.
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Avaliação da influência das variáveis climáticas no desempenho de estruturas de pavimento flexível através de critérios empírico-mecanísticos
(Universidade Federal de Goiás, 2025-06-25) Cordeiro, Marcus Vinicius Soares; Garcia, Liosber Medina; Garcia, Liosber Medina; Silva, João Paulo Souza; Mendes Filho, Walter Manoel
The Brazilian road network, predominantly composed of asphalt pavements, exhibits performance that is highly sensitive to environmental factors such as temperature, humidity, and precipitation. Empirical-mechanistic methods, such as MeDiNa and MEPDG, have been adopted to provide greater accuracy in predicting structural behavior over time. However, these methods—especially the MEPDG—lack proper calibration and adaptation to Brazil’s regional climatic data, as they were originally developed based on conditions in the United States. This research conducts a literature review of the main pavement design methods used in Brazil and abroad, comparing their approaches regarding traffic, materials, and climate. Project parameters and control variables were defined based on local conditions in the city of Goiânia (GO). For the simulations, the AASHTOWare Pavement ME Design software was employed, with its original North American climate database adapted using local meteorological information. The studied pavement structure includes asphalt surface, base, subbase, and subgrade layers, with mechanical properties determined from the literature. The simulation results provided relevant insights into rutting, alligator cracking, and the International Roughness Index (IRI). It was observed that rutting was highly sensitive to variations in temperature and wind speed, with an evaluation indicating that a 5% increase in temperature combined with a 5% reduction in wind speed could compromise up to 11.74% of the structure, especially in the surface layer, which showed variations of up to 20.54% across the simulated scenarios. Regarding alligator cracking, a significant and exponential increase over the years was noted. A noteworthy trend was identified, in which simulations with lower levels of permanent deformation generally exhibited higher cracking incidence. The same trend was observed for the IRI, which showed lower values in scenarios with higher rutting. In summary, these results highlight the importance of considering climatic criteria when applying mechanistic-empirical methods in the design of flexible pavements, especially in regions with diverse climates, such as the tropical conditions present in Goiânia.
Indolbutyric Acid (IBA) in the African Mahogany (Khaya grandifoliola C. DC.) cuttings and mini-cuttings development
(2020) Silva, Marília Gabriela da; Zaidan, Úrsula Ramos; Borges, Canrobert Tormin; Silva, João Augusto da; Resende, Rafael Tassinari; Venturoli, Fábio; Pires, Patrícia Pereira
The current expansion of the forest sector in the Cerrado (Brazilian Savannah), especially of the species of genus Khaya sp. (African Mahogany), requires several silvicultural and technical studies of various natures. Seed and clonal propagation enable noble and vigorous seedlings, which will future compose commercial plantations aiming timber production. The species Khaya grandifoliola C. DC is considered of distinct wood features and with great economic potential. The objective of this work was to evaluate the effect of different indolbultyric acid (IBA) concentrations – between 0 and 12 g.L-1 – on the rooting of K. grandifoliola cuttings (clonal origin) and mini-cuttings (seed origin). The experiment was carried out at the "Mudas Nobres" private nursery, located in Goiânia (Goiás State, Brazil). The experiment was conducted in a completely randomized design in a 5 × 2 factorial scheme. Multivariate, Neural Networks and Random Forest models were also applied to estimate the number of shoots in clonal cuttings, according to the data observed in seed mini-cuttings. The results indicate that IBA has the opposite effect on the two evaluated types of propagule origin, being more suitable for seed mini-cuttings (should apply 8 g.L-1 of IBA) and less suitable for clonal cuttings (should not apply IBA). In the operational nursery routine, if a standard application must be recommended (to cuttings either mini-cuttings), the most appropriate concentration is 6 g.L-1 of IBA.
Danos em Khaya ivorensis provocado por Trigona spinipes na savana brasileira
(2017) Moura, Rebecca Silva de; Souza, Kellen Rabello de; Souza, Daniel da Silva; Santana, Gabriel Mendes; Oliveira, Guilherme Murilo de; Venturoli, Fábio; Silva Neto, Carlos de Melo e
Trigona spinipes (Dog bee) attack the apical bud of Khaya ivorensis causing atrophy and budding which provoke branches that will depreciate the shaft if not handled. Damage to the culture of K. ivorensis has been reported for Brazil, but never before for the Brazilian savannah. The aim of this study was to survey the dog bee attack and report as first record the presence and damage caused in the African mahogany plantations in the Brazilian savannah. The area has about of 16.6 hectares of African mahogany monoculture in the municipality of Piracanjuba, Goiás. It has been used 21 plots of 400 m², pre-defined and simple random sampling method, in which was carried out forest inventory and observation sprouts the apical part of the stem and consequent artificial pruning of sprouts. Also performing were viewed bees in foraging of activity by cutting the shoots of K. ivorensis. In planting, 6.14% of the trees had regrowth and this percentage may indicate the number of attacked trees. The total trees with regrowth is a large quantity of trees which may develop with problems, generating more than one stem or branch, thereby preclude the affected wood is used for furniture.
Nutritional supplementation required by native Cerrado species development, in nursery
(2018) Matias, Renan Augusto Miranda; Venturoli, Fábio; Martins, Rosana de Carvalho Cristo; Pieruzzi, Fernanda Piccolo; Abreu, Alexandre Leandro Santos de; Matias, Mirella Basileu de Oliveira Lima
The ecological restoration of Cerrado ecosystems involves challenges pertinent to the fertilization of the substrate for seedlings in nursery, which are often produced by a single type of substrate. However, habitat heterogeneity suggests that the species may have different nutritional requirements. The objective was to assess the effect of substrate fertilization and nutritional supplementation by leaf in developing seedlings of Kielmeyera coriacea Mart. & Zucc. Eugenia dysenterica (Mart.) and DC Handroanthus impetiginosus (Mart. ex DC.) Mattos. The experiment was implemented in a 3x3 factorial completely randomized design (three types of substrates x three levels of foliar fertilization), with ten replicates. The treatments were tested by analysis of variance. For K. coriacea and H. impetiginosus, it is recommended to use a substrate composed of Soil + Manure (2:1), for E. dysenterica, it is recommended to use the complete substrate. Foliar fertilization is not recommended for all species. Regarding the soil analysis, organic matter, phosphorus and calcium were determinants in the formation of fertility groups for each of the major components of the Principal Component Analysis.
Floresta Estacional: madeira para o produtor rural no Cerrado
(2016-03) Souza, Kellen Rabello de; Oliveira, Guilherme Murilo de; Ferreira, Fernanda Gomes; Martins, Thalles Oliveira; Silva Neto, Carlos de Melo e; Venturoli, Fabio
This study had as objective to characterize the flora from a forest fragment and to analyze the diametric structure of commercial species in a semidecidous forest fragment, in Pirenópolis – Goiás. The studied fragment has 8820 m² and was randomly sampled through 21 Prodan points, where diameters at breast height (DBH) were measured and total heights were estimated in each point. The forest showed a diametric distribution adjusted to negative exponential curve. The estimate for total individuals was 810, 19 trees ha-1 and the volume estimative was 147,95 m³ ha-1. The highest Importance Values (IV) were represented by Apuleia leiocarpa, Davilla elliptica, Virola sebifera, Protium heptaphyllum, Dipteryx alata, Inga cylindrica e Emmotum nitens, and the floristic richness was 46 species, the Shannon index was 3.25 and the equability was 0.91. The potential species and the ones that are already marketed were: Anadenanthera colubrina, Apuleia leiocarpa, Copaifera langsdorffii, Physocalymma scaberrimum, Platypodium elegans, Virola sebifera, e Chrysophyllum gonocarpum, representing 24,6% of arboreal density in the site. This study demonstrated that forest fragment is capable to be managed, however complementary studies are necessary.