Marcos Felipe Nicoletti

The exploitation of native forests significantly reduced the original forest cover of southern Brazil in the first decades of the 20th century. There was an increase in the demand for these resourc...

O desbaste permite diferentes formas de condução, sendo o desbaste alto relevante por aumentar o diâmetro das árvores e gerar madeira de melhor qualidade. Este estudo teve como objetivo caracterizar um povoamento de Eucalyptus dunnii Miaden submetido ao desbaste seletivo alto, com intensidades distintas. Os regimes de manejo foram quatro: sem desbaste (T) e remanescentes de área basal de 12 (G12), 14 (G14) e 16 m² ha?¹ (G16). Todos os tratamentos com desbaste visaram uma população final de 250 árvores ha?¹, com diferentes intensidades ao longo do tempo. Foram analisados diâmetro à altura do peito (D), altura total (H), área basal e volume individual e total por estatística descritiva, histogramas de densidade e teste de Scott-Knott. O desbaste seletivo alto aumentou significativamente o D e o volume individual (v). A altura não foi afetada a partir dos 12 anos. Até os 11 anos, G14 e G16 apresentaram os maiores volumes por hectare, enquanto aos 19 anos o maior estoque foi observado no T, devido ao maior número de indivíduos de menores diâmetros. Conclui-se que o desbaste seletivo alto em E. dunnii favorece o incremento diamétrico e o volume individual, podendo ser utilizado para ganhos em qualidade da madeira e multiprodutos.

Este estudo objetivou avaliar qual Função de Densidade Probabilística (FDP) melhor representa a estrutura diamétrica de Ocotea pulchella (Nees & Mart.) Mez, Lithraea brasiliensis Marchand, Nectandra megapotamica (Spreng.) Mez e Matayba elaeagnoides Radlk., em fragmentos de Floresta Ombrófila Mista (FOM) com histórico de corte seletivo, em Campo Belo do Sul, Santa Catarina, Brasil. Modelos probabilísticos amplamente utilizados como Beta, Exponencial, Normal, Log-Normal, Weibull 2p e 3p foram ajustados e comparados por critérios estatísticos de aderência, sendo eles: Kolmogorov-Smirnov, Critérios de Informação de Akaike (AIC) e Bayesiano (BIC), log-verossimilhança, pseudo-R² e erro padrão da estimativa. Os resultados indicaram que Weibull 3p apresentou o melhor desempenho para todas as espécies, evidenciando maior acurácia na representação da frequência diamétrica. M. elaeagnoides exibiu padrão próximo ao formato de J-invertido, indicando regeneração contínua, enquanto N. megapotamica apresentou baixa densidade nas classes jovens, sugerindo limitação no recrutamento. Já O. pulchella e L. brasiliensis mostraram maior irregularidade estrutural, possivelmente associada ao corte seletivo e à reorganização populacional ao longo do tempo. Concluiu-se que as FDPs, especialmente a Weibull 3p, são ferramentas eficientes para descrever a estrutura diamétrica dessas espécies, contribuindo para ações de manejo, conservação e restauração de áreas da FOM sob histórico de corte seletivo.

The Pyrenean oak (Quercus pyrenaica Willd.) forests are of high ecological and socio-economic importance, across the southwestern European region, particularly in the Iberian Peninsula. Historically, oak acorns served as a key resource for forest regeneration, wildlife, and human consumption. We hypothesize that acorn availability is significantly driven by environmental and forest factors, and that these drivers create spatially distinct areas of higher production potential. A total of 59 forest inventory plots (500 m² each) were established in 2022 within the Montesinho Natural Park, and acorns were collected and classified in each plot over three consecutive years (2022–2024). Dendrometric, topographic, and climatic parameters were recorded, and outstanding production plots were defined as those with acorn availability exceeding 100 kg ha⁻¹ in all three years.,Results revealed high interannual variability in acorn availability, with a mean of 104.0 kg ha⁻¹ for fully mature acorns and 134.8 kg ha⁻¹ for not fully mature acorns. Availability was positively correlated with minimum, mean, and maximum temperature, tree quadratic diameter, and the topographic wetness index, and negatively correlated with minimum, mean, and maximum precipitation and stand density. Approximately 24% of plots were classified as high productivity (>100 kg ha⁻¹ year⁻¹), associated with stands having larger quadratic diameters, lower tree density, and located in lower altitudes.,Pyrenean oak fruiting exhibits natural seasonality influenced by climate and forest structure, yet clear criteria for identifying areas with higher acorn availability were identified.

Every forest carries in its structure traces of exploitation and resilience, but how interpret this narrative? This study investigated whether different disturbance histories lead to distinct functional strategies in fragments of Mixed Ombrophilous Forest. We analyzed specific leaf area, leaf dry matter content, wood density, diameter at breast height, biomass, and carbon using community-weighted means, multivariate and statistical analyses. Conserved fragments showed significantly higher diameter, biomass, and carbon stocks (t-test, p < 0.05), indicating conservative strategies, whereas selectively logged fragments exhibited higher wood density and leaf dry matter content (t-test, p < 0.05), revealing unexpected patterns. Pearson correlations were stronger and more homogeneous in conserved fragments, while selectively logged forests displayed more variable association patterns among functional attributes. These findings suggest that selectively logged forests may follow distinct functional trajectories shaped by logging legacies and regeneration processes, highlighting the value of functional traits for understanding forest recovery and ecosystem dynamics.

Given the ecological significance and potential for afforestation and carbon sequestration of these species, this study contributes to optimizing nursery practices for successful regeneration and conservation efforts. Thus, this research assessed the physical and physiological seed quality and seedling production of Sequoia sempervirens, Sequoiadendron giganteum, and Pseudotsuga menziesii. For seed characteristics the following were tested: (I) Tetrazolium at concentrations: 0.0%, 0.1%, 0.5%, 1.0%; (II) moisture content and thousand-seed weight; (III) in-lab germination; and (IV) the classification of seeds’ viability through the use of a seed blower. Meanwhile, seedling production was tested: (I) five compositions of substrates and (II) doses of a controlled-release fertilizer (14-14-14): 0.0, 2.0, 4.0, 6.0, 8.0 g L⁻¹, for S. giganteum. The seed evaluations revealed no significant effect of tetrazolium concentrations on determining their viability. The water content results classify all species as orthodox. All species’ seeds were classified as small according to the weight of a thousand seeds. A maximum of 41% germination was observed for both S. sempervirens and S. giganteum, this value was 56% for P. menziesii, attributed to non-viability and emptiness. The seed blower increased germination by more than 20% for S. giganteum and almost 40% for P. menziesii. Seedling production was affected by the substrates, and a dosage of 4.0 g L⁻¹ of the controlled-release fertilizer is recommended for S. giganteum.

O manejo florestal em fitofisionomias com Araucaria angustifolia (Bertol.) Kuntze, é um tema relevantes ao longo dos últimos anos, mas ainda faltam abordagens estruturais para entender a dinâmica da espécie em diferentes cenários. Esse estudo dendrocronológico de 60 anos, tem como objetivo o uso de modelos lineares de regressão múltipla para definir variáveis que melhor expliquem o incremento periódico em área basal individual (IgP) de A. angustifolia, em fragmentos de crescimento antigo e secundários. Para as análises foram utilizadas 45 árvores no crescimento antigo e 29 no secundário, que consistiram na determinação da largura dos anéis de crescimento ao longo do tempo, para posterior ajuste de modelos pela função stepwise por meio do método backward, visando a avaliação de suas variáveis quali-quantitativas. Os ajustes dos modelos de crescimento da floresta de crescimento antigo se mantêm estáveis e com precisão superior a 80% ao longo das décadas estudadas, enquanto, nas florestas secundárias, a qualidade dos ajustes tende a diminuir à medida que o tempo passa. Ambos os cenários apresentaram um crescimento de aproximadamente 0,063 m² de área basal individual ao longo dos 60 anos, porém com taxas individuais de incremento periódico diamétrico superior nas florestas secundárias (2,1-16,4 cm), em comparação as florestas de crescimento antigo (1,9-11,5 cm). Concluiu-se que pelo método stepwise, cinco variáveis foram ideais para modelar o crescimento de A. angustifolia, com taxas de crescimento basal semelhantes, mas distintas do crescimento diamétrico, sendo que as florestas de crescimento antigo apresentaram maior estabilidade que as secundárias.

Background: This study aimed to recover the silvicultural history of a 58-year-old Pinus elliottii stand, monitor its growth rate and volume evolution of assortments, especially in the older tree ages. Methods: The study area is located in the Três Barras National Forest, SC, Brazil, and composed of four stands established in 1963, totaling an area of 8.95 ha. The studied stand was subjected to 4 mixed thinnings at 6, 14, 23 and 36 years of age, with the latter in 1999, and since then they have not undergone any further intervention. A census of the stands was conducted in 2013 and 2021; increment cores of 33 trees were collected in the four stands in 2021. A retrospective analysis and estimation of DBHs were performed in the years in which thinning was performed, hypsometric estimates were made, volume and assortment were calculated at the ages of the interventions using equations available in the literature. Results: A reduction in diameter growth and stabilized height growth of trees was observed after 36 years, the date of the last thinning. Even so, it was found that 78% of the volumes at 50 years were of the most valuable assortment and 83% at 58 years. Conclusion: There is a need for an economic, sensitivity and risk assessment to assess and identify the viability of long-term planting, especially the optimal age to balance wood production and proportion from the most valuable assortments in the shortest time.

O objetivo deste estudo foi avaliar as características morfométricas e modelar os principais índices morfométricos de um povoamento de P. taeda, submetido a diferentes regimes de desbastes. Foram coletadas informações de circunferência a altura do peito (cap), altura total (h) e altura de inserção de copa (hic) e raios de copa (N-S, L-O) de 252 árvores pertencentes a nove tratamentos (T0: sem desbaste, T1: desbaste fraco, T2: fraco/médio, T3: médio, T4: médio/médio, T5: médio/forte T6: sistemático, T7: forte, T8: extremo). Posteriormente, foram calculados os índices morfométricos de diâmetro de copa (dc), comprimento de copa (cc), proporção de copa (pc), grau de esbeltez (ge), índice de saliência (is), índice de abrangência (ia) e formal de copa (fc). Para a modelagem dos índices morfométricos foram ajustados oito modelos matemáticos para estimar a variável dc, e para os demais índices foi realizado a modelagem pelo método Stepwise. Os critérios de seleção da melhor equação foram o R²aj, Sy.x%, significância dos coeficientes e análise gráfica dos resíduos. Foi realizado a correlação entre os índices morfométricos por Pearson a 95% de probabilidade. De maneira geral, as aplicações dos desbastes favoreceram o crescimento da copa das árvores com crescimento gradativo à medida que se intensificava o desbaste, sendo que o extremo apresentou ac média quatro vezes maior que os demais, influenciando diretamente no dap médio e nos índices de diâmetro de copa e grau de esbeltez. As equações deste estudo podem ser utilizadas para estimar as variáveis de grau de esbeltez.

The study addressed the use of models to estimate dendrometric variables in a commercial plantation of Pinus taeda L. Allometric relationships were applied to estimate diameter at breast height (DBH) based on stump diameter (SD), providing a mathematical approach to relate these two variables. Additionally, a "conventional" measurement exclusively of DBH was conducted to compare the values obtained with traditional approach to the results of the proposed modeling. The study also explored hypsometric relationships to estimate tree height as a function of DBH, enabling an efficient and economical assessment of tree characteristics in the forest stand. Furthermore, a forest census was conducted in the area, allowing a comprehensive comparison between the methods used and the actual data from the forest stand, reinforcing the importance of these approaches for effective forest resource management. The results showed that the models were effective in estimating volume, basal area, and the number of trees per hectare, with consistent results compared to the forest census. Therefore, the study concludes that stump inventory methods are effective in estimating dendrometric data in Pinus taeda L. plantations, even after forest cutting events, thereby supporting forestry experts in conducting precise assessments in areas with completed timber harvesting and in making informed decisions. This contributes to the effective and sustainable management of forest resources and the enforcement of laws in cases of environmental or economic damage.