This study aimed to develop a system for production prognoses for Pinus taeda L. plantation using Stand Density Management Diagram (SDMD) associated with diameter class models. The database used came from permanent plots measured in the Paraná and Santa Catarina states, southern Brazil. The methodology proposed by McCarter and Long Western Journal of Applied Forestry 1:6-11 (1986) and Dean and Baldwin (1993) was used in constructing the SDMD, which can generate stand attributes used as input in a diameter-class model, thus providing detailed prognosis of wood assortments in thinnings and final cut. With attributes from SDMD the parameters Weibull function are recovered by the method of moments and with the association of these two models types a production system was developed. The developed system can indicate the correct timing for thinnings and final cut (SDMD) and the most appropriate and profitable management regimes using the projection of the wood assortments (diameter-class model) and respective market values in a simply, quickly and economical way. The new methodology is an important tool, especially for forestry enterprises on small properties with the use of an easy-to-apply system by a forestry technician, which can reduce the forest rotation, implement the cuts at the right time, and in turn avoid mortality. Stand Density Management diagrams (SDMD) are excellent tools for defining the appropriate moment to perform thinnings and final cut, avoiding self-thinnings, but they are not capable of detailing the wood assortment. We built a system that uses SDMD to generate input variables for a diameter-class model. This association can indicate the correct time to perform thinnings and final cut (SDMD) and the most appropriate management regimes using the projection of the wood assortments in a simply, quickly and economical way.

This study modeled the diameter growth of Araucaria angustifolia, Cedrela fissilis, and Ocotea porosa as a function of age and analyzed how these factors are related to diameter distribution. This analysis was used to describe behavior in terms of age and lifespan, and also determined periods of technical growth stagnation for each species. Diameter growth was evaluated via partial trunk analysis using increment cores from 30 trees per species in six study locations in southern Brazil (totaling 480 cores), collected in proportion to diameter distribution. Twelve biological models were utilized to estimate diameter growth as a function of age of the species in the different locations. The Weibull probabilistic density function with three parameters was adjusted to represent the diametric structure and indicate carrying capacity. Distinct ages were identified in the different study locations, indicating successions in separate periods during the past as well as locations with the least alterations (oldest successions). The diameters at the technical age of stagnation and carrying capacity were found to be generally similar, demonstrating the relationship between diameter structure and diameter increment. Maximum vigor in the three species was found to occur at diameters considerably smaller than the maximum value, suggesting that attainment of significant ages and diameters may not fully reflect the inherent potential of all individuals within the species under study. The maximum diameter increment vigor in the species under analysis was observed during the early stages of development, and tended to diminish in the subsequent phases.

O objetivo deste trabalho foi mapear a distribuição das variáveis dendrométricas e definir Unidades de Manejo em plantios comerciais de teca, por meio da krigagem com deriva externa, considerando os atributos químicos do solo. Para isso, o presente estudo foi conduzido em plantio comercial de teca situado no município de Nossa Senhora do Livramento, estado de Mato Grosso - Brasil, constituído por povoamento seminal implantado no ano de 1999, perfazendo o total de 223,16 hectares de efetivo plantio. Os dados foram coletados em 46 unidades amostrais, nas quais foram também coletadas as amostras de solo para caracterização química no 2º, 9º e 17º ano. Apesar da possibilidade de definir as Unidades de Manejo utilizando qualquer variável dendrométrica, o presente trabalho buscou estabelecer as Unidades de Manejo em função do produto florestal desejado, ou seja, do volume (V). As Unidades de Manejo para teca podem ser aplicadas no estudo da relação entre o volume (V) e os atributos químicos do solo (potássio trocável – K+, cálcio trocável – Ca2+ e Alumínio trocável Al3+) para os anos de 2008 e 2016. A possibilidade de estabelecer relações espaciais entre o desenvolvimento da teca e os atributos químicos do solo permite a prescrição de intervenções silviculturais precisas e direcionadas para as diferentes condições edáficas, visando a maximização da produção ao longo da rotação da cultura. Portanto, a definição das Unidades de Manejo é uma importante ferramenta de suporte à decisão quando o objetivo é definir a prática silvicultural a ser adotada para cada Unidade de Manejo.

ABSTRACT Accurate wood volume predictions are critical in hyperdiverse forests because each species has specific size and shape traits. Although generic models at a multispecies level were widely used in Amazonian managed forests, they are subject to more significant bias due to interspecific variability. We used an extensive database of wood volume collected in managed forests to test the hypothesis that generic models violate the independence assumption due to that predictions vary with species-specific size. Our hypothesis was proved as residuals of the generic model were conditioned to species and specific size. The multilevel models were more accurate both in fitting and validation procedures, and accounted for variance derived from species and specific size, providing a more reliable prediction. However, we found that the size-specific models have a similar predictive ability to species-specific models for new predictions. This implies more practical estimates in hyperdiverse forests where fitting species-specific models can be complex. The findings are crucial for sustainable forest management as they allow for more reliable wood volume estimates, leading to less financial uncertainty and preventing damage to forest stocks through under or over-exploitation.

O incremento diamétrico é uma variável de complexa estimativa em florestas naturais, especialmente dada a composição de espécies e o lento crescimento das árvores. Para essas situações, algumas pesquisas têm voltado sua atenção ao emprego de modelos de crescimento de árvores individuais, aliando com estratégias de agrupamento de indivíduos ou espécies, em que o objeto de estudo é o próprio indivíduo arbóreo. Este trabalho teve como objetivo estimar o incremento diamétrico de árvores em um remanescente natural de Floresta Ombrófila Mista, visando investigar metodologias de formação de grupos de indivíduos que favoreçam a estimativa do incremento diamétrico individual. Os grupos foram formados a partir de uma metodologia em dois estágios, a primeira via diâmetro padronizado e a segunda via uma razão. relacionando diâmetro relativo, incremento diamétrico e índices de competição. O incremento diamétrico foi estimado a partir de um estimador de razão utilizado de forma a conciliar a estratégia de agrupamento. O agrupamento classificou de forma satisfatória os indivíduos, em que os índices de competição foram relevantes para essa classificação. O uso do diâmetro padronizado (dp) foi oportuno para uma melhor separação dos indivíduos. O erro de estimativa do incremento diamétrico foi de 0,0599 cm.ano-1 para os dados de treino e 0,0765 cm.ano-1 para os dados de validação. A estimativa do diâmetro futuro teve um erro médio de 4,52%. A combinação da dupla estratificação com o estimador de razão foi satisfatória para estimativa precisa dos incrementos diamétricos de todas as espécies arbóreas.

O intuito desse estudo foi modelar o crescimento e a produção de plantios de Pinus taeda L. com modelos globais, de distribuição diamétrica e de árvores individuais. Os dados utilizados foram provenientes das medições de 345 parcelas permanentes localizadas no estado de Santa Catarina. Para avaliar a projeção da produção em volume pelos diferentes métodos estudados, 89 parcelas foram selecionadas para compor o conjunto de dados para validação. Aplicou-se o teste estatístico de Wilcoxon para avaliar igualdade estatística dos volumes estimados e observados. As estatísticas de viés e acurácia também foram utilizadas para avaliar as projeções dos volumes totais. Para obtenção dos parâmetros futuros da fdp de Weibull, foram utilizados os métodos dos percentis. Dentre todas as categorias testadas, o modelo global de Clutter (1963) é o mais preciso e acurado para a prognose da produção total com viés médio de -9,80 m3 ha-1 e acurácia média de 33,60 m3 ha-1. A modelagem de distribuição diamétrica também apresenta bons resultados. O sistema de árvores individuais não apresenta estimativas precisas e acuradas. O resultado do teste estatístico de Wilcoxon mostra que existe diferença estatística entre os valores observados e estimados entre todos os métodos.

RESUMO Esta pesquisa originou-se de uma base de dados de dois inventários a 100% realizados em 1984 e 2000, sobre uma mesma área de 576 ha de floresta tropical primária, localizada na Floresta Nacional do Tapajós (FLONA TAPAJÓS), Belterra, Pará. O objetivo foi avaliar os níveis de erros na obtenção de variáveis de locaçã (xi, yi) e diâmetro à altura do peito (DAP), com base nos inventários comerciais a 100% realizados em 1984 e 2000 na FLONA TAPAJÓS. Nos dois inventários, as circunferência à altura do peito (CAP) foram medidas com fita métrica, sendo que as alturas comerciais em 1984, foram medidas com o hipsômetro de Weise e, em 2000, estimadas com o uso de varas, o DAP mínimo em 1984 foi de 55cm para todas as espécies e, em 2000, foi adotado o DAP mínimo de 35cm. O erro médio global de medição do DAP (cm) para as 6 espécies analisadas variou de 2 a 5% e em termos de classe diamétrica variou de 8 a 17%. A pesquisa também mostrou que o nível global do erro médio de estimativa da distância até 5 metros foi de aproximadamente 14%, sendo que 41% do erro foi atribuído a distâncias que variaram de 5 a 10 metros e que cerca de 60% do erro se concentrou na distância acima de 10 1 metros. A avaliação do erro médio de estimativa das coordenadas (xi, yi ) mostrou que o método utilizado em 1984 e o método atualmente adotado pela TREVISO na FLONA TAPAJÓS produziram resultados considerados satisfatórios para o planejamento do manejo florestal.

The knowledge of forest populations dynamics after logging and under the events of silvicultural treatments is important to establish management and conservation strategies. We aimed to show results of structural changes of tree species populations (from seedlings to adult trees), during 27 years in an area where reduced impact logging and silvicultural treatments were performed. In 1985 timber of trees with DBH ≥ 60 cm was logged from 400 ha, considering three volume reduction intensities (15, 25, 35%). In 1994, thinning was applied considering individuals with DBH ≥ 15 cm, and four intensities of basal area reduction (0, 30, 50, 70%). Twelve statistical treatments were performed considering the thinning combined with harvest intensities. Trees, saplings, sticks and seedlings were monitored and measured in 40 permanent sample plots. The plots were assessed in 1984, 1986, 1994, 1996, 2004 and 2011. Statistical analyses were performed using generalized linear models. Our results show that forest structure was not altered significantly even in areas where the trees basal area reduction was higher. There was no significant influence on the establishment of the main species in the area and in dynamics of the remnant forest after logging.

Áreas destinadas à conservação desempenham papel essencial na regulação global do clima, pois, as florestas são o principal sumidouro de carbono terrestre, uma vez que, capturam dióxido de carbono da atmosfera e armazenam o carbono em sua biomassa, principalmente na madeira. O objetivo deste trabalho foi analisar a dinâmica nos estoques de volume, biomassa e carbono em área total da Bacia Hidrográfica do Rio Iguaçu e em áreas especiais, como Matas Ciliares, Unidades de Conservação, Terras Indígenas e Assentamentos Rurais, entre os anos 2000 e 2015. Foram utilizados arquivos vetoriais da cobertura florestal da bacia para os anos-base para a estimativa das variáveis por formação florestal e estágio sucessional. A Bacia Hidrográfica do Rio Iguaçu como um todo foi sumidouro de carbono nos 15 anos analisados, com aumento nos estoques na ordem de 14% para V, AGB, C e CO2eq (sequestro de 116.173.629,91 t de CO2eq) no período. As áreas especiais foram sumidouro de carbono, sendo que as Unidades de Conservação estocaram mais carbono (11,72% do total da bacia) e Matas Ciliares sequestraram mais carbono (3,54% do total da bacia). Palavras-chave: Mata Atlântica; mudanças climáticas; floresta subtropical.

Araucaria angustifolia is the dominant coniferous species in Brazil, a long-lived pioneer species and a supplier of valuable timber and non-timber products, which gives it key-species status. This study examines how A. angustifolia population structure affects the stand structure, and whether these relationships differ between protected and unprotected areas. The study was carried out on two protection status forests (national forest and urban forest) in a region of Atlantic mixed forest in Paraná State, southern Brazil. Skewness coefficient and the Weibull shape parameter described the population structure and its effects on species diversity and biomass stock. Population diameter distribution differed significantly between forests, with unbalanced structure in both, although regeneration was more abundant in the protected area. Skewness positively affected aboveground biomass whereas shape negatively affected it and species diversity. These relationships differed between protected and unprotected stands. The effect of A. angustifolia populations on stand structure was conditioned on protection status. Old-growth populations may have lower diversity and biomass stock even supporting large trees. Consequently, old-growth forests, can lead to wood loss through mortality, senescence, and declining populations, representing the waste of a valuable timber resource. These findings provide useful knowledge for forest management, species conservation, and the carbon market.

Assessing variations in tree allometry is useful for understanding height growth strategies in relation to life-history trajectories, light competition and environmental restrictions. Scaling exponent and asymptotic heights obtained from height–diameter (HD) models may elucidate how trees optimise growth strategies and the potential drivers that influence tree height. Our main objective was to explore how the HD relationship in Bracatinga (Mimosa scabrella) varies along stands chronosequence and life history. The study was carried out in discontinuous stands located across the metropolitan region of Curitiba, southern Brazil. We used HD data from 300 temporary plots in chronosequences dating from a disturbance, which represented stand development after intervention, covering the life history of the species. Power and exponential models were fitted to data to describe the HD relationship over time. Mixed-effects models were applied to explain the height variations by stand characteristics. We found that tree height and allometry were influenced by stand development phase and tree life stage along the chronosequence. Changes in tree height were also driven by light competition related to certain stand characteristics, such as basal area, stem density and species diversity. We concluded that growth strategies are conditioned by interactions between light requirements along a tree’s life history and successional stand evolution. The results revealed that gradual changes in tree development might be recognised by stationary data along chronosequences. Quantifying changes in HD allometry has ecological and practical applications for explaining the strategies and drivers underpinning tree growth and providing useful knowledge for improving growing stock predictions and stand management.

The demographic processes of a tree community, such as recruitment and mortality of individuals, significantly affect the other dynamic and structural events of forests. The objective of this research was to evaluate the recruitment and mortality rates of Araucaria angustifolia (Bertol.) Kuntze in forest remnants in Southern Paran ' a. Data came from seven permanent sample plots of 1 ha each, installed in 1999 and monitored annually for 14 years. Mortality and recruitment, as well as gain and loss rates of basal area, were obtained for the plots, which represent distinct structural features of the remnants. The data indicated that there is not equilibrium among the rates of mortality and recruitment. In general the rate of recruitment was significantly higher than the rate of mortality. From the seven studied plots only two of them had higher rates of mortality than recruitment. The density of the plots had a direct influence on mortality and an inverse influence on recruitment.

Many forest companies in Brazil started using plots of varying sizes in their continuous forest inventories (CFI), mainly to avoid the effects of marginal trees and to obtain more consistent estimates in the CFI.Consequently it was quite important to present a comparison between the results of applying a sampling method in which trees are selected with probability proportional to a variable average area with the method in which the trees are selected with probability proportional to a fixed area plot.In this study, the theory for a sampling method was developed, in which a selection of a group of trees in a plot is done with probability proportional to a variable average area of occupation (PPVA) per 60 trees in a plot.The data is composed by 41 permanent plots from a forest inventory of Eucalyptus dunnii Maiden in Santa Catarina, Brazil.In order to compare the PPVA method with the traditional fixed area method (PPA), the area was imaged with an unmanned aerial vehicle (UAV), allowing to obtain a full list of living trees (census).For this fraction, 7 plots for PPVA method and 7 for the PPA method were also measured, allowing the comparison of the total volume obtained in the census with PPVA and PPA results.The total volume of the plot obtained as a function of the census, when compared to the PPVA method, did not present significant differences at the 99% probability level, while the fixed area method was statistically different at the 95% probability level, resulting in an overestimation of 7.5% higher than that found in the census.The PPAV sampling method provides parameter estimates for characterization of the forest population at a lower cost; it becomes more effective than sampling with fixed area plots, because they are practical and operationally easy for delimitation in the field, providing appropriate estimates and more accurate average occupational area for each individual tree (m 2 ) in the population.

Campomanesia xanthocarpa is a fruit tree species of the Myrtaceae family with potential for fruit commercialization; however, studies on the genetic diversity and variability of the species are necessary to make it commercially viable. The objective of this study was to characterize the diversity and intrapopulation spatial genetic structure (SGS) of a C. xanthocarpa population and compare the genetic parameters of quantitative traits between and within open-pollinated progenies. For the analysis of genetic diversity, 80 individuals from a population in the Irati National Forest, Parana, Brazil, were analyzed. The observed (Ho) and expected (He) heterozygosity, fixation index (F), and intrapopulation spatial genetic structure (SGS) were assessed. To analyze the quantitative traits, a field progeny test was installed using a randomized block design with nine progenies, three blocks, and four plants per plot at a spacing of 9 m². Total height (H), basal diameter (dbase), crown length and diameter (Ccrown and dcrown) at two years and nine months of age were measured. For the studied population, Ho and He had an average of 0.478 and 0.717, respectively, with an average fixation index of 0.333, suggesting that the population may be suffering from inbreeding. We found linkage disequilibrium for one evaluated pair of loci. SGS suggested a minimum distance of 25 to 50 m between mother trees for seed collection. For the quantitative genetic analyses, we found that average heritability ranged of 0.15 to 0.55 being considered from moderate (dbase) to high (H, Ccrown and dcrown). The traits H and dcrown were particularly noteworthy and can be used to obtain superior genotypes for the other traits (dbase and Ccrown), since the correlation was significant and high (> 0.80). The results provide applicable information for the implementation of breeding and conservation programs for the species.

Este trabalho teve como objetivo determinar e analisar o peso de carbono orgânico fixado na biomassa aérea de árvores de Pinus taeda L. em diferentes espaçamentos de plantio, aos nove anos de idade, na região de Irati-PR. Em cada tratamento foram selecionadas e marcadas em campo nove árvores, ou seja, uma árvore em cada classe diamétrica, visando determinações de biomassa aérea e carbono, totalizando 81 árvores distribuídas na área do ensaio. Cada árvore foi segmentada em: fuste, galhos verdes, galhos secos, acículas e casca. O efeito do espaço vital nos pesos de carbono fixados na biomassa, bem como os valores de carbono total por árvore foram submetidos a análises de estatística descritiva e experimental (homogeneidade de variâncias, análise de variância e teste de comparação de médias de Tukey), no delineamento inteiramente casualizado. O acúmulo de biomassa e peso de carbono fixado ocorreu prioritariamente no fuste, seguido pelos galhos verdes, casca, acículas e galhos secos. O peso de carbono fixado na biomassa de Pinus taeda foi afetado pelo espaço vital de crescimento.

A natural dependence among diameters measured within-tree is expected in taper data due to the hierarchical structure. The aim of this paper was to introduce the covariance generalized linear model (CGLM) framework in the context of forest biometrics for Pinus taeda stem form modeling. The CGLMs are based on marginal specification, which requires a definition of the mean and covariance components. The tree stem mean profiles were modeled by a nonlinear segmented model. The covariance matrix was built considering four strategies of linear combinations of known matrices, which expressed the variance or correlations among observations. The first strategy modeled only the variance of the diameters over the stem as a function of covariates, the second modeled correlation among observations, the third was defined based on a random walk model, the fourth was based on a structure similar to a mixed-effect model with a marginal specification, and the fourth was a traditional mixed-effect model. Mean squared error and bias showed that the approaches were similar for describing the mean profile for fitting and validation dataset. However, uncertainties expressed by confidence intervals of the relative diameters were significant and related to the matrix covariance structures of the CGLMs.

Forests play an important role in climate change, acting as a source or sink of carbon. There is, however, a lack of data regarding the carbon production from litterfall in tropical forests. The Atlantic Forest is one of the most distinguished forest types in Brazil, encompassing the Araucaria Forest. In this study, we assessed the seasonal carbon production from litterfall. Data were collected every season from 27 litter traps. Dry matter and carbon fraction were investigated and confronted with meteorological variables. Litterfall components were stratified into Brazilian pine leaves and twigs: broadleaved leaves, twigs, bark, reproductive material, and other material (miscellaneous). The Tukey test indicated significant differences among the carbon fractions for litter components. Seven key species were determinant in litterfall production. Brazilian pine leaves and twigs were the primary carbon source to the forest, followed by leaves and twigs from broadleaved species. Most carbon input from litterfall comes during spring and summer. We concluded that litterfall is a source of carbon and nutrient to the ecosystem. This study contributes to improving the Brazilian national greenhouse inventory and related reports addressed to climate change mitigation.

Modelos de árvores individuais permitem o maior nível de detalhamento possível da estrutura florestal e estudos recentes mostram que ainda existem lacunas de conhecimento principalmente quando se planeja obter a segmentação em multiprodutos. O objetivo deste trabalho foi ajustar um modelo completo de árvores individuais para estimar os volumes por sortimentos em plantios de Pinus taeda localizados no planalto norte do estado de Santa Catarina. O ajuste do sistema foi baseado nas remedições de 345 parcelas permanentes. Para estimativa dos sortimentos utilizou-se o modelo de Schoepfer (1966) e a cubagem rigorosa de 360 árvores. A mortalidade por hectare foi estimada a partir do ajuste do modelo de Buchman. O índice de competição independente da distância utilizado foi o de Stage (1973). O modelo proposto por Qin & Cao (2006) foi ajustado para projeção do diâmetro à altura do peito e altura total. Para a avaliação dos modelos, foram utilizadas o coeficiente de determinação ajustado (R²adj), erro padrão da estimativa e análise gráfica de resíduos. Utilizou-se o teste de Mann-Whitney para avaliar se os volumes estimados apresentam igualdade estatística quando comparados com os volumes observados. Os resultados do ajuste probabilidade de mortalidade foram um R2adj = 0,623 e SYX% = 41,9. Os modelos de estimativas de diâmetro e altura total apresentaram respectivamente um R2adj = 0,987, R2adj = 0,963 e SYX% =2,22, SYX% =4,04. O volume foi superestimado para todos os sortimentos em média 43,6 m3.ha-1 (29,8%). Quanto a acurácia os volumes diferiram em média em 45,6 m3.ha-1 (31,3%) dos volumes reais. O resultado do teste de Mann- Whitney mostrou que existiu diferença estatística entre os valores observados e estimados. O sistema de árvores individuais construído não apresenta projeções precisas e acuradas. Também gera-se estimativas que diferem estatísticamente dos volumes observados para todos os sortimentos.

This research investigated and characterized growth of Araucaria angustifolia (Bert.) O. Ktze, Cedrela fissilis Velloso and Ocotea porosa (Nees & C. Mart.) Barmso in Araucaria Forest in sites located within three States of southern Brazil, each one presenting different conservation stages. We evaluate diametric growth based on partial stem analysis using core samples from 30 trees by species at each study site (totalizing 480 trees), collected proportionally to the diametric distribution. The samples were collected for each species in six locations: Irati and Sao Joao do Triunfo, in Parana State, Tres Barras, Chapeco and Cacador, in Santa Catarina State and Sao Francisco de Paula in Rio Grande do Sul State. The oldest trees were observed in Cacador (A. angustifolia, 588 years old and O. porosa, 322 years old) and Irati (C. fissilis, 231 years old). The youngest ones were A. angustifolia in Chapeco (33 years), O. porosa in Tres Barras (26 years) and C. fissilis in Sao Joao do Triunfo (20 years). The largest average diameters for A. angustifolia and C. fissilis were found in Cacador (75 and 44.1 cm, respectively) and for O. porosa (54.5 cm) in Sao Joao do Triunfo. The age and the diametric classes of the trees affect growth, independent of the forest stock condition. Although differences in diameter growth of the three species have been attributed to variations in environmental conditions, it is suspected a greater influence of forest structure since similar climatic groups have showed distinct growth rates. Successional stages of the forest should also be considered when evaluating growth rhythm of the same species in different sites.