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Accurate estimation of biomass in natural vegetation sites remains a challenge. Modeling biomass growth and production in Cerrado areas is crucial to understanding the vegetation succession process, especially regarding the changes in biomass accumulation over time. Thus, our objective was to model the growth and production of woody aboveground biomass (living and total) in a cerrado stricto sensu monitored for 27 years after implementing management systems. As expected, the basal area (with a diameter taken at 30 cm from the ground level) is the most important predictor variable and showed a higher correlation with the biomass stocks and allowed accurate and consistent estimates of these accumulated stocks over time. Future estimates of biomass production, generated from growth models that estimate production as a function of parameters observed at previous ages, indicate that maximum stocks of living (25.86 ± 0.15 Mg ha−1 [mean ± standard deviation]) and total aboveground biomass (26.11 ± 0.15 Mg ha−1) are expected for a period between 28 and 30 years after the implementation of the management systems, with maximum mean annual increment between 23 and 27 years. Furthermore, the systems of equations obtained simulated reductions up to 30% of biomass after the occurrence of a forest fire at 23 years. Thus, our study can be useful for the decision-making process and developing public policies and strategies for managing and conserving natural resources in the Cerrado biome.

In forest modeling to estimate the volume of wood, artificial intelligence has been shown to be quite efficient, especially using artificial neural networks (ANNs). Here we tested whether diameter at breast height (DBH) and the total plant height (Ht) of eucalyptus can be predicted at the stand level using spectral bands measured by an unmanned aerial vehicle (UAV) multispectral sensor and vegetation indices. To do so, using the data obtained by the UAV as input variables, we tested different configurations (number of hidden layers and number of neurons in each layer) of ANNs for predicting DBH and Ht at stand level for different Eucalyptus species. The experimental design was randomized blocks with four replicates, with 20 trees in each experimental plot. The treatments comprised five Eucalyptus species (E. camaldulensis, E. uroplylla, E. saligna, E. grandis, and E. urograndis) and Corymbria citriodora. DBH and Ht for each plot at the stand level were measured seven times in separate overflights by the UAV, so that the multispectral sensor could obtain spectral bands to calculate vegetation indices (VIs). ANNs were then constructed using spectral bands and VIs as input layers, in addition to the categorical variable (species), to predict DBH and Ht at the stand level simultaneously. This report represents one of the first applications of high-throughput phenotyping for plant size traits in Eucalyptus species. In general, ANNs containing three hidden layers gave better statistical performance (higher estimated r, lower estimated root mean squared error–RMSE) due to their greater capacity for self-learning. Among these ANNs, the best contained eight neurons in the first layer, seven in the second, and five in the third (8 − 7 − 5). The results reported here reveal the potential of using the generated models to perform accurate forest inventories based on spectral bands and VIs obtained with a UAV multispectral sensor and ANNs, reducing labor and time.

Made available in DSpace on 2022-04-28T19:41:32Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-10-01 Growth and production models can help to simulate the growth of tree dimensions to predict forest productivity at different levels. In this context, the following questions arise: (i) is it possible to recognize the growth pattern of eucalyptus species based on spectral features using machine learning (ML) for data modeling? (ii) what spectral features provides better accuracy? and (iii) what ML algorithms are most accurate for performing this modeling? To answer these questions, the present study evaluated the use of ML techniques using breast height and total plant height to classify the growth of five species of eucalyptus and Corymbria citriodora in an unsupervised learning, and the obtained classes for induce ML algorithms to recognize the species with relation to their growth using vegetation indices (VIs) and spectral bands (SBs). It were evaluated five eucalyptus species (E. camaldulensis, E. uroplylla, E. saligna, E. grandis e E. urograndis) and C. citriodora in experimental design of randomized blocks with four replicates, with 20 plants inside each experimental plot. The diameter at breast height and total plant height at stand level were obtained by measuring five trees in each experimental unit in seven measurements. During this same period, a flight was carried out using a remotely piloted aircraft for the acquisition of spectral variables (SBs and VIs). For recognition of eucalyptus species in relation to their growth two machine learning approaches were employed: supervised and unsupervised. The average accuracy obtained from 10-fold cross-validation, employing Random Forest algorithm and 24 features, was 0.76. This result shows that the proposed approach is appropriate to recognize different eucalyptus species based on their growth. Universidade Federal de Mato Grosso do Sul (UFMS), Rodovia MS 306, Km. 305 Universidade Estadual Paulista (UNESP), Av. Brasil Sul, 56 – Centro Department of Geography Universidade Estadual de Mato Grosso (UNEMAT), Av. dos Ingas, 3001, Jardim Imperial Universidade Tecnológica Federal do Paraná (UTFPR), Via do Conhecimento – Km 01 Universidade Estadual Paulista (UNESP), Av. Brasil Sul, 56 – Centro

Brazil is one of the world’s biggest emitters of greenhouse gases (GHGs). Fire foci across the country contributes to these emissions and compromises emission reduction targets pledged by Brazil under the Paris Agreement. In this paper, we quantify fire foci, burned areas, and carbon emissions in all Brazilian biomes (i.e., Amazon, Cerrado, Caatinga, Atlantic Forest, Pantanal and Pampa). We analyzed these variables using cluster analysis and non-parametric statistics to predict carbon and CO2 emissions for the next decade. Our results showed no increase in the number of fire foci and carbon emissions for the evaluated time series, whereby the highest emissions occur and will persist in the Amazon and Cerrado biomes. The Atlantic Forest, Pantanal, Caatinga and Pampa biomes had low emissions compared to the Amazon and Cerrado. Based on 2030 projections, the sum of emissions from fire foci in the six Brazilian biomes will exceed 5.7 Gt CO2, compromising the national GHG reduction targets. To reduce GHG emissions, Brazil will need to control deforestation induced by the expansion of the agricultural frontier in the Amazon and Cerrado biomes. This can only be achieved through significant political effort involving the government, entrepreneurs and society as a collective.

Made available in DSpace on 2020-12-12T01:38:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-09-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Universidade Federal do Rio Grande do Sul The stem volume of commercial trees is an important variable that assists in decision making and economic analysis in forest management. Wood from forest plantations can be used for several purposes, which makes estimating multi-volumes for the same tree a necessary task. Defining its exploitation and use potential, such as the total and merchantable volumes (up to a minimum diameter of interest), with or without bark, is a possible work. The goal of this study was to use different strategies to model multi-volumes of the stem of eucalyptus trees. The data came from rigorous scaling of 460 felled trees stems from four eucalyptus clones in high forest and coppice regimes. The diameters were measured at different heights, with the volume of the sections obtained by the Smalian method. Data were randomly separated into fit and validation data. The single multi-volume model, volume-specific models, and the training of artificial neural networks (ANNs) were fitted. The evaluation criteria of the models were: coefficient of determination, root mean square error, mean absolute error, mean bias error, as well as graphical analysis of observed and estimated values and distribution of residuals. Additionally, the t-test (α = 0.05) was performed between the volume obtained in the rigorous scaling and estimated by each strategy with the validation data. Results showed that the strategies used to model different tree stem volumes are efficient. The actual and estimated volumes showed no differences. The multi-volume model had the most considerable advantage in volume estimation practicality, while the volume-specific models were more efficient in the accuracy of estimates. Given the conditions of this study, the ANNs are more suitable than the regression models in the estimation of multi-volumes of eucalyptus trees, revealing greater accuracy and practicality. Federal University of Mato Grosso do Sul (UFMS) College of Agricultural Sciences (FCA) Sao Paulo State University (UNESP) College of Agricultural Sciences (FCA) Sao Paulo State University (UNESP)

The incorporation of the hydrogel into the substrate used in the forest nursery promotes improvements in its physical-chemical attributes. However, several factors influence the hydrogel efficiency, such as the increase of salts, promoted by fertilizer of the substrate. Therefore, this study aimed to evaluate the effects of the incorporation of fertilizer levels and hydrogel doses on the physical-chemical attributes of a substrate to produce forest seedlings. Different levels of basic fertilizer commonly used in the nursery (100%, 50% and 0%) and different doses of the hydrogel (0, 1, 2 and 3 g L-1) were incorporated into the substrate Tropstrato Florestal®, consisting of 12 treatments in a 3 x 4 factorial scheme. A sample of the substrate in each treatment was sent for analysis of its physical and chemical attributes. To evaluate the effect of the treatments on the physical-chemical attributes of the substrate, was used the multivariate principal components analyses. The levels of fertilizer and hydrogel doses were correlated with the attributes of the substrates obtained in each treatment. The incorporation of different fertilizer levels and hydrogel doses to the substrate modified their chemical and physical attributes. Fertilizers have influenced mainly the chemical attributes of the substrate, whereas hydrogels have influenced the physical attributes, mainly those related to water retention capacity and availability. A incorporação do hidrogel ao substrato utilizado no viveiro florestal promove melhorias em seus atributos físico-químicos. Porém vários fatores influenciam na eficiência do hidrogel, como o aumento de sais, promovido pela adubação do substrato. Portanto, este estudo teve como objetivo avaliar os efeitos da incorporação de níveis de adubação e doses de hidrogel sobre os atributos físico-químicos de um substrato para a produção de mudas florestais. Foram incorporados ao substrato Tropstrato Florestal® diferentes níveis da adubação de base comumente utilizada no viveiro (100%, 50% e 0%) e diferentes doses do hidrogel (0, 1, 2 e 3 g L-1), consistindo em 12 tratamentos em esquema fatorial 3 x 4. Uma amostra do substrato em cada tratamento foi encaminhada para análise de seus atributos físicos e químicos. Para avaliar o efeito dos tratamentos sobre os atributos físico-químicos do substrato foi utilizada a análise multivariada de componentes principais. Os níveis de adubação e doses de hidrogel foram correlacionados com os atributos dos substratos obtidos em cada tratamento. A incorporação de diferentes níveis de adubação e doses de hidrogel ao substrato modificaram seus atributos químicos e físicos. A adubação influenciou principalmente os atributos químicos do substrato, enquanto que o hidrogel os atributos físicos, principalmente os relacionados à capacidade de retenção e disponibilidade de água.

A major challenge for the forestry sector is to restore forest cover in degraded areas. In this regard, the adoption of mixed plantations is an opportunity to combine the obtaining of services and products from the forest, providing ecological and socioeconomic advantages. Thus, our objective was to evaluate the growth of native forest species in mixed plantations in Brazilian Savanna. The study was carried out in an area of 4.8 ha with about thirty species planted in spacing 3 × 3 m, located in Chapadao do Sul/MS. At 6.4 years after planting, in 15 randomized plots of 300 m2, the diameter at 1.3 m above ground (DBH), equivalent diameter (DBHeq), total height (H), number of stems (NSI), wood volume (V), biomass (B), carbon (C), and carbon sequestration (CO2) of the trees were measured. Descriptive statistics of the variables were carried out by using boxplot diagrams and principal component analysis (PCA) to group the species according to their growth. The stocks of V and B were 114.03 m3 ha−1 and 52.99 Mg ha−1, respectively. Thus, the mixed planting of native forest species is efficient for recomposing deforested areas, especially as regards biomass accumulation and carbon stock. The species used in mixed planting present different growth form, which were separated by PCA into four groups. DBHeq was the variable that most influenced the differentiation of species into groups. The species Heliocarpus popayanensis, Croton floribundus, Guazuma ulmifolia, Senegalia polyphylla, Enterolobium contortisiliquum, Anadenanthera colubrina, Ceiba speciosa, Anadenanthera peregrina, Gallesia integrifolia and Peltophorum dubium showed the highest growth in the study area.

Este estudo teve como objetivo avaliar o efeito de níveis de sombreamento na produção de mudas de nim indiano (Azadirachta indica), visando a obtenção de mudas com maior padrão de qualidade. Foram adotados quatro tratamentos (pleno sol, 30%, 50% e 70% de sombreamento), dispostos em delineamento inteiramente casualizado, com seis repetições. Os parâmetros avaliados, aos 100 dias, foram: altura da parte aérea, diâmetro do coleto, relação altura/diâmetro, massa fresca e seca da parte aérea, raízes e total, número de folhas e índice de qualidade de Dickson. Os dados foram submetidos à análise de variância, sendo as médias comparadas pelo teste de Duncan a 5% de significância. Mudas produzidas a pleno sol apresentaram maior padrão de qualidade, sendo observados valores mais adequados para os parâmetros diâmetro do coleto, relação altura/diâmetro, massa fresca e seca das raízes, número de folhas e índice de qualidade de Dickson. The purpose of this study was to evaluate the effect of levels of shading on the seedling production of Indian neem (Azadirachta indica), aiming to obtain seedlings with higher quality standard. Four treatments were adopted (full sun; 30%, 50% and 70% of shading), arranged in a completely randomized design, with six replications. The following parameters were evaluated after 100 days: height of the aerial part; root-collar diameter; height/diameter ratio; fresh and dry mass of shoots, roots and total; number of leaves; and Dickson quality index. The data were subjected to analysis of variance and the averages were compared by the Duncan test at 5% significance level. Seedlings produced under full sun showed higher standard of quality, with more suitable values ​​observed for the following parameters: root-collar diameter, height/diameter ratio, fresh and dry mass of roots, number of leaves, and Dickson quality index.

The study of the bole profile is an important tool in the forest production management, which is influenced by several factors, such as the stand conduction regime. This work aimed to evaluate two stand conduction regimes regarding the Eucalyptus urophylla bole in the southwest region of the Brazilian state, Bahia. The data used was retrieved from stands conducted under high forest and coppice regimes. The tapering models proposed by Kozak, Demaerschalk, Ormerod, Garcia and Garay were adjusted, being selected the ones that presented better performances regarding adjustment statistics and graphic analysis of residue for each conduction regime. The models selected were validated by the chi-squared test (α = 0,05). Considering the models selected, it was possible to estimate the value of the diameter along the bole of the average-tree, allowing to evaluate the bole profile for each stand conduction regime. The identity test of the models showed that the stand conduction regime affects the shape of the trees' bole, making a necessity to adjust a specific equation for each situation. The bole tends to present a cylindrical form in a stand conducted in a coppice regime and conical one in a high forest regime. RESUMO O conhecimento do perfil do fuste é em uma ferramenta importante no manejo da produção florestal, sendo o mesmo influenciado por diversos fatores, como o regime de condução do povoamento. O presente trabalho objetivou avaliar a influência de dois regimes de condução do povoamento sobre o perfil do fuste de Eucalyptus urophylla, na região sudoeste da Bahia. Foram utilizados dados de povoamentos conduzidos pelo regime de alto fuste e talhadia. Os modelos de afilamento propostos por Kozak, Demaerschalk, Ormerod, Garcia e Garay foram ajustados, sendo selecionado aquele com melhor desempenho nas estatísticas de ajuste e análise gráfica de resíduos, para cada regime de condução. Os modelos selecionados foram validados utilizando o teste do qui-quadrado (α = 0,05). Diante dos modelos selecionados, foram estimados os valores do diâmetro ao longo do fuste da árvore média, permitindo avaliar o perfil do fuste para cada regime de condução do povoamento. O teste de identidade de modelos mostrou que o regime de condução do povoamento influencia a forma do fuste das árvores, sendo necessário o ajuste de uma equação específica para cada situação. O fuste tende a apresentar forma mais cilíndrica em povoamento conduzido sob regime de talhadia e mais cônica no regime de condução por alto fuste.

Apesar do desenvolvimento técnico e operacional dos viveiros clonais ao longo dos anos, os sistemas de retenção de resíduos e efluentes do processo produziram. O objetivo da pesquisa é avaliar o uso de efluente oriundo de minijardim clonal como adubação em mudas clonais de eucalipto. Foram utilizados os clones AEC 144, GG 100 e VM 01. O experimento foi instalado, o envolvimento de diferentes frequências e lâminas de fertirrigação residual, bem como a utilização da adulação convencional, pelo método de tratamento respiratório, sem uso de Adubação. Para o clone AEC 14, os tratamentos com aplicações diárias de efluente, associados às lâminas de 2 e 3 mm, proporcionaram, em geral, maior qualidade das mudas. Resultado parecido foi observado para o clone VM 01, Em que com o tratamento com aplicação diária e lâmina de 2 mm obteve resultados superiores. O clone GG 100 apresentou mudas de melhor qualidade com três aplicações semanais, independente da lâmina utilizada; Com aplicação diária e lâmina de 3 mm; E com adubação convencional.

The Brazilian Cerrado is the second largest biome in Brazil, and its natural landscapes have undergone transformations, due in large part to anthropic activities. However, little is known about the effects of these activities on the natural regeneration of Cerrado vegetation. Thus, the objective of this study was to evaluate the accumulation of woody biomass in an area of a Cerrado sensu stricto that was monitored for 27 years after the implementation of six silvicultural systems. A period of 17 years was sufficient for the woody community of the Cerrado sensu stricto to naturally recover its original stock of aerial biomass after the application of silvicultural systems. A Few woody species contribute to the total aerial biomass accumulated over time, and such contribution is variable with time and with the type of silvicultural system. At 27 years after cutting, the largest fraction of biomass accumulated in the area were represented by the species Miconia leucocarpa, Blepharocalyx salicifolius, Schefflera macrocarpa, Qualea grandiflora, Dalbergia miscolobium, Eriotheca pubescens, Qualea parviflora and Caryocar Brasiliense, which also demonstrated higher fire resistance. A period of 17 years after the implementation of silvicultural systems is considered sufficient for an area to recover naturally to the original stock of woody biomass at the community level. This result causes a greater reduction in the biomass of fire-sensitive species and transforms a Cerrado from a carbon sink into a source of CO2 emissions to the atmosphere.

EFEITO DE DOSES DO HIDROGEL NA QUALIDADE DE MUDAS DE Corymbia citriodora Hill & Johnson O objetivo deste estudo foi avaliar a influencia de diferentes doses do hidrogel, incorporado ao substrato, na producao de mudas de eucalipto citriodora ( Corymbia citriodora ). Foi considerado o delineamento inteiramente casualizado com 5 tratamentos (0, 1, 2, 3 e 4 g L-1 doses do hidrogel) e 5 repeticoes. Para tanto, foram produzidas mudas (via sementes) em tubetes de 55 cm3, com diferentes doses do hidrogel incorporado ao substrato. Aos 120 dias apos a semeadura, a qualidade das mudas foi avaliada por: altura da parte aerea, diâmetro do coleto, massas secas, da parte aerea, das raizes e total e indice de qualidade de Dickson. Os dados foram submetidos a analise de variância da regressao por polinomios ortogonais (α = 0,05), sendo selecionada a equacao correspondente a regressao de mais alto grau que foi significativa (p < 0,05). Apenas a altura e as massas secas da parte aerea e total apresentaram respostas significativas as doses do hidrogel. A dose intermediaria (2 g L-1) foi a que promoveu melhor qualidade as mudas, proporcionando incrementos superiores a 10% para todas as variaveis analisadas. Dessa forma, a incorporacao do hidrogel ao substrato contribui para o maior crescimento e padrao de qualidade de mudas de Corymbia citriodora . Palavras-chave: polimero hidroretentor, viveiros florestais, eucalipto. ABSTRACT The aim of this study was to evaluate the influence of different hydrogel doses incorporated into the substrate in the production of lemon-scented gum seedlings ( Corymbia citriodora ). The design was entirely randomized with 5 treatments (0, 1, 2, 3 and 4 g L-1 hydrogel doses) and 5 repetitions. Therefore, seedlings were produced (via seeds) in 55 cm3 tubes, with different doses of hydrogel incorporated into the substrate. At 120 days after sowing, the seedlings quality was evaluated by: shoot height, stem diameter, shoot, root and total dry mass and Dickson quality index. The data were submitted to regression analysis of variance for orthogonal polynomials (α = 0.05), being selected the corresponding equation for the highest degree of regression that was significant (p < 0.05). Only the shoot and total height and dry mass showed significant responses to the hydrogel doses. The intermediate dose (2 g L-1) promoted the best quality to seedlings, providing increments greater than 10% for all variables. Thus, the incorporation of the hydrogel to the substrate contributes to increased growth and quality standard of Corymbia citriodora seedlings. Keywords: hydroretentive polymer, forest-tree nurseries, eucalyptus. DOI: http://dx.doi.org/10.14583/2318-7670.v04n04a10

Este trabalho avaliou a produção de mudas de Handroanthus ochraceus (Cham.) Mattos submetidas à diferentes doses de hidrogel e adubação nitrogenada em viveiro. O experimento foi instalado em delineamento inteiramente casualizado, em um fatorial com cinco concentrações de hidrogel (0 a 4 g) e seis de adubação (0 a 5 g), totalizando 30 tratamentos e cinco repetições compostas por quatro mudas. Foram avaliados altura, diâmetro do coleto, número de folhas, massa seca da parte aérea, de raiz e total, relações entre altura/diâmetro do coleto, altura/massa seca da parte aérea, parte aérea/raiz, índice de qualidade de Dickson e incremento em altura e diâmetro em três etapas. Os dados foram submetidos à análise de variância (p < 0,05) e regressão. Os diferentes tratamentos geraram respostas distintas e, no geral, influenciaram positivamente o crescimento e a qualidade das mudas. Os 80 dias iniciais sob sombra proporcionaram maior crescimento em altura e diâmetro das mudas. This study evaluated the production of seedlings of Handroanthus ochraceus (Cham.) Mattos submitted to different doses of hydrogel and nitrogen fertilization in greenhouse. The experiment was conducted in a completely randomized design in a factorial with five concentrations of hydrogel (0 to 4 g) and six fertilization treatments (0 to 5 g), totaling 30 treatments and five replicates composed of four seedlings. We evaluated height; stem diameter; number of leaves; dry mass of shoot and root; total dry mass; ratios between height/diameter, height/shoot dry mass, and shoot/root; Dickson quality index; and increase in height and diameter in three steps. Data were submitted to analysis of variance (p < 0.05) and regression. The different treatments have generated different responses and, in general, positively influenced the growth and quality of seedlings. The initial 80 days under shade provided greater growth in height and diameter of seedlings.

Accurate estimation of biomass in natural vegetation sites remains a challenge. Modeling biomass growth and production in Cerrado areas is crucial to understanding the vegetation succession process, especially regarding the changes in biomass accumulation over time. Thus, our objective was to model the growth and production of woody aboveground biomass (living and total) in a cerrado stricto sensu monitored for 27 years after implementing management systems. As expected, the basal area (with a diameter taken at 30 cm from the ground level) is the most important predictor variable and showed a higher correlation with the biomass stocks and allowed accurate and consistent estimates of these accumulated stocks over time. Future estimates of biomass production, generated from growth models that estimate production as a function of parameters observed at previous ages, indicate that maximum stocks of living (25.86 ± 0.15 Mg ha−1 [mean ± standard deviation]) and total aboveground biomass (26.11 ± 0.15 Mg ha−1) are expected for a period between 28 and 30 years after the implementation of the management systems, with maximum mean annual increment between 23 and 27 years. Furthermore, the systems of equations obtained simulated reductions up to 30% of biomass after the occurrence of a forest fire at 23 years. Thus, our study can be useful for the decision-making process and developing public policies and strategies for managing and conserving natural resources in the Cerrado biome. Made available in DSpace on 2021-10-15T14:02:04Z (GMT). No. of bitstreams: 1 Prognosis-of-aboveground-woody-biomass-Fabiana.pdf: 5589740 bytes, checksum: bb45d5d6f5821616def6eac0fe2572fa (MD5) Previous issue date: 2021