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Nas últimas décadas, a demanda crescente por madeiras tropicais no mundo tem levado ao surgimento de práticas desenvolvidas à Gestão da Qualidade no setor florestal, em que a amostragem do trabalho tem se destacado entre os métodos de medição das atividades produtivas capazes de promover formas de padronização das operações que visam à eficiência da mão de obra e maquinário. Portanto, este trabalho tem o objetivo de avaliar o desempenho operacional no desdobro de espécies nativas, por meio da amostragem do trabalho realizada nas operações de serra de fita em duas serrarias de pequeno porte situadas no município de Pacajá, Pará. Os dados foram obtidos através da observação direta e sistemática, cronometrados em intervalos intermitentes de três minutos nas atividades de desdobro de toras, totalizando 480 amostras para cada processadora, durante seis dias de levantamento. A serraria I desdobrou somente a espécie Ipê Amarelo (Handroanthusserratifolius (Vahl) S.O. Grose), e obteve 68,23% de tempo médio produtivo. A serraria II utilizou a Maçaranduba (Manilkara amazônica (Huber) Standl.) como principal espécie, e alcançou 74,39% de produtividade do trabalho. Tal resultado, justificou-se pela maior frequência e duração dos intervalos para alívio da fadiga e necessidades pessoais dos operadores da serraria II, o que possibilitou a recuperação física e maior disposição ao trabalho.

The heartwood formation process is little known in fast growing plantation woods. Therefore, the aims of this study were to determine how planting spacing and tree age affect the formation and proportion of heartwood and sapwood, as well as the density of eucalyptus wood. Trees from a eucalyptus clonal plantation (Eucalyptus grandis × E. urophylla hybrid) cultivated in three spacings (3 × 1, 3 × 2 and 3 × 3 m) were sampled at 14, 27, 32, 53, 64 and 76 months of age. Heartwood percentage was quantified with Dimethyl yellow indicator, while the wood density was determined by X-ray densitometry. The heartwood percentage, wood volume, heartwood density and wood density were correlated with the different growth rates. The heartwood formation process started between 32 and 53 months, regardless of spacing. The heartwood proportion doubled with increasing age in the widest spacing and increased about four times in 3 × 1 and 3 × 2 m spacing. The planting spacing influenced the growth rates of the trees, but did not affect the heartwood and sapwood percentage or density. The greatest increase in density values occurred between the first year of growth (14 months) and the beginning of heartwood formation (53 months).

Sewage sludge is a byproduct of wastewater treatment. When processed, this residue can also be used as adsorbent. The aim of this study was to produce adsorbents from the sewage sludge, characterize its structure and evaluate the efficiency in adsorption of lipophilic wood compounds. The sewage sludge was calcinated at seven temperatures (400-1000°C) for five hours. The morphology and texture properties of the materials were evaluated by scanning electron microscopy and nitrogen isotherms. The presence of chemical functional groups at their surface was analyzed by Fourier transformed infrared spectroscopy. Lipophilic compound adsorption rate was evaluated by gas chromatography-mass spectrometry. The results were compared with talc, an adsorbent traditionally used by the industry. The increase in temperature directly contributed to a decrease in the specific surface area. The adsorbents obtained between 600 and 700°C removed more than 60% of the lipophilic wood compounds, corresponding to 94.1% of the total amount of lipophilic compounds. These values are much higher than those presented by talc, being 2 and 11.8%, respectively. Therefore, the produced adsorbents can be studied as a new material in the removal of lipophilic wood compounds : O lodo de esgoto é um subproduto do tratamento de efluentes. Quando processado, este resíduo também pode ser usado como adsorvente. O objetivo deste trabalho foi produzir adsorventes a partir do lodo de esgoto, caracterizar sua estrutura e avaliar a eficiência na adsorção de compostos lipofílicos de madeira. O lodo de esgoto foi calcinado a sete temperaturas (400- 1000°C) por cinco horas. As propriedades de morfologia e textura dos materiais foram avaliadas por microscopia eletrônica de varredura e isotermas de nitrogênio. A presença de grupos funcionais químicos em sua superfície foi analisada por espectroscopia de infravermelho por transformada de Fourier. A taxa de adsorção do composto lipofílico foi avaliada por cromatografia gasosa -espectrometria de massa. Os resultados foram comparados com o talco, adsorvente tradicionalmente utilizado pela indústria. O aumento da temperatura contribuiu diretamente para a diminuição da área superficial específica. Os adsorventes obtidos entre 600 e 700°C removeram mais de 60% dos compostos lipofílicos da madeira, correspondendo a 94,1% da quantidade total de compostos. Esses valores são muito superiores aos apresentados pelo talco, sendo 2 e 11,8%, respectivamente. Portanto, os adsorventes produzidos podem ser estudados como um novo material na remoção de compostos de madeira lipofílicos.

The variable environmental conditions of the Amazon forest can affect the wood properties of the tree species distributed across its diverse phytophysiognomies. Carapa guianensis (Andiroba) occurs in upland and floodplain forests, and the wood and oil of its seeds have multiple uses. The aim of this study was to evaluate the wood properties of C. guianensis trees in upland and estuarine floodplain forests of the Amazon River. Eight trees were selected, with four being from the upland and four from the floodplain forests. The fiber length, fiber wall thickness, vessel diameter and frequency, microfibril angle, specific gravity and wood shrinkage were evaluated. The juvenile and mature wood zones were determined according to these variables. The fiber length, fiber wall thickness and specific gravity increased, and microfibril angle decreased, in the pith to bark direction. Only the fiber length variable was efficient for delimiting juvenile, transition and mature wood. The fiber length, wall thickness and specific gravity of wood were higher in upland forest trees. However, the environment did not alter the beginning of the formation and proportion of C. guianensis mature wood. This information is important for the log fit in cutting diagrams, aiming toward improving the production, classification and processing of pieces with specific quality indexes in order to direct them to appropriate wood uses. Made available in DSpace on 2019-11-14T18:29:29Z (GMT). No. of bitstreams: 1 CPAFAP2019WoodpropertiesofCarapa.pdf: 1669509 bytes, checksum: afc781687121e3c321b8c419e5406b09 (MD5) Previous issue date: 2019

The increase in global temperature results in changes in rainfall patterns and can cause structural and functional changes in trees. Each plant is forced to face hydraulic safety limits and adopt a behavior to regulate its water status. The objective of this work was to evaluate the changes in the hydraulic architecture of the xylem of commercial eucalyptus clones in order to distinguish the hydraulic adjustments in a wide gradient of water availability. Eucalyptus urophylla (A1) and E. grandis × E. camaldulensis (C3) clones at six years old at 4 sites in Brazil distributed in a rainfall gradient and in two water conditions were analyzed: control (100% of total local rainfall) and rainfall reduction (RR). Xylem traits were evaluated at annual intervals and averaged over the entire growth period of the seven trees sampled at each site and water condition. The sites influenced the clones, with the greatest effect being the rainfall reduction treatment in C3 on the vessel wall diameter, area and thickness, double wall thickness, conduction area, vessel composition index, theoretical and potential hydraulic conductivities, vessel implosion resistance and vulnerability. The rainfall reduction provided an increase of 12% in vessel density, 8% in the double vessel wall, and 27% in theoretical hydraulic conductivity in the drought-tolerant C3 clone. The vessel wall thickness in the A1 clone was more responsive with a 3% increase in rainfall reduction, with an effect on double-wall thickness and vessel implosion resistance. Other hydraulic adjustment strategies were observed, such as the highest occurrence of tylose and a tradeoff between vessel diameter and frequency for the C3 clone. The greater variation in wood density was explained by variations in the lumen area of the xylem vessels and by vessel implosion resistance.

Neutral sulphite semichemical pulping (NSSC) of Schizolobium amazonicum (Paricá), a fast-growing Amazonian tree, was compared with that of Eucalyptus grandis (eucalypt), one of the most important wood sources for the Brazilian pulp industry, and with mixtures of both woods in different proportions (mix). Wood chips prepared from 7-year old trees were steamed, cooked using the NSSC process and defibered in a 12” disc refiner in three stages. The paricá wood produced pulp of lower yield (75 %) than eucalypt (77 %) at 16 % sulfite/150 min/170 °C. The paricá and eucalypt pulps were bleached to about 68 and 74 % ISO brightness, respectively, by the QPFAS sequence. Paricá consumed more energy for refining in comparison with the eucalypt wood. The wood mix produced lower yield and brightness than the single species processed separately.

CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior Outra Agência The Brazilian Savannah, known as Cerrado, has the richest flora in the world among the savannas, with a high degree of endemic species. Despite the global ecological importance of the Cerrado, there are few studies focused on the modeling of the volume and biomass of this forest formation. Volume and biomass estimation can be performed using allometric models, artificial intelligence (AI) techniques and mixed regression models. Thus, the aim of this work was to evaluate the use of AI techniques and mixed models to estimate the volume and biomass of individual trees in vegetation of Brazilian central savanna. Numerical variables (diameter at height of 1.30 m of ground, total height, volume and biomass) and categorical variables (species) were used for the training and fitting of AI techniques and mixed models, respectively. The statistical indicators used to evaluate the training and the adjustment were the correlation coefficient, bias and Root mean square error relative. In addition, graphs were elaborated as complementary analysis. The results obtained by the statistical indicators and the graphical analysis show the great potential of AI techniques and mixed models in the estimation of volume and biomass of individual trees in Brazilian savanna vegetation. In addition, the proposed methodologies can be adapted to other biomes, forest typologies and variables of interest.

The intensity of climate changes demands studies on the adaptability of the most planted eucalyptus genetic materials in the world, such as E. urophylla and E. grandis × E. camaldulensis which were evaluated in this study. The objective of this work was to evaluate wood traits and to relate it to the meteorological variables for each year of growth of the trees that grew in four sites with different climatic conditions and 33% rainfall exclusion. The wood traits evaluated were: wood density, vessel density, diameter and area, vessel wall thickness, total vessel wall thickness between adjacent cells, theoretical hydraulic conductivity, potential hydraulic conductivity, lumen conductivity area, vessel composition within space, vessel implosion resistance and vulnerability index to drought. Pearson’s correlations between the evaluated variables were estimated and the results expressed graphically through the correlation network. Multiple regression analysis with adjustment by the Exhaustive Search method was used to estimate the vessel wall thickness in order to isolate this characteristic and identify the explanation intensity of the meteorological variables. Pearson’s correlations between meteorological factors and wood traits show different interactions in the behavior of the clones and in the water availability conditions. Air temperature was present in all the vessel wall thickness estimation equations. The 33% rainfall exclusion provided the best equation adjustments with meteorological variables, explaining up to 84% of the variation in the vessel wall thickness. The rainfall exclusion intensified the effects of the interrelations between climate and hydraulic architecture in E. grandis × E. camaldulensis, with implosion resistance and vessel wall thickness having a strong relationship between climate and wood. The results of rain reduction in the dynamics between wood and climate have implications for indirect selection in breeding programs.

The wood production potential that a site presents is largely represented by its climatic condition and by the affinity of its genetic material. An issue which concerns all wood producers is climate change and how it will influence wood production and wood characteristics, as they can be decisive in industrial applications. Therefore, this study aimed to: (i) verify the wood volume (WV), stem biomass (SB) and the basic wood density (BWD) behavior against different climatic scenarios; and (ii) verify the potential of estimating the BWD through meteorological variables. The WV, BWD and SB of four different Eucalyptus spp. clones as to their climate of origin and species were analyzed. The cultivation was from 2012 to 2015 (four years) with planting in 11 locations in Brazil, representing a wide range of climatic characteristics with average precipitation from 649 mm y−1 to 1618 mm y−1. Precipitation, maximum vapor-pressure deficit, water deficit in the soil, temperature and precipitation seasonality were used to characterize the regions during the growth period. Hierarchical grouping was carried out for the sites, and the WV, BWD and SB behavior within the groups were analyzed. Thus, a linear regression equation between the most influential meteorological variables in the BWD were adjusted in order to identify the potential of the estimative BWD. Four groups were formed between the sites, and the variation in WV, BWD and SB for each clone between the wet and dry groups were respectively: C3: −68.3%, +8.7% and −65.0%; K2: −77.5%, +8.3% and −74.3%, A1: −40.3%, −9.21% and −39.9%; and Q8 – −31.6%, +8.4% and −34.1%. The drier locations generally showed lower WV and SB, and higher BWD associated to a decrease in the growth rate. This behavior is intrinsic to each clone and does not establish a defined proportion. Humid locations did not show clear patterns in changing density. The maximum vapor-pressure deficit and the water deficit in the soil were the most significant variables and had the best potential to estimate the basic wood density of the wood. Basic wood density is a resource which can be strongly influenced by genetics, and above all there is a significant influence of climate on the sites.

One of the forms used to differentiate wood is heartwood and sapwood classifications, as variations in the proportions influence wood use. The aim of this study was to compare the heartwood percentage (H%) and wood density (WD) of eucalyptus in plantations along a climatic gradient, and to estimate these characteristics using meteorological variables and tree growth rate. E. urophyla clones at 6 years old were analyzed in 12 sites distributed across a wide geographic variation in Brazil. Seven trees from each site were sampled, and a disc was taken from the DBH position. H% was determined by image analysis, while heartwood density (HD), sapwood density (SD) and wood density (WD) by X-ray densitometry. H%, HD, SD and WD data were submitted to analysis of individual variance and the sites means were compared. WD and H% were correlated with the following variables: temperature (T), precipitation (P), soil water deficit (SWD), water use index (W), water use efficiency (WUE) and mean annual increment (MAI); these variables were also used in the multiple regression analysis in the adjustment of equations. The differentiation between heartwood and sapwood by color was possible in all sites. The sites located in higher and more humid latitudes presented the highest H% values (between 61 and 67%). In general, HD was lower than SD, with the sites with the lowest MAI values showing the lowest SD values, and wet sites with higher MAI and the highest densities. H% showed strong and significant correlations with T, P, SWD, W and MAI, whereas HD only showed moderate and significant correlations with T, MAI and WUE. The best equation for estimating H% used the P and MAI variables, which managed to explain 79% of the variation. In the WD estimation, the best equation only used the WUE variable and obtained an explanation power of 53%. In addition to the strong relationship between heartwood percentage and growth, it was found that the climate also influences heartwood formation. Use the equation obtained for clone A1 in other clones confirmed that the response variability for wood properties is also influenced by genetic. No relationship was observed between the Huber value and climatic conditions, however, the factors influencing SA:LA ratio behavior are complex and requires considering other components. H% was shown to be more correlated with climate than density, and the observed variability between sites suggests the inclusion of heartwood content assessments in this species in management and breeding programs.

O lodo de esgoto é um subproduto do tratamento das águas residuárias, e sua disposição final pode se tornar um problema ambiental. O preparo de adsorventes é considerado um método atrativo de reúso desse subproduto. Adsorventes obtidos a partir do lodo de esgoto ainda não foram utilizados na remoção de compostos lipofílicos da madeira. Esses compostos são precursores do pitch, material resinoso que, quando formado, ocasiona prejuízos às indústrias de celulose e papel. O lodo de esgoto foi utilizado para preparo de adsorventes a partir da calcinação em sete temperaturas (400, 500, 600, 700, 800, 900 e 1000 ºC) durante cinco horas. Foram avaliadas as propriedades de morfologia e área superficial específica dos adsorventes. Os adsorventes foram utilizados no estudo de adsorção de compostos lipofílicos da madeira e os resultados foram comparados com o talco. A observação de fotografias da superfície obtidas por microscopia eletrônica de varredura revelou a presença de poros e cavidades na superfície dos adsorventes. As isotermas de adsorção foram classificados, segundo a IUPAC, como tipo IV e histerese H3, corroborando a presença de mesoporos. A correlação entre a temperatura de calcinação e a área superficial BET, que variaram de 0,73 - 23,4 m2g-1 foi evidenciada, e, com aumento na temperatura de calcinação, promoveu decréscimo nos valores de área superficial. Os adsorventes obtidos por calcinação entre 400 e 800 ºC apresentaram valores de SBET superiores ao talco (5,25 m2 g-1), e aqueles produzidos a 600 e 700 ºC apresentaram maior potencial de adsorção (94%), enquanto o talco removeu 11,8% dos extrativos. O adsorvente produzido a 700 ºC foi utilizado no estudo da adsorção de quatro compostos que representam as principais classes químicas presentes nos extrativos da madeira (dodecan-1-ol, ácido hexadecanoico, tetracosano, -sitosterol). Foram otimizados tempo de adsorção, quantidade de adsorvente e concentração inicial do adsorbato. As condições otimizadas foram utilizadas para avaliação do tempo de preparo do adsorvente e, em seguida, a condição com melhor resultado foi empregada na calcinação de amostras de lodo de esgoto de dez cidades (Bambuí, Belo Horizonte, Bom Despacho, Claro dos Poções, Corinto, Curvelo, Janaúba, Montes Claros, Porteirinha e Taiobeiras). Para tempo de contato, foram otimizado 30 minutos de agitação e para dosagem de adsorvente de 0,2 g. As isotermas de adsorção apresentaram classificação H, segundo Giles (1960), indicando alta afinidade dos compostos pelo adsorvente. A diminuição no tempo de calcinação dos adsorventes não provocou redução na eficiência de adsorção, além de diminuir os gastos energéticos de produção. A porcentagem de remoção dos compostos pelos adsorventes produzidos a partir do lodo das dez cidades foi superior a 70%, exceto para a adsorção de tetracosano pelo adsorvente referente à cidade de Claro dos Poções. As melhores taxas de adsorção (acima de 85 %) foram obtidas pelos adsorventes a partir do lodo de esgoto das cidades de Belo Horizonte, Bom Despacho, Corinto, Curvelo e Montes Claros. Os resultados obtidos evidenciaram a eficiência do adsorvente na remoção de compostos lipofílicos presentes nos extrativos da madeira e, consequentemente, no pitch. Sewage sludge is a byproduct of the wastewater treatment and its final disposal can become an environmental problem. The preparation of adsorbents is considered an attractive method of reuse of this byproduct. Adsorbents obtained from sewage sludge have not yet been used in removing of lipophilic compounds of the wood. These compounds are precursors of the pitch, resinous materials that, when formed, cause economic losses to the pulp and paper industries. Sewage sludge was used to prepare adsorbents from calcination at seven temperatures (400, 500, 600, 700, 800, 900 e 1000 ° C) for five hours. The properties of morphology and specific surface area of the adsorbents were evaluated. The adsorbents were used on the adsorption study of lipophilic compounds of the wood and the results were compared to talc. The observation of photographs of the surface obtained by scanning electron microscopy revealed the presence of pores and cavities on the surface of the adsorbents. The adsorption isotherms were classified, according to the IUPAC, as type IV and H3 hysteresis, corroborating the presence of mesopores. The correlation between calcination temperature and the BET surface area, which ranged from 0,73 to 23,4 m2g-1, was evidenced, and with an increase in calcination temperature promoted a decrease in the surface area values. Adsorbents obtained by calcination between 400 and 800 ºC presented SBET values higher compared to talc (5,25 m2 g-1) and those produced at 600 and 700 ºC presented greater adsorption potential (94%), while talc removed 11.8% of extractives. The adsorbent produced at 700 ° C was used on the adsorption study of four compounds that represent the major chemical classes present on wood extractives (dodecan-1-ol, hexadecanoic acid, tetracosane, -sitosterol). The adsorption time, adsorbent quantity and the adsorbat initial concentration were optimized. The optimal conditions were used in order to evaluate the adsorbent preparation time, and,after that, the condition with the best result was used for the calcination of sewage sludge samples from ten cities (Bambuí, Belo Horizonte, Bom Despacho, Claro dos Poções, Corinto, Curvelo, Janaúba, Montes Claros, Porteirinha e Taiobeiras). For contact time were optimized 30 minutes of stirring and to the adsorbent dosage of 0.2 g. The adsorption isotherms presented classification H, according to Giles (1960), indicating high affinity of the compounds by the adsorbent. The decrease in the calcination time of the adsorbing did not cause reduction in adsorption efficiency, besides reducing the energetic costs of production. The percentage removal of compounds adsorbents produced from sludege from ten cities was above 70%, except for the adsorption of tetracosane by the adsorbent concerning to the city Claro dos Poções. The best adsorption rates (greater than 85 %) were obtained by adsorbents from sewage sludge of the cities in Belo Horizonte, Bom Despacho, Corinto, Curvelo and Montes Claros. The obtained results evidenced the efficiency of the adsorbent in removal of lipophilic compounds present in wood extractives and, consequently, pitch.

A expansão das áreas para o cultivo de grão-de-bico depende da produção de sementes detentoras de qualidade superior. Neste trabalho, foram avaliadas as principais características físicas, fisiológicas e sanitárias em sementes de seis genótipos de grão-de-bico produzidas em Montes Claros, Norte de Minas Gerias. As variáveis analisadas foram o grau de umidade, a pureza física, a massa de mil sementes, a uniformidade, a porcentagem de germinação, a primeira contagem do teste de germinação, o índice de velocidade de germinação e de emergência, a massa seca da parte aérea das plântulas e a ocorrência de microrganismos e de pragas de armazenamento nas sementes. A qualidade física, fisiológica e sanitária das sementes foi afetada pelos diferentes genótipos de grão-de-bico analisados. As variações quanto à qualidade física das sementes entre os genótipos de grão-de-bico não estão relacionadas à qualidade fisiológica e sanitária destas. De maneira geral, as sementes do genótipo CNPH 08-04 apresentaram qualidade física, fisiológica e sanitária superior à qualidade das sementes dos demais genótipos.