Ciência Florestal

(998 Artigos indexados)

MINIESTAQUIA DE ERVA-MATE EM QUATRO ÉPOCAS DO ANO - (2018)

Francielen Paola de Sá, Deborah Cristina Portes, Ivar Wendling, Katia Christina Zuffellato Ribas

Volume: 28 - Issue: 4

Resumo. Ilex paraguariensis is a forest species that has multiple potentialities, being used in the food, pharmaceutical and cosmetic industries. However, the seminal propagation of the species is difficult due to its low (below 20%) and non-uniform germination and the long period (four to six months) stratification of seeds needed for the breaking of embryo dormancy. The minicutting technique is an alternative to overcome such limitations, therefore this study aimed to evaluate the effect of indolebutyric acid (IBA) on rooting of yerba mate minicuttings collected at different seasons (July/2014 to May/2015). Minicuttings were prepared with 6 cm (± 1 cm) long and two leaves reduced by half and, the basal portion of the propagules was immersed for 10 second in different hydroalcoholic solutions of IBA (0,200,400,6000 and 8000 mg L-1). After 90 days of installation of the experiments, we evaluated the percentage of rooting, root number and average length of three major roots, percentage of callogenesis, leaf retention, developed shoots and mortality. The spring was the most promising season, providing approximately 70% of rooting and coupled the application of 8000 mg L-1 of the IBA the minicuttings reached the greatest length (4.3 cm) and root number (9.1) as well as the lower callus induction rate (0%). The minicutting collection in the spring and 8000 mg L-1 of the IBA is the most indicated for minicutting technique of yerba mate.

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MODELOS ARQUITETÔNICOS PARA AS ESPÉCIES ARBÓREAS DE UMA FLORESTA ESTACIONAL SUBTROPICAL NO RIO GRANDE DO SUL - (2018)

Malcon do Prado Costa, Solon Jonas Longhi

Volume: 28 - Issue: 4

Resumo. Architectural models contribute to describe the development and the arrangement of the tree canopy. This knowledge is crucial for the understanding of the behavior of forest trees and it may also help us understand the evolutionary relationships among the taxa. This study is aimed at identifying how rich the architectural models of the arboreal species of a seasonal forest are. The data was gathered from field observations and specialized literature. It presents a list of 53 tree species from the tree flora of the Subtropical Seasonal Forest of the Santa Maria - RS, distributed in 45 genera and 28 families in the tree flora. A total of 13 different architectural models have been recognized. The most prominent models were Rauh, Troll, Scarrone, Roux and Massart. The architectural complexity, reflected by the high number of models described, is due to the development of the canopy in the rest of the study. This work had a pioneering and exploratory character and shall provide a framework for new studies on plant architecture in the subtropical region of Brazil.

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MORPHOLOGICAL AND STRUCTURAL CHARACTERIZATION OF BAMBOO FIBER INTO CULM - Guadua angustifolia KUNTH - (2018)

Luz Adriana Sánchez Echeverri, Mario Enrique Rodríguez García

Volume: 28 - Issue: 4

Resumo. Studies about lignocellulosic materials have gained importance in the last decades due to the outstanding characteristics that their fibers offer, which becomes in a good alternative to replace synthetic fibers. Lignocellulosic materials such as bamboo have high availability in most of regions around the world due to the adaptation capacity to grow in different areas and diverse climatic conditions. Despite of this fiber has being widely used; their microstructural organization into the culm has not been fully studied. The focus of this research is to study the morphology, distribution and crystalline compounds of fiber in native Colombian Bamboo called Guadua angustifolia Kunth for two varieties Rayada Amarilla and Macana. Scanning electron microscopy was used to observe Guadua fiber morphology and their variation throughout the culm, X-ray diffraction was used to identify crystalline compounds present in Guadua angustifolia Kunth and AOAC-2000 methodology (Association Official Agricultural Chemist) was used to get quantitative information about the insoluble and soluble fiber content into Guadua culm. Findings indicated that the insoluble fiber distribution is not homogenous between the internal and external layer of bamboo culm; the fiber content inside of Guadua angustifolia culms increases from inner to outer layer. X-ray patterns showed that the insoluble fiber has a preferential crystalline orientation in relation to the growth direction of bamboo. The combination of scanning electronic microscope and X-ray diffraction offers important information about the localization and morphologic distribution of components inside bamboo culms.

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NUTRIENTES E UMIDADE DO SOLO APÓS A INCORPORAÇÃO DE BIOCARVÃO EM UM PLANTIO DE Eucalyptus benthamii - (2018)

Thiago Woiciechowski, Kátia Cylene Lombardi, Flávio Augusto de Oliveira Garcia, Gabriela Schmitz Gomes

Volume: 28 - Issue: 4

Resumo. The objective of this research was to evaluate the nutritional and moisture conditions of a soil cultivated with Eucalyptus benthamii, in which it was used biochar coming from the fast pyrolysis of a mixture of native species of Mixed Ombrophilous Forest in the preparation of the pre-planting. The study was developed in an experimental area of the State University of the Center-West located in Irati, Paraná state. Four doses of biochar, 0, 10, 20 and 40 Mg ha-1, with and without mineral fertilization of 340 Kg ha-1 of NPK with 14 Kg N, 48 Kg P2O5, 28 Kg K2O in formulation 4-14-8, in a randomized complete block design with four replicates. Eucalyptus benthamii seedlings were planted in spacing 3 x 2 meters and, after 60 and 180 days, the following soil attributes were evaluated: pH, organic carbon, P, K, Ca, Mg, Al contents and soil moisture. The application of 40 Mg ha-1 biochar with and without basic fertilization, caused an increase of pH and nutrients due to the ash content in the constitution of the conditioner, and an increase of the soil moisture. The application of biochar may become a positive practice in order to provide nutrients for the initial development of the crop. However, it is necessary to evaluate the effect of fertility according to the dose applied, since the availability of nutrients may decrease over time, leading to the need for cover fertilization, however in smaller amounts.

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OCORRÊNCIA DE RAÍZES GEMÍFERAS EM Tabebuia roseoalba (Ridl.) Sandwith (BIGNONIACEAE, LAMIALES) - (2018)

Jales Teixeira Chaves Filho, Jácomo Divino Borges

Volume: 28 - Issue: 4

Resumo. The species Tabebuia roseoalba, present in the native flora of cerrado, exhibits vegetative propagation in the natural environment. The presence of underground systems that produce buds in woody tree species is related to survival under environmental disturbances. Thus, the aim of this work was to analyze and characterize anatomically the underground system producing shoot-buds in the Tabebuia roseoalba species. The material used in the investigation (plagiotropic roots) were cut into ten centimeters long segments, rinsed with water and planted in plastic pots with vermiculite. The segments were kept in a thermostatic chamber during 60 days. After, the material was hand sectioned and then stained with safranin and methylene blue for the microscopic examination. The results indicate that the underground system analyzed has a characteristic arrangement of roots with the protoxylem poles on the outer side (exarch) and the center of the structure is made up entirely of xylem. The characteristics observed in this work lead to propose that the buds are reparative in which their formation is linked to any environmental disturbance in the underground system.

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PERFIL DOS FRAGMENTOS DE MATA ATLÂNTICA COM REGISTROS DO MUTUM-DO-SUDESTE - (2018)

Elaine Rios, Poliane Farias Santos, Christine Steiner São Bernardo

Volume: 28 - Issue: 4

Resumo. Assessing the effects of land use change on biodiversity has become a key issue for species conservation. Thus, it is necessary to analyze the configuration and composition of the landscape where a species occurs. The objective was to draw a profile of the forest remnants of the Atlantic Forest located in the south of Bahia state that present current and historical records of Crax blumenbachii. We analyzed fourteen areas using different spatial scales (patch scale, 500 m, 1 and 2 km) to calculate the total distance and distance from roads and rivers to the edge of the patch, percentage of area occupied by: forest, forest with cabrucas, cabrucas, pasture and agriculture; density of fragments and the proximity of these fragments to the edge of each patch, the area occupied by houses and their distance to the edge of the patch. We selected the 2 km scale to best describe the configuration and composition of the landscape. There are two profiles of areas with records of red-billed curassows: (1) areas with more forested landscapes, rivers and roads, low pasture/agriculture, and near human settlements, and (2) areas distant from houses, near roads and forest fragments. These features are related to areas with recent or historic records of red-billed curassows, and do not necessarily reflect habitat quality for the species.

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PERFORMANCE ASSESSMENT OF METHODOLOGIES FOR VERTICAL STRATIFICATION IN NATIVE FORESTS - (2018)

Edvaldo Nogueira Sousa Neto, Alessandro de Paula, Cristiano Tagliaferre, Patrícia Anjos Bittencourt Barreto Garcia, Dalton Longue Júnior

Volume: 28 - Issue: 4

Resumo. Vertical stratification - as well as other environmental phytosociological parameters for uneven-aged stands in forest structures - is one of the factors that regulates the amount of energy present in a forest, although it is often disregarded. The objective of this study is to evaluate the performance of some commonly used methodologies to characterize the vertical stratification of a forest fragment. Researchers from UESB - State University of Southwest Bahia collected data in a Seasonal Forest fragment located in the city of Vitória da Conquista, Bahia, Brazil. The standard method used in the study was the Sociological Position Method. Results were compared to six other methods: IUFRO; Vega; Longhi; Calegário; Souza and Leite; and Hasenauer. The performance of each method was assessed according to the “c” coefficient. Results of the standard method showed 954 individuals (656 dominant; 232 codominant; and 66 dominated). The “c” coefficient was found to be efficient to interpret the performance of these methods. The IUFRO Method showed the best performance when compared to the Sociological Position Methods.

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PERÍODOS DE SECAGEM NA QUALIDADE FISIOLÓGICA DE SEMENTES DE Licania rigida Benth - (2018)

Eliane Duarte Brandão, Manoel Alexandre Diniz, Luciana Rodrigues de Araújo, Ivandro de França da Silva, Wagner Magno Catão Barbosa, Maria Gabriela Souza Maioli

Volume: 28 - Issue: 4

Resumo. The oiticica (Licania rigida Benth) is a perennial tree species, oilseed, which has great importance in the semiarid region of Northeastern Brazil by preserving the river margins and the temporary stream. Due to the lack of information regarding the desiccation of oiticica seeds, the study aimed to evaluate the physiological quality of its seeds submitted to different drying periods. The experimental design was completely randomized and the data were submitted to analysis of variance and polynomial regression. The treatments were evaluated by determining the moisture content, seedling emergence, vigor tests (first count, emergency speed index, fresh and dry weight of shoots and roots), and grown analysis (number of leaves, seedling height and stem diameter). Oiticica seeds behave as orthodox, with increase on the emergency when its moisture content is reduced; the critical moisture content below which there is loss of viability is around 6%.

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POTENCIAL ENERGÉTICO DE COMBUSTÍVEIS FLORESTAIS EM CULTIVOS DE Pinus elliottii NO SUL DO BRASIL - (2018)

Aires Afonso Mbanze, Dimas Agostinho da Silva, Alexandre França Tetto, José Fernando Pereira, Antonio Carlos Batista

Volume: 28 - Issue: 4

Resumo. In order to determine the potential energy of forest fuels in Pinus elliottii stands, we investigated the best season to collect fuel material considering fuel availability, moisture content, Higher Calorific Value (HCV) and immediate chemical composition, from the plots established and monitored during one year at Rio Negro Research station, Paraná state, Brazil. The year’s seasons (winter, summer, spring and autumn) were considered as experimental blocks while the diameter of the materials (AA, AB and AC) as treatments. These treatments were pre-defined in the following diameter classes: AA, in the upper layer; AB, in the intermediate layer; AC, in the lower layer, all materials up to 0,7 cm; and B, with material of 0.71 to 2.5 cm. The fuel material of all year’s seasons was collected in sub plots of 900 cm2, weighted in the field and taken to the laboratory of the Federal University of Paraná (UFPR) to carry out the rest of analyzes including: moisture on the dry basis, fuel availability, Higher Calorific Value (HCV) and immediate chemical composition. Analyses of variance (ANOVA) and Tukey test were performed to compare the differences between seasons and material classes. Together with low moisture content and greater fuel availability, the mean test showed that, for all material classes, the winter was the best season to collect forest fuel material of Pinus elliottii stands. The results also showed that, for immediate composition and HCV, the mean class AA and B were statistically superior than the other classes. The fuel loading had a considerable density of energetic (12,275.42.105 kcal. ha-1) for bioenergy conversion and utilization.

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PRODUCTIVIDAD DE UN HARVESTER EN RALEOS DE PLANTACIONES DE PINOS EN EL NORESTE ARGENTINO - (2018)

Eduardo Hildt, Patricio Miguel Mac Donagh, Francisco Ferrando Somma, Diego Alegranza, Daniel Durán

Volume: 28 - Issue: 4

Resumo. Se analizó la productividad de segundos y terceros raleos en plantaciones de Pinus taeda y Pinus elliottii var. elliottii x Pinus caribaea var. hondurensis realizados con harvesters de ruedas en el Noreste Argentino. Los árboles cosechados en los segundos raleos presentaron un volumen medio de 0,43 m3 para Pinus taeda de 12 años y 0,36 m3 para pino hibrido de 10 años, mientras que en los terceros raleos este valor fue de 0,71 m3 para Pinus taeda de 13 años y 0,75 m3 para pino hibrido de 15 años respectivamente. Se desarrollaron modelos de tiempos parciales para cada una de las actividades que componen el ciclo operacional y se determinó la influencia del tipo de raleo, especie cosechada, número de productos elaborados, volumen de los árboles y forma de volteo, sobre el tiempo insumido por cada actividad. Los modelos ajustados fueron integrados en un modelo de productividad efectiva consiguiéndose un coeficiente de determinación ajustado R2 Aj de 0,61. El volumen de los árboles resultó significativo para explicar la duración de todas las actividades evaluadas, siendo especialmente determinante en el volteo de los árboles, su desrame y trozado. El tipo de raleo afectó al tiempo de ubicación, mientras que la especie afectó al tiempo de desrame y trozado. La elaboración de hasta tres productos diferentes requirió un mayor tiempo destinado al desrame y trozado. Ocurrió un aumento de la cantidad de productos cuando se realizaron terceros raleos sobre pino hibrido, respecto Pinus taeda.

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RELAÇÕES BIOMÉTRICAS E AMBIENTAIS NO INCREMENTO DIAMÉTRICO DE Araucaria angustifolia NO PLANALTO SERRANO CATARINENSE - (2018)

Pollyni Ricken, André Felipe Hess, Geedre Adriano Borsoi

Volume: 28 - Issue: 4

Resumo. This study analyzes the relation between biometric, environmental and morphometric variables and the average annual increase in the diameter of a native forest of Araucaria angustifolia in Lages, SC state. To do so, we used dendrochronological data obtained from 121 dominant and competitor trees. The trees were separated into three diametrical classes, ranging from 10 cm to 29.9 cm (C1), 30 to 49.9 cm (C2) and above 50 cm of DBH (C3). The database was formed by a matrix with 121 trees and 23 environmental, dendrometric and morphometric variables, which included flow direction, flow accumulation, solar radiation, face of insolation, slope, altitude, average diameter increment, diameter at breast height, height, distance (dominant/competitive), canopy rays in the north, south, east and west, basal area, age, average ray of canopy, canopy diameter, canopy area, average diameter increment by geographic direction. These variables were obtained using the algorithms from the Digital Elevation Model of the area. The relations were interpreted based on the results of multivariate analysis, using Cluster analysis, factor analysis and principal component analysis. The trees had diameters ranging from 10 and 87.6 cm and heights between 5.3 and 21 m, with average annual increment in diameter of 0.708 cm, with an average of 40 in retrospective analysis. Together with the use of these techniques, we were able to distinguish two groups and six different factors that explain 81.5% of the variance, being formed by morphometric and biometric characteristics of the increment and the relationships with environmental variables. The techniques of multivariate analysis can be applied to aid the decision-making in forest management, because they proved the correlation between the average increment in diameter (essential to compose the forest cutting cycle) and its relation to environmental factors, index form, space and dimension of individuals.

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SEGURANÇA AMBIENTAL NA ESTAÇÃO ECOLÓGICA DE ÁGUAS EMENDADAS NO DISTRITO FEDERAL - (2018)

Alexandre Nascimento de Almeida, Bruno Gonçalves de Andrade, Philipe Ricardo Casemiro Soares, Humberto Angelo

Volume: 28 - Issue: 4

Resumo. Conservation Units (CUs) have ecological and economic importance and, in Brazil, are divided into two categories: full protection and sustainable use. Within the CUs of full protection are the Ecological Stations (ECST), typology where public visitation is prohibited and that demands an effective security apparatus so that its ecological function is achieved. Thus, the objective of the study was to analyze the security of ‘Águas Emendadas’ Ecological Station (AEECST). To do so, from the responses to the questionnaire applied in person to the Environmental Military Police (EMP) of AEECST, it was used the regression analysis to identify the determinants that affect the working conditions of the security in the unit. In addition, it was evaluated the profile of EMP from AEECST by descriptive statistics and investigated working conditions in the unit by correspondence analysis. The determinants for effective security of ESECAE were the contingent size followed by the appreciation of the police by the administration and, finally, the amount of equipment needed to carry out the work of the EMP in the unit. The results showed that the AEECST battalion is experienced and in sufficient quantity, excepting the lack of some basic equipment, in general, working conditions in the unit are satisfactory and the safety is effective, ensuring the limitations of use in the area provided by law.

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VANTAGEM COMPARATIVA E MATRIZ DE COMPETITIVIDADE DO MATE BRASILEIRO E ARGENTINO, NO PERÍODO DE 1997-2011 - (2018)

Elisangela Lobo Schirigatti, João Carlos Garzel Leodoro da Silva, Alexandre Nascimento de Almeida, Anadalvo Juazeiro dos Santos, Neusa de Almeida Rucker

Volume: 28 - Issue: 4

Resumo. This article aims to analyze the performance of exports from Brazil and Argentina in the international mate market. The analysis method used refers to the Revealed Comparative Advantage Index (IVCR) of the Brazilian and Argentine mate, during the period from 1997-2011. At the beginning, it was verified the existence of structural breaks of the time series, then, were investigated the rate of market growth and the Symmetric Revealed Comparative Advantage Index (IVCRS) that were used to identify the mate position of each country in the competitiveness matrix. The results obtained in the whole period showed that both the Brazilian and Argentine mate presented products that have comparative advantage (+) in markets with increasing demand (+).

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VARIAÇÃO ESPAÇO-TEMPORAL DA PAR REFLETIDA PELO SOLO E TRANSMITIDA PELO DOSSEL EM FLORESTA INUNDÁVEL NO PANTANAL MATO-GROSSENSE - (2018)

Jonathan Willian Zangeski Novais, Luciana Sanches, Vanessa Rakel de Moraes Dias, Nadja Gomes Machado, Ludymilla Barboza da Silva, Aryadne Marcia Aquino

Volume: 28 - Issue: 4

Resumo. Ground cover and the vegetation type influence radiative flux through reflectance off the soil beneath the canopy and by transmittance from the canopy. Here, we analyze spatial and temporal variation in reflected photosynthetically active radiation (PAR), from soil in a seasonally flooded forest dominated by Vochysia divergens Pohl in a wetland area of Mato-Grosso State, Brazil. The study area was divided into 5 transects with 11 sampling points, totaling 55 measured points and samples were taken between December 2011 and November 2012. The spatial distribution of reflected PAR was assessed by applying the spherical model to semivariograms. We found a negative correlation between leaf area index and canopy transmittance, PAR below the canopy and PAR reflected by soil, and a positive correlation between PAR below the canopy and PAR reflected by soil. Our results indicate the spatial dependence of reflected PAR during the 9 months of the study. The most common range between the semivariograms was 100 m in December/2011, January/2011 and November/2012, and the greatest range was in June/2012. These variations in reflected PAR are likely caused by differences in topographical elevation, moisture buildup and vegetation differences which have the capacity to alter soil color and/or cover, thereby altering light reflection.

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A INFLUÊNCIA DAS DIFERENTES TIPOLOGIAS DE FLORESTA URBANA NO MICROCLIMA DO ENTORNO IMEDIATO - (2018)

Angeline Martini, Daniela Biondi, Antonio Carlos Batista

Volume: 28 - Issue: 3

Resumo. The urban forest generates a microclimate more pleasant for the human being, in its interior as in the near external areas. Thus, the main goal of this research was to analyze the influence that the different typologies of urban forest exert in their immediate surrounding, highlighting quantitatively the differences between the internal and external microclimate to these areas. For this, areas of different types of urban forest were selected in the city of Curitiba-PR: Remaining Forest, Old Green Area, Modern Green Area, Street Trees and Isolated Tree. The influence in the immediate surrounding was analyzed with the mobile transect method, traveling 500 m away from a street adjacent to the selected area, with data collection every 50 m. The results indicate statistical differences between the internal and external microclimate to the typologies of urban forest. During the transect, the temperature was on average 2.3 ° C higher than in the interior of the urban forest typologies, the relative humidity was lower in 4.6 units and the wind velocity 0.2 m / s higher. The greatest difference in temperature and relative humidity between the internal and external environment was found in the Remaining Forest and the smallest in the Street Trees. It is concluded that the different typologies of urban forest exert a significant influence on the immediate surrounding microclimate.

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ACTIVATED CARBON FROM BAMBOO (Bambusa vulgaris) FOR METHYLENE BLUE REMOVAL: PREDICTION TO THE ENVIRONMENT APPLICATIONS - (2018)

Gregório Mateus Santana, Roberto Carlos Costa Lelis, Juarez Benigno Paes, Rayssa de Medeiros Morais, Cláudio Rocha Lopes, Carlos Roberto de Lima

Volume: 28 - Issue: 3

Resumo. Activated carbon (AC) is an essential product for the removal of environmental contaminants, but the high production costs limit its use. In this work, AC was produced from bamboo through simultaneous direct physical-chemical activation (by using phosphoric acid and water steam), at 500 ºC for 1 hour, to evaluate its adsorption effectiveness for methylene blue dye (MB). Adsorption kinetic and equilibrium studies at batch system were realized at room temperature (to evaluate the adsorption influence of the MB dye over the produced AC) and the Langmuir and Freundlich isotherms systems were selected for understanding the adsorption process. The produced AC showed a relatively high value of surface area equal to 1354.42 m².g-1. The required contact time for the MB to reach equilibrium was 12 hours. The adsorption performance was better delineated by the Langmuir isotherm, which maximum adsorption capacity was of 374.75 mg.g-1. In addition, the RL dimensionless factor reveled the favorable nature of the adsorption process in the used conditions. The results obtained in this study recommend the use of the produced AC from bamboo in the treatment of the water contaminated by the MB dye, foremost in higher concentrations than limits admitted by the legislation. Finally, complementary researches must be conducted to improve, even more, the quality of the produced material.

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ANÁLISE DO PERFIL DOS INCÊNDIOS FLORESTAIS NO PARQUE ESTADUAL DA SERRA DO BRIGADEIRO E ENTORNO (MG) - (2018)

Fillipe Tamiozzo Pereira Torres, Carlos Moreira Miquelito Eleto Torres, Gumercindo Souza Lima, Sebastião Venâncio Martins, Ana Eurica de Oliveira Mendes, Michele Tidisco Padovani, Rafael Gomes Siqueira, Gilberto Fialho Moreira, Sebastião Renato Valverde

Volume: 28 - Issue: 3

Resumo. Fire is one of the main problems of the Atlantic Rainforest biome, even in protected areas such as Protected Areas (PAs or UC, in Portuguese). Thus, the aim of this study was to know the profile of forest fires in the Serra do Brigadeiro State Park (PESB-MG) and surroundings, as well as their responses in environmental variations. For this, we analyzed the information of Fire Incident Report (FIR or ROI, in Portuguese) and their interrelations with the environmental PESB systems through the analysis of spatial plans (land use and land cover and topography) and temporal (climatological elements). According to the results, only 38% of the records showed the causes of fires, of these, 77% were identified as anthropic. Analyzing the burned area, there was the highest number of occurrences within the class III (4.1 - 40.0 ha). The herbaceous vegetation, because of their favorable characteristics, was hardest hit. The relief also influenced the events, slope, aspect and height participated significantly in the fire regime in the Park. The anthropic activity showed its influence to increase the size of the area burned in the vicinity of access routes. The climate controlled the temporal arrangement of events, where periods of lower Relative humidity of air, made the months of August and September as belonging to the normal fire season and accumulated rainfall determined the most problematic years. The results presented here provide information to support the making of more safe and reliable decisions in the prevention of forest fire occurrences in PESB and surroundings, as they contribute to a better understanding of the factors that control the fire occurrences in the region.

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AVALIAÇÃO DO DESGALHADOR FLORESTAL DE DISCOS EM FUNÇÃO DO TEMPO DE ESTOCAGEM DA MADEIRA EM CAMPO - (2018)

Rodrigo Petrongari Tonin, Ricardo Hideaki Miyajima, José Raimundo de Souza Passos, Paulo Torres Fenner

Volume: 28 - Issue: 3

Resumo. With the innovations of mechanized harvesting in Brazil, become necessary studies to obtain real data on the new machines that are emerging in the market. The study aimed to the technical evaluation and cost a forest delimber on trees with different times storage in the field, and verify possible correlations among wood moisture, productivity and cost of production. For the technical analysis was conducted a study of time and motion by timing method of continuous time and for the cost analysis, we calculated operating costs through the method proposed by ASABE. Approximately 40 days in the field trees reached the equilibrium moisture content, the moisture has demonstrated no correlation of content with the performance of the machine, which was on average 643.34 m3/h, and not with the cost of production, and, the operating cost of R$ 180.04 / hour, and the production cost average R$ 0.28 / m3.

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AVALIAÇÃO DO EFEITO DAS VARIÁVEIS DE PROCESSO NO BRANQUEAMENTO DE POLPA CELULÓSICA COM PERÓXIDO DE HIDROGÊNIO - (2018)

Camila Juliane Marcondes, Gustavo Ventorim, Rafael dos Santos, Felipo Augusto Pereira

Volume: 28 - Issue: 3

Resumo. The bleached pulp market has been working to provide brightness levels at values of 92% ISO respecting, however, environmental standards and seeking for less aggressive processes. Then, the additional chlorine dioxide that would be necessary to lift brightness ​​has been replaced by hydrogen peroxide. The present study aimed to evaluate the influence of hydrogen peroxide charge, pressure and temperature variation in the bleaching sequence D0(E+P)D1(P+O). It was used industrial kraft pulp, from hybrid of Eucalyptus urophylla X Eucalyptus grandis, oxygen-delignified, whose initial characteristics were: brightness 61.8% ISO, viscosity 36.9 cP and kappa number 8.9. The last stage (P+O) was performed varying the hydrogen peroxide charge (3 kg/t and 6 kg/t), temperature (95°C and 105°C) and pressure (0 atm and 5 atm). To evaluate the effect of such variations over cellulosic pulp, viscosity, brightness and brightness reversion tests were carried out according to TAPPI standards. In general, increase of hydrogen peroxide charge (from 3 kg/t to 6 kg/t) caused a small increasing on brightness values and a small viscosity decreasing on the cellulosic pulp. The increase of 10°C in temperature had a positive effect on brightness parameter, increasing the respective values, on the other hand, for the viscosity analysis the achieved values showed a reduction tendency. For the variation of oxygen pressure it was also observed brightness increasing and viscosity decreasing.

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CARACTERÍSTICAS MORFOFISIOLÓGICAS FOLIARES E ESTADO NUTRICIONAL DE SEIS ESPÉCIES LENHOSAS EM FUNÇÃO DA DISPONIBILIDADE DE ÁGUA NO SOLO - (2018)

David de Holanda Campelo, Claudivan Feitosa de Lacerda, João Alencar de Sousa, Antônio Marcos Esmeraldo Bezerra, José Dionis Matos Araújo, Antônia Leila Rocha Neves, Carlos Henrique Carvalho Sousa

Volume: 28 - Issue: 3

Resumo. The reduction in water availability effects plant physiology and morphology and accounts for changes in metabolism with implications for the development of tree species. The objective of this study was to evaluate the influence of water stress on morphophysiological leaf characteristics and nutritional status of adult plant of gonçalo-alves (Astronium fraxinifolium), guanandi (Calophyllum brasiliense Cambess.), ipê-amarelo (Handroanthus serratifolius (Vahl.), ipê-rosa (Handroanthus impetiginosa (Mart.) Matos.), marupá (Simarouba amara Aubl.) and mogno (Swietenia macrophylla King.) cultivated under rainfed and irrigated conditions, in the irrigation perimeter of Baixo Acaraú, Ceará. The experimental design was a repeated measures, a scheme of sub-divided plots (6 x 2 x 2), the main plot consists of six species, the sub-plot of two water availability (irrigated and rainfed) and the sub-subplots were the evaluation time. The following evaluations were performed during the dry and rainy seasons: foliar concentrations of N, P, K and Na, specific leaf area (AFE), leaf succulence (GS), and relative index of chlorophyll (IRC). The results showed that ipê-amarelo was the most sensitive species in terms of variation of N, P and K concentrations in leaves in response to soil water availability. Regarding AFE, ipê-amarelo, ipê-rosa and mogno were more sensitive to extreme water deficit conditions. The water restriction in the soil causes the decrease of the leaf succulence in the gonçalo alves and mogno. The chlorophyll is directly affected by drought and is related to the higher GS and the lower AFE. As for A/N and A/P, gonçalo-alves was more efficient species, not affected by soil water availability conditions.

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CARACTERIZAÇÃO MORFOMÉTRICA, GERMINAÇÃO E CONSERVAÇÃO DE SEMENTES DE Triplaris brasiliana CHAM. (POLYGONACEAE) - (2018)

João Correia de Araújo, Jonhclécio Duarte Teixeira, Maria Inajal Rodrigues da Silva das Neves, Luan Danilo Ferreira de Andrade Melo, Vilma Marques Ferreira

Volume: 28 - Issue: 3

Resumo. The objective of this study was to characterize morphometrically seeds, evaluate the treatments of scarification, and germination temperatures and the potential seed storage Triplaris Brasiliana Cham., a pioneer species, with great potential for recovery of degraded areas, permanent preservation, riparian areas and land. For the morphometric characterization, it was determined the length and thickness, mass of 1000 seeds, color, shape and hilum and micropyle location, such embryos, the location and type of germination. The germination test was evaluated from seeds with and without scarification at different temperatures. The storage was tested in glass and paper packaging and in refrigerator, dry chamber and ambient conditions. The embryo is axial, and the embryonic axis in the central part of the seed of the lower half, the germination is epigeal and the seedlings are fanerocotylar. Sowing the seeds scarified on paper subjected to 30 °C were more favorable for germination and development of Triplaris brasiliana seedlings, and seeds sensitive to dehydration (intermediate), while preserving physiological quality for longer when stored in the refrigerator and camera in the packages used.

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Cedrela odorata L. TEM POTENCIAL PARA SER UTILIZADA NA SILVICULTURA PÓS-COLHEITA NA AMAZÔNIA BRASILEIRA? - (2018)

Sabrina Benmuyal Vieira, João Olegário Pereira de Carvalho, Jaqueline Macedo Gomes, Joice Carolina Fernandes da Silva, Ademir Roberto Ruschel

Volume: 28 - Issue: 3

Resumo. This study deals with the performance of Cedrela odorata L. (cedar) seedlings planted in gaps created by reduced impact logging, in the municipality of Paragominas, state of Pará, Brazil. The survival and growth rates of seedlings were evaluated in order to find out the possibility of planting them in gaps caused by the reduced impact logging in the Brazilian Amazonia. Four hundred gaps were chosen in 200 ha and they were divided in three size classes: small (200-400 m2), medium (401-600 m2) and large gaps (> 600 m2). Four hundred and seventy seedlings of cedar were planted in 236 gaps in 2005, when the first assessment was carried out. Other assessments occurred in 2006, 2008 and 2010. Five years after planting the survival of seedlings was circa 81,8% and the mean growth rate was 70,0 cm year-1 in height and 0.23 cm year-1 in diameter. Therefore, we can suggest Cedrela odorata L. for enrichment planting in forests after logging, considering its good performance in gaps. Continuous monitoring is needed.

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COMPETIÇÃO VERSUS CRESCIMENTO DE ÁRVORES EM FLORESTA OMBRÓFILA DENSA NO ESTADO DO AMAPÁ - BRASIL - (2018)

Silvane Vatraz, José Natalino Macedo Silva, Denis Alder

Volume: 28 - Issue: 3

Resumo. The objective of this study is to make, comparatively, of different distance independent competition indices (IID) in three dimensions of plots, and to identify those that more correlate with diametric increment (IPA DAP), in order to determine which best explains inter-tree competition in the arboreal stratum in a dense ombrophylous forest. This study was conducted with the Project Good Management data (Embrapa / CIFOR / ITTO) - Sustainable management of production forests on a commercial scale in the Brazilian Amazon, developed by Embrapa Amazônia Oriental in the area of Jari Florestal SA, in the municipality of Vitória do Jari, State of Amapá. Three permanent plots were used of one hectare each (100 x 100 m), on which were measured all trees with DBH ≥ 20 cm. The following IIDs were compared: G (basal area / ha), BAL (Basal Area of Larger Trees), Glover and Hool and Stage. The competition indices were evaluated by analysis of linear correlation coefficients between each index and the PAI DBH (cm-1) variable. The significance of the correlation coefficients was evaluated by p value (α = 0.05). All variations of indexes tested resulted in correlations of up to 20%, considered to be very weak. This indicates that IIDs can represent only partially the competition in tropical natural forests. However, among the indexes, the BAL index is the IID that presented the highest correlation with the PAI DBH (r = -0.212 and p = 0.000) in plots of 50 mx 50 m and, therefore, even if it has a low correlation, it is the indicated for competition studies on diametric growth in natural tropical forests. A spatial relationship of the IIDs was detected, where the correlation decreases with the increase of the plot size. Additional research is recommended to evaluate the effects of competition on tree growth, as well to increase understanding of intraspecific and interspecific competition in order to improve knowledge of the competition dynamics in tropical forests.

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CRESCIMENTO E TOLERÂNCIA DE MUDAS DE Enterolobium contortisiliquum Vell. CULTIVADAS EM SOLO CONTAMINADO COM ZINCO - (2018)

Rodrigo Ferreira da Silva, Clovis Orlando Da Ros, Zaida Ines Antoniolli, André Luis Grolli, Douglas Leandro Scheid, Gilvan Moises Bertollo, Evandro Luis Missio

Volume: 28 - Issue: 3

Resumo. Zinc is an essential element to plants, but when present in high concentrations in the soil can become toxic to the plant metabolism. The study aimed to determine the growth and tolerance of Enterolobium contortisiliquum Vell. seedlings cultived in soil contaminated with zinc. The experiment was conducted in a greenhouse in soil with 81% clay, in a completely randomized design with seven treatments, doses of zinc (0, 100, 200, 300, 400, 500 and 600 mg kg-1) eight repetitions. We evaluated the plant height, stem diameter, shoot dry mass, root dry mass, length of the main root, specific surface area, Zn content in shoots and roots, the impact coefficient of relative zinc content, translocation and tolerance. The coefficient of impact of the relative zinc content indicated a trend of lower translocation of Zn to the aerial part of the molt up to the dose of 300 mg of Zn kg-1 of soil. The results showed that doses close to 200 mg Zinc kg-1 clay soil stimulate plant height, stem diameter, stem and root dry mass of seedlings and timbaúva. Timbaúva presents high tolerance to zinc and because it is a native tree adapted to Brazilian environmental conditions it can be indicated for revegetation of contaminated areas with the application of up to 600 mg of zinc kg-1 of clay soil.

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DAMAGE TO REMAINING TREES BY FOUR SYSTEMS OF MECHANIZED HARVEST IN COMMERCIAL THINNING OF Pinus radiata - (2018)

Eduardo Acuña, Eugenio Sanfuentes, Jorge Cancino, Pablo Mena

Volume: 28 - Issue: 3

Resumo. The effect of four harvesting systems for thinning tasks (harvester-forwarder, chainsaw-skidder, chainsaw-three-wheeled loader and chainsaw-yarder) was evaluated on percentage of damaged trees and damage surface. Additionally, the effect of the logging system and the season of the operation (winter and summer) on the incidence of damage and surface of the injuries, and their relationship with tree diameter, was also analyzed. Of the four logging systems studied, those carried out with chainsaw-yarder and harvester-forwarder originated the greater incidence of damage with 34.5% and 32.2%, respectively, also producing the greatest injuries with 349.7 and 427.2 cm2, respectively, by individual tree. The season in which the operations were conducted is a factor that significantly affected on the increase of the number of trees with some sort of damage, with an average incidence of 27.1% in winter and 10.1% in summer. In addition, tree extraction with forwarder and yarder has a high potential for residual stand damage, and the stand structure was not affected by mechanized thinning, because there were damages in all sizes of remaining trees.

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