RCAAP Repository

The objective of this study was to verify the efficiency of nondestructive evaluation of wood panels mechanical properties by stress wave timer method in medium density particle board (MDP) from pine. Were evaluated industrial MDP panels from eucalypts (5) and pine (5), both from two national companies, and five panels from sugarcane bagasse imported from China. Stress wave timer method was used for nondestructive evaluation. The modulus of elasticity (MOEd) obtained by stress wave timer method was confronted with MOE and flexural strength (MOR) to bending tests from conventional assays. Measures in length and width directions were performed in each panel. Nondestructive method was effective only for sugar cane bagasse panels, so it can be used to predict MOE and MOR for this type of panel.

Mechanical properties of charcoal are indicators of quality and they influence in steelmaking process. In general, assessment tests (falling and tumbling) present variable results compromising their reliability. So, it is important to develop methodologies that produce comparable results. This study aimed to analyze the influence of sample length to determine stiffness and strength of wood and charcoal. Samples were produced from Eucalyptus urophylla clones, presenting cross section 25 mm x 25 mm and lengths of 50 mm, 75 mm, 100 mm and 125 mm. Ten samples of each length were selected for testing wood, and another ten for testing charcoal. The modulus of elasticity and compressive strength were determined in compression test parallel to the fibers. There was a significant effect of sample length on stiffness and strength of wood and charcoal. The best results were found for samples of 25 mm x 25 mm x 75 mm. Only the dimension 25 mm x 25 mm x 50 mm proved inadequate, presenting lower results than those reported in literature.

The main objective of this study was to evaluate wood thermal degradation and the release of condensable and non-condensable gases during charcoal production from Eucalyptus spp. with approximately seven years old. The wood samples were from a clonal test of a forest company from Divinésia, Minas Gerais State, Brazil. Thermogravimetric analysis (TGA/DTA) and carbonizations in muffle were carried out to determine the wood thermal performance and emission factor of non-condensable and condensable gases. Wood thermal degradation presented opposite performance of carbon dioxide (CO2), carbon monoxide (CO), methane (CH4), hydrogen (H2) and condensable gases, presenting a minimum of degradation point and maximum emission at temperatures of 300 °C and 350 °C, respectively. During carbonization process it was observed three distinct behaviors: drying the wood in temperatures near 200 °C; maximum peak emission of CO2, CO and pyrolignous in temperature range corresponding to 300 °C and 450 °C; and CH4 and H2 gases increases according to temperature increases from 300 °C.

Indole-3-butyric acid (IBA) is a plant growth regulator widely used to induce rooting of cuttings. The objective of this work was to evaluate the effect of different concentrations of IBA and of two cuttings types in vegetative propagation of Senna alata (Linnaeus) Roxburgh. The experiment was established in a completely randomized design with four repetitions, in factorial 4 x 2, using four concentrations of AIB: T1 – 0 mg L-1 (control); T2 – 250 mg L-1; T3 – 500 mg L-1 and T4 – 1,000 mg L-1 and two cuttings types (E1 – herbaceous and E2 – semi-hardwood). Each experimental unit consisted of 12 cuttings. The studied growth regulator concentrations did not influence seedlings root and aerial systems development and, therefore, the survival in shade house. In greenhouse, herbaceous cuttings lost less remaining leaves after leaf area reduction (27.88%) and, consequently, had higher survival (99.44%) when were kept in shade house. Herbaceous cuttings can be recommended for vegetative propagation of S. alata.

Reliable biomass data are very important in the evaluation of ecosystems, and help in understanding the contribution of forests in climate change. Variables that describe the size of the tree, like diameter and height are directly associated with biomass, which allows the use of regression models to estimate this element. Therefore, this study aimed to estimate by regression models, the biomass of different compartments of natural regeneration of trees of a Pinus taeda L. stand. The data were obtained through direct destructive method, using 100 randomly selected trees in the understory of a stand of Pinus taeda. We analyzed three arithmetical models, three logarithmic and two models developed by Stepwise process. Logarithmic equations developed by Stepwise procedure showed the best estimates of total and stems biomass. However, for needles and twigs compartments the best adjust was observed with Husch model and for root biomass Berkhout model proved to be the most suitable.

Torrefaction also known as pre-carbonization is heat treatment at low temperatures (200 ºC to 300 °C), applied to lignocellulosic materials with the aim of improving their energetic properties. We developed this study to evaluate the effect of torrefaction temperature on properties of eucalyptus chips. Using a furnace, the eucalyptus chips underwent four heat treatments at temperatures of 150 ºC, 200 ºC, 250 ºC and 300 °C, for ten min. Physical and chemical analyzes of torrefied and in natura chips were carried out. The results were submitted to analysis of variance and when established significant differences, applied Tukey test at 95% significance. Increasing roasting temperature showed higher lignin content and fixed carbon, less equilibrium moisture content, higher calorific upper, lower content of volatiles and lower mass yield. It is recommended roasting at 250 °C temperature, since chips torrefied under this condition presented better results, with energy density of 4,004 MJ m-3.

The giant conifer aphid, Cinara atlantica, originated from North America, was introduced in Brazil in the 1990’s and became widely distributed on commercial areas of Pinus. This study was conducted in order to correlate morphometric parameters of mono and multiclonal C. atlantica lineage with its reproductive performance on plant progenies and commercial seedlings. The number of nymphs produced by female by day were registered. After death, measurements of morphological characters were carried out using the program Axion Vision 4.5. Antenna, hind femur and tibia lengths showed the highest correlation with aphids body length, representing 98% of total variation. Based on these variables a new variable was defined as ‘insect size’, which was used to compare treatments. Multiclonal insects had the highest values for most morphometric parameters and largest progeny production. The biggest insects and highest nymph production were observed on commercial seedlings of both nurseries, suggesting that these pine progenies may show some resistance against C. atlantica attack what make them good candidates for integrated pest management programs.

Geographic information system (GIS) applied to forest analysis permit the recognition and analysis of spatial patterns of species in two and three dimensional. The aim of this study to demonstrate the efficiency of cartesian and spatial coordinates method (MCCE), method of correcting UTM coordinates of trees location in accordance with the location of field or Cartesian (X ,Y), combined with natural neighbor index (ANND) in recognition and analysis of spatial distribution patterns of four commercial timber species in forest management in Caracaraí, Roraima State, Brazil. Simulations were performed on 9 ha, divided into 100 plots of 100 m2 each. Collected data were DBH > 10 cm, commercial and total heights, cartesian coordinates (X,Y) and spatial coordinates (UTM). Random spatial patterns were observed in Eschweilera bracteosa and Manilkara huberi. The dispersed and rare spatial patterns were observed in Dinizia excelsa and Cedrelinga cateniformis. MCCE proved to be an efficient method in the recognition and analysis of spatial patterns of native species from Amazon rain forest, as forest planning becomes easier by 2D and 3D simulations.

The object of this work was to characterize sawn wood of Eucalyptus clones with 7 to 13 years old planted on Entre Rios and Esplanada regions, Bahia State. For comparison and reference Eucalyptus cloeziana samples with 22 years old were used, as this species present great saw timber potential. Samples were taken along trees trunks on two vertical and three radial positions. Differences were observed among clones and radial position for end splitting of dry lumber, bowing and bending indexes, and number of knots although there was no evidence of difference due to log position along the trunk. All materials presented high incidence of knots. End splitting of the dry lumber and bending indexes and number of knots decreased from pith to bark, while bowing tended to increase.

Schizolobium parahyba var. amazonicum (paricá) is a native tree species, widely used in reforestation. However, the damages caused by insects to the species reduce the photosynthetically active area, interfering with final growth. Therefore, the objective of this work was to evaluate the recoverability of paricá in early ages after a simulated defoliation. The experiment was designed in randomized blocks divided in four experiments with four replications, separated into two distinct periods (30 and 60 days after emergence) and the percentage of leaves and folioles. After 30 and 60 days of plants emergence, defoliation was carried out. After 30 days in both phases plants height, stem diameter and leaf recovery were evaluated. Data of all defoliation percentages were submitted to variance and regression analyses. Under artificial defoliation, paricá had low reduction in growth and good capacity for damage recovery and it was therefore considered tolerant to different damage percentages tested.

The production of forest seedlings in quantity and quality is one of the most important stages for more uniform and productive forest stands establishment. A higher survival and development of seedlings after planting are dependent, among other factors, of their good nutritional status. This study aimed to evaluate the potential use of two bio-fertilizers based on amino acids as initial growth promoters of Eucalyptus dunnii Maiden seedlings, known respectively as “BIO 1” and “BIO 2” .The experiment was conducted in a commercial nursery in Imbituva, Parana State, Brazil. It was used a completely randomized design, with three treatments and four replications, with 50 seedlings per replication. The variables evaluated were: plant height, stem diameter, fresh matter weight of shoot and of roots, dry matter weight of shoot and roots, roots length and Dickson quality index (DQI). There were positive responses to bio-fertilizers application for all studied variables, especially when applied BIO 2.

The objective of this study was to evaluate the growth response of Mimosa bimucronata (DC) O. Kuntze seedlings in nursery conditions to inoculation with rhizobium strains previously selected using different substrates. An experimental design of randomized blocks with split plots was used, testing three substrates (pure organic-containing clay, sand and manure in 1: 1: 1 v: v: v ratio; organomineral mixed with 30% straw and sand with vermiculite in 1: 1 v: v) and four N sources (inoculation with strains BR 3461 and BR 3470, control with N fertilization and control without fertilization), totalizing 12 treatments. Height and stem diameter were evaluate after 90 days and shoot, root and nodules dry mass were evaluate after 120 days. Organomineral substrates provided better seedling growth. However, only organic-substrate with straw and sand with vermiculite showed positive responses of plants inoculated with BR3470 strain. The performance of the inoculated seedlings was not higher than that of seedlings fertilized with N. The rate of N applied stimulated nodulation rather than inhibit it.

After Landsat 5 activities were discontinued, sensors on board ResourceSat-1 satellite have been pointed as an option for Landsat series. The aim of this study is to estimate timber volume from a slash pine (Pinus elliottii Engelm.) stand using images from both LISS-III/ResourceSat-1 and TM/Landsat 5 sensors, cross comparing their performances. Reflectance values from the four spectral bands considered equivalent for both sensors were compared regarding sensitivity to changes in timber volume. Trends were similar, with direct relationship in the near-infrared bands and inverse relationships in the visible and mid-infrared bands. Significant differences were only found in the equivalent band of green. Multiple linear regressions were used to select spectral bands that would better explain variations in timber volume. The best fit equations for each sensor were inverted to generate maps of timber volume, estimates which were compared at pixel and stand level. None of the scales showed significant differences between estimates generated from the two sensors. We concluded that LISS-III and TM have generally very similar performance for monitoring timber volume, and LISS-III could therefore be potentially used as a complement or substitute to Landsat series.

Given the strong generation of solid organic waste and wastewater, the use of these materials as a primary source of nutrients is an important practice in environmental management, especially in the production of seedlings with emphasis on degraded areas. The objective of this study was to evaluate growth and nutrient balance of “tamboril” (Enterolobium contortsiliquum (Vell.) Morong) seedlings grown on substrates with different formulations proportions of organic matter irrigated with wastewater. It was tested five ratios of organic composts and soil: 0:100; 20:80; 40:60; 60:40 and 80:20 v/v. Two procedences of irrigation water was tested: water supply and wastewater from swine farming, arranged in a completely randomized design in a factorial scheme 5 x 2, with four replications. At 90 days, we evaluate seedlings morphological variables, the integrate diagnosis recommendation index and the nutrient balance index. The organic residue contributes to seedlings growth and nutritional balance. The proportion 80:20 proved to be the most suitable for “tamboril” seedlings production. Seedlings presented lower growth and nutritional balance when irrigate with swine farm wastewater.

The objective of this study was to evaluate the effects of two cryoprotectants followed by thawing on the physiological potential of Genipa americana L. seeds. Two experiments testing 12 treatments were conducted, one for each cryoprotectant, both in a factorial scheme of 6 × 2 (cryoprotectant concentrations × thawing methods). We tested 0, 5, 10, 15, 20, and 25% for dimethyl sulfoxide, and 0, 0.25, 0.5, 0.75, 1.0, and 1.25 M for sucrose. The thawing methods were fast (38 °C for 30 min) and slow (25 °C for 4 h). The seeds were immersed in the cryoprotectant solution for 3 h, stored for 120 h, and then thawed. The seeds were then sown in substrate (sand and vermiculite, 1:1). Emergence percentage along with speed index, length, fresh and dry matter mass of seedlings were evaluated. Dimethyl sulfoxide and sucrose can be used as cryoprotectants in G. americana seeds. Thawing should be slow when treating seeds with dimethyl sulfoxide.

Vegetative propagation success of commercial genotypes via cutting techniques is related to several factors, including nutritional status of mother trees and of propagation material. The nutritional status determines the carbohydrate quantities, auxins and other compounds of plant essential metabolism for root initiation and development. Each nutrient has specific functions in plant, acting on plant structure or on plant physiology. Although the importance of mineral nutrition for success of woody plants vegetative propagation and its relation with adventitious rooting is recognized, the role of some mineral nutrients is still unknown. Due to biochemical and physiological complexity of adventitious rooting process, there are few researches to determine de role of nutrients on development of adventitious roots. This review intends to explore de state of the art about the effect of mineral nutrition on adventitious rooting of woody plants.

This study aimed to compare the economic viability of the forestry component from an agri-silvi-pastoral system to tree plantation in a small property in Esperança do Sul municipality, Rio Grande do Sul, State, Brazil. The agri-silvi-pastoral system used only eucalyptus, and the tree plantation was formed using eucalytpus and black wattle. The analysis was carried out using tree component and data were obtained by forest inventory. The indicators selected for economic and financial analysis were: net present value (NPV), equivalent annual value (EAV), internal return rate (IRR), benefit/cost reason (B/C) and average cost of production (ACP). The discount rate used was 7.5% year-1. Both systems were considered economically and financially viable, in 10 or 15 years rotation. However, 15 years rotation presented the biggest financial return. Agri-silvi-pastoral system was considered feasible, maintaining positive results even with higher interest rates. Even though the tree plantation presented greater economic returns, the agrisilvipastoral system showed more environmental benefits.

This study aimed to determine and evaluate the diameter influence on lumber yielding of Qualea sp. The study was carried out in a sawmill in Mato Grosso State, Brazil. We selected randomly sixty logs that were grouped in four classes of fifteen logs each. The evaluated classes were: diameters smaller than 55 cm (class I); between 55 and 65 cm (class II); between 65 and 75 cm (class III) and diameters greater than 75 cm (class IV). Average yield of Qualea sp. was approximately 52%. It was also observed that the diameter class influenced significantly the performance of cambará, with class IV presenting the highest yield. However, there was no significant linear trend relationship between variables. It was observed a parabolic behavior, with higher yield percentages observed for the highest and lowest diameter classes.

The objective of this study was to analyze the ability of an artificial neural network (ANN) to estimate the total height of two tree species in different growing conditions. For comparison purposes, it was also adjusted Campos hypsometric model, applied by stratum as genus, species, rotation, spacing and age classes. The evaluation of artificial neural networks and Campos model was based on the correlation coefficient between the observed and estimated heights, the square root of the mean square percentage error (RMSE) and graphical analysis. The results of this study showed that trees height of different species, in different growing conditions and locations can be estimated using a single neural network with the same efficiency and accuracy usually obtained with regression equations.

Calophyllum brasiliense is a tree species with limited natural reproduction. In vitro germination may be an alternative for obtaining high-quality seedlings. Seeds were maintained in water before surface disinfestation and compared with control seeds (i.e. not immersed), without differences between treatments. HgCl2 used during surface-disinfestation reduced contamination rates of cultures. Fungal contamination was reduced with fungicide added to culture medium (23 to 6.4%), although bacterial contamination increased (24 to 36%). In another experiment, seeds were immersed in plant preservative mixture (PPM™) prior to surface disinfestation. By combining immersion for 48 h and 2 mL L-1 in culture medium, contamination was only 6%. Seeds immersion in GA3 prior to surface disinfestation reduced root formation as concentration increased. Germination rate and GSI were reduced, respectively, from 72% and 0.129 (24 h) to 60% and 0.092 (48 h) according to exposure time to GA3. After 90 days in multiplication medium containing benzylaminopurine, average number of shoots per nodal segment was 3.4. In conclusion, in vitro germination of C. brasiliense seeds is feasible in sucrose-free WPM medium and reaches a high contamination-free rate (up to 93.3%).