EFFECT OF THINNING ON VOLUMES OF BIOMASS AND BARK TANNINS CONTENT OF Mimosa caesalpiniifolia BENTH. TREES

ABSTRACT This research aimed to evaluate the effect of thinning on the wood volumes per hectare on the tannin content in the bark of Mimosa caesalpiniifolia. The planting was subdivided into two plots, one thinned at 12 and 55 months of age (T1), while the other plot was kept intact (T2). The dendrometric variables were measured, and ten trees were felled, five in each plot. Subsequently, wood and bark’s volume, mass, and moisture content were determined. Then, the total solids content (TST), the Stiasny index (I), and the condensed tannin content (TTC) were quantified. Dry wood productivity was statistically different between the two treatments, with values of 26.7 and 22.8 t ha-1 for T1 and T2, respectively. The percentage of dry bark corresponded to 16% of the total biomass for both treatments. The only variable that showed a significant difference was I, with values with and without thinning, 59.83 and 79.31%, respectively. Therefore, it was verified that the way the thinning was used changed the I and how they were conducted, favoring the emission of boles and increasing the frequency in the lower diametric classes instead of favoring the increase in DBH. It is concluded that thinning interferes with the biomass volumes and the Stiasny index of M. caesalpiniifolia. However, it does not alter the concentration of tannins present in the species’ bark

MÉTODOS DE MEDIÇÃO DE ALTURA EM FRAGMENTO DE FLORESTA ESTACIONAL DECIDUAL

Dificuldades relativas à aquisição e à utilização de hipsômetros contribuem para o uso da estimativa visual da altura de árvores em florestas nativas. Diante disso, este trabalho objetivou comparar o método da estimativa visual com balizamento com o hipsômetro digital Haglof na medição de altura de árvores em um fragmento de Floresta Estacional Decidual. A coleta de dados compreendeu 187 árvores contidas em quatro parcelas permanentes. Para as análises comparativas, os dados foram distribuídos em classes de altura e de diâmetro. A estimativa visual com balizamento apresentou confiabilidade na medição da altura de árvores de até 11 m, não diferindo estatisticamente do hipsômetro digital. Entretanto, observou-se uma tendência de subestimação da altura de árvores maiores. Para árvores com altura superior a 11 m, o hipsômetro digital mostrou-se mais confiável.  Palavras-chave: inventário florestal; mensuração florestal; hipsômetro.   METHODS OF MEASUREMENT OF HEIGHT IN FRAGMENT OF DECIDUAL STATE FOREST   ABSTRACT: Difficulties related to the acquisition and use of hypsometers contribute to the use of the visual estimate of the height of trees in native forests. Therefore, this study aimed to compare the method of visual estimation with beaconing with the Haglof digital hypsometer to measure the height of trees in a fragment of Seasonal Deciduous Forest. The data collection comprised 187 trees contained in four permanent plots. For comparative analysis, the data were distributed in height and diameter classes. The visual estimation with beacon showed reliability in measuring the height of trees up to 11 m, not differing statistically from the digital hypsometer. However, there was a tendency to underestimate the height of larger trees. For trees higher than 11 m, the digital hypsometer was more reliable. Keywords: forest inventory; forest measurement; hypsometer

Secagem de toras de clones de Eucalyptus urograndis em estufa solar

Drying is an important stage in the wood industrialization process, with the purpose of improving the quality of the material. However, it is an expensive process, and there is a need to reduce its costs by using methods that require less investment. Thus, the objectives of this study were to evaluate the efficiency of a solar drying oven for drying Eucalyptus urograndis clone logs installed in the municipality of Macaíba, state of Rio Grande do Norte, in order to check whether the region is suitable for this practice; and ii) to evaluate the influence of different log diameter classes in the drying process. 1.50m logs were sectioned and separated according to four diametric classes. They were then weighed and placed in a solar oven, with daily measurements of air temperature and relative humidity and biweekly weighings during the observation period until they reached the fiber saturation point. The data were submitted to regression analysis, applying the variable selection procedure. At 35 days, all logs had already reached the PSF. However, the diameter measurements did not significantly affect the drying process, which proved to be efficient when compared to conventional and natural methods. Therefore, the solar kiln drying of logs becomes a viable method for the region.A secagem é uma etapa importante no processo da industrialização da madeira, tendo como finalidade melhorar a qualidade do material. Porém, é um processo oneroso havendo a necessidade da redução dos seus custos, por meio de métodos que demandem menos investimento. Desse modo, os objetivos deste estudo foram avaliar a eficiência de estufa solar na secagem de toras de clones de Eucalyptus urograndis instalada no município de Macaíba, estado do Rio Grande do Norte, com o intuito de verificar se a região é adequada para esta prática; e ii) avaliar a influência de diferentes classes de diâmetro das toras no processo de secagem. Foram seccionadas toras de 1,50m e separadas em função de quatro classes de diamétricas. Em seguida foram pesadas e acondicionadas em estufa solar, sendo realizado medições diárias da temperatura e umidade relativa do ar e pesagens quinzenais durante o período de observação até que atingissem o ponto de saturação das fibras. Os dados foram submetidos a análise de regressão, aplicando-se o procedimento de seleção de variáveis. Aos 35 dias, todas as toras já haviam atingido o PSF. Entretanto, as medidas do diâmetro não afetaram significativamente na secagem, que se demonstrou eficiente quando comparada aos métodos convencionais e naturais. Portanto a secagem de toras em estufa solar torna-se um método viável para região

Mimosa caesalpiniifolia Benth. como alternativa para produção de madeira no Nordeste do Brasil

Mimosa caesalpiniifolia is a native species from Northeast Brazil, with good soil and climate adaptation, fast growth and potential for multiple use. Because of these characteristics, it has been considered a promising species for forestry. This work aimed to evaluate the growth and productivity of Mimosa caesalpiniifolia at 75 months of age, in a homogeneous plantation located in the state of Rio Grande do Norte, Northeastern Brazil. The data were collected in a 0.05 ha plot with 84 individuals, submitted to thinning at 12 and 55 months. The variables height (H), diameter at breast height (DBH), and diameter at base (DAB) were evaluated. The productivity of the plantation was estimated in terms of total volume (m3) and stacked volume (st), number of stems and mean annual increment (MAI). On average, the individuals were 4.85 m tall, 12.05 cm in diameter at the base (DAB) and 8.42 cm DBH. Each individual presented an average of 6.07 stems. The estimated productivity was 43.88 m³ ha-1, with MAI of 7.02 m³ ha-1 year-1, and the estimated stacked wood volume was 111.89 st ha-1. The results showed the high potential of the species for the production of stakes and fence posts, as well as for the production of kindling and firewood, aiming at the use of all the biomass produced. Therefore, the planting of this species for the production of wood serves as an alternative to meet demands in the Northeast of Brazil.Mimosa caesalpiniifolia é uma espécie nativa do Nordeste do Brasil, com boa adaptação edafoclimática, crescimento rápido e potencial de uso múltiplo. Por causa dessas características, tem sido considerada uma espécie promissora para a silvicultura. Este trabalho teve como objetivo avaliar o crescimento e produtividade de Mimosa caesalpiniifolia aos 75 meses de idade, em plantio homogêneo localizado no estado do Rio Grande do Norte, Nordeste do Brasil. Os dados foram coletados em um talhão de 0.05 ha com 84 indivíduos, submetidos ao raleio aos 12 e 55 meses. Foram avaliadas as variáveis altura, diâmetro a altura do peito (DAP) e diâmetro na base da árvore (DNB). A produtividade do plantio foi estimada em termos de volume total e volume empilhado, número de fustes e incremento médio anual (IMA). Em média, os indivíduos apresentaram 4,85 m de altura, 12,05 cm de diâmetro na base (DAB) e 8,42 cm de DAP. Cada indivíduo apresentou em média 6,07 fustes. A produtividade estimada foi de 43,88 m³ ha-1, com IMA de 7,02 m³ ha-1 ano-1, e o volume de madeira empilhada estimado foi de 111,89 st ha-1. Os resultados demonstraram elevado potencial da espécie para produção de estacas e mourões, bem como para a produção de estacotes e lenha, visando o aproveitamento de toda a biomassa produzida. Portanto, o plantio dessa espécie para a produção de madeira serve como alternativa para atender demandas no Nordeste do Brasil

Tannin-rich Tree Bark Extracts Inhibit the Development of Bacteria Associated with Bovine Mastitis

Condensed tannins were quantified in the barks of selected tree species, and the antibacterial activity of these substances against clinical and subclinical isolates of bovine mastitis were evaluated. Tree barks from Mimosa tenuiflora, Mimosa caesalpiniifolia, Anacardium occidentale, and Stryphnodendron adstringens were used, as well as commercial tannin from Acacia mearnsii. The tannins were extracted using a mixture of ethyl alcohol and acetone. The moisture content (MC), Stiasny index (SI), total solids content (TSC), and condensed tannins (CT) were measured. The evaluation of antimicrobial activity was determined by applying the disk diffusion test. The species that showed the highest CT were M. tenuiflora and A. occidentale, with 37.3% and 37.3%, respectively. The highest SI were obtained by the species A. occidentale and M. caesalpiniifolia, with values above 90%. The bacterium with the lowest resistance to the use of tannins was Streptococcus uberis. A. mearnsii was the only one capable of inhibiting the growth of Escherichia coli, with a mean inhibition halo of 9 mm. All species under study showed high values of condensed tannins in their barks. In addition to showing good performance as antimicrobial agents, these tannins indicated potential applications in the development of natural medicines for the treatment of bovine mastitis

MÉTODOS DE MEDIÇÃO DE ALTURA EM FRAGMENTO DE FLORESTA ESTACIONAL DECIDUAL

Dificuldades relativas à aquisição e à utilização de hipsômetros contribuem para o uso da estimativa visual da altura de árvores em florestas nativas. Diante disso, este trabalho objetivou comparar o método da estimativa visual com balizamento com o hipsômetro digital Haglof na medição de altura de árvores em um fragmento de Floresta Estacional Decidual. A coleta de dados compreendeu 187 árvores contidas em quatro parcelas permanentes. Para as análises comparativas, os dados foram distribuídos em classes de altura e de diâmetro. A estimativa visual com balizamento apresentou confiabilidade na medição da altura de árvores de até 11 m, não diferindo estatisticamente do hipsômetro digital. Entretanto, observou-se uma tendência de subestimação da altura de árvores maiores. Para árvores com altura superior a 11 m, o hipsômetro digital mostrou-se mais confiável.  Palavras-chave: inventário florestal; mensuração florestal; hipsômetro.   METHODS OF MEASUREMENT OF HEIGHT IN FRAGMENT OF DECIDUAL STATE FOREST   ABSTRACT: Difficulties related to the acquisition and use of hypsometers contribute to the use of the visual estimate of the height of trees in native forests. Therefore, this study aimed to compare the method of visual estimation with beaconing with the Haglof digital hypsometer to measure the height of trees in a fragment of Seasonal Deciduous Forest. The data collection comprised 187 trees contained in four permanent plots. For comparative analysis, the data were distributed in height and diameter classes. The visual estimation with beacon showed reliability in measuring the height of trees up to 11 m, not differing statistically from the digital hypsometer. However, there was a tendency to underestimate the height of larger trees. For trees higher than 11 m, the digital hypsometer was more reliable. Keywords: forest inventory; forest measurement; hypsometer

Bairros biodiversos: uma ferramenta para conservação ex-situ

As florestas urbanas apresentam infinidades de benefícios, podendo atuar como uma ferramenta para conservação ex-situ. O estudo teve como objetivo realizar o diagnóstico de uma floresta urbana pública, com o intuito de oferecer subsídios para o manejo e garantir que a arborização possa cumprir com funções sociais, estéticas e ecológicas. O levantamento foi desenvolvido em 6 praças e 5 canteiros centrais do Bairro Jardins. As espécies foram classificadas quanto a sua origem fitogeográfica e forma de dispersão de sementes. Foram determinados os índices de diversidade de Shannon-Weaver (H’), dominância de Simpson (D’) e equabilidade de Pielou (J). Ao todo foram identificados 507 indivíduos, pertencentes a 12 famílias e distribuídos em 29 espécies, sendo 13 nativas e 16 exóticas. A família que apresentou maior riqueza em número de espécies foi a Fabaceae (36%). Quanto à classificação da síndrome de dispersão, a mais ocorrente foi por zoocoria (52%). Os índices ecológicos calculados do bairro mostraram ocorrência de média diversidade de espécies (H’ = 2.2284), dominância elevada (D’ = 0.7899) e médio equilíbrio do número de indivíduos (J) de 0.6552. Embora o bairro Jardins tenha sido planejado, a floresta urbana nessa área ainda precisa de melhorias; tais como medidas de incentivo que podem promover a biodiversidade e a aplicação de conservação ex-situ

Photoluminous Response of Biocomposites Produced with Charcoal

Due to the possible effects of global warming, new materials that do not have a negative impact on the environment are being studied. To serve a variety of industries and outdoor applications, it is necessary to consider the impact of photoluminosity on the performance of biocomposites in order to accurately assess their durability characteristics and prevent substantial damage. Exposure to photoluminosity can result in adverse effects such as discoloration, uneven surface, loss of mass, and manipulation of the intrinsic mechanical properties of biocomposites. This study aims to evaluate general charcoal from three pyrolysis temperatures to understand which charcoal is most suitable for photoluminosity and whether higher pyrolysis temperatures have any significant effect on photoluminosity. Porosity, morphology, Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy of charcoal were analyzed. Charcoal obtained at a temperature of 800 °C demonstrates remarkable potential as a bioreinforcement in polymeric matrices, attributable to its significantly higher porosity (81.08%) and hydrophobic properties. The biocomposites were characterized for flexural strength, tensile strength, scanning electron microscopy (SEM), FTIR, and x-ray diffraction (XRD). The results showed an improvement in tensile strength after exposure to photoluminosity, with an increase of 69.24%, 68.98%, and 54.38% at temperatures of 400, 600, and 800 °C, respectively, in relation to the treatment control. It is notorious that the tensile strength and modulus of elasticity after photoluminosity initially had a negative impact on mechanical strength, the incorporation of charcoal from higher pyrolysis temperatures showed a substantial increase in mechanical strength after exposure to photoluminosity, especially at 800 °C with breaking strength of 53.40 MPa, and modulus of elasticity of 4364.30 MPA. Scanning electron microscopy revealed an improvement in morphology, with a decrease in roughness at 800 °C, which led to greater adhesion to the polyester matrix. These findings indicate promising prospects for a new type of biocomposite, particularly in comparison with other polymeric compounds, especially in engineering applications that are subject to direct interactions with the weather