8 research outputs found

    Natural durability of five tropical wood species in field decay tests

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    Measuring the natural resistance of wood is fundamental for proper use. The natural durability of five tropical wood species was investigated by field decay testing during exposure for 360 days. Wood logs (length of 0,5 m; diameter of 8 cm - 12 cm) were used in this study. The mass loss and decay index were calculated and visual analysis during the exposure time was performed for all samples. The samples presented evidence of two different groups concerning natural durability. The species in the first group (Mimosa caesalpiniifolia, Mimosa ophthalmocentra, and Mimosa tenuiflora) showed the highest resistance to biodeterioration, better or similar performance compared to treated eucalyptus wood (as control). The other group (Aspidosperma pyrifolium and Cordia oncocalyx) had lower natural resistance in outdoor service, being more susceptible to decay. In general, the wood of the first group is indicated for outdoor uses that require medium or prolonged exposure, such as timber stakes and fence posts

    Tannic extract efficiency combined or not with boric acid on protection of Ceiba pentandra wood against xylophagous termite

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    Dentre os métodos que vêm sendo testados para minimizar a lixiviação de compostos de boro na madeira, destaca-se sua combinação com taninos vegetais. Aos taninos vegetais é atribuída a durabilidade natural da madeira de algumas espécies, indicando sua potencialidade como preservativo natural. Neste estudo, avaliou-se o rendimento de taninos condensados provenientes da casca de Mimosa tenuiflora em extração realizada com água destilada, comparando-o ao da extração envolvendo a inclusão de sulfito de sódio, assim como a eficiência de extratos tânicos sulfitados, combinados ou não com ácido bórico, na melhoria da resistência da madeira de Ceiba pentandra ao térmita xilófago Nasutitermes corniger, por meio de ensaio de preferência alimentar. Extrato tânico obtido com a inclusão de sulfito de sódio à água teve melhor rendimento em taninos condensados. De maneira geral, a impregnação da madeira com o extrato tânico sulfitado proporcionou o mesmo comportamento quando comparada à aplicação do ácido bórico, sendo os melhores resultados verificados quando ambos foram utilizados conjuntamente. No entanto, depois de aplicado na madeira, o extrato tânico foi lixiviado e não favoreceu a redução da lixiviação do ácido bórico. Apesar da potencialidade do uso do extrato tânico ao cupim xilófago, estudos adicionais fazem-se necessários.Palavras-chave: Biodeterioração da madeira; térmitas xilófagos; Nasutitermes corniger. AbstractTannic extract efficiency combined or not with boric acid on protection of Ceiba pentandra wood against xylophagous termite. Among the methods tested to reduce the leaching of boron compounds in wood, it can be highlighted their combination with vegetable tannins. It is attributed the natural durability of some species of wood to vegetable tannins, pointing to their potentiality as natural wood preservatives. This research evaluated the efficiency of condensed tannins from bark of Mimosa tenuiflora extract with distilled water, compared to another extract added of sodium sulfite. It also evaluated the efficiency of sulfited tannin extracts, combined or not with boric acid in order to improve the resistance of Ceiba pentandra against the xylophagous termite Nasutitermes corniger by feeding test. Tannic extract obtained by adding sodium sulfite to distilled water revealed better yield compared to condensed tannin extraction. In general, impregnation of wood with tannin extract presented the same behavior as compared to application of boric acid, with best results observed when both them were simultaneously used. However, after applied to wood, tannin extracted was leachable and it did not favor the boric acid leaching. Despite the potential use of tannic extract against the xylophagous termite, additional studies are required for a best evaluation.Keywords: Wood biodeterioration; xilophogous termites; Nasutitermes corniger.AbstractAmong the methods tested to reduce the leaching of boron compounds in wood, it can be highlighted their combination with vegetable tannins. It is attributed the natural durability of some species of wood to vegetable tannins, pointing to their potentiality as natural wood preservatives. This research evaluated the efficiency of condensed tannins from bark of Mimosa tenuiflora extract with distilled water, compared to another extract added of sodium sulfite. It also evaluated the efficiency of sulfited tannin extracts, combined or not with boric acid in order to improve the resistance of Ceiba pentandra against the xylophagous termite Nasutitermes corniger by feeding test. Tannic extract obtained by adding sodium sulfite to distilled water revealed better yield compared to condensed tannin extraction. In general, impregnation of wood with tannin extract presented the same behavior as compared to application of boric acid, with best results observed when both them were simultaneously used. However, after applied to wood, tannin extracted was leachable and it did not favor the boric acid leaching. Despite the potential use of tannic extract against the xylophagous termite, additional studies are required for a best evaluation.Keywords: Wood biodeterioration; xilophogous termites; Nasutitermes corniger

    Tannins quantification in barks of Mimosa tenuiflora and Acacia mearnsii

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    Em função de sua complexidade química, há diversas metodologias de quantificação dos taninos vegetais. Neste sentido, o presente estudo teve como objetivo quantificar as substâncias tânicas e não-tânicas presentes nas cascas de jurema-preta (Mimosa tenuiflora) e de acácia-negra (Acacia mearnsii) por dois métodos distintos. A partir das partículas de casca de ambas as espécies, foram geradas soluções analíticas utilizando um extrator do tipo camisa de vapor, sendo a solução analisada pelos métodos de Stiasny e do pó de pele (não cromado). Para ambas as espécies, os teores de tânicos foram superiores quando analisados pelo método de pó de pele, atingindo 47,8 e 24,1% para A. mearnsii e M. tenuiflora, respectivamente. Pelo método de Stiasny, o teor de taninos condensados foi de 39,0% para A. mearnsii e 15,5% para M. tenuiflora. Apesar dos melhores resultados obtidos para a A. mearnsii, a casca de M. tenuiflora também apresentou grande potencialidade em função da considerável quantidade de tânicos e da disponibilidade da espécie no bioma Caatinga.Due to its chemical complexity, there are several methodologies for vegetable tannins quantification. Thus, this work aims at quantifying both tannin and non-tannin substances present in the barks of Mimosa tenuiflora and Acacia mearnsii by two different methods. From bark particles of both species, analytical solutions were produced by using a steam-jacketed extractor. The solution was analyzed by Stiasny and hide-powder (no chromed) methods. For both species, tannin levels were superior when analyzed by hide-powder method, reaching 47.8% and 24.1% for A. mearnsii and M. tenuiflora, respectively. By Stiasny method, the tannins levels considered were 39.0% for A. mearnsii, and 15.5% for M. tenuiflora. Despite the best results presented by A. mearnsii, the bark of M. tenuiflora also showed great potential due to its considerable amount of tannin and the availability of the species at Caatinga biome

    PRODUTIVIDADE EM CASCA E TANINOS CONDENSADOS DE JUREMA-PRETA

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    Espécie vegetal de ampla distribuição geográfica no bioma Caatinga, a Mimosa tenuiflora (Willd.) Poir., vem sendo explorada, principalmente, para produção de energia, apesar de possuir considerável teor de taninos. Com base nisto, no presente estudo analisou-se a produtividade da espécie em relação à produção de casca e seu rendimento em taninos condensados. Para isso utilizou-se árvores adultas que foram selecionadas aleatoriamente na Fazenda NUPEÁRIDO, localizada no município de Patos, PB, Brasil, das quais se removeu a casca desde a base até a porção superior dos galhos. As cascas foram submetidas à secagem, para na sequência serem pesadas, fragmentadas, classificadas e submetidas à extração em autoclave sob diferentes tempos (1, 2 e 3 horas), com posterior quantificação da porção tânica do extrato líquido. Considerando a massa anidra, obteve-se aproximadamente 3,7 kg de casca por árvore. O tempo de extração de 3 horas foi o que apresentou os melhores resultados no rendimento em taninos condensados, atingindo 17,3%. Tais resultados fornecem subsídios efetivos para futuras análises, com relação à rentabilidade em produção e questões econômicas, favorecendo para o emprego industrial da espécie. Palavras-chave: Mimosa tenuiflora (Willd.) Poir., rendimento em tânicos, bioma Caatinga.   PRODUCTIVITY ON BARK AND CONDENSED TANNINS OF JUREMA-PRETA ABSTRACT Mimosa tenuiflora (Willd.) Poir., as a species of plant widely distributed in the Caatinga biome, has been explored mainly for energy production, despite having considerable tannin content. Based on that, this study aims to analyze the productivity of such species in relation to the production of bark and its income in condensed tannins. To do that, adult plants were randomly selected at NUPEÁRIDO Farm, in Patos, PB, Brazil, having their bark removed from the base to the upper branches of the plant. Barks were dried in order to be weighed, fragmented, classified, and submitted to extraction in an autoclave under different times (1, 2, and 3 hours) with subsequent quantification of tannin portion from the extracted liquid. Considering the dry mass, about 3.7 kg of bark per tree were obtained. The 3-hour extraction time showed the best results considering the income in condensed tannins, reaching 17.3%. Such results provide effective support for future analysis with respect to profitability in production and economic issues, favoring for industrial use of this species. Keywords: Mimosa tenuiflora (Willd.) Poir., performance in tannins, Caatinga biome. DOI: http://dx.doi.org/10.14583/2318-7670.v03n02a0

    Brazilian Flora 2020: Leveraging the power of a collaborative scientific network

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    International audienceThe shortage of reliable primary taxonomic data limits the description of biological taxa and the understanding of biodiversity patterns and processes, complicating biogeographical, ecological, and evolutionary studies. This deficit creates a significant taxonomic impediment to biodiversity research and conservation planning. The taxonomic impediment and the biodiversity crisis are widely recognized, highlighting the urgent need for reliable taxonomic data. Over the past decade, numerous countries worldwide have devoted considerable effort to Target 1 of the Global Strategy for Plant Conservation (GSPC), which called for the preparation of a working list of all known plant species by 2010 and an online world Flora by 2020. Brazil is a megadiverse country, home to more of the world's known plant species than any other country. Despite that, Flora Brasiliensis, concluded in 1906, was the last comprehensive treatment of the Brazilian flora. The lack of accurate estimates of the number of species of algae, fungi, and plants occurring in Brazil contributes to the prevailing taxonomic impediment and delays progress towards the GSPC targets. Over the past 12 years, a legion of taxonomists motivated to meet Target 1 of the GSPC, worked together to gather and integrate knowledge on the algal, plant, and fungal diversity of Brazil. Overall, a team of about 980 taxonomists joined efforts in a highly collaborative project that used cybertaxonomy to prepare an updated Flora of Brazil, showing the power of scientific collaboration to reach ambitious goals. This paper presents an overview of the Brazilian Flora 2020 and provides taxonomic and spatial updates on the algae, fungi, and plants found in one of the world's most biodiverse countries. We further identify collection gaps and summarize future goals that extend beyond 2020. Our results show that Brazil is home to 46,975 native species of algae, fungi, and plants, of which 19,669 are endemic to the country. The data compiled to date suggests that the Atlantic Rainforest might be the most diverse Brazilian domain for all plant groups except gymnosperms, which are most diverse in the Amazon. However, scientific knowledge of Brazilian diversity is still unequally distributed, with the Atlantic Rainforest and the Cerrado being the most intensively sampled and studied biomes in the country. In times of “scientific reductionism”, with botanical and mycological sciences suffering pervasive depreciation in recent decades, the first online Flora of Brazil 2020 significantly enhanced the quality and quantity of taxonomic data available for algae, fungi, and plants from Brazil. This project also made all the information freely available online, providing a firm foundation for future research and for the management, conservation, and sustainable use of the Brazilian funga and flora

    NEOTROPICAL ALIEN MAMMALS: a data set of occurrence and abundance of alien mammals in the Neotropics

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    Biological invasion is one of the main threats to native biodiversity. For a species to become invasive, it must be voluntarily or involuntarily introduced by humans into a nonnative habitat. Mammals were among first taxa to be introduced worldwide for game, meat, and labor, yet the number of species introduced in the Neotropics remains unknown. In this data set, we make available occurrence and abundance data on mammal species that (1) transposed a geographical barrier and (2) were voluntarily or involuntarily introduced by humans into the Neotropics. Our data set is composed of 73,738 historical and current georeferenced records on alien mammal species of which around 96% correspond to occurrence data on 77 species belonging to eight orders and 26 families. Data cover 26 continental countries in the Neotropics, ranging from Mexico and its frontier regions (southern Florida and coastal-central Florida in the southeast United States) to Argentina, Paraguay, Chile, and Uruguay, and the 13 countries of Caribbean islands. Our data set also includes neotropical species (e.g., Callithrix sp., Myocastor coypus, Nasua nasua) considered alien in particular areas of Neotropics. The most numerous species in terms of records are from Bos sp. (n = 37,782), Sus scrofa (n = 6,730), and Canis familiaris (n = 10,084); 17 species were represented by only one record (e.g., Syncerus caffer, Cervus timorensis, Cervus unicolor, Canis latrans). Primates have the highest number of species in the data set (n = 20 species), partly because of uncertainties regarding taxonomic identification of the genera Callithrix, which includes the species Callithrix aurita, Callithrix flaviceps, Callithrix geoffroyi, Callithrix jacchus, Callithrix kuhlii, Callithrix penicillata, and their hybrids. This unique data set will be a valuable source of information on invasion risk assessments, biodiversity redistribution and conservation-related research. There are no copyright restrictions. Please cite this data paper when using the data in publications. We also request that researchers and teachers inform us on how they are using the data

    Núcleos de Ensino da Unesp: artigos 2009

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