19 resultados para Bambusa


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Dendrocalamus strictus and Bambusa arundinacea are monocarpic, gregariously flowering species of bamboo, common in the deciduous forests of the State of Karnataka in India. Their populations have significantly declined, especially since the last flowering. This decline parelleis increasing incidence of grazing, fire and extraction in recent decades. Results of an experiment in which the intensities of grazing and fire were varied, indicate that while grazing significantly depresses the survival of seedlings and the recruitment of new eulms of bamboo clumps, fire appeared to enhance seedling survival, presumably by reducing competition of lass fire-resistant species. New shoots of bamboo are destroyed by insects and a variety of herbivorous mammals. In areas of intense herbivore pressure, a bamboo clump initiates the production of a much larger number of new culrm, but results in many fewer and shorter intact culms. Extraction renders the new shoots more susceptible to herbivore pressure by removal of the protective covering of branches at the base of a bamboo clump. Hence, regular and extensive extraction by the paper mills in conjuction with intense grazing pressure strongly depresses the addition of new culms to bamboo clumps. Regulation of grazing in the forest by domestic livestock along with maintenance of the cover at the base of the clumps by extracting the culms at a higher level should reduce the rate of decline of the bamboo stocks.

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This paper reports twelve acarine species belonging to eleven genera in five families, associated with Bambusa sp. (Poaceae), in a woody area from São Paulo State, Brazil. Four species of Tetranychidae (Monoceronychus bambusicola, sp.n.. Oligonychus santoantoniensis, sp.n.. Schizotetranychus longirostris, sp.n. and S. paraelymus, sp.n.) are regarded as new. The genus Cheletomimus Oudemans, 1904 (Cheyletidae) is recorded for the first time to South America.

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Bambusa textilis is widely used in popular medicine to treat all kinds of wound inflammation, chronic fever, pulmonary and infectious diseases. The aim of this study was to compare the chemical composition of the extracts of B. textilis leaves obtained by three different extraction methods: solid/liquid extraction, Soxhlet and Clevenger system using gas chromatography with flame ionization detector (GC-FID) and gas chromatography with mass spectrometry (GC-MS) analyses. The analytical characteristics of the extracts showed some differences and the GC-MS analysis indicated the presence of higher concentrations of nitro compounds and alkalis. © VSP 2005.

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Introduction: Bamboos belong to the family Graminae, Bambusoidae subfamily, represented by about 1,250 species worldwide. Originally employed in construction and power, are currently the subject of investigations related to its therapeutic properties in neoplasms. The main species used for therapeutic purposes based on popular knowledge are: Phyllostachys nigra; Bambusa breiflora; tuldoides Bambusa textilis and Bambusa. The literature on the therapeutic action of bamboo species is scarce, but recent studies report a promising effect in the treatment of cancer and other chronic diseases. Objective: This study aimed to evaluate qualitatively the phytochemical composition of plant extract obtained from the leaves of the bamboo species Bambusa textilis, comparing this composition from vegetable leaves with 18 and 24 months of age. Methodology: After collecting plant leaves with 18 or 24 months, they were identified and submitted to drying and milling. For qualitative analysis of its components were employed methods of macroscopic evaluation (mucilage), method of benzoin (resin), reaction Shinoda (flavonoids), reaction with gelatin solution (tannins), boiling and foaming (saponins) and jobs of reactive Wagner, Bertrand, Dragendorff, Mayer, picric acid and tannic acid (alkaloids) (Biavatti; MILK, 2007). Results: in the youngest leaves were found positive for alkaloids, flavonoids, resins and saponins. In the leaves of the plant with 24 months were found only alkaloids flavonoids and resins. Conclusion: the composition of vegetable substances were found associated with a significant therapeutic potential difference and the phytochemical composition in comparison with plant leaves 18 or 24 months. Additional studies are needed to quantify these components, as well as the clarification of its action in the fight against cancer and chronic diseases.

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<正> 鳡鱼Elopichthys bambusa(Richardson)是我国特有的一种鲤科鱼类,生活于江河、湖泊的中上层,游泳非常迅速,经常袭击和追捕其他鱼类,是一种咬捕掠食型的凶猛鱼类。由于这种习性,使它的形态,特别是颅骨的结构产生了某些相应变化。为此,(1912)曾据其上颔骨与前上颌骨相愈合等特征,建立了一个与鲤科其他亚科并列的一个类群——Elopichthyini。但至今未见到鳡鱼颅骨结构的系统描述。作者以两尾性成熟个体(标准长分别为930毫米和890毫米)为材料,对鳡鱼的颅骨结构进行了比较观察

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<正> 鳡鱼(Elopichthys bambusa)在我国南北各地分布很广,江汉平原的水系中产得尤其多。牠是一种所谓凶猛鱼类,早在14毫米长的鱼苗时期就已能捕食其他鱼苗。又因为牠生长快、体形大——可达50公斤以上——而且行动迅速善于猎食,所以鳡鱼是我国养鱼业上著名的“害鱼”,也一向是清除的对象。目前我国淡水养鱼业已从池塘饲养发展到湖泊放养。由于湖泊的面积大,池塘渔业所用的清除野鱼的方法象用毒物彻底消灭野鱼等,已不能适用。同时,尽管加强对鳡鱼的

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A Embrapa Amazônia Ocidental possui 7,5 hectares de plantios para teste das espécies Acacia mangium, Acacia auriculiformis, Sclerobium paniculatum (taxi-branco) e Bambusa vulgaris var. vitatta (bambu), que, em experimentos preliminares, mostram-se promissoras para produção de energia.

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As frondes de Rumohra adiantiformis (G.Forest.) Ching, conhecida como “leatherleaf”, “seven-weeks-fern” ou samambaia-preta, são usadas mundialmente em arranjos florais. Na África do Sul e Brasil o comércio da espécie é baseado no extrativismo. No Brasil a coleta é realizada em áreas de Mata Atlântica, sendo que 50% da produção provém das áreas de capoeira das encostas da Serra Geral no Rio Grande do Sul (RS). Atualmente, cerca de 2.000 famílias de agricultores familiares vivem nestas áreas, tendo no extrativismo sua principal fonte de renda. No entanto no RS a coleta, o comércio e o transporte de plantas ornamentais nativas são proibidos, já que nesta zona de transição da Reserva da Biosfera da Mata Atlântica (Maquiné, RS) há grandes restrições quanto à exploração dos recursos naturais. O êxodo rural e o próprio extrativismo estabelecido a partir da década de 70, permitiram a regeneração da Floresta Ombrófila Densa. Como a espécie é característica de estágios sucessionais iniciais, a regeneração florestal está levando à diminuição dos estoques naturais. Este trabalho se propôs a identificar alternativas econômicas para diversificação da economia de famílias de extrativistas, no intuito de minimizar a tensão associada à diminuição dos estoques naturais de samambaia-preta, às dificuldades no manejo da terra e à legislação ambiental. Junto à comunidade extrativista do distrito de Solidão (Maquiné) foram coletados dados etnobiológicos sobre plantas medicinais e plantas relacionadas ao artesanato. As principais espécies identificadas foram: Bambusa tuldoides (taquareira, colmo), Clytostoma sciuripabulum (cipó-branco, caule), Cyperus prolixus (tiririca, partes aéreas), Musa acuminata (bananeira, palha), Scirpus californicus (junco, partes aéreas), Typha dominguensis (taboa, partes aéreas), sendo que Macfadyena dentata (cipó-unha-de-gato, caule), Roupala brasiliensis (carvalho-brasileiro, folhas) e Tillandsia usneoides (barbade- pau, planta inteira) são as espécies prioritárias para a avaliação da sustentabilidade do extrativismo. Os dados etnobiológicos e ecológicos mostram que é possível estabelecer o manejo sustentável da R. adiantiformis. Os maiores entraves para o estabelecimento do manejo sustentado para as espécies identificadas incluem: a) estabelecer as bases de manejo sustentável destas espécies; b) compatibilizar esta atividade extrativista com o atual Código Florestal Estadual. Plantas medicinais não parecem ser uma alternativa viável a curto prazo, enquanto o artesanato requer a adequação da atividade artesanal no meio rural com os direitos à aposentadoria rural.

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Mortality factors that act sequentially through the demographic transitions from seed to sapling may have critical effects on recruitment success. Understanding how habitat heterogeneity influences the causal factors that limit propagule establishment in natural populations is central to assess these demographic bottlenecks and their consequences. Bamboos often influence forest structure and dynamics and are a major factor in generating landscape complexity and habitat heterogeneity in tropical forests. To understand how patch heterogeneity influences plant recruitment we studied critical establishment stages during early recruitment of Euterpe edulis, Sloanea guianensis and Virola bicuhyba in bamboo and non-bamboo stands in the Brazilian Atlantic forest. We combined observational studies of seed rain and seedling emergence with seed addition experiments to evaluate the transition probabilities among regeneration stages within bamboo and non-bamboo stands. The relative importance of each mortality factor was evaluated by determining how the loss of propagules affected stage-specific recruitment success. Our results revealed that the seed addition treatment significantly increased seedling survivorship for all three species. E. edulis seedling survival probability increased in the addition treatment in the two stand types. However, for S. guianensis and V. bicuhyba this effect depended strongly on artificially protecting the seeds, as both species experienced increased seed and seedling losses due to post-dispersal seed predators and herbivores. Propagules of all three species had a greater probability of reaching subsequent recruitment stages when protected. The recruitment of large-seeded V. bicuhyba and E. edulis appears to be much more limited by post-dispersal factors than by dispersal limitation, whereas the small-seeded S. guianensis showed an even stronger effect of post-dispersal factors causing recruitment collapse in some situations. We demonstrated that E. edulis, S. guianensis and V. bicuhyba are especially susceptible to predation during early compared with later establishment stages and this early stage mortality can be more crucial than stand differences as determinants of successful regeneration. Among-species differences in the relative importance of dispersal vs. establishment limitation are mediated by variability in species responses to patch heterogeneity. Thus, bamboo effects on the early recruitment of non-bamboo species are patchy and species-specific, with successional bamboo patches exerting a far-reaching influence on the heterogeneity of plant species composition and abundance. © 2012 Perspectives in Plant Ecology, Evolution and Systematics.

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We analyzed social patterns indicative of the mating system and parental care in a population of the southern bamboo rat (Kannabateomys amblyonyx). This arboreal rodent feeds exclusively on bamboo stems and leaves. We conducted fieldwork from August 2003 to October 2004 in southern Brazil (30 degrees 20`-30 degrees 27`S, 50 degrees 50`-51 degrees 05`W), in patches of introduced Chinese bamboo (Bambusa tuldoides). We captured 18 individuals, 7 of which were adults that received radiotransmitters and were followed from 1 to 12 months. Another 5 animals (adults or subadults) received colored collars. We observed paternal care, delayed juvenile dispersal, and reduced degree of sexual dimorphism, all of which are traits typical of social monogamy. Mated males showed a direct parental behavioral repertoire similar to that of females (with the obvious exception of nursing), including grooming, huddling, and food provisioning. Potential monogamy in this species seems to be a flexible strategy linked to low density of bamboo patches. Females were confined to widely spaced., small home ranges, decreasing the possibility of male defense of and access to > 1 female. The arboreal habits of the species possibly increase the risk of inexperienced young falling from trees or else being depreciated when moving exposed through branches. This risk is probably reduced by the extensive biparental care observed, including the providing of low-energy plant food to young in the nest.

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Southern China, especially Yunnan, has undergone high tectonic activity caused by the uplift of Himalayan Mountains during the Neogene, which led to a fast changing palaeogeography. Previous study shows that Southern China has been influenced by the Asian Monsoon since at least the Early Miocene. However, it is yet not well understood how intense the Miocene monsoon system was. In the present study, 63 fossil floras of 16 localities from Southern China are compiled and evaluated for obtaining available information concerning floristic composition, stratigraphic age, sedimentology, etc. Based on such reliable information, selected mega- and micro-floras have been analysed with the coexistence approach to obtain quantitative palaeoclimate data. Visualization of climate results in maps shows a distinct spatial differentiation in Southern China during the Miocene. Higher seasonalities of temperature and precipitation occur in the north and south parts of Southern China, respectively. During the Miocene, most regions of Southern China and Europe were both warm and humid. Central Eurasia was likely to be an arid center, which gradually spread westward and eastward. Our data provide information about Miocene climate patterns in Southern China and about the evolution of these patterns throughout the Miocene, and is also crucial to unravel and understand the climatic signals of global cooling and tectonic uplift.