Structural variations in root and stem wood of Styrax (Styracaceae) from Brazilian forest and cerrado

The genus Styrax L. (Styracaceae) has a wide distribution in Brazil, occurring in diverse ecosystems. To get a better insight into the ecological adaptations of wood structure, we studied two species, S. camporum and S.ferrugineus from the cerrado, and three species, S. latifolium, S. martii and S. leprosus from the Atlantic forest. For each species, the wood of root and stem was analyzed separately and observations included qualitative as well as quantitative wood characteristics. The results show that there were significant anatomical differences between the forest and cerrado species as well as between the root and stem wood within single species. Quantitatively, the most informative features in the root wood that separated the forest from the cerrado, species were diameter, length and number of vessels, length of fibres, and width and frequency of rays. In the stem wood, length and frequency of vessels, length of fibres, and width and frequency of rays were the most informative features. In contrast to the forest species, which had larger vessel diameters in their stem wood, the cerrado species had larger vessel diameters in their root wood. The calculated vulnerability index indicates that all Sryrax species have adaptations to mesic conditions. The cerrado species had the smallest index values, which could be related to the seasonally dry condition of this environment.

Morfologia de nectários em Leguminosae senso lato em áreas de caatinga no Brasil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Perforated ray cells in the wood of roots and branches of cerrado species from Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Stem protective tissue in Erythroxylum tortuosum (Erythroxylaceae), a fire tolerant species from cerrado

The origin and structure are described of the secondary protective tissue in the stem of Erythorxylum tortuosum Mart., a fire tolerant shrubby species common in Brazilian cerrado. The highly tortuous stems are covered with thick bark which is more developed at the base of the stem. After fire in the cerrado, rhytidome fragments of the burned stem flake off, revealing newly formed cork. The first periderm appears near of the terminal buds and is iniated by periclinal divisions in subepidermal cells giving rise to radial rows of cells. The first phellogen is discernible only after the differentiation of the several radial rows of cork cells. Other phellogens have their origin in successively deeper layers of the cortex. The sucessive periderms are discontinuous around the circumference. The collapsed cells with phenolic substances and the accumulated dead cells cause the formation of discontinuous blackish lines, which delimit the sucessive periderms in the rhytidome. The rhytidome contains large quantities of sclereids developed from cell wall thickening of cortex cells. The occurrence of periderm, in the young parts of the stem and of rhytidome in the older parts represents pyrophytic characteristics and may explain, in part, the fire tolerance of this species.

Construção coletiva de uma trilha ecológica no cerrado: pesquisa participativa em educação ambiental

Dentre os muitos temas ambientais que podem ser problematizados pela Educação Ambiental encontra-se a proteção aos ecossistemas. Definiu-se como tema, num projeto de Educação Ambiental, o Cerrado, bioma amplamente degradado por ações antrópicas e que faz parte do ambiente natural de Botucatu, interior de São Paulo. Com o objetivo de despertar um olhar crítico-ambiental, visando a integração do ambiente natural e urbano, o projeto, realizado com alunos da 8ª série do Ensino Fundamental, teve como eixo a construção de uma Trilha Ecológica no Cerrado. Todo o processo de planejamento, realização e avaliação da trilha foi participativo: os participantes estudaram as características do Cerrado; identificaram, na área, as espécies remanescentes; discutiram as condições de conservação da área, e tomaram decisões sobre a construção da trilha como recurso educativo. Problematizaram, coletivamente, a interação comunidade-ambiente, articulando consciência ambiental e ação educativa, concluindo sobre o potencial desencadeador deste recurso para reflexões sobre temas socioambientais. O grupo teve a oportunidade de vivenciar um trabalho educativo com crianças da educação infantil, concretizando a trilha como recurso didático-pedagógico na aproximação visitantes-educandos-ambiente.

Antimicrobial activity of some medicinal plants of the Cerrado, Brazil

In order to determine the potential of Cerrado plants as sources of antimicrobial activity, the phytochemical screening of ethanol extracts from Virola surinamensis, Qualea grandiflora, Alchornea castaneifolia, Hancornia speciosa and Curatella americana traditionally used in folk medicine are reported. Copyright (C) 2008 John Wiley & Sons, Ltd.

Qualea grandiflora, a Brazilian Cerrado medicinal plant presents an important antiulcer activity

Qualea grandiflora is one of the species widely used in folk medicine to treat gastric ulcers in Cerrado of the central region of Brazil. The hydroalcoholic extract of bark (HE) of Qualea grandiflora was investigated for their ability to prevent and heal lesions in the gastric mucosa. The oral administration of HE exhibited antiulcer activity decreasing the ulcerative index induced by HCl/ethanol solution, indomethacin/bethanechol and stress. In the Shay model, results showed that HE (p.o.) only reduced the severity of gastric lesions without effects on pH, gastric acidity or volume. When given by intraduodenal route, HE changed the pH, but did not modify the other parameters of the gastric juice. These data were in accordance with those obtained when HE was administered orally for 14 days after gastric ulcers were induced by acetic acid in rats. HE presented healing process in subacute gastric ulcer induced by acetic acid in rats. Moreover, histological examinations showed the simple columnar epithelium, lamina propria with simple branched tubular glandules with dilated lumen and large amounts of mucus secretion. Phytochemical investigation of HE led to the detection of terpenes, steroids, saponins, phenolic compounds and tannins in this extract, which may be involved in the observed activity. (c) 2005 Elsevier B.V.. All rights reserved.

Qualidade dos méis produzidos por Melipona fasciculata Smith da região do cerrado maranhense

The honey of Melipona fasciculata is few known in terms of composition, and therefore generally associated with the characteristics of the honey of Apis mellifera. This study contributes to the knowledge of the physico-chemical characteristics of honey of M. fasciculata of the municipalities of Barra do Corda, Jenipapo dos Vieiras, Fernando Falcão, Carolina and Riachão, in cerrado region from Maranhão. The parameters studied were: moisture, pH, acidity, reducing sugars, apparent sucrose, hydroxymethylfurfural, diastase activity, insoluble solids, ash and color. Some of the observed patterns may conform to the established for A. mellifera, but others must be accompanied by a specific legislation.

Helminths from Lizards (Reptilia: Squamata) at the Cerrado of Goias State, Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Helminths from Seven Species of Lizards (Reptilia: Squamata) at the Cerrado of Mato Grosso do Sul State, Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The effect of the land use on phytoplankton assemblages of a Cerrado stream (Brazil)

OBJETIVO: Nosso objetivo foi investigar se o uso do solo do ambiente terrestre adjacente influencia a estrutura das assembleias fitoplanctônicas (composição, riqueza, diversidade e abundância) e biomassa (clorofila-a) em um riacho de Cerrado durante diferentes períodos do ano. MÉTODOS: Os trabalhos de campo foram realizados trimestralmente durante dois anos. RESULTADOS: As variáveis físico-químicas que melhor indicaram as diferenças nas condições da água foram condutividade, oxigênio dissolvido e transparência. Também houve um notável aumento na concentração de nitrogênio, fósforo e material em suspensão na água durante o verão devido aos efeitos da pluviosidade. As assembleias fitoplanctônicas foram compostas por 64 espécies. Cryptophyceae foi o grupo mais abundante, seguido por Bacillariophyceae. Para ambos os anos, a riqueza e a diversidade foram maiores durante a primavera e no outono, enquanto que a abundância do fitoplâncton e a concentração de clorofila-a foram mais elevados durante o outono e verão. A análise de agrupamento e a analise de correspondência canônica mostraram que a sazonalidade e o uso do solo são fatores importantes na estruturação das assembleias ao longo do ano. As alterações nas assembleias fitoplanctônicas ocorreram provavelmente em função da variação na intensidade e freqüência da mistura da água e da entrada de nutrientes oriundo do sistema terrestre adjacente para o aquático. CONCLUSÃO: A estrutura das assembleias fitoplanctônicas mostrou ser altamente influenciada pelo uso do solo, corroborando com a hipótese inicial do trabalho.

Influência da ação antrópica sobre a fauna de macroinvertebrados aquáticos em riachos de uma região de cerrado do sudoeste do Estado de São Paulo

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Predation of herps by spiders (Araneae) in the Brazilian Cerrado.

Two events of predation of herps by spiders in the Brazilian Cerrado are reported here. A lizard Micrablepharus atticolus (Sauria: Gymnophthalmidae) was found being preyed upon by Lycosa erythrognatha (Araneae: Lycosidae) and a frog Physalaemus cuvieri (Anura: Leiuperidae) was seen being preyed upon by Ancylometes sp. (Araneae: Ctenidae).