6 research outputs found

    Análise físico-química do óleo-resina e variabilidade genética de copaíba na Floresta Nacional do Tapajós

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    O objetivo deste trabalho foi caracterizar o óleo-resina da copaíba (Copaifera reticulata) e estimar, por meio de marcadores microssatélites, a variabilidade genética da espécie na Floresta Nacional do Tapajós, PA. A amostragem foi realizada em duas áreas, distanciadas de 5 km, em 136 árvores. A diversidade genética foi avaliada com seis marcadores microssatélites derivados de C. langsdorffii, e o óleo obtido de 30 árvores (15 de cada área) foi caracterizado em termos físicos e químicos. O óleo C. reticulata apresenta aspecto líquido, fino, odor fraco e de coloração amarelo-dourada (73,3% das plantas), com viscosidade muito variável (18 a 187 Pa-s) e densidade média de 0,975±0,049 g cm-3. O índice de acidez variou de 9,62 a 10,17 mg g-1 de KOH e o de saponificação de 100,63 a 109,84 mg g-1. A análise molecular identificou 78 alelos, com média de 13 por loco. A heterozigosidade esperada variou 0,59 a 0,85 (média de 0,75), com nível de endogamia de 0,375 a 0,419. Houve pouca diferenciação genética entre as populações das diferentes áreas de coleta (F ST = 0,030), mas a variabilidade foi maior entre os grupos genéticos detectados pelo programa Structure (F ST = 0,070). Essa maior variabilidade indica que não há ameaças à conservação genética da copaíba, em médio prazo

    Tolerance of frugivorous birds to habitat disturbance in a tropical cloud forest

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    In view of the continued decline in tropical forest cover around the globe, forest restoration has become a key tool in tropical rainforest conservation. One of the main - and least expensive - restoration strategies is natural forest regeneration. By aiding forest seed influx both into disturbed and undisturbed habitats, frugivorous birds facilitate forest regeneration. This study focuses on the tolerance of a frugivorous bird community to anthropogenic habitat disturbance within the broader context of natural forest regeneration with conservation purposes. It was carried out in the tropical cloud forest of Costa Rica's Talamanca Mountains. Bird community response and tolerance to habitat disturbance was assessed by comparing bird presence and densities along a disturbance gradient, ranging from open pastures to closed mature forests. Birds were censused along nine transects applying the variable width line transect procedure. Forty relevant frugivorous bird species were observed during 102 h of survey time. Densities were calculated for 33 species; nine species responded negatively to increasing level of disturbance and nine others positively. Results indicate that large frugivores are generally moderately tolerant to intermediate, but intolerant to severe habitat disturbance, and that tolerance is often higher for medium and small frugivores. It appears that moderately disturbed habitats in tropical cloud forests are highly suitable for restoration through natural regeneration aided by frugivorous birds. Due to a lack of large forest seed dispersers, severely disturbed habitats appear less suitabl

    Conservation status in Caribbean coot <i>Fulica caribaea</i> in the Netherlands Antilles and other parts of the Caribbean

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    In 2005 to 2006 we assessed the status of the Caribbean coot Fulica caribaea in the Netherlands Antilles, largely semi-arid islands in the South Caribbean, with small numbers of permanently available fresh water bodies. The Caribbean coot is a freshwater bird which is dependent on the seasonal availability of freshwater ponds for breeding; it breeds on 4 of the 6 islands of the Netherlands Antilles, viz. Curaçao (first recorded in 1956), Bonaire (1974), Aruba (1977), and St. Maarten (1981). Compared to the period up to and including 1979, group sizes in 1980 to 2006 were larger on Curaçao, and it appears more abundant in the latter period on all islands. We report on 49 sites (&gt;5 ha) in the Caribbean where the species has been recorded, or where we would expect it to occur on the basis of available habitat. Threats to the Caribbean coot include drainage or reclamation of habitat, hunting, and pollution. Few sites receive protection. The coot has a restricted range of occupancy of some 1000 km2, spread out over 13 islands, representing 10 countries. Based on its restricted range, coupled with high levels of threat and the limited amount of protection, we recommend that the species be included as 'Vulnerable' in the IUCN (International Union for the Conservation of Nature and Natural Resources, World Conservation Union) Red list. An increase in the level of (legal) protection, in addition to an increase in the amount of habitat included in the regional protected areas network and heightening the awareness of the needs of this Caribbean endemic are overdue. The establishment of permanent freshwater ponds, especially in the arid parts of its range, appears favourable for the species, and may aid conservation.</p
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