5 research outputs found

    Evolution of seed dispersal in the Cerrado biome : ecological and phylogenetic considerations

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    The investigation of the phylogeny of a group of organisms has the potential to identify ecological and evolutionary processes that have been occurring within a community. Seed dispersal is a key process in the life cycle of vegetation and reflects different reproductive strategies of plants to a set of ecological and evolutionary factors. Knowing the dispersal syndromes and fruits types of a plant community may help elucidate plant-animal interactions and colonization strategies of plants. We investigated dispersal syndromes and fruit types in Cerrado formations as a parameter for understanding the evolution of angiosperm reproductive strategies in this mega-diverse tropical biome. To do this we identified and mapped the distribution of different parameters associated with seed dispersal on a phylogeny of Cerrado angiosperms genera and tested the presence of phylogenetic signal. The results showed that there were strong relationships between fruit types, seed dispersal strategies and vegetation life forms and that these traits were closely related to angiosperms phylogeny and, together, contribute to the evolution of plants in the forest, savanna and grassland formations of the Cerrado biome

    Efeitos ambientais da disposição oceânica de esgotos por meio de emissários submarinos: Uma revisão

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    Oceanic disposal systems of domestic sewage, or submarine sewage outfalls, have been historically used around the world as a solution for urban effluents, in special due to economic aspects. However, release into the ocean, in shallow or deep waters, may induce a set of negative environmental impacts, as eutrophication, toxic algal blooms, pathogenic microorganisms introduction and contamination by chemical substances which are capable of causing toxic effects to the biota and bioaccumulation. Thus, the release of untreated sewage into the sea does not constitute an adequate environmental practice; then, urban effluents should be treated in order to remove nutrients, contaminants and pathogenic organisms and avoid environmental degradation

    Using rapid assessment of marine pollution (RAMP) techniques to assess the quality of marine sediments

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    Sediments represent an important environmental compartment, because they provide substrate for a range of species and may accumulate contaminants in high concentrations. However, the universe of methods to assess the quality of sediments is still small. This investigation aimed to assess the quality of sediments from some sites of Ubatuba (SE Brazil). To achieve that, sediments were analyzed for the presence of PAHs, by immunoassay ELISA kit for the carcinogenic PAH (c-PAH) RaPID Assay, and for toxicity to amphipods, sea-urchin embryos and direct exposure of mussel hemocytes and measurements of the nuetral red retention time (NRTT). Results showed higher levels of PAHs in sediments from Itagua and Ribeira, those more intensely affected by contamination sources. The ecotoxicological analyses indicated these two sites as more degraded, together with the sediments from Lamberto Beach, which is also influenced by nautical activities. The NRRT correlated with the quantities of PAHs in sediments. We concluded that Ribeira Bay and Itaguá Beach need more detailed investigation on pollution and that the NRRT assay exposing directly hemocytes to sediment elutriates can be a useful tool to assessing sediment quality
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