60 resultados para Biodiversity conservation - Victoria

em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo


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Serra da Canastra National Park (SCNP) is one of the most important protected areas in the Cerrado biome. Despite its importance to the conservation of rare and endangered species like Brazilian Merganser, two bills were approved in 2010 by Brazil's Chamber of Deputies aiming to reduce SCNP's official boundaries and to transform some of its parts into an Environmental Protection Area (EPA). We evaluated whether such changes would facilitate mining areas to be legally exploited within the park's area, and if those mining areas would represent a threat to Brazilian Merganser populations at SCNP. Results showed that 55% of the mining areas currently within the National Park will be located within the new EPA, and six hydrographic micro-basins inhabited by Brazilian Merganser could be affected by environmental impacts caused by mineral exploitation in those areas. For these reasons, we recommend the two bills be refused at the Federal Senate.

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Almost two-thirds of the Brazilian territory still has prevalence of natural vegetation. Although not all pristine, much of these areas have high conservation value. 170 million hectare (Mha) of the natural vegetation is located within Federal and State protected areas. Most of the remaining 367 Mha is on private agriculture lands, where the Forest Act is the most important legal framework for conservation. In July 2010, the Brazilian parliament began the analysis of a substitutive legislation for the Forest Act. The main motivations for the revision is that, on the one hand, it has been found ineffective in protecting natural vegetation, and on the other hand, it is perceived as a barrier against development in the agriculture sector. The substitutive Forest Act, as it presently stands, does not represent a balance between existing standpoints and objectives; it may drive development towards either more private protection through market-driven compensation actions, or increased deforestation and less nature protection/restoration. This article uses outcomes from modeling analyses to discuss weaknesses of the substitutive Forest Act and to suggest possible improvements. (C) 2011 Elsevier Ltd. All rights reserved.

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The time is ripe for a comprehensive mission to explore and document Earth's species. This calls for a campaign to educate and inspire the next generation of professional and citizen species explorers, investments in cyber-infrastructure and collections to meet the unique needs of the producers and consumers of taxonomic information, and the formation and coordination of a multi-institutional, international, transdisciplinary community of researchers, scholars and engineers with the shared objective of creating a comprehensive inventory of species and detailed map of the biosphere. We conclude that an ambitious goal to describe 10 million species in less than 50 years is attainable based on the strength of 250 years of progress, worldwide collections, existing experts, technological innovation and collaborative teamwork. Existing digitization projects are overcoming obstacles of the past, facilitating collaboration and mobilizing literature, data, images and specimens through cyber technologies. Charting the biosphere is enormously complex, yet necessary expertise can be found through partnerships with engineers, information scientists, sociologists, ecologists, climate scientists, conservation biologists, industrial project managers and taxon specialists, from agrostologists to zoophytologists. Benefits to society of the proposed mission would be profound, immediate and enduring, from detection of early responses of flora and fauna to climate change to opening access to evolutionary designs for solutions to countless practical problems. The impacts on the biodiversity, environmental and evolutionary sciences would be transformative, from ecosystem models calibrated in detail to comprehensive understanding of the origin and evolution of life over its 3.8 billion year history. The resultant cyber-enabled taxonomy, or cybertaxonomy, would open access to biodiversity data to developing nations, assure access to reliable data about species, and change how scientists and citizens alike access, use and think about biological diversity information.

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Species distribution models (SDMs) can be useful for different conservation purposes. We discuss the importance of fitting spatial scale and using current records and relevant predictors aiming conservation. We choose jaguar (Panthera onca) as a target species and Brazil and Atlantic Forest biome as study areas. We tested two different extents (continent and biome) and resolutions (similar to 4 Km and similar to 1 Km) in Maxent with 186 records and 11 predictors (bioclimatic, elevation, land-use and landscape structure). All models presented satisfactory AUC values (>0.70) and low omission errors (<23%). SDMs were scale-sensitive as the use of reduced extent implied in significant gains to model performance generating more constrained and real predictive distribution maps. Continental-scale models performed poorly in predicting potential current jaguar distribution, but they reached the historic distribution. Specificity increased significantly from coarse to finer-scale models due to the reduction of overprediction. The variability of environmental space (E-space) differed for most of climatic variables between continental and biome-scale and the representation of the E-space by predictors differed significantly (t = 2.42, g.I. = 9, P < 0.05). Refining spatial scale, incorporating landscape variables and improving the quality of biological data are essential for improving model prediction for conservation purposes.

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Receiving coastal waters and estuaries are among the most nutrient-enriched environments on earth, and one of the symptoms of the resulting eutrophication is the proliferation of opportunistic, fast-growing marine seaweeds. Here, we used a widespread macroalga often involved in blooms, Ulva spp., to investigate how supply of nitrogen (N) and phosphorus (P), the two main potential growth-limiting nutrients, influence macroalgal growth in temperate and tropical coastal waters ranging from low- to high-nutrient supplies. We carried out N and P enrichment field experiments on Ulva spp. in seven coastal systems, with one of these systems represented by three different subestuaries, for a total of nine sites. We showed that rate of growth of Ulva spp. was directly correlated to annual dissolved inorganic nitrogen (DIN) concentrations, where growth increased with increasing DIN concentration. Internal N pools of macroalgal fronds were also linked to increased DIN supply, and algal growth rates were tightly coupled to these internal N pools. The increases in DIN appeared to be related to greater inputs of wastewater to these coastal waters as indicated by high delta 15N signatures of the algae as DIN increased. N and P enrichment experiments showed that rate of macroalgal growth was controlled by supply of DIN where ambient DIN concentrations were low, and by P where DIN concentrations were higher, regardless of latitude or geographic setting. These results suggest that understanding the basis for macroalgal blooms, and management of these harmful phenomena, will require information as to nutrient sources, and actions to reduce supply of N and P in coastal waters concerned.

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The spatial and temporal variation of microphytobenthic biomass in the nearshore zone of Martel Inlet (King George Island, Antarctica) was estimated at several sites and depths (10-60 m), during three summer periods (1996/1997, 1997/1998, 2004/2005). The mean values were inversely related to the bathymetric gradient: higher ones at 10-20 m depth (136.2 +/- A 112.5 mg Chl a m(-2), 261.7 +/- A 455.9 mg Phaeo m(-2)), intermediate at 20-30 m (55.6 +/- A 39.5 mg Chl a m(-2), 108.8 +/- A 73.0 mg Phaeo m(-2)) and lower ones at 40-60 m (22.7 +/- A 23.7 mg Chl a m(-2), 58.3 +/- A 38.9 mg Phaeo m(-2)). There was also a reduction in the Chl a/Phaeo ratio with depth, from 3.2 +/- A 3.2 (10-20 m) to 0.7 +/- A 1.0 (40-60 m), showing a higher contribution of senescent phytoplankton and/or macroalgae debris at the deeper sites and the limited light flux reaching the bottom. Horizontal differences found in the biomass throughout the inlet could not be clearly related to hydrodynamics or proximity to glaciers, but with sediment characteristics. An inter-summer variation was observed: the first summer presented the highest microphytobenthic biomass apparently related to more hydrodynamic conditions, which causes the deposition of allochthonous material.

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The photo-induced toxicity of anthracene was investigated as the mortality in Antarctic shallow water amphipod, Gondogeneia antarctica, at different concentrations of anthracene and different periods of exposure to natural sunlight and artificial UVA and UVB radiations. When exposed to natural sunlight, animals contaminated in the dark and placed in clean water or in anthracene solutions showed different degrees of mortality, dose-time dependent. Effects were even more evident when these animals were exposed to artificial UVA or UVB radiations. Depuration seemed to be a slow process. The effects of UV radiation and anthracene alone and the effects of the interactions of these two stressors implied that solar radiation is an important parameter that deserves consideration in the environmental assessment of polycyclic aromatic hydrocarbons in Antarctic coastal waters. G. antarctica proved to be a good bioindicator for the phototoxicity of anthracene in Antarctic shallow waters.

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The genus Cnodalomyia includes only two Brazilian species: C. obtusa Hull, 1962 and C. catarinensis Lamas and Mellinger, 2008. Studying material deposited in the Museu de Zoologia da Universidade de Sao Paulo (MZUSP), the authors found a long series of unidentified specimens of the genus, some of which are specimens of C. obtusa labelled with the same data as the type series as well as other specimens from different localities, representing an enlargement of the known geographic records of the species. This material, together with the types of C. catarinensis, enables this revision. A redescription of the genus and of its type species, C. obtusa, including descriptions and illustrations of its spermathecae and egg, until now never described, the description and illustration of two new species (C. artigasi sp. nov. and C. papaveroi sp. nov.), the diagnosis and egg description of C. catarinensis and an identification key to all included species are presented herein.

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The gross morphology of the gas bladder is described, illustrated, compared and categorized among 86 of 88 nominal valid and six undescribed species representing all 31 genera of Doradidae with comments on ontogenetic and taxonomic variation when observed. The putatively basal-most doradids exhibit an unmodified cordiform gas bladder. Derived taxa exhibit an impressive suite of modifications including the addition of a secondary bladder, pronounced reduction of the posterolateral chambers, internal trabeculae, associations with bony capsule-like expansions of the anterior (Weberian) vertebrae, and accessory diverticula varying widely in size, shape, abundance, and distribution. Intra-specific differences are minor, most often reflective of ontogenetic changes especially in large-size species, whereas inter-specific and inter-generic differences are significant, in many cases diagnostic, and suggestive of phylogenetic signal excepting instances of evident convergence such as gas bladder reduction in Rhynchodoras and all but one species of Leptodoras.

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Extant Doras are newly diagnosed among Doradidae by the unique combination of maxillary barbels long and fimbriate; mesethmoid with anterior lateral margins converging towards narrow tip; single anterior cranial fontanel contained largely within frontals and anteriorly by mesethmoid (posterior cranial fontanel occluded); anterior nuchal plate wide, pentaganol or roughly hexagonal, sharing distinct lateral suture with epioccipital and isolating supraoccipital from middle nuchal plate; nuchal foramina absent; coracoid process short, posterior tip falling well short of that of postcleithral process; dentary with acicular teeth; and skin immediately ventral to postcleithral process perforated with conspicuous pores. One fossil species, dagger D. dioneae, and two nominal extant species, D. carinatus and D. micropoeus, are recognized as valid and the latter two redescribed. Three additional extant species, D. phlyzakion, D. higuchii and D. zuanoni, are newly described from the middle Amazon and tributaries, lower Amazon tributaries and rio Araguaia (Tocantins drainage), respectively. Doras phlyzakion and D. zuanoni form a monophyletic group that is found in lowland, lentic habitats, and is characterized by multiple conspicuous pores in skin on breast and abdomen, a trait unique among doradids and rare if not unique among all catfishes. The remaining extant species, D. carinatus, D. higuchii and D. micropoeus, with uncertain relationships, are found in upland, lotic habitats. The occurrence of D. carinatus in the Orinoco basin suggests a historical link between right-bank tributaries of the lower Orinoco (e.g., Caroni) draining the western Guiana Shield and more eastern rivers (e.g., Cuyuni-Essequibo) that drain the Shield directly into the Atlantic Ocean. A key to extant species is provided, a neotype is designated for Silurtis carinatus Linnaeus 1766, and Mormyropsis Miranda Ribeiro, 1911, is placed in the synonymy of Doras Lacepede, 1803.

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The Castniidae, or butterfly moths, are characteristically colourful diurnal moths, distributed throughout the tropics except in Africa. The Neotropical representatives forage almost exclusively on monocotyledonous plants and many species are crop pests with more than 60% of the Neotropical castniids found or endemic in Brazil. Research studies that focus on taxonomy, systematics, and morphology of this group are scarce. In this study, Yagra Oiticica, a small genus restricted to south-eastern South America, is revised and the diagnostic morphological characters of male and female genitalia are illustrated. This research is part of long-term study on the Castniidae for future phylogenetic analysis.

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We analysed the seasonal distribution of the zooplankton community in an anthropogenically impacted area (Paranagua Bay) and a non-impacted area (Laranjeiras Bay) of the Paranagua Bay Estuarine Complex. Large phytoplankton (>50 mu m) and zooplankton were collected every two months, between August 2003 and June 2004. The phytoplankton community was numerically dominated by diatoms (78%) and dinoflagellates (19%). Zooplankton abundance varied between 670 and 100,716 individuals m(-3), with a dominance of copepods, mainly the calanoids Acartia lilljeborgii, Acartia tonsa and Pseudodiaptomus acutus. A clear seasonal pattern was observed: copepods were significantly more abundant during the rainy than in the dry season. Significant differences in abundance between the two bays were detected only for cirripede larvae, which were more abundant in Paranagua Bay. This lack of difference between the two areas was probably a consequence of the water circulation along the estuary, which may have diluted and dispersed the pollutants from Paranagua Bay to other areas of the estuary.

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The aim of this work is to use GIS integration data to characterize sedimentary processes in a SubTropical lagoon environment. The study area was the Canan,ia Inlet estuary in the southeastern section of the Canan,ia Lagoon Estuarine System (CLES), state of So Paulo, Brazil (25A degrees 03'S/47A degrees 53'W). The area is formed by the confluence of two estuarine channels forming a bay-shaped water body locally called "Trapand, Bay". The region is surrounded by one of the most preserved tracts of Atlantic Rain Forest in Southwestern Brazil and presents well-developed mangroves and marshes. In this study a methodology was developed using integrated a GIS database based on bottom sediment parameters, geomorphological data, remote sensing images, Hidrodynamical Modeling data and geophysical parameters. The sediment grain size parameters and the bottom morphology of the lagoon were also used to develop models of net sediment transport pathways. It was possible to observe that the sediment transport vectors based on the grain size model had a good correlation with the transport model based on the bottom topography features and Hydrodynamic model, especially in areas with stronger energetic conditions, with a minor contribution of finer sediments. This relation is somewhat less evident near shallower banks and depositional features. In these regions the organic matter contents in the sediments was a good complementary tool for inferring the hydrodynamic and depositional conditions (i.e. primary productivity, sedimentation rates, sources, oxi-reduction rates).

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The nests of Myrmelachista are found in tree trunk cavities and branches. The biology of these arboreal ants is still relatively unknown. We investigated the nesting behaviour of this genus in fallen dry twigs in the Atlantic rainforest of southeastern Brazil. Physical characteristics of the nests, colony demographics, presence of breeders and ant worker sizes were recorded. Samples were collected weekly for 12 months, along open, sunny and undisturbed trails within forest remnants. In all, 202 nests were collected and six species were recorded. Myrmelachista ruszkii had the highest population of immatures and the greatest number of nests found. Myrmelachista nodigera had the smallest workers, was the least populous and the colony was housed in the finest branches. These results expand the current knowledge about the diversity and biology of Myrmelachista in the Brazilian Atlantic forest, and describe polydomic nests and competitive behaviour of M. ruszkii.