917 resultados para Biotic communities--Ontario--Short Hills Provincial Park.


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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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The aim of this work was to assess and compare the diversity of the ichthyofauna in three headwater rivers of Paraíba-do-Sul basin in the Serra do Mar State Park, Núcleo Santa Virgínia. A total of 1,774 specimens of 16 species of fishes belonging to 6 families were caught. Characiforms were the most abundant fish at all three sites, followed by Cyprinodontiformes, Siluriformes, and Perciformes. The Shannon index (H′), evenness (E), and the Jaccard and Morisita-Horn similarity indexes were low, indicating both low diversity and low similarity of species among the three streams. The values of these indexes should be evaluated according to the biotic and abiotic conditions in each environment. It is clear that in mountain streams of the Atlantic Forest, these low values occur because of the presence of a few abundant and many rare species.

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First measurements of dihadron correlations for charged particles are presented for central PbPb collisions at a nucleon-nucleon center-of-mass energy of 2.76TeV over a broad range in relative pseudorapidity (Δν) and the full range of relative azimuthal angle (Δø). The data were collected with the CMS detector, at the LHC. A broadening of the away-side (Δø y≈ π) azimuthal correlation is observed at all Δν, as compared to the measurements in pp collisions. Furthermore, long-range dihadron correlations in Δν are observed for particles with similar ø values. This phenomenon, also known as the \ridge, persists up to at least jΔνj = 4. For particles with transverse momenta (pT) of 2-4 GeV/c, the ridge is found to be most prominent when these particles are correlated with particles of pT = 2-6 GeV/c, and to be much reduced when paired with particles of pT = 10-12 GeV/c. Copyright CERN.

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Fungi constitute an important part of the soil ecosystem, playing key roles in decomposition, cycling processes, and biotic interactions. Molecular methods have been used to assess fungal communities giving a more realistic view of their diversity. For this purpose, total DNA was extracted from bulk soils cultivated with tomato (STC), vegetables (SHC), and native forest (SMS) from three sites of the Taquara Branca river basin in Sumaré County, São Paulo State, Brazil. This metagenomic DNA was used as a template to amplify fungal 18S rDNA sequences, and libraries were constructed in Escherichia coli by cloning PCR products. The plasmid inserts were sequenced and compared to known rDNA sequences in the GenBank database. Of the sequenced clones, 22 were obtained from the SMS sample, 18 from the SHC sample, and 6 from the STC sample. Although most of the clone sequences did not match the sequences present in the database, individual amplified sequences matched with Glomeromycota (SMS), Fungi incertae sedis (SMS), and Neocallimastigomycota (SHC). Most of the sequences from the amplified taxa represent uncultured fungi. The molecular analysis of variance (AMOVA) indicated that fluctuations observed of haplotypes in the composition may be related to herbicide application. © 2013 Silvana Pompéia Val-Moraes et al.

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Introduction There is a renewed call for a new approach to development with emphasis on community empowerment or participation, with the belief that more sustainable activities will be undertaken in those communities. Much of that call, however, is coming not from within the communities, but primarily from advocates of change who may have little to do with those communities. What then will the new approach bring apart from a change in who are the decision-makers? And how do we ensure that the change that is called for will, in fact, bring added benefits to the communities themselves? To be sure, there are some successful stories of a community approach to problem solving. However, there are also many more stories of project failures. Serious analytical work, therefore, needs to be done to determine the factors that promote a successful community-based approach; when this approach should be used; and the methodology that should be employed. In an attempt to determine these factors, a brief analysis will be made of some of the governing structures in the subregion and their possible impact on the proposed new approach. Some of the earlier efforts at stakeholder and community approach to projects will also be examined as well as the new development strategy that is prompting the call for this new paradigm. The new paradigm focuses to a large extent on decision-making and community empowerment. With few exceptions, it is short on the promotion of tangible activities that are based on the resource inventory of the communities. This is not surprising, since, as noted before, the advocates of community empowerment may have very little connection with the communities and, in most cases, are unfamiliar with the resource base. Hence, a theoretical case is made, suggesting more style than substance. Another obvious shortcoming of this new paradigm is its continued over- dependence on assistance from the outside to build communities. Externally funded projects, seminars and meetings outside of the communities and foreign technical assistance continue to dominate these projects. While, of course, all communities have basic common needs such as water, health, education and electricity, there is sufficient diversity within communities to allow for tailoring of activities and programmes such that their differences become assets. It is in that context, that agro-tourism activities, standards, agricultural diversification, food and nutrition and priority setting have been chosen as aspects and activities for promoting community development, drawing on the various strengths of communities, rural or urban.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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

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

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

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

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Grassland ecosystems have been severely reduced and grassland bird populations have experienced consistent declines. National Park Service (NPS) properties on the Great Plains provide breeding habitat for grassland songbirds, though little is known about the quality of this habitat. A short-term study on songbirds at three NPS properties complemented current monitoring, providing an among park comparison addressing grassland bird productivity and fidelity relative to NPS property size. During 2008-2009, I assessed avian species richness, and estimated bird density and grassland songbird nest success. Bird species richness was greatest at small and medium sites, while number of nesting obligate species was greatest at the large site. Species-specific densities varied among sites, with few grassland obligates occurring at all three sites. Nest success estimates for grassland obligates were highest at the small site and lower at the large site. Another method to quantify habitat quality is assessment of breeding site fidelity. Current extrinsic markers used in monitoring site fidelity are inadequate for small birds; stable isotope analyses provide an alternative. I compared two techniques for assigning stable isotope tissue origin and measured grassland songbird site fidelity. My method of assigning origin provided site-specific variances of expected stable isotope values, an improvement over the most commonly used method. Fidelity tended to be higher at the large site, which may indicate a more robust breeding community of grassland birds. The small size of two of my sites precluded large sample sizes and made strong inferences difficult. To quantify how scientists cope with weak inference, I conducted a literature review. Strong inference was rarely observed, and most authors of weak-inference papers provided specific management recommendations. I suggest that adaptive management is an ideal method to resolve uncertainty from weak inference. Managers should consider my results within the context of regional and global management and the extent to which their unit might aide songbird conservation.