39 research outputs found

    Biogeography of Amazonian fishes: deconstructing river basins as biogeographic units

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    Tree diversity and above-ground biomass in the South America Cerrado biome and their conservation implications

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    Less than half of the original two million square kilometers of the Cerrado vegetation remains standing, and there are still many uncertainties as to how to conserve and prioritize remaining areas effectively. A key limitation is the continuing lack of geographically-extensive evaluation of ecosystem-level properties across the biome. Here we sought to address this gap by comparing the woody vegetation of the typical cerrado of the Cerrado–Amazonia Transition with that of the core area of the Cerrado in terms of both tree diversity and vegetation biomass. We used 21 one-hectare plots in the transition and 18 in the core to compare key structural parameters (tree height, basal area, and above-ground biomass), and diversity metrics between the regions. We also evaluated the effects of temperature and precipitation on biomass, as well as explored the species diversity versus biomass relationship. We found, for the first time, both that the typical cerrado at the transition holds substantially more biomass than at the core, and that higher temperature and greater precipitation can explain this difference. By contrast, plot-level alpha diversity was almost identical in the two regions. Finally, contrary to some theoretical expectations, we found no positive relationship between species diversity and biomass for the Cerrado woody vegetation. This has implications for the development of effective conservation measures, given that areas with high biomass and importance for the compensation of greenhouse gas emissions are often not those with the greatest diversity

    Large-scale wind disturbances promote tree diversity in a Central Amazon forest

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    Canopy gaps created by wind-throw events, or blowdowns, create a complex mosaic of forest patches varying in disturbance intensity and recovery in the Central Amazon. Using field and remote sensing data, we investigated the short-term (four-year) effects of large (>2000 m2) blowdown gaps created during a single storm event in January 2005 near Manaus, Brazil, to study (i) how forest structure and composition vary with disturbance gradients and (ii) whether tree diversity is promoted by niche differentiation related to wind-throw events at the landscape scale. In the forest area affected by the blowdown, tree mortality ranged from 0 to 70%, and was highest on plateaus and slopes. Less impacted areas in the region affected by the blowdown had overlapping characteristics with a nearby unaffected forest in tree density (583±46 trees ha-1) (mean±99% Confidence Interval) and basal area (26.7±2.4 m2 ha-1). Highly impacted areas had tree density and basal area as low as 120 trees ha-1 and 14.9 m2 ha-1, respectively. In general, these structural measures correlated negatively with an index of tree mortality intensity derived from satellite imagery. Four years after the blowdown event, differences in size-distribution, fraction of resprouters, floristic composition and species diversity still correlated with disturbance measures such as tree mortality and gap size. Our results suggest that the gradients of wind disturbance intensity encompassed in large blowdown gaps (>2000 m2) promote tree diversity. Specialists for particular disturbance intensities existed along the entire gradient. The existence of species or genera taking an intermediate position between undisturbed and gap specialists led to a peak of rarefied richness and diversity at intermediate disturbance levels. A diverse set of species differing widely in requirements and recruitment strategies forms the initial post-disturbance cohort, thus lending a high resilience towards wind disturbances at the community level. © 2014 Marra et al

    Consórcios Intermunicipais de Saúde: o caso do Paraná, Brasil Inter-municipal health consortia: the case of Paraná State, Brazil

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    Os Consórcios Intermunicipais de Saúde (CIS) surgiram no âmbito do SUS no final da década de 80. Os gestores municipais aderiram a essa estratégia, visando potencializar as ações e serviços de saúde oferecidos à população. Esta pesquisa analisou o perfil dos CIS do Paraná, Brasil, focalizando a assistência médica especializada. Os dados são dos relatórios sobre os consórcios realizados pelo Conselho Estadual de Saúde e dos questionários enviados para os vinte CIS. Os parâmetros utilizados foram a Portaria nº 1.101 e dados publicados do perfil do sistema de saúde do Paraná em 2000. Dos 399 municípios paranaenses, 81,5% integram CIS. Os especialistas são cedidos pelos municípios (4,4%), Estado (13,6%), união (12,8%), ou contratados pelo próprio CIS (69,2%). A oferta de consultas especializadas não é suficiente ou sua distribuição é feita de forma inadequada. Há falha no mecanismo de referência e contra-referência. O CIS é um instrumento viável para ampliar e potencializar a capacidade dos municípios em ofertar consultas especializadas; porém, há necessidade de ser utilizado com critérios, planejamento e adequado sistema de referência e contra-referência.<br>Inter-municipal health consortia emerged in Brazil's Unified National Health System (SUS) policy in the late 1980s. Municipal health administrators adhered to this strategy with the aim of upgrading health services supplied to the population. This research analyzes the profile of such consortia in Paraná State, focusing on specialized medical care. Data were obtained from reports by the State Health Council and questionnaires sent to all 20 existing municipal health consortia. Governmental Decree no. 1,101 and data published in 2000 on the profile of the health system in Paraná were used as references. Of the 399 municipalities in Paraná State, 81.5% have joined municipal consortia. Specialists are allocated by municipalities (4.4%), the State government (13.6%), or Federal Government (12.8%); another 69.2% are hired by the consortia themselves. The supply of consultations with specialists is either insufficient or inadequately distributed, and there are flaws in the referral and counter-referral system. Municipal health consortia serve as viable instrument for expanding and increasing the capacity of municipalities to supply specialized care, although there is a need for well-defined criteria, planning, and improving of the referral and counter-referral system
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