1,185 research outputs found

    Consequências ambientais da expansão da palma de óleo no nordeste do Pará e implicações para políticas públicas

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    A trajetória recente da expansão da dendeicultura na Amazônia está fortemente associada às políticas públicas, com dinâmicas de ações complexas, que atuam em escalas globais e regionais, sendo crucial compreender as consequências ambientais desse cultivo na região. A expansão do plantio do dendezeiro (ou palma de óleo) vem ocorrendo gradativamente. Em 2008, tais cultivos ocupavam 1,4% da área do polo do dendê no Pará e, em 2016, a área “degradada” usada para esse plantio já somava cerca de 279 mil hectares, ou seja, 4,7% na área do referido polo. O cenário de expansão do dendezeiro com governança ambiental para 2025 estima o acréscimo de, aproximadamente, 2 mil km² de novas áreas no Pará. Nossos estudos mostraram que os plantios de dendezeiro são de alto impacto para a biodiversidade arbórea e de aves, e não oferecem habitat para as espécies da floresta primária, incluindo algumas raras e de interesse para a conservação. Por outro lado, os remanescentes florestais de propriedades privadas exercem importante papel na retenção de espécies florestais em paisagens dominadas por palma de óleo. Recomenda-se que haja a definição e o mapeamento de áreas degradadas nas políticas de estímulo à dendeicultura; que os programas se integrem a políticas públicas com prioridade à restauração ecológica e à formação de corredores ecológicos em paisagens antropizadas do Estado; bem como que haja o acompanhamento e o monitoramento socioambiental da dendeicultura na Amazônia

    A roadmap to identifying and filling shortfalls in Neotropical ornithology

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    Abstract Securing the long-term resilience of the world’s most speciose avifauna, that of the Neotropics, requires spatially and temporally explicit data to inform decisions. We examine gaps in our knowledge of the region’s avifauna through the lens of the biodiversity shortfall concept: the gaps between realized knowledge and complete knowledge. This framework serves as a useful tool to take stock of the last 25 yr of Neotropical ornithological work since the untimely death of Ted Parker. Here, we highlight 7 key shortfalls: taxonomy, distribution, abundance, evolutionary patterns, abiotic tolerances, species traits, and biotic interactions. We then propose an eighth—and new—“Parkerian” shortfall that reflects a lack of basic natural history knowledge key to understanding how species might respond to environmental challenges. Bridging this shortfall will help reverse declines by informing reintroduction, recovery network, and habitat restoration efforts. We discuss the challenges imposed by each shortfall and how strategies such as citizen-science initiatives and technological advances can either remedy or mitigate the uncertainty they generate

    Status of the globally threatened forest birds of northeast Brazil

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    The Atlantic Forest of northeast Brazil hosts a unique biota which is among the most threatened in the Neotropics. Near-total conversion of forest habitat to sugar cane monocultures has left the region's endemic forest-dependent avifauna marooned in a few highly-fragmented and degraded forest remnants. Here we summarise the current status of 16 globally threatened species based on surveys conducted over the last 11 years. We found a bleak situation for most of these species and consider that three endemics: Glaucidium mooreorum (Pernambuco Pygmy-owl), Cichlocolaptes mazarbarnetti (Cryptic Treehunter) and Philydor novaesi (Alagoas Foliage-gleaner) are most likely globally extinct. Some positive news can, however, be reported for both Leptodon forbesi (White-collared Kite) and Synallaxis infuscata (Pinto's Spinetail) which may warrant re-evaluation of their respective red list statuses. We outline a road map to prioritise conservation interventions in the region directed at preventing the extinction of this suite of threatened bird species and their companion biota.A Floresta Atlântica do Nordeste do Brasil abriga uma biota única que está entre as mais ameaçadas na região Neotropical. A quase total conversão dos habitats florestais em áreas de plantação de cana-de-açúcar deixou a avifauna florestal endêmica da região isolada em poucos remanescentes florestais altamente fragmentados e degradados. Aqui, resumimos o status atual de 16 espécies globalmente ameaçadas baseado em pesquisas conduzidas nos últimos 11 anos. Encontramos uma situação desanimadora para a maioria dessas espécies e consideramos que três espécies endêmicas: Glaucidium mooreorum (caburé-de-pernambuco), Cichlocolaptes mazarbarnetti (gritador-do-nordeste) e Philydor novaesi (limpa-folha-do-nordeste) estejam provavelmente extintas. Algumas notícias positivas podem, no entanto, ser reportadas para Leptodon forbesi (gavião-de-pescoço-branco) e Synallaxis infuscata (tatac), do qual necessitam de uma reavaliação de seus respectivos status na lista vermelha. Descrevemos em linhas gerais um planejamento para priorizar as intervenções conservacionistas na região direcionadas na prevenção da extinção do conjunto das espécies de aves ameaçadas e sua biota associada

    Study of B0(s)→K0Sh+h′− decays with first observation of B0s→K0SK±π∓ and B0s→K0Sπ+π−

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    A search for charmless three-body decays of B 0 and B0s mesons with a K0S meson in the final state is performed using the pp collision data, corresponding to an integrated luminosity of 1.0 fb−1, collected at a centre-of-mass energy of 7 TeV recorded by the LHCb experiment. Branching fractions of the B0(s)→K0Sh+h′− decay modes (h (′) = π, K), relative to the well measured B0→K0Sπ+π− decay, are obtained. First observation of the decay modes B0s→K0SK±π∓ and B0s→K0Sπ+π− and confirmation of the decay B0→K0SK±π∓ are reported. The following relative branching fraction measurements or limits are obtained B(B0→K0SK±π∓)B(B0→K0Sπ+π−)=0.128±0.017(stat.)±0.009(syst.), B(B0→K0SK+K−)B(B0→K0Sπ+π−)=0.385±0.031(stat.)±0.023(syst.), B(B0s→K0Sπ+π−)B(B0→K0Sπ+π−)=0.29±0.06(stat.)±0.03(syst.)±0.02(fs/fd), B(B0s→K0SK±π∓)B(B0→K0Sπ+π−)=1.48±0.12(stat.)±0.08(syst.)±0.12(fs/fd)B(B0s→K0SK+K−)B(B0→K0Sπ+π−)∈[0.004;0.068]at90%CL

    Measurement of the CP-violating phase \phi s in Bs->J/\psi\pi+\pi- decays

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    Measurement of the mixing-induced CP-violating phase phi_s in Bs decays is of prime importance in probing new physics. Here 7421 +/- 105 signal events from the dominantly CP-odd final state J/\psi pi+ pi- are selected in 1/fb of pp collision data collected at sqrt{s} = 7 TeV with the LHCb detector. A time-dependent fit to the data yields a value of phi_s=-0.019^{+0.173+0.004}_{-0.174-0.003} rad, consistent with the Standard Model expectation. No evidence of direct CP violation is found.Comment: 15 pages, 10 figures; minor revisions on May 23, 201

    Differential branching fraction and angular analysis of the decay B0→K∗0μ+μ−

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    The angular distribution and differential branching fraction of the decay B 0→ K ∗0 μ + μ − are studied using a data sample, collected by the LHCb experiment in pp collisions at s√=7 TeV, corresponding to an integrated luminosity of 1.0 fb−1. Several angular observables are measured in bins of the dimuon invariant mass squared, q 2. A first measurement of the zero-crossing point of the forward-backward asymmetry of the dimuon system is also presented. The zero-crossing point is measured to be q20=4.9±0.9GeV2/c4 , where the uncertainty is the sum of statistical and systematic uncertainties. The results are consistent with the Standard Model predictions

    Opposite-side flavour tagging of B mesons at the LHCb experiment

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    The calibration and performance of the oppositeside flavour tagging algorithms used for the measurements of time-dependent asymmetries at the LHCb experiment are described. The algorithms have been developed using simulated events and optimized and calibrated with B + →J/ψK +, B0 →J/ψK ∗0 and B0 →D ∗− μ + νμ decay modes with 0.37 fb−1 of data collected in pp collisions at √ s = 7 TeV during the 2011 physics run. The oppositeside tagging power is determined in the B + → J/ψK + channel to be (2.10 ± 0.08 ± 0.24) %, where the first uncertainty is statistical and the second is systematic

    Search for CP violation in D+→ϕπ+ and D+s→K0Sπ+ decays

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    A search for CP violation in D + → ϕπ + decays is performed using data collected in 2011 by the LHCb experiment corresponding to an integrated luminosity of 1.0 fb−1 at a centre of mass energy of 7 TeV. The CP -violating asymmetry is measured to be (−0.04 ± 0.14 ± 0.14)% for candidates with K − K + mass within 20 MeV/c 2 of the ϕ meson mass. A search for a CP -violating asymmetry that varies across the ϕ mass region of the D + → K − K + π + Dalitz plot is also performed, and no evidence for CP violation is found. In addition, the CP asymmetry in the D+s→K0Sπ+ decay is measured to be (0.61 ± 0.83 ± 0.14)%
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