Pollen, plant macrofossil and charcoal records for palaeovegetation reconstruction in the Mediterranean-Black Sea Corridor since the Last Glacial Maximum

New reconstructions of changing vegetation patterns in the Mediterranean-Black Sea Corridor since the Last Glacial Maximum are being produced by an improved biomisation scheme that uses both pollen and plant macrofossil data, in conjunction. Changes in fire regimes over the same interval will also be reconstructed using both microscopic and macroscopic charcoal remains. These reconstructions will allow a diagnosis of the interactions between climate, fire and vegetation on millennial timescales, and will also help to clarify the role of coastline and other geomorphic changes, salinity and impacts of human activities in this region. These new data sets are being produced as a result of collaboration between the Palynology Working Group (WG-2) within the IGCP-521 project and the international Palaeovegetation Mapping Project (BIOME 6000). The main objective of this paper is to present the goals of this cooperation, methodology, including limitations and planned improvements, and to show the initial results of some applications.

Hydrology and climatology at Laguna La Gaiba, lowland Bolivia: complex responses to climatic forcings over the last 25,000 years

Diatom, geochemical and isotopic data provide a record of environmental change in Laguna La Gaiba, lowland Bolivia (17°450S, 57°350W), over the last ca. 25 000 years. High-resolution diatom analysis around the Last Glacial–Interglacial Transition provides new insights into this period of change. The full and late glacial lake was generally quite shallow, but with evidence of periodic flooding. At about 13 100 cal a BP, just before the start of the Younger Dryas chronozone, the diatoms indicate shallower water conditions, but there is a marked change at about 12 200 cal a BP indicating the onset of a period of high variability, with rising water levels punctuated by periodic drying. From ca. 11 800 to 10 000 cal a BP, stable, deeper water conditions persisted. There is evidence for drying in the early to middle Holocene, but not as pronounced as that reported from elsewhere in the southern hemisphere tropics of South America. This was followed by the onset of wetter conditions in the late Holocene consistent with insolation forcing. Conditions very similar to present were established about 2100 cal a BP. A complex response to both insolation forcing and millennial-scale events originating in the North Atlantic is noted.

Mean climate and variability of the atmosphere and ocean on an aquaplanet

Numerical experiments are described that pertain to the climate of a coupled atmosphere–ocean–ice system in the absence of land, driven by modern-day orbital and CO2 forcing. Millennial time-scale simulations yield a mean state in which ice caps reach down to 55° of latitude and both the atmosphere and ocean comprise eastward- and westward-flowing zonal jets, whose structure is set by their respective baroclinic instabilities. Despite the zonality of the ocean, it is remarkably efficient at transporting heat meridionally through the agency of Ekman transport and eddy-driven subduction. Indeed the partition of heat transport between the atmosphere and ocean is much the same as the present climate, with the ocean dominating in the Tropics and the atmosphere in the mid–high latitudes. Variability of the system is dominated by the coupling of annular modes in the atmosphere and ocean. Stochastic variability inherent to the atmospheric jets drives variability in the ocean. Zonal flows in the ocean exhibit decadal variability, which, remarkably, feeds back to the atmosphere, coloring the spectrum of annular variability. A simple stochastic model can capture the essence of the process. Finally, it is briefly reviewed how the aquaplanet can provide information about the processes that set the partition of heat transport and the climate of Earth.

What do cosmogenic isotopes tell us about past solar forcing of climate?

In paleoclimate studies, cosmogenic isotopes are frequently used as proxy indicators of past variations in solar irradiance on centennial and millennial timescales. These isotopes are spallation products of galactic cosmic rays (GCRs) impacting Earth’s atmosphere, which are deposited and stored in terrestrial reservoirs such as ice sheets, ocean sediments and tree trunks. On timescales shorter than the variations in the geomagnetic field, they are modulated by the heliosphere and thus they are, strictly speaking, an index of heliospheric variability rather than one of solar variability. Strong evidence of climate variations associated with the production (as opposed to the deposition) of these isotopes is emerging. This raises a vital question: do cosmic rays have a direct influence on climate or are they a good proxy indicator for another factor that does (such as the total or spectral solar irradiance)? The former possibility raises further questions about the possible growth of air ions generated by cosmic rays into cloud condensation nuclei and/or the modulation of the global thunderstorm electric circuit. The latter possibility requires new understanding about the required relationship between the heliospheric magnetic fields that scatter cosmic rays and the photospheric magnetic fields which modulate solar irradiance.

Climate variability and human impact in South America during the last 2000 years: synthesis and perspectives from pollen records

An improved understanding of present-day climate variability and change relies on high-quality data sets from the past 2 millennia. Global efforts to model regional climate modes are in the process of being validated against, and integrated with, records of past vegetation change. For South America, however, the full potential of vegetation records for evaluating and improving climate models has hitherto not been sufficiently acknowledged due to an absence of information on the spatial and temporal coverage of study sites. This paper therefore serves as a guide to high-quality pollen records that capture environmental variability during the last 2 millennia. We identify 60 vegetation (pollen) records from across South America which satisfy geochronological requirements set out for climate modelling, and we discuss their sensitivity to the spatial signature of climate modes throughout the continent. Diverse patterns of vegetation response to climate change are observed, with more similar patterns of change in the lowlands and varying intensity and direction of responses in the highlands. Pollen records display local-scale responses to climate modes; thus, it is necessary to understand how vegetation–climate interactions might diverge under variable settings. We provide a qualitative translation from pollen metrics to climate variables. Additionally, pollen is an excellent indicator of human impact through time. We discuss evidence for human land use in pollen records and provide an overview considered useful for archaeological hypothesis testing and important in distinguishing natural from anthropogenically driven vegetation change. We stress the need for the palynological community to be more familiar with climate variability patterns to correctly attribute the potential causes of observed vegetation dynamics. This manuscript forms part of the wider LOng-Term multi-proxy climate REconstructions and Dynamics in South America – 2k initiative that provides the ideal framework for the integration of the various palaeoclimatic subdisciplines and palaeo-science, thereby jump-starting and fostering multidisciplinary research into environmental change on centennial and millennial timescales.

Links between tropical Pacific seasonal, interannual and orbital variability during the Holocene

The El Niño/Southern Oscillation (ENSO) is the leading mode of interannual climate variability. However, it is unclear how ENSO has responded to external forcing, particularly orbitally induced changes in the amplitude of the seasonal cycle during the Holocene. Here we present a reconstruction of seasonal and interannual surface conditions in the tropical Pacific Ocean from a network of high-resolution coral and mollusc records that span discrete intervals of the Holocene. We identify several intervals of reduced variance in the 2 to 7 yr ENSO band that are not in phase with orbital changes in equatorial insolation, with a notable 64% reduction between 5,000 and 3,000 years ago. We compare the reconstructed ENSO variance and seasonal cycle with that simulated by nine climate models that include orbital forcing, and find that the models do not capture the timing or amplitude of ENSO variability, nor the mid-Holocene increase in seasonality seen in the observations; moreover, a simulated inverse relationship between the amplitude of the seasonal cycle and ENSO-related variance in sea surface temperatures is not found in our reconstructions. We conclude that the tropical Pacific climate is highly variable and subject to millennial scale quiescent periods. These periods harbour no simple link to orbital forcing, and are not adequately simulated by the current generation of models.

Fire, climate and vegetation linkages in the Bolivian Chiquitano Seasonally Dry Tropical Forest

South American seasonally-dry tropical forests (SDTF) are critically endangered, with only a small proportion of their original distribution remaining. This paper presents a 12,000 year reconstruction of climate change, fire and vegetation dynamics in the Bolivian Chiquitano SDTF, based upon pollen and charcoal analysis, to examine the resilience of this ecosystem to drought and fire. Our analysis demonstrates a complex relationship between climate, fire and floristic composition over multi-millennial time scales, and reveals that moisture variability is the dominant control upon community turnover in this ecosystem. Maximum drought during the early Holocene, consistent with regional drought reconstructions, correlates with a period of significant fire activity between 8,000 and 7,000 cal yr BP which resulted in a decrease in SDTF diversity. As fire activity declined, but severe regional droughts persisted through the mid-Holocene, SDTF, including Anadenanthera and Astronium, became firmly established in the Bolivian lowlands. The trend of decreasing fire activity during the last two millennia promotes the idea among forest ecologists that SDTF are threatened by fire. Our analysis shows that the Chiquitano seasonally dry biome has been more resilient to Holocene changes in climate and fire regime than previously assumed, but raises questions over whether this resilience will continue in the future under increased temperatures and drought coupled with a higher frequency anthropogenic fire regime.

Spectral analysis and modeling of microcyclostratigraphy in late Paleozoic glaciogenic rhythmites, Parana Basin, Brazil

We investigate the depositional time scale of lithological couplets (fine sandstone/siltstone-siltstone/mudstone) from two distinctive outcrops of Permo-Carboniferous glacial rhythmites in the Itarare Group (Parana Basin, Brazil). Resolving the fundamental issue of time scale for these rhythmites is important in light of recent evidence for paleosecular variation measured in these sequences. Spectral analysis and tuning of high-resolution gray scale scans of sediment core microstratigraphy, which comprises pervasive laminations, reveal a comparable spectral content at both localities, with a frequency suite interpreted as that of short-term climate variability of Recent and modern times. This evidence for decadal- to centennial-scale deposition of these lithological couplets is discussed in light of the `varvic` character, i.e., annual time scale that was previously assumed for the rhythmites.

Practices in social media in the travel education business

Praticas na midia social se refere a vista ou a percepcao de uma marca nao so com base em suas ofertas e servicos, mas tambem sobre seus valores e cultura como percebido principalmente pelos consumidores. As organizacoes podem utilizer a imagem que é interessante e aceitavel para os clients. Nos ultimos anos, uma das formas que as organizacoes de forma consistente comercializar ou publicitar a sua marca envolve midias sociais. O ojetivo deste estudo é explorer quais sao as praticas de midia social no negocio de educacao de viagens. Para obter os dados, a pesquisadora entrevistou pessoas de seis empresas de educacao de viagens e cotejadas informacoes sobre o tema a partir de fonts primarias e secundarias existentes. O pesquisador conduziu a pesquisa para determiner praticas de marketing de midia social em que se aplicam nos sectores do turismo e educacao. Com base nos dados obtidos pelo pesquisador, as praticas de marketing de midia social incluem a utilizacao de plataformas de midia social com um alcance internacional generalizada tipo Facebook, Twitter, Instagram e YouTube. Outra estratégia é para postar constantemente as atualizações que não são apenas interessante, mas também informativo sobre os produtos e serviços oferecidos por uma marca ou organização. As empresas ou organizações devem também interagir com os clientes ou clientes on-line, a fim de manter os interesses deste último em ofertas e serviços da ex. O envolvimento do cliente é uma das razões por que os clientes optam por seguir as empresas on-line através da mídia social. A pesquisa também revela outras vantagens e benefícios da mídia social que constituem as melhores práticas, tais como a conversão de não-clientes para os clientes, o aumento da presença da mídia para aumentar a popularidade, a comunicação eficaz das metas e objetivos organizacionais, bem como a formação de um bom relacionamento com os clientes. As organizações também podem usar turístico criado conteúdo (TCC) e outros tipos de conteúdo para orientar a tomada de decisão no desenvolvimento do produto gerado pelo usuário.

Antecedents of e-loyalty and electronic word-of-mouth

O objetivo principal da dissertação foi o de examinar a relação entre lealdade (e-loyalty) e o boca-a-boca (eWOM) no contexto do varejo eletrônico. Como objetivo secundário, foi feito uma verificação da significância das variáveis preditoras de e-loyalty. Essa pesquisa foi focada em um tipo de produto/serviço: compra de livros através da internet. Duzentos e quarenta e dois questionários online foram respondidos por um público representativo da geração Y (millennials), e rresidentes em diferentes localidades no Brasil e nos Estados Unidos. A análise de dados foi efetuada pela aplicação do método PLS-SEM sobre um modelo de pesquisa cuidadosamente formulado com base em resultados empíricos prévios. Enquanto que a relação entre e-loyalty e eWOM foi classificada como fraca, um ambiente de boca-a-boca online de alta qualidade representou uma variável preditora significativa para o sentimento de e-loyalty. Todas as variáveis preditoras foram classificadas como significativas nesse estudo, sendo que comprometimento tem o efeito mais forte sobre a variável e-loyalty.

Acupuntura: bases científicas e aplicações

A acupuntura visa à terapia e à cura das enfermidades pela aplicação de estímulos através da pele, com a inserção de agulhas em pontos específicos. Essa técnica esteve isolada do mundo ocidental durante milênios, distanciando sua forma de raciocínio e linguagem da cultura ocidental. Isto restringe sua aceitação no Ocidente, sendo considerada mística e sem base científica. Além disso, a prática da acupuntura no Ocidente se depara com deficiências no ensino e difusão científica. Porém, a eficácia dessa terapia levou a Organização Mundial de Saúde a listar enfermidades que podem ser tratadas pela acupuntura e, recentemente, essa técnica foi reconhecida como especialidade médica veterinária no Brasil. A pesquisa da acupuntura reveste-se, portanto, de grande interesse, na medida em que poderá traduzir conhecimentos milenares, contribuindo para sua aceitação e incorporação.

Aspartic acid racemization dating of Holocene brachiopods and bivalves from the southern Brazilian shelf, South Atlantic

The extent of racemization of aspartic acid (Asp) has been used to estimate the ages of 9 shells of the epifaunal calcitic brachiopod Bouchardia rosea and 9 shells of the infaunal aragonitic bivalve Semele casali. Both taxa were collected concurrently from the same sites at depths of 10 m and 30 m off the coast of Brazil. Asp D/L values show an excellent correlation with radiocarbon age at both sites and for both taxa (r(Site)(2) (9) (B. rosea) = 0.97 r(Site)(2) (1) (B.) (rosea) = 0.997, r(Site)(2) (9) (S.) (casali) = 0.9998, r(2) (Site) (1) (S.casali) = 0.93). The Asp ratios plotted against reservoir-corrected AMS radiocarbon ages over the time span of multiple millennia can thus be used to develop reliable and precise geochronologies not only for aragonitic mollusks (widely used for dating previously), but also for calcitic brachiopods. At each collection site, Bouchardia specimens display consistently higher D/L values than specimens of Semele. Thermal differences between sites are also notable and in agreement with theoretical expectations, as extents of racemization for both taxa are greater at the warmer, shallower site than at the cooler, deeper one. In late Holocene marine settings, concurrent time series of aragonitic and calcitic shells can be assembled using Asp racemization dating, and parallel multi-centennial to multi-millennial records can be developed simultaneously for multiple biomineral systems. (c) 2006 University of Washington. All rights reserved.

À sombra dos jequitibás: patrimônio ambiental e políticas públicas na criação e implantação do Parque Estadual de Vassununga – SP (1969-2005)

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

Agricultura familiar: o processo de formação para sustentabilidade na comunidade de Marupaúba município de Tomé-Açu-PA

O presente estudo se constitui em uma reflexão sobre a formação de agricultores familiares ribeirinhos e a sustentabilidade, a partir de um processo implementado pela Prefeitura de Tomé-Açu/PA na Comunidade de Marupaúba, nas gestões municipais compreendidas entre os anos de 2000 a 2008. Tem como objetivo analisar como a educação planejada e executada via políticas públicas e de governo para os agricultores familiares, alteram sua forma de produzir traduzindo-se em sustentabilidade econômica e social para essas famílias. Para tal, foi revisado, de forma pontual, a história da agricultura no Brasil; a constituição da Política Agrícola, desde a colonização até os dias de hoje e como parte dela, a assistência técnica utilizada pelo Estado como estratégia de formação para os agricultores e ainda, o processo implementado pela Prefeitura na Comunidade e qual sua contribuição para a sustentabilidade das famílias atendidas. Utilizaram-se métodos de pesquisa bibliográfica, documental e de campo. Na pesquisa de campo, realizaram-se entrevistas semi-estruturadas com 20 % dos membros da Associação de Moradores. Analisaram-se os dados qualitativos e quantitativos, visando compreender que conhecimentos, habilidades e atitudes foram adquiridas ao longo do processo. Enquanto resultado, chegou-se ao entendimento de que a sustentabilidade do ponto de vista do capital não foi alcançada. Como os cabanos, os agricultores familiares da Comunidade de Marupaúba, resistem ao poder do grande capital e mantém sua cultura com práticas milenares de produção.

Soroprevalência de testes rápidos (ML Flow) em casos de hanseníase e contatos intradomiciliares em municípios endêmicos do Pará

A hanseníase, doença milenar, ainda constitui um grande desafio para a saúde pública, inclusive no que se refere a diagnóstico precoce e vigilância em saúde. Com objetivo de estimar a soroprevalência de anticorpos antiPGL-1 através do teste rápido ML-Flow em casos de hanseníase e seus contatos intradomiciliares de municípios endêmicos do Pará, realizou-se um estudo transversal incluindo 73 casos novos de hanseníase e 135 contatos intradomiciliares, selecionados no período de abril de 2011 a janeiro de 2012, nas unidades de referência para tratamento de hanseníase nos municípios de Belém, Marituba, Igarapé-Açú e Santarém. Os resultados demonstraram uma prevalência de 14,8/10.000hab de casos de hanseníase entre os contatos examinados. A soropositividade do ML Flow nos casos índices foi de 53,42% em pacientes multibacilares e 13,33% nos contatos intradomiciliares. Houve associação direta de positividade do ML Flow nos contatos intradomiciliares com o índice baciloscópico do caso índice. Não houve associação direta do tempo de convivência e a consanguineidade do caso índice em relação ao teste ML Flow. Houve associação entre a positividade do teste ML Flow e a realização da vacina BCG entre os contatos. Estes resultados indicam que a introdução do teste ML Flow poderia servir como instrumento auxiliar no monitoramento dos casos e seus contatos, tornando-se de grande relevância na vigilância epidemiológica da hanseníase.