22 research outputs found

    Facilitation and allelopathy mediate phylogenetic and functional diversity under Atlantic Rainforest trees

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    Plant phylogeny, diversity, and production of germination inhibiting chemicals can be used as patterns for inferring key drivers of plant community construction and assembly. We conducted the study in a restoration area of Atlantic Rainforest from Southeast Brazil. In this context, we aimed to investigate community assembly rules by simultaneously evaluating the relationships of species with a phylogenetic, functional, and ecophysiological (allelopathy) approach and multifaceted β diversity (taxonomic, phylogenetic, and functional). We measured the plant canopy height and diameter at soil height for all individuals and determined successional group and dispersal syndrome for all species regenerating in open areas and below 18 adult individuals of each tree species Bixa atlantica Antar & Sano, Inga laurina (Sw.) Willd., Joannesia princeps Vell. and Senna multijuga subsp. multijuga var. verrucosa (Vogel) H.S.Irwin & Barneby. Phylogenetic and functional indexes of community structure were calculated with the net relatedness index and the nearest taxon index. Taxonomic, phylogenetic, and functional diversities (respectively, TD, PD, and FD) for the regenerating community in each area were calculated and pairwise comparisons were made for TD, FD, and PD components of β diversity. Tests of tree species allelopathy derived from leaf extract were performed with seeds of Lactuca sativa L. (Asteraceae). The effects of diversity and extracts on seed germination were analyzed using generalized linear models. The phylogenetic and functional structure of the regenerating communities under the four tree species did not differ from random for the four studied tree species. The PD was significantly higher for the communities that regenerated under Joannesia, while the FD was higher under both Joannesia and Senna, compared to communities from open sites, evidencing a facilitation mechanism for these two species. Only Senna and Inga differed from random in relation to β TD and β FD, suggesting possible environmental changes in these areas. Seeds irrigated with the extracts of Inga, Joannesia, and Senna inhibited germination in an intermediate way, whereas seeds irrigated with Bixa extract had only 1 % germination, indicating allelopathic effects. In this way, the planted species directly influence the organization of communities that regenerate below their canopies. It is therefore important to choose species that can contribute to improving diversity, and thus favor the success of restoration projects

    Epidemiologia e tratamento do traumatismo dentoalveolar em crianças e adolescentes: uma revisão da literatura / Epidemiology and treatment of dental alveolar traumatism in children and adolescents: a literature review

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    O trauma dentoalveolar tem como etiologia fatores de violência externa, e acomete com maior frequência crianças e adolescentes. Condutas equivocadas do próprio individuo lesado ou de seus responsáveis, na maioria das vezes por falta de informação, tendem a complicar e desfavorecer o prognóstico do tratamento odontológico. O objetivo desse trabalho é avaliar o perfil epidemiológico de crianças e adolescentes frente ao trauma dentoalveolar, bem como discutir sobre os protocolos de tratamento disponíveis na literatura mediante cada caso específico, o que poderá auxiliar na tomada de decisões clínicas. Estima-se que duas em cada três crianças podem apresentar algum tipo de lesão dentoalveolar por trauma, sendo mais comuns nos indivíduos do sexo masculino, em detrimento do feminino. Os traumas dentoalveolares são divididos em dois grandes grupos: fraturas de tecidos duros e lesões nos tecidos moles. Sendo a avulsão o trauma de maior complexidade terapêutica e de prognóstico, quando tratado com menos de 60 minutos o prognóstico é favorável. Além disso soluções de armazenamento até o tratamento podem contribuir de forma significativa para o sucesso terapêutico odontológico

    Data from: Patterns of taxonomic and functional diversity of termites along a tropical elevational gradient

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    Patterns of termite richness along elevation gradients may be related to different responses by termite functional groups to changes in environmental conditions. We investigated the distribution of termite species richness along an elevational gradient of cerrado and rupestrian grasslands in the Espinhaço Mountain Range, in Brazil. Fifty termite species were recorded, with the family Termitidae being dominant; 16 species are endemic to open areas of cerrado and 1 species, Cortaritermes rizzinii, is endemic and restricted to mountaintop grassland habitats. Termite richness declined with increasing elevation, with the main factors associated with the reduction being climactic (air temperature, air and soil humidity, and radiation) and vegetation variables. Different termite communities were found along the elevational gradient, which were also strongly influenced by changes in climate and vegetation. On the other hand, the same functional groups were present at the different elevations, although represented by different species

    Dung Beetles along a Tropical Altitudinal Gradient: Environmental Filtering on Taxonomic and Functional Diversity.

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    Mountains provide an interesting context in which to study the many facets of biodiversity in response to macroclimate, since environmental conditions change rapidly due to elevation. Although the decrease in biodiversity with increasing elevation is generally accepted, our understanding of the variation of functional diversity along altitudinal gradients is still poorly known. The partitioning of diversity into spatial components can help to understand the processes that influence the distribution of species, and these studies are urgently needed in face of the increasing threats to mountain environments throughout the world. We describe the distribution of dung beetle diversity along an altitudinal gradient on a tropical mountain in southeastern Brazil, including the spatial partitioning of taxonomic and functional diversities. The altitudinal gradient ranged from 800 up to 1400 m a.s.l. and we collected dung beetles at every 100 m of altitude. We used the Rao Index to calculate γ, α and β diversity for taxonomic and functional diversity of dung beetles. Climatic, soil and vegetation variables were used to explain variation in community attributes along the altitudinal gradient. Dung beetle richness declined with altitude and was related to climatic and vegetation variables, but functional diversity did not follow the same pattern. Over 50% of γ taxonomic diversity was caused by among altitudes diversity (β), while almost 100% of functional diversity was due to the α component. Contrasting β taxonomic with β functional diversity, we suggest that there is ecological redundancy among communities and that the environment is filtering species in terms of the Grinnellian niche, rather than the Eltonian niche. β taxonomic diversity is caused mainly by the turnover component, reinforcing the hypothesis of environmental filtering. Global warming may have strong effects on mountain communities due to upslope range shifts and extinctions, and these events will lead to an even larger than previously expected loss of diversity as dung beetles γ taxonomic diversity is caused mainly by the β component

    High Temporal Beta Diversity in an Ant Metacommunity, With Increasing Temporal Functional Replacement Along the Elevational Gradient

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    Ecological communities vary considerably in space and time and understanding such changes has fundamental relevance for ecology and conservation sciences. Mountains provide an excellent scenario for studies addressing spatial and temporal variation, as they vary in conditions and resources in a small geographic region. Here, we aimed to understand the patterns of variation in ant metacommunity composition across time and along an elevational gradient in a tropical mountain, focusing both on the taxonomic and functional facets of diversity. We used a β-diversity metric and broke it into nestedness and turnover to estimate short-term temporal changes in ant metacommunity composition. We tested the following hypotheses: (i) taxonomic and functional temporal β-diversity increase along the elevational gradient and (ii) turnover is the main component driving taxonomic temporal β-diversity and nestedness for functional temporal β-diversity. Rejecting our first hypothesis, we found that both taxonomic and functional temporal β-diversity did not increase with elevation. Yet, the values were always high, indicating that both species and functional traits are highly variable over time. In accordance with our second hypothesis, we found that turnover was the main component of taxonomic β-diversity. Yet adding complexity to our hypothesis, the contribution of nestedness to functional β-diversity decreased with increasing elevation. These results suggest that at low elevations, the turnover in species composition may then cause changes in trait composition because of the loss of some traits, yet preserving the most common functions (nested functional communities), while at high elevations functional capabilities may change over time (turnover of traits). In the context of global warming, where tropical mountain insects are expected to change their distributional range upwards, it is extremely important to consider the importance of the turnover on the temporal variation in functional traits and functions of ant metacommunity at higher elevations

    Soil arthropod community responses to restoration in areas impacted by iron mining tailings deposition after FundĂŁo dam failure

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    In 2015, the failure of the FundĂŁo dam in Mariana, Brazil released ~43 million m 3 of iron mining tailings into the environment. Despite restoration initiatives in the following years, few studies-and most focused on revegetation-have evaluated the effectiveness of the restoration process in areas impacted by the disaster. We aimed to evaluate the responses of the arthropod community in areas impacted by iron mining tailings deposition from the FundĂŁo dam that is in the restoration process. We defined sampling units in the riparian zone of the Gualaxo do Norte River, which is under restoration, and in a native not impacted riparian zone. We collected soil arthropods using pitfall traps and sampled environmental variables in the same sites. We used generalize least squares models (GLS) to test if the restored areas already presented values of arthropod diversity and functional group abundance similar to the reference area and to test which environmental variables are influencing arthropod diversity. We also tested how large the differences of arthropod community composition between the study areas and used the index of indicator species (IndVal) to verify which species could be used as an indicator of reference or restoration areas. The diversity of arthropods and the functional groups of detritivores and omnivores were higher in the native riparian zone. Understory density, soil density, organic matter content, and microbial biomass carbon were the environmental variables that significantly explained the diversity and species composition of arthropods. We show that restoration areas still have different soil arthropod diversity values and community composition when compared to reference areas. Evaluating the response of the arthropod community to the restoration process and long-term monitoring are essential to achieve a satisfactory result in this process and achieve a self-sustaining ecosystem

    Linking Biodiversity, the Environment and Ecosystem Functioning : Ecological Functions of Dung Beetles Along a Tropical Elevational Gradient

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    Biodiversity loss and anthropogenic environmental changes are known to impact ecosystem functions and services. However, there are still some uncertainties such as confounding environmental factors other than community attributes that affect ecosystem functioning. Our goal was to understand what factors influence the performance of Scarabaeinae dung beetle functions, testing the hypothesis that both community attributes and environmental variables influence the performance. Toward this aim, we collected dung beetles along an elevational gradient (800–1400 m a.s.l.) in the Espinhaço mountain range (Brazil) and quantified dung beetle functions, that is, dung removal, soil excavation and secondary seed dispersal. We recorded data on environmental factors related to climate, soil and vegetation and evaluated their effects on dung beetle functions. Dung beetle ecological functions declined with elevation and the decrease was more pronounced than richness, indicating that there are other factors involved in functions performance besides diversity of beetles. Indeed, we found that the ecological functions measured were dependent on both dung beetle community attributes and environmental factors. Climate, soil and vegetation influenced dung beetle function performance as much as richness, abundance and body size. Dung beetle functional diversity did not explain any of the functions measured. Our study demonstrates that ecological functions are directly influenced by both community attributes and environmental variables and confirms the link between biodiversity, environment and ecosystem functioning

    Termite Community Data

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    In this file we present data of termite species per transect and per elevation. We also present the values of the environmental variables used in the study. In the last two spreadsheets we present data of functional distances and functional groups of the termite species found in our study
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