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Here we provide the 'Global Spectrum of Plant Form and Function Dataset', containing species mean values for six vascular plant traits. Together, these traits -plant height, stem specific density, leaf area, leaf mass per area, leaf nitrogen content per dry mass, and diaspore (seed or spore) mass - define the primary axes of variation in plant form and function. The dataset is based on ca. 1 million trait records received via the TRY database (representing ca. 2,500 original publications) and additional unpublished data. It provides 92,159 species mean values for the six traits, covering 46,047 species. The data are complemented by higher-level taxonomic classification and six categorical traits (woodiness, growth form, succulence, adaptation to terrestrial or aquatic habitats, nutrition type and leaf type). Data quality management is based on a probabilistic approach combined with comprehensive validation against expert knowledge and external information. Intense data acquisition and thorough quality control produced the largest and, to our knowledge, most accurate compilation of empirically observed vascular plant species mean traits to date.
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BACKGROUND AND OBJECTIVES: Video conferencing technology (telemedicine) can be applied to many settings within the medical community; we assessed the feasibility of its use in conducting observations of faculty at remote family medicine teaching sites. METHODS: We deployed seven telemedicine units to five family medicine residency sites and two observation stations within our division. Practice managers and physician faculty members received on-site training on the basic functionality of the technology, as well as "best practices" and minor troubleshooting techniques. Quick reference guides and other support documents were developed and provided for each site. During the remote faculty observation, two observers simultaneously viewed the resident being precepted, assessing the faculty member using a standardized tool. After the experience, all participants were asked to complete a survey on the usability of the technology. RESULTS: Nineteen observations were successfully conducted from November 2011 to December 2012. From a qualitative perspective, faculty accepted this as a viable means of faculty development. Minor technical hurdles were captured in the survey and improved upon as staff and faculty became more comfortable with the technology and as our technical capabilities allowed. Overall, the technology was rapidly accepted into the practices. CONCLUSIONS: Video teleconferencing represents a valuable tool that contributes to the development of faculty by making observation available to numerous sites, including remote areas that may have been previously challenging to reach due to logistics. Recent improvements in technology should make the process easier and allow more aspects of the encounters to be readily observed.
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Docentes de Medicina/organização & administração , Internato e Residência/métodos , Pacientes Ambulatoriais , Telemedicina/organização & administração , Competência Clínica , Medicina de Família e Comunidade/educação , Interface Usuário-ComputadorRESUMO
The origin of fire-adapted lineages is a long-standing question in ecology. Although phylogeny can provide a significant contribution to the ongoing debate, its use has been precluded by the lack of comprehensive DNA data. Here, we focus on the 'underground trees' (=geoxyles) of southern Africa, one of the most distinctive growth forms characteristic of fire-prone savannas. We placed geoxyles within the most comprehensive dated phylogeny for the regional flora comprising over 1400 woody species. Using this phylogeny, we tested whether African geoxyles evolved concomitantly with those of the South American cerrado and used their phylogenetic position to date the appearance of humid savannas. We found multiple independent origins of the geoxyle life-form mostly from the Pliocene, a period consistent with the origin of cerrado, with the majority of divergences occurring within the last 2 million yr. When contrasted with their tree relatives, geoxyles occur in regions characterized by higher rainfall and greater fire frequency. Our results indicate that the geoxylic growth form may have evolved in response to the interactive effects of frequent fires and high precipitation. As such, geoxyles may be regarded as markers of fire-maintained savannas occurring in climates suitable for forests.
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Incêndios , Florestas , Pradaria , Adaptação Biológica , África , Biodiversidade , Evolução Biológica , Brasil , Ecossistema , FilogeniaRESUMO
Ecologists have long sought to understand the factors controlling the structure of savanna vegetation. Using data from 2154 sites in savannas across Africa, Australia, and South America, we found that increasing moisture availability drives increases in fire and tree basal area, whereas fire reduces tree basal area. However, among continents, the magnitude of these effects varied substantially, so that a single model cannot adequately represent savanna woody biomass across these regions. Historical and environmental differences drive the regional variation in the functional relationships between woody vegetation, fire, and climate. These same differences will determine the regional responses of vegetation to future climates, with implications for global carbon stocks.
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Clima , Ecossistema , Incêndios , Árvores , África , Austrália , Umidade , Modelos Biológicos , América do SulRESUMO
⢠We aimed to identify the limits of savanna across Africa, Australia and South America. We based our investigation on the rich history of hypotheses previously examined: that the limits of savanna are variously determined by rainfall, rainfall seasonality, soil fertility and disturbance. ⢠We categorized vegetation on all continents as 'savanna' (open habitats with a C(4) grass layer) or 'not-savanna' (closed habitats with no C(4) grass layer) and used a combination of statistical approaches to examine how the presence of savanna varied as a function of five environmental correlates. ⢠The presence of savanna is constrained by effective rainfall and rainfall seasonality. Soil fertility is regionally important, although the direction of its effect changes relative to rainfall. We identified three continental divergences in the limits of savanna that could not be explained by environment. ⢠Climate and soils do not have a deterministic effect on the distribution of savanna. Over the range of savanna, some proportion of the land is always 'not-savanna'. We reconciled previous contradictory views of savanna limits by developing a new conceptual framework for understanding these limits by categorizing environmental factors into whether they had a positive or negative effect on woody growth and the frequency of disturbance.