Unearthing belowground bud banks in fire-prone ecosystems.

Despite long-time awareness of the importance of the location of buds in plant biology, research on belowground bud banks has been scant. Terms such as lignotuber, xylopodium and sobole, all referring to belowground bud-bearing structures, are used inconsistently in the literature. Because soil efficiently insulates meristems from the heat of fire, concealing buds below ground provides fitness benefits in fire-prone ecosystems. Thus, in these ecosystems, there is a remarkable diversity of bud-bearing structures. There are at least six locations where belowground buds are stored: roots, root crown, rhizomes, woody burls, fleshy swellings and belowground caudexes. These support many morphologically distinct organs. Given their history and function, these organs may be divided into three groups: those that originated in the early history of plants and that currently are widespread (bud-bearing roots and root crowns); those that also originated early and have spread mainly among ferns and monocots (nonwoody rhizomes and a wide range of fleshy underground swellings); and those that originated later in history and are strictly tied to fire-prone ecosystems (woody rhizomes, lignotubers and xylopodia). Recognizing the diversity of belowground bud banks is the starting point for understanding the many evolutionary pathways available for responding to severe recurrent disturbances.

Towards understanding resprouting at the global scale.

Understanding and predicting plant response to disturbance is of paramount importance in our changing world. Resprouting ability is often considered a simple qualitative trait and used in many ecological studies. Our aim is to show some of the complexities of resprouting while highlighting cautions that need be taken in using resprouting ability to predict vegetation responses across disturbance types and biomes. There are marked differences in resprouting depending on the disturbance type, and fire is often the most severe disturbance because it includes both defoliation and lethal temperatures. In the Mediterranean biome, there are differences in functional strategies to cope with water deficit between resprouters (dehydration avoiders) and nonresprouters (dehydration tolerators); however, there is little research to unambiguously extrapolate these results to other biomes. Furthermore, predictions of vegetation responses to changes in disturbance regimes require consideration not only of resprouting, but also other relevant traits (e.g. seeding, bark thickness) and the different correlations among traits observed in different biomes; models lacking these details would behave poorly at the global scale. Overall, the lessons learned from a given disturbance regime and biome (e.g. crown-fire Mediterranean ecosystems) can guide research in other ecosystems but should not be extrapolated at the global scale.

Root traits explain different foraging strategies between resprouting life histories.

Drought and fire are prevalent disturbances in Mediterranean ecosystems. Plant species able to regrow after severe disturbances (i.e. resprouter life history) have higher allocation to roots and higher water potential during the dry season than coexisting non-resprouting species. However, seedlings of non-resprouters have a higher survival rate after summer drought. We predict that, to counteract their shallow-rooting systems and to maximize seedling survival, non-resprouters have root traits that confer higher efficiency in soil resource acquisition than resprouters. We tested this prediction in seedlings of less than 1.5 months old. We select 13 coexisting woody species (including both resprouters and non-resprouters), grew them in a common garden and measured the following root traits: length, surface, average diameter, root tissue density (RTD), specific root length (SRL), surface:volume ratio (SVR), specific tip density (STD), tip distribution in depth, internal links ratio (ILR), and degree of branching. These root traits were compared between the two resprouting life histories using both standard cross-species and phylogenetic-informed analysis. Non-resprouters showed higher SRL and longer, thinner and more branched laterals, especially in the upper soil layers. The external links (i.e. the most absorptive root region) were also more abundant, longer, thinner and with higher SVR for non-resprouters. The results were supported by the phylogenetic-informed analysis for the root traits most strongly related to soil resource acquisition (SRL, SVR and branching pattern). The seedling root structure of non-resprouters species allows them to more efficiently explore the upper soil layer, whereas seedling roots of resprouters will permit both carbon storage and deep soil penetration.

Physiological differences between root suckers and saplings enlarge the regeneration niche in Eucryphia cordifolia Cav.

Many clonal plants produce vegetative recruits that remain connected to the parent plant. Such connections permit resource sharing among ramets, explaining the high survival rates of vegetative recruits during establishment under suboptimal conditions for sexual regeneration. We propose that differences in the regeneration niches of sexual and vegetative recruits reflect different physiological adjustments caused by parental supply of resources to the ramets. We conducted ecophysiological measurements in saplings and root suckers of Eucryphia cordifolia Cav., a tree species of the temperate rainforest of southern South America. We compared the following traits of saplings and suckers: gas exchange at the leaf level, crown architecture, daily crown carbon balance, biomass allocation to above-ground tissues (leaf-to-stem mass ratio, leaf mass area and leaf area ratio), xylem anatomy traits (lumen vessel fraction, vessel density and size) and stem ring width. We also correlated the growth rates of saplings and suckers with relevant environmental data (light and climate). Saplings showed morphological, architectural and physiological traits that enhance daily crown carbon balance and increase water-use efficiency, in order to supply their growth demands while minimizing water loss per unit of carbon gained. The radial growth of saplings diminished under dry conditions, which suggests a strong stomatal sensitivity to water availability. Suckers have low stomatal conductance, likely because the carbon supplied by the parent plant diminishes the necessity of high rates of photosynthesis. The low responsiveness of sucker growth to temporal changes in water availability also supports the existence of parental supply. The physiological differences between sexual and vegetative recruits satisfactorily explain the ecological niche of E. cordifolia, with saplings restricted to more closed and humid sites.

A evolução da e-audiologia no Brasil e no mundo: uma revisão integrativa / The evolution of e-audiology in Brazil and in the world: an integrative review / La evolución de la e-audiología en Brasil y en el mundo: una revisión integrativa

Introdução: Os termos 'e-audiologia', 'teleaudiologia', 'teleprática em audiologia' e variações, possuem uma característica em comum: avanços tecnológicos na audiologia. Objetivo: O estudo busca avaliar a evolução e desdobramentos da audiologia em modelo remoto no Brasil em comparação a outros países, assim como as vantagens e adversidades proporcionadas por este modelo. Método: Uma revisão integrativa foi realizada por meio de busca e análise de publicações disponíveis nas bases de dados Taylor & Francis Online, PubMed, Scielo, Thieme, ASHAWire e Academia.edu, entre novembro de 2020 e fevereiro de 2021, nos idiomas português brasileiro e inglês. Os termos de busca foram: e-audiologia, e-audiology, teleaudiologia, teleaudiology, telessaúde em audiologia, telehealth in audiology, teleprática em audiologia, telepractice in audiology. Foram considerados artigos publicados de forma gratuita abordando a audiologia em modelo remoto, sem limites ao ano de publicação. Resultados: Foram encontrados 987 artigos, mas apenas 79 foram selecionados para análise na presente revisão. O número de publicações apresentou um aumento nos últimos 5 anos e o Brasil, em comparação a outros países, mostrou bom nível de desenvolvimento em pesquisas na área da teleaudiologia. Conclusão: Não há dúvidas de que a teleaudiologia já possui um impacto significativo e positivo como modelo de atuação audiológica e, assim como em toda evolução, a e-audiologia vem oferecendo, ainda, maiores oportunidades para seus usuários. A insegurança e a incerteza vêm perdendo espaço para pesquisas e atualizações no campo ao redor do mundo, e, mesmo com algumas barreiras a serem enfrentadas, seu crescimento tem possibilitado acesso, autonomia, economia financeira e qualidade.

Introduction: The terms 'e-audiology', 'teleaudiology', 'telepractice in audiology' and variations, have one feature in common: technological advances in audiology. Objective: The study seeks to evaluate the evolution and developments of audiology in a remote model in Brazil compared to other countries, as well as the advantages and adversities provided by this model. Method: An integrative review was carried out by searching and analyzing publications available in the databases: Taylor & Francis Online, PubMed, Scielo, Thieme, ASHAWire and Academia.edu, between November 2020 and February 2021, in Brazilian Portuguese and English. The search words were: e-audiologia, e-audiology, teleaudiologia, teleaudiology, telessaúde em audiologia, telehealth in audiology, teleprática em audiologia, telepractice in audiology. Articles published free of charge addressing audiology in a remote model were considered without limits to the year of publication. Results: 987 articles were found, but only 79 were selected for analysis in this review. The number of publications has increased over the past 5 years and Brazil, compared to other countries, has shown a good level of development in research in the field of teleaudiology. Conclusion: There is no doubt that teleaudiology already has a significant and positive impact as a model of audiological performance and, as in all evolution, e-audiology has been offering even greater opportunities for its users. Insecurity and uncertainty have been losing ground for research and updates in the field around the world and even with some barriers to be faced, their growth has enabled access, autonomy, financial savings and quality.

Introduccíon: Los términos "e-audiología", "teleaudiología", "telepráctica en audiología" y variaciones tienen una característica en común: los avances tecnológicos en audiología. Objetivo: El estudio busca evaluar la evolución y desarrollos de la audiología en un modelo remoto en Brasil en comparación con otros países, así como las ventajas y adversidades que brinda este modelo. Método: Se realizó una revisión integradora mediante la búsqueda y análisis de publicaciones disponibles en las bases de datos Taylor & Francis Online, PubMed, Scielo, Thieme, ASHAWire y Academia.edu, entre noviembre de 2020 y febrero de 2021, en portugués brasileño e inglés. Los términos de búsqueda fueron: e-audiologia, e-audiology, teleaudiologia, teleaudiology, telessaúde em audiologia, telehealth in audiology, teleprática em audiologia, telepractice in audiology. Se consideraron los artículos publicados gratuitamente que abordan la audiología en un modelo remoto, sin límite de año de publicación. Resultado: Se encontraron 987 artículos, pero solo se seleccionaron 79 para el análisis en esta revisión. El número de publicaciones ha aumentado en los últimos 5 años y Brasil, en comparación con otros países, ha mostrado un buen nivel de desarrollo en la investigación en el campo de la teleaudiología. Conclusión: No cabe duda de que la teleaudiología ya tiene un impacto significativo y positivo como modelo de rendimiento audiológico y, como en toda evolución, la e-audiología viene ofreciendo aún mayores oportunidades para sus usuarios. La inseguridad y la incertidumbre han ido perdiendo terreno para las investigaciones y actualizaciones en el campo en todo el mundo, e incluso con algunas barreras que enfrentar, su crecimiento ha permitido el acceso, la autonomía, el ahorro financiero y la calidad.

Postfire responses of the woody flora of Central Chile: Insights from a germination experiment.

Fire is a selective agent shaping plant traits and community assembly in fire-prone ecosystems. However, in ecosystems with no fire history, it can be a cause of land degradation when it is suddenly introduced by humans, as plant species may not be able to respond to such novel disturbance. Unlike other Mediterranean-type ecosystems (MTE) of the world, natural fires have not been frequent during the Quaternary in the matorral of Central Chile, and thus, plant adaptive responses are expected to be uncommon. We evaluated the effect of heat shock on seed survival and germination of 21 native woody plants of the Chilean matorral and compiled information on smoke-stimulation and resprouting, to evaluate the importance of fire-adaptive responses in the context of the other MTE. We found that in the Chilean woody flora negative seed responses to fire cues were more frequent than positive responses. Although resprouting is a relatively widespread trait, fire-stimulated germination is not as common in the Chilean matorral as in other MTE. The seeds of seven endemic species were strongly damaged by fire cues and this should be considered in post-fire restoration planning. However, our results also showed that many species were resistant to elevated doses of heat shock and in some, germination was even stimulated. Thus, future research should focus on the evolutionary causes of these responses. These findings could help to develop strategies for fire management in the Chilean matorral. In addition, they will improve our understanding of the evolutionary forces that shaped this plant community and to better frame this region among the other MTE worldwide.

Effect of three food types on the population growth of Brachionus calyciflorus and Brachionus patulus (Rotifera: Brachionidae)

We compared the population growth of B. calyciflorus and B. patulus using the green alga Chlorella vulgaris, baker's yeast Saccharomyces cerevisiae or their mixture in equal proportions as food. Food was offered once every 24 h in two concentrations (low: 1 x 10(6) and high: 3 x 10(6) cells ml-1) separately for each species. The experiments were terminated after 15 days. In general, at any food type or concentration, B. patulus reached a higher population density. A diet of Chlorella alone supported a higher population growth of both rotifer species than yeast alone. B. calyciflorus and B. patulus achieved highest population densities (103 +/- 8 ind. ml-1 and 296 +/- 20 ind. ml-1, respectively) on a diet of Chlorella at 3 x 10(6) cells ml-1. When cultured using the mixture of Chlorella and yeast, the maximal population densities of B. calyciflorus were lower than those grown on Chlorella. Under similar conditions, the maximal abundance values of B. patulus were comparable in both food types. Regardless of food type and density the rate of population increase per day (r) for B. calyciflorus varied from 0.13 +/- 0.03 to 0.63 +/- 0.04. These values for B. patulus ranged from 0.19 +/- 0.01 to 0.37 +/- 0.01. The results indicated that even though Chlorella was a superior food for the tested rotifers, yeast can be effectively used at low concentrations to supplement algal requirements in rotifer culture systems.