This review comes from a themed issue on Environmental change issues

ABSTRACT

Although there have been advances in methods for extracting information about dispersal processes, it is still very difficult to measure them. Predicting dispersal groups using single readily-measured traits would facilitate the emergence of instructive comparisons among ecological strategies of plants and offer a path towards improved synthesis across field experiments. The leaf-height-seed scheme consists of three functional traits: specific leaf area, plant canopy height, and seed mass. We tested, applying logistic regression analysis, whether these traits are potential predictors of dispersal guilds in a disjoint cerrado woodland site in southeastern Brazil. According to our results, none of the plant traits studied could predict dispersal guild; this means that abiotically and biotically dispersed species showed similar values of specific leaf area, height, and seed mass. The species of both guilds exhibited sclerophylly, probably a result of the typical soil nutrient deficiency of cerrado, which also may have placed constraints upon plant canopy height regardless of the dispersal mode. In the cerrado, some abiotically dispersed trees might present higher than expected seed mass as support to the investment in high root-to-shoot ratio at the seedling stage. Seeds of birddispersed species are limited in size and mass because of the small size of most frugivorous birds. Since soil nutrient quality might contribute to the similarity between the dispersal guilds regarding the three traits of the scheme, other plant traits (e.g., root depth distribution and nutrient uptake strategy) that detail the former should be considered in future predictive studies.Keywords: savanna, dispersal groups, functional traits, logistic regression, ecological strategy.Podemos prever guildas de dispersão com base no esquema folha-altura-semente em um cerrado sensu stricto disjunto? ResumoEmbora tenham ocorrido avanços nos métodos de aquisição de informações sobre os processos de dispersão, ainda é difícil medi-los. Predizer grupos de dispersão usando atributos simples e práticos facilitaria o aparecimento de comparações instrutivas entre as estratégias ecológicas das plantas e ofereceria um caminho em direção à síntese efetiva de experimentos de campo. O esquema Folha-Altura-Semente consiste em três atributos funcionais: área foliar específica, altura e massa da semente. Testamos, aplicando análise de regressão logística, se esses atributos são potenciais previsores das guildas de dispersão em uma área disjunta de cerrado sensu stricto no Sudeste brasileiro. Segundo os nossos resultados, nenhum dos atributos estudados pôde prever a guilda de dispersão. Isso significa que espécies abiótica e bioticamente dispersas apresentaram valores similares de área foliar específica, altura e massa da semente. As espécies de ambas as guildas exibiram esclerofilia, provavelmente um resultado da deficiência nutricional típica dos solos do cerrado, o que, por sua vez, pode ter limitado à altura das espécies independentemente do seu modo de ...

Architectural concrete surfaces are a durable solution, but their deterioration process is unavoidable and begins as soon as the element is built. This study establishes a methodology for predicting the service life of architectural concrete surfaces, through the application of the factor method. For this purpose, 239 architectural concrete surfaces in in-service conditions are analysed. Different durability factors are studied and their impact in the service life of architectural concrete surfaces is evaluated. Different scenarios are analysed for the quantification of the durability factors. Scenario 4 presents the best results, leading to a higher similarity between the estimated service lives predicted by the factor method and obtained by the graphical method. The application of the factor method, as described in this study, allows one to predict the service life of architectural concrete surfaces. An estimated service life ranging between 43 and 48 years was obtained, which agrees with the literature and empirical knowledge.