Can we predict dispersal guilds based on the leaf-height-seed scheme in a disjunct cerrado woodland?

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 ...

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“…Researchers found positive correlations of seed size/weight with plant height in fl owering plants (Moles et al, 2004(Moles et al, , 2005Thomson et al, 2011), with leaf length and width in annuals (Chung et al, 1998), and with height in shrub/trees (Jardim & Batalha, 2008). Our results on correlation between seed weight and height confi rm results of the previous studies.…”

An intraspecific application of the leaf-height-seed ecology strategy scheme to forest herbs along a latitudinal gradient

“…The LHS scheme has been used at the species level to compare species groups (Lavergne et al 2003, Jardim and Batalha 2008) and at the community level to compare different forms of management or successional stages (Garnier et al 2004, Moog et al 2005, Golodets et al 2009). To date, the LHS scheme has, to our knowledge, not been used to describe intraspecific trait variation among populations of a single species.…”

“…SLA, for instance, contributes to the potential of a plant to respond to a change in stress exposure, whereas seed mass and plant height influence the ability of a plant to adjust to disturbance effects and other environmental changes (Westoby 1998, Poorter et al 2009). The LHS scheme has been used at the species level to compare species groups (Lavergne et al 2003, Jardim andBatalha 2008) and at the community level to compare different forms of management or successional stages (Garnier et al 2004, Moog et al 2005, Golodets et al 2009). To date, the LHS scheme has, to our knowledge, not been used to describe intraspecific trait variation among populations of a single species.…”

Meaningful traits for grouping plant species across arid ecosystems

“…Moreover, plant height was highly correlated to almost all the other morpho-chemical traits considered in this study. This finding highlighted that plant height is a trait that summarizes fundamental trade-offs associated with the ability to tolerate or avoid environmental stress and grazing disturbance (Briske 1996;Jardim and Batalha 2008;Moles et al 2009;Westoby 1998). Unlike shrubs, perennial grass species only showed heterogeneity in relation to plant height.…”