Non-destructive equations to estimate the leaf area of Styrax pohlii and Styrax ferrugineus

Abstract

We developed linear equations to predict the leaf area (LA) of the species Styrax pohlii and Styrax ferrugineus using the width (W) and length (L) leaf dimensions. For both species the linear regression (Y=α+bX) using LA as a dependent variable vs. W × L as an independent variable was more efficient than linear regressions using L, W, L 2 and W 2 as independent variables. Therefore, the LA of S. pohlii can be estimated with the equation LA=0.582+0.683WL, while the LA of S. ferrugineus follows the equation LA=-0.666+0.704WL. Keywords:Brazilian savanna, Styracaceae, validation, regression analysis, linear models. Equações lineares para estimativa de área foliar de Styrax pohlii e Styrax ferrugineus ResumoForam determinadas equações lineares para estimar a área foliar (AF) de Styrax pohlii e Styrax ferrugineus utilizando dimensões do limbo foliar (C -comprimento, L -largura). O modelo linear (Y=α+bX), utilizando AF vs. C × L, foi mais eficiente que os modelos lineares utilizando C, L, C 2 e L 2 como variáveis independentes na determinação da área foliar de S. pohlii e S. ferrugineus. Assim, a AF de S. pohlii pode ser estimada pelo modelo AF=0,582+0,683CL e a AF de S. ferrugineus pode ser estimada pelo modelo AF=-0,666+0,704CL.

Regression models for estimating leaf area of seedlings and adult individuals of Neotropical rainforest tree species

“…In our study, we adopted the use of linear regression models because they are simpler and provide good estimates for a great number of plant species with different leaf areas and leaf shapes when compared with non-linear regression models (Cristofori et al, 2007;Mazzini et al, 2010;Rouphael et al, 2010;Wang and Zhang, 2012;Souza and Habermann, 2014). In addition, we tested two geometric formulas for estimating LA from simple linear regression models.…”

“…Our results demonstrate that it is not always possible to use models developed for adults in studies with seedlings, and vice-versa. This fact is very critical, since most of the models available in the literature have been developed based upon leaves of adult plants (Cristofori et al, 2007;Mazzini et al, 2010;Rouphael et al, 2010;Wang and Zhang, 2012;Souza and Habermann, 2014). The use of models developed with leaves of adults in studies with Table 4.…”

“…Destructive methods involve leaf harvesting, which can be done using automated leaf area meters, photocopies, planimeters (Tsuda, 1999) and softwares that calculate LA based on scanned images and digital photos (O'Neal et al, 2002;Godoy et al, 2007;Toebe et al, 2010). Nondestructive methods do not require leaf destruction and are based on regression models to estimate LA from leaf linear dimensions, as length (L) and width (W) (Kandiannan et al, 2002;Antunes et al, 2008;Rouphael et al, 2010;Zhang and Pan, 2011;Pompelli et al, 2012;Souza and Habermann, 2014).…”

“…Second, many species have differences in leaf morphological traits between leaf seedlings, saplings and adults, which is related to the regeneration niche (Thomas and Ickes, 1995;Ishida et al, 2005;Houter and Pons, 2012). Even though there are many references of regression models in the literature for predicting of LA in tropical tree species (Antunes et al, 2008;Zhang and Pan, 2011;Pompelli et al, 2012;Souza and Habermann, 2014), we are aware of no published studies aiming to compare regression models developed for both seedlings and adult individuals of tropical trees.…”

Non-destructive linear model for leaf area estimation in Vernonia ferruginea Less

“…Styrax ferrugineus Nees & Mart and Styrax pholii A. DC. (Souza and Habermann, 2014)). Linear models based on length and width leaf measurements have been considered the most simple and efficient models to estimate the leaf area of some species (Demirsoy and Lang, 2010, Giuffrida et al, 2011, Wang and Zhang, 2012.…”