Digital Analysis of Leaf Surface Area: Effects of Shape, Resolution, and Size

Authors

Jeffrey Bradshaw, University of Nebraska-LincolnFollow
Marlin E. Rice, Iowa State University
John W. Hill, Iowa State University

Date of this Version

2007

Comments

Published in JOURNAL OF THE KANSAS ENTOMOLOGICAL SOCIETY 80(4), 2007, pp. 339–347; Copyright 2007 Kansas Entomological Society; Used by permission

Abstract

The effects of shape, size, and capture resolution on digital area measurement were investigated to accurately and precisely estimate leaf surface area. A digital scanner was used to measure two simple shapes (circle and square) at three resolutions (118.159, 236.270 and 472.441 pixels/cm) and five sizes (3.14, 12.58, 28.29, 50.29, and 78.60 cm²). Additionally, the accuracy and precision of two digital scanner models were compared using two shapes (circle and square) of similar size at five resolutions (29.528, 39.370, 59.055, 118.159, 236.270, and 472.440 pixels/cm). A method is described to measure leaf area using an image histogram and photographic software tools (Photoshop^©). This method was validated by comparison of the digitally captured images to a leaf area meter (LI-COR^© 3100). Overall, simple changes in shape have a statistically significant effect on the accuracy of digital measurements of area for some sizes and resolutions.