tLiDAR methodologies can overcome limitations in estimating forest canopy LAI from conventional hemispherical photograph analyses

  • Eric Casella Forestry Commission Research Agency
  • Mathias Disney University College London
  • James Morison Forestry Commission Research Agency
  • Helen McKay Forestry Commission Research Agency
Keywords: TLS, laser, point cloud, gap fraction, equiangular projection, composite hemispherical picture, resolution

Abstract

The hemispherical photography technique has been widely used to assess the three-dimensional reconstruction quality of virtual plant canopy architectures [1]. High-resolution terrestrial Light Detection And Ranging (tLiDAR) has recently been applied for measuring the 3-D characteristics of forest vegetation [2] and specifically the extraction of canopy directional gap fraction [3]. In contrast with the digital hemispherical photography method, sky conditions appear to have little influence on the quality of the data collected by the tLiDAR technique. This study considers the resolution used during both point cloud data acquisition and the computation of equiangular hemispherical images, which may influence the resolving power of this technique in estimating gaps in a forest environment.

Author Biographies

Eric Casella, Forestry Commission Research Agency
Forest Research, Centre for Sustainable Forestry and Climate Change, Farnham, Surrey, GU10 4LH, UK
Mathias Disney, University College London
Department of Geography, London, WC1E 6BT, UK
James Morison, Forestry Commission Research Agency
Forest Research, Centre for Sustainable Forestry and Climate Change, Farnham, Surrey, GU10 4LH, UK
Helen McKay, Forestry Commission Research Agency
Forest Research, Centre for Sustainable Forestry and Climate Change, Farnham, Surrey, GU10 4LH, UK
Published
2013-06-03
Section
1B Reconstructing and observing plant structure