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

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.