ABSTRACT
Canopy height is a crucial metric required to accurately quantify the aboveground plant biomass. The study explores the data derived using LiDAR technology from the GeoScience Laser Altimeter System (GLAS) aboard the Ice, Cloud, and Land Elevation satellite (ICESat) to derive canopy height estimates for Northwestern India using four different canopy height models. The interpretation of LiDAR waveforms for the purpose of estimating canopy heights is not straightforward, especially over sloping terrain where vegetation and ground are found at comparable heights. A terrain index derived from the ASTER digital elevation model (DEM) was employed to quantify the topographic relief effects that often plague the accuracy of canopy height estimates over steep terrain. The models that incorporated the terrain index were found to outperform their counterparts, especially over steep slopes, revealing that they were able to successfully account for the pulse-broadening effect. The study highlights the importance of identifying peaks corresponding to the ground location within the LiDAR waveform to yield better canopy height estimates, especially over gentle slopes.
