Point cloud index VDR

VDR

(normalized) vertical distribution ratio, (ch - median) / ch, based on BE_H_MAX (ch) and BE_H_MEDIAN (median)

reference: Joerg Mueller et al.: LiDAR-derived canopy structure supports the more-individuals hypothesis for arthropod diversity in temperate forests, Oikos (2018) 127: 814-824, https://doi.org/10.1111/oik.04972