@article{fdi:010086949,
  title = {{M}ulti-sensor airborne lidar requires intercalibration for consistent estimation of light attenuation and plant area density},
  author = {{V}incent, {G}r{\'e}goire and {V}erley, {P}hilippe and {B}rede, {B}. and {D}elaitre, {G}. and {M}aurent, {E}. and {B}all, {J}. and {C}locher, {I}. and {B}arbier, {N}icolas},
  editor = {},
  language = {{ENG}},
  abstract = {{L}eaf area is a key structural characteristic of forest canopies because of the role of leaves in controlling many biological and physical processes occurring at the biosphere-atmosphere transition. {H}igh pulse density {A}irborne {L}aser {S}canning ({ALS}) holds promise to provide spatially resolved and accurate estimates of plant area density ({PAD}) in forested landscapes, a key step in understanding forest functioning: phenology, carbon uptake, transpiration, radiative balance etc. {I}nconsistencies between different {ALS} sensors is a barrier to generating globally harmonised {PAD} estimates. {T}he basic assumption on which {PAD} estimation is based is that light attenuation is proportional to vegetation area density. {T}his study shows that the recorded extinction strongly depends on target detectability which is influenced by laser characteristics (power, sensitivity, wavelength). {T}hree different airborne laser scanners were flown over a wet tropical forest at the {P}aracou research station in {F}rench {G}uiana. {D}ifferent sensors, flight heights and transmitted power levels were compared. {L}ight attenuation was retrieved with an open source ray-tracing code (http://amapvox.org). {D}irect comparison revealed marked differences (upto 25% difference in profile-averaged light attenuation rate and 50% difference at particular heights) that could only be explained by differences in scanner characteristics. {W}e show how bias which may occur under various acquisition conditions can generally be mitigated by a sensor intercalibration. {A}lignment of light weight lidar attenuation profiles to {ALS} reference attenuation profiles is not always satisfactory and we discuss what are the likely sources of discrepancies. {N}eglecting the dependency of apparent light attenuation on scanner properties may lead to biases in estimated vegetation density commensurate to those affecting light attenuation estimates. {A}pplying intercalibration procedures supports estimation of plant area density independent of acquisition characteristics.},
  keywords = {{L}idar ; {ALS} ; {UAV}-{LS} ; {PAD} ; {LAD} ; {F}orest},
  booktitle = {},
  journal = {{R}emote {S}ensing of {E}nvironment},
  volume = {286},
  numero = {},
  pages = {113442 [14 p.]},
  ISSN = {0034-4257},
  year = {2023},
  DOI = {10.1016/j.rse.2022.113442},
  URL = {https://www.documentation.ird.fr/hor/fdi:010086949},
}