A hidden variables approach: assessing the influence of environmental, flight and processing parameters on LiDAR accuracy in wet heathlands in the northwest of Spain

Notably, maximum height alone explains 75% of the variability, with increases of 7 cm inducing changes of ±40 cm. Moreover, although interactions among parameters had limited impact (between 2 cm and 2 mm, except for slope ±15 cm), they provide insights into the strengths and limitations of LiDAR-derived canopy height models (CHMs) in challenging environments (dense cover and steep areas). Furthermore, flying at a lower altitude, non-repetitive mode, and lower spatial resolutions (DTM 1 m, CHM 0.5 m) were associated with higher vegetation model contribution on average.

Errors also tend to increase in areas where taller vegetation is associated with higher canopy cover, while reduced point density in flight further exacerbated inaccuracies. This approach provides a practical framework for improving precision and managing uncertainties in structurally complex ecosystems.</p>