研究目的
The main objective of this study is to obtain deeper insight into variables that influence estimation of aboveground biomass from ALS data. Specifically, we will evaluate (i) the effect of various ALS point densities and spatial resolutions of input canopy height model rasters on individual tree detection, and (ii) the impact and transferability of site-specific relationships between tree height and stem diameter at breast height (DBH) on estimates of Norway spruce forest AGB in the Czech Republic.
研究成果
The study concludes that ALS input point densities did not influence individual tree detection rates, but spatial resolution of the input CHM rasters had a greater impact. Global DBH models tend to underestimate AGB in young stands and overestimate AGB in mature stands. The study recommends establishing one’s own site-specific models for allometric equations, if possible.
研究不足
The accuracy of ALS-based AGB models can vary by species and forest types. The study also highlights the uncertainty in AGB estimates caused by usage of allometric equation from different sources.