Quantifying Forest Dynamics with Terrestrial Laser Scanning Data

In the context of global climate change, understanding forest dynamics and formulating sustainable forest development strategies require accurate quantification of forest structural changes over time. However, the majority of studies have focused on exploring forest structure at one specific time point, lacking repeated observations of forest structure. This limitation hinders the comprehensive understanding of structural dynamics in forests, particularly its link with changes in forest ecosystem functionality. To address this issue, this study proposes a method for quantifying forest structural dynamics using bi-temporal terrestrial laser scanning (TLS) data. We utilized bi-temporal TLS data in combination with a quantitative structure model (QSM) algorithm, to reconstruct 3D models of individual trees. Subsequently, tree parameters including diameter at breast height (DBH), tree height, crown projection area (CPA), crown volume (CV) and biomass were extracted. By quantifying the changes in these parameters and analyzing their relationships with the 3D spatial structure of trees, a comprehensive analysis was conducted to quantitatively assess forest dynamics. The results indicate that bi-temporal TLS data possesses unprecedented advantages and tremendous potential in quantifying forest dynamics.