This data set contains the 2D footprint information of a forest succession dataset in the context of boreal ecosystems survey. The data provides structural and biophysical information on forest state, structure, topography, morphology, disturbance (wildfire, thaw slumps, windfall), thermokarst lake-shore interfaces, among others. The Lidar and multispectral surveys were conducted over 21 selected vegetation transects. Each transect (500m by 200m) contains at least one ground vegetation reference plot (doi:10.1594/PANGAEA.943547). The data was acquired in August and September 2021 (07.08.2021 - 01.09.2021) along a 670 km line segment in Central and Eastern Yakutia (Republic of Sakha), Siberia, Russia. The principal study areas are the intramontane Oymyakon region in the Verkhoyansk mountain range near Lake "Ulu", and the central-eastern Yakutian lowlands with a slightly different ecological setting. A transect was covered by UAV-based Lidar at flight heights between 60-100 m above ground level. Subsequent analysis and segmentation algorithms allow single-tree crown and canopy analysis.

First-order data and further are found in each sub-submission to this data set. Lidar point clouds in .LAS file format, SfM-true-colour point clouds in .LAZ format and multispectral orthoimages in .TIFF format. Second-order data products (e.g. canopy height model, vertical complexity index, elevation quantiles, digital terrain models, spectral vegetation indices) are provided in .TIFF format. Additional derivatives and statistical information covering data and forest-specific aspects are stored in .CSV format. Individual tree crown segments populated with second-order information in .SHP format and transect coverage footprint are provided and .KML format. Additional information is provided in the detailed ReadMe file.Each .zip file contains the following files:- sampling locations as shapefiles- extracted crowns as polygon shapefiles- UAV flightlines as point shapefiles- UAV flight footprints as polygons- Agisoft Metashape 1.7 photogrammetric report- POSPac UAV software diagnostic QC report- YellowScan Cloudstation strip adjusment report- basic Lidar stats, the gap fraction and leaf area density fraction per Lidar flight, extracted with the lidR R package- crown statistics, extracted with the lidR R package- crown master tables containing the attributes Plot-ID; Succession-state; LAT; LON; treeID; Z; Area; NDVI; GNDVI; NDRE; TCARI; PCA1; CHM; CHM_standarddeviation; CHM_density; CHM_entropy; VerticalComplexityIndex; Qz05; Qz10; Qz25; Qz50; Qz75; Qz95; gDSM; gDSM_slope; gDSM_TopographicPositionIndex; INT_min; INT_max; INT_mean; INT_std; TIR (Occasional data gaps may be present)Funding: This data was collected during the international joint Russian-German expedition 'RU-Land_2021_Yakutia' in collaboration between the Alfred-Wegener-Institute, Helmholtz Centre for Polar and Marine Research in Potsdam, and the North-Eastern Federal University of Yakutsk, with UAV flight support by the Technische Universität Berlin. Additional funding for equipment was provided by the "Potsdamer InnoLab für Arktisforschung" grant no. F221-08-AWI/001/002, namely the Brandenburg Ministry for Science, Research and Culture and the Strategischer Call 2020 "Pro Nachhaltigkeit" by the Technische Universität Berlin.