Data for 'Extraction of tree and stand parameters and detection of their dynamics in subtropical forest plantations with multitemporal handheld laser scanning data'

This dataset includes field survey reference data, handheld LiDAR data, and the corresponding individual tree segmentation results. Field survey reference data: The field survey reference dataset contains information from 32 forest sample plots provided in Excel format (Field measurement and multitemporal HLS data segmentation results.xlsx), including 12 eucalyptus plots, 10 Masson pine plots, and 10 Chinese fir plots. The data were collected in subtropical China at the Yuanling Forestry Farm in Fujian Province for the eucalyptus plots, and at the Baisha Forestry Farm in Fujian Province for the Masson pine and Chinese fir plots. Field personnel established plots measuring either 20 m × 20 m or 25.82 m × 25.82 m. For each tree within a plot, diameter at breast height (DBH) was measured at 1.3 m above ground using a diameter tape. The field survey records include individual-tree DBH, tree species, and stand age at the time of the initial plot survey. Handheld LiDAR data: Handheld LiDAR data were collected using a LiGripH 120 device, which has a scanning field of view of 280° × 360°, a measurement range of 120 m, and a scan rate of 320,000 points per second. During data acquisition, operators walked along a zigzag (“Z”) trajectory within each plot to capture point clouds. LiDAR surveys were conducted during the same period as the corresponding field surveys. The handheld LiDAR data are provided in LAS format and compressed as ZIP file (handheld LiDAR data.zip). Handheld LiDAR segmentation results: The handheld LiDAR point clouds were clipped according to the plot boundaries and segmented into individual trees using the Comparative Shortest-Path (CSP) algorithm. DBH was measured from a horizontal point-cloud slice at 1.3 m above ground level using a least-squares circle-fitting method. Tree height was defined as the maximum Z coordinate within each segmented individual-tree point cloud. The matched multitemporal individual-tree segmentation results for each plot are provided in Excel format (Field measurement and multitemporal HLS data segmentation results.xlsx). All point cloud processing was conducted using LiDAR360 software.