Data accompanying Milodowski et al. (Journal of Applied Ecology, 2021): "The impact of logging on vertical canopy structure across a gradient of tropical forest degradation intensity in Borneo"

Abstract

Description: LiDAR point cloud data: LiDAR point clouds for the GEM inventory plots across SAFE, Maliau Conservation Area and Danum Valley in Malaysian Borneo. The georeferenced point clouds were produced following a survey by the Natural Environment Research Council Airborne Research Facility in 2014, noise points were removed and ground points classified using Lastools. Digital terrain models (DTM) were produced from classified ground points at 10 m resolution. Point clouds were normalised (through ground subtraction) to produce point heights relative to the local ground elevation.

Crown surveys: In each plot, the positions and heights of all trees with a stem diameter at breast height (DBH) ≥ 10 cm were mapped using ground-based Field-Map technology (IFER, Ltd., Jílové u Prahy, Czech Republic) in 2016. We mapped individual tree crowns by measuring 5-30 spatial positions, representing the boundary of a crown projected onto the horizontal plane. Crown projections were smoothed using the "smooth contour line" feature of Field-Map software v.11.

Small stem inventories: At SAFE and Maliau Basin, DBH was measured for all stems >2 cm for 4-5 of the subplots in each GEM plot in 2012-2013 (in the manuscript, we used the average stem size distributions to estimate canopy volume contributions for the un-surveyed subplots). At the Danum Valley sites, DBH was measured for all subplots in a stem census comprising all stems >1 cm in 2011=2012 (DAN-04) and 2013-2014 (DAN-05), as part of the ForestGEO 50 ha inventory plot. Full data from Danum Valley is available, subject to conditions of usage, from the ForestGEO data portal: http://ctfs.si.edu/datarequest/.