Terrestrial laser scanner (TLS) and destructive measurements in short-rotation woody crops (SRWCs) in NE of Romania

The data are obtained from hybrid poplar crops installed in NE Romania, managed in short rotation (SRWCs) between 5, 6, and 7 growing seasons. Planted every spring, outside the growing season, at a depth of 0.6 m in the ground with two clones: AF8 and Pannonia. Rods (2 m long cuttings) were used as planting material for a density of 1667 trees/ha (3 x 2 m). For the estimation of volume and biomass, scans and gravimetric measurements were performed on tree component parts (trunk/stem and branches). Scanning of the sample areas (3 x 10 trees for each variant) was carried out using the Z+F Imager 5010. The scanning period was outside the growing seasons. The destructive (gravimetric) method of estimating biomass involves weighing the trees (184 in total) by component parts: trunk and branches (10 g accuracy). The moisture content of the components was determined by drying the samples (wood discs and branches) at a temperature of 105 °C to a constant mass. The QSM Model in MatLab was used for tree volume reconstruction. Where d is the diameter (cm) - measured at the base and at 1 m height, h (m) is the total height - measured after harvesting by roulette and by QSM reconstruction (after TLS scan). B (kg) is the dry mass of the whole tree (tot = branches + stem) and stem, and V (litres/ dm3) is the tree volume (tot) for the whole tree and stem. Branch weight results by difference for both variables.