The use of dual-wavelength airborne laser scanning for estimating tree species composition and species-specific stem volumes in a boreal forest

The estimation of species composition and species-specific stem volumes are critical components many forest inventories. use airborne laser scanning with multiple spectral channels may prove instrumental for the cost-efficient retrieval these variables. In this study, we scanned a boreal using two channels: 532 nm (green) 1064 (near infrared). data was used in two-step methodology to (1) classify species, (2) estimate volume at level individual tree crowns. classification pines, spruces broadleaves involved linear discriminant analysis (LDA) resulted an overall accuracy 91.1 % trees. For volume, employed k-nearest neighbors models evaluated performance plot 256 field plots located central Sweden. This root-mean-square errors (RMSE) 36 m3/ha (16 %) total 40 (27 pine 32 (48 spruce 13 (87 broadleaf volume. We also simulated monospectral near infrared (NIR) scanner by excluding features based on green channel. lower (86.8 RMSE 41 (18 largest difference when only NIR channel difficulty accurately identify When channel, broadleaved increased from 26 m3/ha. study thus demonstrates added benefit both volumes. addition, investigated how height influences results where shorter trees were found be more difficult correctly.