研究目的
The objective of this study was to estimate which features derived from ALS data were important for describing trees genera from a riparian deciduous forest, and provide results of classi?cations using two Machine Learning algorithms.
研究成果
The study concluded that 3D ALS data is useful for trees classification over a riparian deciduous forest. The features selection using a stepwise method selected pertinent features for the subsequent SVM and RF classifications, with Alder, Poplar, and Willow being accurately identified. The results can be used as a benchmark for further improvements in such environments, notably for areas with a large number of genera.
研究不足
The study faced limitations such as the difficulty of accessing riparian forest areas for ground observations, the manual delineation of trees crowns which may introduce errors, and the use of data from different flight altitudes which may affect the consistency of the data.
1:Experimental Design and Method Selection:
The study used ALS data from two surveys, in the summer and winter, to classify trees in a riparian deciduous forest. Trees crowns were extracted and global morphology and internal structure features were computed from the 3D points clouds. Five datasets were established, each containing an increasing number of genera to assess the level of discrimination between trees genera.
2:Sample Selection and Data Sources:
191 trees distributed in eight genera located along the Sélune river in Normandy, northern France, were used. ALS data from two surveys, in the summer and winter, were used.
3:List of Experimental Equipment and Materials:
A Teledyne Optech Titan bi-spectral Light Detection and Ranging (LiDAR) sensor with Near Infra-Red (1064 nm) and Green (532 nm) laser beams embedded was used for data acquisition.
4:Experimental Procedures and Operational Workflow:
ALS data pre-processing included the generation of georeferenced and spatially consistent 3D point clouds, classification of ground and above-ground points, and normalization of elevations. Trees were manually extracted from the Canopy Height Models (CHM), and features describing the global morphology and internal structure of trees were computed.
5:Data Analysis Methods:
The most discriminant features were selected using a stepwise Quadratic Discriminant Analysis (sQDA) and Random Forest. The selected features were used for classification using Support Vector Machine (SVM) and Random Forest (RF) algorithms.
独家科研数据包,助您复现前沿成果,加速创新突破
获取完整内容