Vegetation classification of the riparian zone along the Brisbane River, Queensland, Australia, using light detection and ranging (lidar) data and forward looking digital video

Light detection and ranging (lidar) technology has the ability to provide accurate height and positional data. This is of particular relevance to the riparian zone where the vegetation is often narrow and difficult to assess using conventional means such as aerial photography. Height has been widely used as one of the structural attributes for classifying vegetation. In particular, the Specht classification system has proven useful in classifying and naming forest and other vegetation types within Australia. Specht uses as primary attributes the height and the foliage projective cover of the tallest stratum to classify vegetation into structural types. A technique, which is replicable and objective, has been developed that automates the clustering of tree heights obtained from lidar into the Specht structural vegetation types to produce a map of vegetation height classes at 1:4000 scale. While the laser data can be used to produce detailed maps of height, it is still necessary to manually interpret imagery to allocate canopy cover and species composition to the mapped polygons. Forward looking high resolution digital video taken from a helicopter has proven to be a cost effective form of imagery compared with alternatives such as aerial photography.