Integration of LiDAR and QuickBird imagery for mapping riparian zones in Australian tropical savannas.

Abstract

Riparian zones are exposed to increasing pressures because of disturbance from agricultural and urban expansion and overgrazing. Accurate and cost-effective mapping of riparian environments is important for managing their functions associated with water quality, biodiversity, and wildlife habitats. The objective of this research was to integrate Light Detection and Ranging (LiDAR) and high spatial resolution QuickBird-2 imagery to estimate riparian zone attributes. A digital terrain model (DTM), a tree canopy model (TCM) and a plant projective cover (PPC) map were first obtained from the LiDAR data. The LiDAR-derived products and the QuickBird bands were then combined in an object-oriented approach to map riparian vegetation, streambed, vegetation overhang, bare ground, woodlands and rangelands. These products were also used to assess the riparian zone width. The overall result was a combined method, taking advantage of both optical and airborne laser systems, for mapping riparian forest structural parameters and riparian zone dimensions. This work shows the accuracy able to be obtained by integrating LiDAR data with high spatial resolution optical imagery to provide more detailed information for riparian zone management