In Taiwan, watershed conservation and management aims to solve problems involving sediment-related disasters. To identify
the distribution of sediment sources and the amount of unstable deposit, long-term geomorphologic monitoring has been implemented
and countermeasure plans have been progressively executed. LiDAR (Light Detection and Ranging) is a state of the art
technology, which is generally used to create the high-precision DEM. airborne and Ground-Based LiDAR have been utilized to
precisely scan and measure topological changes. Though, the precision of ground-based LiDAR is higher than airborne, there are
limitations to the area that can be scanned in one instance. On the contrary, airborne LiDAR can quickly complete high density
scanning to obtain the 3-dimensional data of a target, which can be applied directly to analyzing sediment-related disasters and
effectiveness of conservation management in a watershed scale. Taking this into account, this study utilizes multi-period DEMs
created by airborne LiDAR and uses ground-based LiDAR to assess DEM accuracy. The DEM is used to estimate amount of
sediment trapped within check dams and deposited on hillslopes. Furthermore, the obtained results can be employed as a reference
for remediation measures such as dredging and sediment removal when necessary, and for future watershed conservation
and management.
