Digital Elevation Model Differencing and Error Estimation from Multiple Sources: A Case Study from the Meiyuan Shan Landslide in Taiwan

Abstract

In this study, six different periods of digital terrain model (DTM) data obtained from various flight vehicles by using the techniques of aerial photogrammetry, airborne LiDAR (ALS), and unmanned aerial vehicles (UAV) were adopted to discuss the errors and applications of these techniques. Error estimation provides critical information for DTM data users. This study conducted error estimation from the perspective of general users for mountain/forest areas with poor traffic accessibility using limited information, including error reports obtained from the data generation process and comparison errors of terrain elevations. Our results suggested that the precision of the DTM data generated in this work using different aircrafts and generation techniques is suitable for landslide analysis. Especially in mountainous and densely vegetated areas, data generated by ALS can be used as a benchmark to solve the problem of insufficient control points. Based on DEM differencing of multiple periods, this study suggests that sediment delivery rate decreased each year and was affected by heavy rainfall during each period for the Meiyuan Shan landslide area. Multi-period aerial photogrammetry and ALS can be effectively applied after the landslide disaster for monitoring the terrain changes of the downstream river channel and their potential impacts.

Geomorphological evolution of landslides near an active normal fault in northern Taiwan, as revealed by lidar and unmanned aircraft system data

“…Consequently, quantitative studies have been successfully conducted for delineating landslides; determining risks (Gritzner et al, 2001), landslide morphology (Glenn et al, 2006;Staley et al, 2006;Santangelo et al, 2015b), and activity Chang et al, 2006); estimating cut-and-fill volumes Chen et al, 2006;Chan et al, 2012;Hsieh et al, 2016); and performing geological mapping (Yeh et al, 2014). In this study, an Optech ALTM3070 apparatus was used to record the positions of the laser reflecting points with a rate of up to 71 000 pulses per second when we conducted the Central Geological Survey project in 2005.…”

“…The cut-and-fill volumes of a landslide can be estimated using two digital terrain models (DTMs): one before the landslide and one thereafter Chen et al, 2006;Chan et al, 2012;Hsieh et al, 2016). The information derived using the DTMs can facilitate the identification and estimation of landslide activity and evolution.…”

Direct Measurements of Bedrock Incision Rates on the Surface of a Large Dip-slope Landslide by Multi-Period Airborne Laser Scanning DEMs

“…The values obtained in each line are used to draw the profile, so the profile lines of the maximum value, minimum value, mean, and standard deviation within the rectangle [55,56] are obtained. This study selected irregular areas along the gullies to draw the swath profiles [11]. As described above, the DEM data within the irregular areas were rotated to make one side of the profiles be parallel to the south-north direction.…”

“…In particular, multi-temporal DEMs [10][11][12][13] can be directly used for monitoring and analyzing the terrain change. Moreover, the erosion of the ground surface will create geomorphological relief and interact with the climate correlated to human activity [14].…”

Earth Observations for Geohazards: Present and Future Challenges

“…Fernández et al [26] use Unmanned Aerial Vehicles imagery and high resolution photogrammetry to monitor horizontal and vertical displacements of a landslide affecting olive groves in La Guardia de Jaén (Spain). Finally, in Hsieh et al [27], the errors of digital terrain models (DTMs) derived using different techniques are discussed.…”