Monitoring and Analysis of Landslide Hazard Using Dinsar Technique Applied to Alos Palsar Imagery: A Case Study in Kayangan Catchment Area, Yogyakarta, Indonesia

Abstract

Abstract:The differential synthetic aperture radar interferometry (DInSAR) technique is applied to the ALOS PALSAR data to observe surface displacement in Kayangan catchment area, Yogyakarta, Indonesia. Change detection is implemented to extract information on several landslides that occurred in the region in a time span between 2007 and 2009. The advanced DInSAR processing of images (2007)(2008)(2009)) has shown slight surface movements before the landslide events. These results are compared and validated with available GPS measurements. Our analysis reveals that Kayangan catchment area exhibits clear indication of surface displacements varying from 5.2 to 57.9 cm/year. The occurence of landslides has been analyzed in relation to the following terrain parameters; elevation, slope, distance to stream network, geology, landuse, and distance from road. Among these factors, it is found that 18% of landslides occur in elevation >100 m, 56% in slope 30-40°, 34% in <25 m distance to stream networks, 100% in kebobutak formation, 67% in mix garden of land use types, and 100% in <25 m distance from road. The landuse is the most influential factor, since there are only four types of landuse that can lead to landslide occurrence, i.e., mixed garden, dryland agriculture, bush, and settlement. The analysis of land deformation is promising for assessing acceleration caused by a destabilizing anthropogenic change, and relationship between seasonal precipitation and deformation variability.

Social vulnerability toward tsunami hazard in the coastal area of Bayah Dome Geopark, in Lebak Regency, Banten Province

“…The high population density illustrates the high probability of loss of life and property hence threatening the community's survival [18]. Very high population densities will be more vulnerable to tsunamis than areas with lower densities because they have a high potential for victims when a tsunami arrives [19]. The Cihara sub-district has the lowest population density in the period 2017-2020, which ranges from 212-221 people km -2 with an average of 215 people km -2 , so this sub-district has the lowest vulnerability.…”

InSAR Monitoring of Landslide Activity in Dominica

“…These attributes, along with the ability to measure changes in phase between acquisitions, have allowed SAR data to be used extensively in the mapping and monitoring of landslides ( [20][21][22][23][24][25][26][27][28][29] and many others). In tropical environments similar to Dominica, SAR data have been shown to be successful in mapping and tracking slow-moving landslides for risk detection and disaster management applications [30][31][32][33].…”

“…Refs. [30,31], for example, applied the Differential Interferometric Synthetic Aperture Radar (DInSAR) technique to satellite SAR data over active landslide areas within Indonesia. Similar to Dominica, Indonesia is a tropical environment vulnerable to landslides due to its mountainous landscape, loose soil, and heavy rainfall.…”

“…Ref. [30] focused their study on a massive rock avalanche induced by significant rainfall, while [31] concentrated on a number of predominantly slow-moving translational and slump slides that occurred in rock layers and unconsolidated materials, respectively. Ref.…”

“…Ref. [30] was able to observe surface displacement prior to the catastrophic slope failure, while [31] was able to identify active landslides and monitor their deformation rates. DInSAR-derived data, such as the detection of deformation prior to massive slope failure, were recommended to be used as an added capability in landslide susceptibility mapping.…”