Spatial Modeling of Coastline Change for Two Decades (1994-2014) in Pangandaran, West Java - Indonesia

Coastal areas are very vulnerable to various pressures, developments, and changes. In the last three decades, due to the process of abrasion and accretion, there have been changes in coastlines in various coastal areas in Indonesia. Coastal abrasion and accretion are major concerns in coastal management. Morphological changes have had a major impact on land use and the socio-economic development of communities in coastal areas. In connection with this issue, it is necessary to conduct a study that aims to determine the rate and location of coastline changes in Pangandaran Regency. Considering that Pangandaran Regency is one of the southern regions of Java which is directly facing the Indian Ocean it has high coastal dynamics. In addition, Pangandaran beach is a beach tourism destination that is quite well known and has the potential to be developed, but in some locations, there are indications of a significant decline in the coastline. In this study, Landsat satellite images in time series (1994-2014) were analyzed using remote sensing technology and GIS approaches. Analysis of coastline change was carried out using the DSAS program. The results of the study show that the coastline change in Pangandran is dominated by abrasion at a rate of about -2.5 to -0.1 meters/year. The rate of change of the Pangandaran coastline which experienced the highest abrasion was -4.7 meters/year and the lowest was -0.1 meters/year, while the highest accretion rate was 40.1 meters/year and the lowest was 0.1 meters/year. Maximum abrasion is located at Sukaresik village (Sidamulih Sub-district) at the mouth of the Karang Tirta River. The minimum abrasion is located at Pananjung village. Meanwhile, accretion occurred in several villages such as Pananjung Village, Wonoharjo Village (Pangandaran Sub-district), Balogo Village (Kalipucang Sub-district), Kerta Mukti Village (Cimerak Sub-district), and Cikambulan Village (Sidamulih Sub-district). Minimum accretion is located at Pananjung village and maximum accretion is located at Bagolo village near the estuary of Citanduy River.