Spatio-temporal analysis of wulan delta in Indonesia: Characteristics, evolution, and controlling factors

The evolution of the Wulan Delta began after the construction of the Wulan River Canal in 1892. It alters the shoreline erosion and accretion that affect the land dynamics of the coastal area. This study aims to analyze the spatio-temporal evolution of the Wulan Delta, including the shoreline and its dynamics, as well as the geomorphological processes that affect it. The shoreline change was extracted digitally from Landsat satellite images and divided into four periods, i.e., 1995-2000, 2000-2011, 20112015, and 2015-2020. We used the histogram thresholding method to separate the land from the sea and produce the shoreline as the interface. This research employed field check and focus group discussion for identifying the cause and impact of shoreline dynamics in the research area. The results show that land loss and accumulation over 25 years (1995-2020) are-7.16 km2 and +6.58 km2, respectively. In Wulan Delta, the erosion is due to high waves and sedimentation due to mangrove planting and high sediment from the rivers. The development rates of the Wulan Delta for the period of 1995-2020 were 73,200 m2/year. © 2021, Asociatia Geographia Technica. All rights reserved.