Analysis of Vegetation Density Changes on Coastline Changes in the Glagah Coastal Area, Kulon Progo Regency 2018 and 2023

Abstract

Abstract The construction of Yogyakarta International Airport, which is only 400 meters from Glagah Beach, means that the Kulon Progo Regency Government must pay more attention to guarding the coastline, so that abrasion does not reach Yogyakarta International Airport and the surrounding settlements. The objectives of this research are (1) to identify changes in vegetation density, (2) to identify changes in coastlines, (3) to analyze the relationship between the two in the Glagah Coastal Area, Kulon Progo Regency in 2018 and 2023. The method used in this research is integration between remote sensing and geographic information systems. Remote sensing is used to obtain the Normalized Difference Vegetation Index (NDVI), while the geographic information system is used to analyze shoreline changes using Digital Shoreline Analysis System (DSAS) tools. Based on the 2018 NDVI values, it is known that the area of non-vegetation is 28.2 Ha, low vegetation is 35.2 Ha, medium vegetation is 22.2 Ha, and high vegetation is 26 Ha. The area of each ndvi class in 2023, namely non-vegetation 20.3 Ha, low vegetation 38.2 Ha, medium vegetation 37.9 Ha, and high vegetation 17.7 Ha. The largest amount of abrasion along the Glagah coastline occurred in Sindutan Urban Village, reaching - 56.43 meters and the largest accretion occurred in Jangkaran Urban Village, reaching 65.64 meters. The results of linear regression (0.256) and F test (0.172) show that there is no influence between changes in vegetation density on changes in coastlines in the Glagah coastal area. Even though the results show there is no correlation between vegetation density and changes in coastlines, the role of vegetation is very important in preventing abrasion.