Satellite Images for Detection of Coastal Landuse and Coastline Change in Mueang Prachuap Khiri Khan District, Thailand during 1987-2009

Abstract

Satellite images were used to classify and annotate coastal landuse in Ko Lak and Klongwan subdistricts and to detect changes to the coastline in Ao Noi, Prachuap Khiri Khan, Ko Lak and Klongwan subdistricts, Prachuap Khiri Khan district in Prachuap Khiri Khan province, Thailand. The study used a remotely sensed dataset of LANDSAT-5 TM images with a spatial resolution of 30 × 30 m acquired during 1987–2009. Areas of coastal landuse and coastline changes were calculated using a pixel-based technique. Eight categories of coastal landuse were identifi ed: 1) agriculture, 2) urban and buildings, 3) mangroves, 4) bare soil, 5) airport, 6) seascape, 7) upland forest and island vegetation, and 8) aquaculture and water bodies. The results found that between 1987 and 2009, areas classifi ed as agriculture, urban and buildings, and mangroves increased by 1,150, 360, and 340 rai (1 rai = 0.16 ha) respectively, while aquaculture and water bodies decreased by 1,850 rai. Moreover, there were changes to the coastline in Ao Noi, Prachuap Khiri Khan, Ko Lak and Klongwan subdistricts based on a mixture of stable and eroded features. Comparing 2009 with 2004, the coastline area in Prachuap Khiri Khan, Ko Lak and Klongwan subdistricts had eroded by 31, 40, and 11 rai, respectively.