Beach Profile Assessment and Erosion Rate Estimation of Monsoonal Coastline Area in Pahang, Malaysia

Abstract

Malaysia has a long coastline stretching over 4,809 km where more than 1,300 km of beaches are experiencing erosion. Coastal erosion is defined as the permanent loss of land and habitats along the coastline resulting in changes to the coast. Thus, it is important to detect and monitor coastline changes especially in Pahang, Malaysia. This study used temporal data and high spatial resolution imagery of SPOT 5. It also explored remote sensing and GIS techniques to monitor coastline changes along 10 identified locations, from Cherating to Pekan of the Pahang coast. Ten significant coastline locations namely Pantai Cherating, Pantai Air Balok, Sungai Ular, Pantai Batu Hitam, Pantai Beserah, Swiss Garden Kuantan, Taman Gelora, Pantai Sepat, Pantai Cherok Palok, and Pantai Tanjung Agas were identified to be vulnerable to coastline erosion. Two temporal remote sensed date of SPOT 5 for the year of 2006 and 2014 were used to quantify erosion or accretion rate using National Coastal Erosion Study (NCES) guidelines. The research found that eight area out of 196 or 39.7% locations were eroded and categorized into acceptable erosion category (K3), while 64 area or 32.7 % had significant erosion category (K2) where the coastline retreated more than one meter per year and the most critical eroded area was K1 at 54 or 27.6% sites. Cherating, Swiss Garden Resort, and Cherok Paloh were among the sites with the highest erosion rate between −5.692 and −6.919 m/yr. Meanwhile, the highest rate of accretion or sedimentation was indicated in Tanjung Agas at 7.391 m/yr. A qualitative relationship between the erosion rate and slope percentage for the entire Kuantan coast that stretch from Pantai Cherating to Tanjung Agas, Pekan indicated that the coastal slope percentage, the beach width, and the beach material that deposited on the sites were interrelated and had significant impacts on the erosion rate on several particular zones of the Kuantan coastlines. The findings from monitoring coastline changes and identifying vulnerable erosion areas might be useful in the policy and decision making for sustainable coastal management.