Nipaporn Chusrinuan, Charlchai Tanavud, and Chao Yongchalermchai

pp. 237 - 245

Abstract

       Songkhla Province is located on the eastern coast of the southern Thai Peninsula, bordering the Gulf of Thailand for approximately 107 km. Most of the basin’s foreshores have been extensively developed for housing, tourism and shrimp farming. The beaches are under deteriorating impacts, often causing sediment transport which leads to an unnaturally high
erosion rate. This natural phenomenon is considered to be a critical problem in the coastal areas affected by the hazard of coastal infrastructure and reduced beach esthetics for recreation. In this study, shoreline changes were compared between 1975 and 2006 using aerial photographs and Landsat imageries using Geographic Information System (GIS). The results
revealed that 18.5 km² of the coastal areas were altered during the period. Of this, 17.3 km² suffered erosion and 1.2 km² were subjected to accretion. The most significant changes occurred between 1975-2006. Shoreline erosion was found at Ban Paktrae, Ranot District, with an average erosion rate of 5.3 m/year, while accretion occurred at Laem Samila, Muang
Songkhla District with an average accretion rate of 2.04 m/year. The occurrences of shoreline erosion have contributed to the degradation of coastal soil and water quality, destruction of beach and mangrove forests, loss of human settlements and livelihood.
        These processes have led to deterioration of the quality of life of the residents. Prevention and mitigation measures to lessen economic and social impacts due to shoreline erosion are discussed