Abstract:
The objective of this study is to locate the boundaries between Central Thai and Central-Southern Thai hybrid dialect, and between the Central-Southern Thai hybrid dialect and Southern Thai based on tone. The social variable studied is age-group. The findings will help identify the location of the transition area between Central Thai and Southern Thai and show whether the boundaries have the tendency to move further south. Finally a comparison with the results of similar studies on lexical boundaries will be made. Data in this study were collected in the area covering 15 Amphoes from Amphoe Thap Sakae to Amphoe Bang Saphan Noi in Changwat Prachuap Khiri Khan, every Amphoe in Changwat Chumphon from Amphoe Pathio to Amphoe Lamae, and every Amphoe in Changwat Ranong from Amphoe Kra Buri to Amphoe Kapoe. One study location was selected to represent each Amphoe. Two age-groups are involved: the older group (10-20 years old). Two analogous sets consisting of 15 words were selected as test words. Ten tokens of each word were included in the world list giving the total number of 150 words. Language boundaries are located in this study on the basis of the patterns of tone split and tone merge in column A and B that distinguish Central Thai, Central-Southern Thai hybrid dialect, and Southern Thai. In this study the boundary between Amphoe Thap Sakae and Amphoe Bang Saphan, Changwat Prachuap Kiri Khan. In the younger group it is located at Amphoe Bang Saphan, Changwat Prachuap Khiri Khan. As for the boundary between the Central Thai-Southern Thai hybrid dialect and Southern Thai on the eastern coast, it is located between Amphoe Mueang and Amphoe Sawi, Changwat Chumphon. On the western coast, the same boundary is located further south at Amphoe Mueang, Changwat Ranong in the older group, and between Amphoe Mueang and Amphoe Kapoe, Changwat Ranong in the younger group. This study shows that age-group influences tonal variation. When comparing the phonetic characteristics of every tone among the Central-Southern Thai hybrid dialect, Central Thai, and Southern Thai, it is found that the phonetic characteristics of tones in the Central-Southern Thai hybrid dialect are more similar to those of Southern Thai than Central Thai.Chulalongkorn University, 2006.