An acoustic study of contextual tonal variation in Tianjin Mandarin

The f0 realization of lexical tones is known to vary greatly due to contextual tonal variation processes such as tone sandhi and tonal coarticulation. This study set out to investigate the f0 variability induced by these two different sources with well-controlled acoustic data from Tianjin Mandarin. Tianjin Mandarin is known for its complex patterns of tonal variation over disyllabic constituents, as well as for the conflicting directionality of sandhi alternations and possible iterative application of disyllabic sandhi rules over trisyllabic constituents. Previous studies on Tianjin tone sandhi have often been based on impressionistic descriptions of speech produced by speakers of older generations. In this study, we investigated the f0 realization of disyllabic and trisyllabic tonal sequences in Tianjin Mandarin produced by younger speakers (born in the 1980s). Through examining f0 variation of lexical tones as a function of different following tones, we observed an interesting anticipatory raising effect of the lexical low-falling tone (T1). Furthermore, we confirmed three tonal sequences with tone sandhi changes: (1) two low-falling tones (T1T1), (2) a high-falling tone followed by a low-falling tone (T4T1), and (3) two low-dipping tones (T3T3). These disyllabic tone sandhi patterns, however, were not consistently observed within trisyllabic sequences, as claimed in the literature. Specifically, while T3T3 showed sandhi application regardless of its position within a trisyllabic sequence, T1T1 and T4T1 sequences showed sandhi changes only when they were right aligned. Last but not least, no tonal neutralization was observed over any of the sandhi processes. Rather, we argue that T3T3 is a near-merger sandhi case, while T1T1 and T4T1 can be classified as no-merger sandhi sequences.