Contact-Induced Layering and Diffusion in Yuè Chinese Varieties—The *-iun/iut and *-un/ut Merger Reconsidered

Abstract

This study re-investigates the merger of *-iun/iut and *-un/ut in 46 Yuè Chinese varieties, which lacks explanatory treatment, from the variant derivative patterns of *-iun/iut > [yn]/[yt] and *-un/ut > [yn]/[yt]. The historical-comparative method was employed as the frame to analyze spatial (geographic) variation obtained from QGIS. The data showed that the merger of the reflexes of *-iun/iut and *-un/ut does not prevail in the majority of Yuè varieties, while mergers of *-iun/iut with *-in/it and *-iun/iut with *-on/ot or *-ion/iot are dominant. The spatial patterns of *-iun/iut and *-un/ut suggest different diffusion patterns and background factors.

1. Introduction

This paper examines the spatial (geographic) variation patterns of *-iun/iut > [yn]/[yt] and *-un/ut > [yn]/[yt] in Yuè Chinese 粵語.1 In Yuè, the pronunciations of reflexes of *-iun/iut and *-un/ut following alveolar initials are complex.2 For example, the main vowel of the reflexes is mainly [œ] for *-iun/iut and [y] for *-un/ut in Guǎngzhōu Yuè 廣州粵語 (with some exceptions), which generally retained the rounded features and the distinction between *-iun/iut and *-un/ut that are seen in the reconstructed ancestral forms. Far to the west in Nánníng 南寧, the main vowel of the reflexes of *-un/ut is mainly [y], that of *-iun/iut is either [y] or [ɐ] depending on the correspondence set, but sometimes even co-existing as two variants for a single reflex. For instance, *tshun¹ “村” ‘village’ and *chiun¹ “春” ‘spring’ are [tsʰyn¹] and [tsʻœn¹], respectively, in Guǎngzhōu Yuè, while they are [tsʰyn¹] and [tsʰɐn¹]/[tsʰyn¹] in Nánníng Yuè. However, in other Yuè varieties, the main vowel [ɐ] is predominant in the reflexes. The rise and spread of [y] among forms with [ɐ] is of great significance.

In the Qièyùn 切韻 phonological system represented in the Qièyùn rime dictionary compiled in 601 CE and its successors, *-iun/iut and *-un/ut were assigned to the Zhēnshè Hékǒu 臻攝合口 rime group, due to their shared combination of dental coda and rounded main vowel. The former was sorted into Zhēnshè hékǒu division III while the latter was assigned to Zhēnshè hékǒu division I on the basis of the difference in rime onset (medial). Given that the Qièyùn system is generally cited to explain contemporary changes in Chinese dialects, previous studies simply note that the Zhēnshè hékǒu division III had lost the medial and thus Zhēnshè Hékǒu rime divisions have merged together in the specific Yuè varieties affected by the change, such as Liánzhōu 廉州 (Zhang 2012), Xīnhùi 新會 (Tang 2004), Dōngguǎn 東莞 (Li 2010) and Nánníng (Lin and Qin 2008). Some studies also state that Zhēnshè Hékǒu rimes have lost the rounded feature and merged with Zhēnshè kāikǒu 臻攝開口 (*-en/et, *-in/it), which is the corresponding rime group of Zhēnshè Hékǒu with an unrounded main vowel, for example in Gāozhoū 高州, Xìnyí 信宜, Liánjiāng 廉江, Wúchuān 吳川, Zhànjiāng 湛江 and Yángjiāng 陽江 (Weng 2012), with similar observation also recorded for Zēngchéng 增城 (Liang 2016), Yángchūn 陽春 (Weng 2012; Liu 2019) and Hèzhoū 賀州 (Wei 2019). However, these are merely descriptions of the matter and not explanations or detailed studies. Therefore, this study re-examines the merger of *-iun/iut and *-un/ut from the variant patterns of *-iun/iut > [yn]/[yt] and *-un/ut > [yn]/[yt] using a historical-comparative linguistic methodology and a dialect geography-based analysis. This approach reveals that the reflexes of *-iun/iut and *-un/ut are not merged in the vast majority of Yuè varieties and are not inseparable as these two groups of reflexes have different diffusion patterns across the linguistic map. The discussion below focuses on three research questions:

• Is *-iun/iut and *-un/ut a common merger in Yuè Chinese?
• What are the diffusion patterns of *-iun/iut > [yn]/[yt] and *-un/ut > [yn]/[yt] and related merger with other group(s) of reflexes (if any), respectively?
• What are the factors that affect the patterns?

2. Background Regarding Yuè Chinese

As one of the dialect groups of the Sinitic languages in China, Yuè is widely spoken in Guǎngdōng 廣東省 and Guǎngxī Province 廣西省of China, Hong Kong and Macau (Zhan 2004, p. 1). As with other Chinese dialect groups, many studies have approached the classification issue for different Yuè varieties, yet a consensus has not been reached. The Language Atlas of China (Li 1987) categorized Yuè into seven subgroups: Guǎngfǔ 廣府, Sìyì 四邑, Gāoyáng 高陽, Gōulòu 勾漏, Wúhuà 吳化, Yōngxún 邕潯and Qīnlián 欽廉. Yue-Hashimoto (1991) classified it into five major subgroups with four micro-groups, including Guǎngfǔ, Sìyì, Liǎngyáng 兩陽, Běi sānjiǎozhōu 北三角洲 (Nèilù 內陸 & Sānyì Zhàoqìng 三邑肇慶) and Nán sānjiǎozhōu 南三角洲 (Qīnlián & Zhōngshān中山). Zhan et al. (2002) and Zhan (2004) classified Yuè into Guǎngfǔ, Sìyì, Xiāngshān 香山, Gwǎnbǎo 莞寶, Gāoléi 高雷and Guìnán 桂南. Apart from the name of the subgroups, many varieties have different groupings among these three classifications (See

Table 1. Classification of Yuè dialects in the Language Atlas of China (Li 1987); Yue-Hashimoto (1991); Zhan et al. (2002) and Zhan (2004), with date sites selected for this study (underlined) #.

Yuè Varieties (Examples)	Language Atlas of China (Li 1987)	Yue-Hashimoto (1991)	Zhan et al. (2002) and Zhan (2004)
Dōngguǎn and Bǎoān 寶安	Guǎngfǔ	Nán sānjiǎozhōu- Qīnlián	Gwǎnbǎo
Zhōngshān and Zhūhǎi 珠海		Nán sānjiǎozhōu-Zhōngshān	Xiāngshān
Fóshān 佛山, Gāomíng 高明, Shùndé 順德, Nánhǎi 南海, Sānshuǐ 三水, Zhàoqìng, Zhàoqìng (Gāoyào 高要)		Běi sānjiǎozhōu- SānyìZhàoqìng	Guǎngfǔ
Sháoguān 韶關		Běi sānjiǎozhōu- Nèilù
Yúnfú 雲浮, Lèchāng樂昌, Qīngyuǎn 清遠, Fógāng 佛岡, Yīngdé英德, Shēnzhèn 深圳		No data
Guǎngzhōu, Macau, Pānyú 番禺, Huādū花都 *, Cónghuà從化, Zēngchéng		Guǎngfǔ
Nánníng, Guipíng桂平	Yōngxún		Guìnán
Yōngníng邕寧, Héngzhoū 橫州 *		Běi sānjiǎozhōu- Nèilù
Táishān 台山, Jiāngmén 江門, Dǒumén 斗門, Kāipíng開平, Xīnhuì, Ēnpíng 恩平, Hèshān 鶴山	Sìyì	Sìyì	Sìyì
Yángjiāng and Yángchūn	Gāoyáng	Liǎngyáng	Gāoléi
Gāozhoū, Xìnyí		Guǎngfǔ
Sìhuì 四會, Guǎngníng 廣寧, Déqìng 德慶, Fēngkāi封開, Luódìng羅定, Huáijí 懷集, Yángshān 陽山, Liánzhoū 連州 *, Liánshān 連山	Gōulòu	No data	Guǎngfǔ
Guìgǎng 貴港 *			Guìnán
Yùlín 玉林, Běiliú 北流		Běi sānjiǎozhōu- Nèilù
Wúzhoū 梧州	Guǎngfǔ
Huàzhōu 化州, Wúchuān	Wúhuà/Gāoyáng		Gāoléi
Zhànjiāng		No data
Liánjiāng		Nán sānjiǎozhōu- Qīnlián
Liánzhōu 廉州	Qīnlián		Guìnán
Língshān 靈山			Not mentioned

* Huādū, Héngzhoū, Liánzhoū and Guìgǎng previously named as Huāxiàn 花縣, Héngxiàn 橫縣, Liánxiàn 連縣 and Guìxiàn 貴縣, respectively, which were also employed in the three studies. # Qūjiāng (Mǎbà), Xīnxīng and Língmíng were not included in Yue-Hashimoto (1991); Zhan et al. (2002) and Zhan (2004), while in Language Atlas of China, Qūjiāng (Mǎbà) was classified as Guǎngfǔ with Xīnxīng, and Língmíng was grouped as Yōngxún.

).

3. Methods and Materials

3.1. Methods

3.1.1. Historical-Comparative Method

This study employs Common Dialectal Chinese (CDC), a phonological system reconstructed by (Norman 2006, 2011, forthcoming), as the framework for the historical-comparative analysis. Unlike the works of Karlgren (1940), Pulleyblank (1984), Baxter and Sagart (2014)3 as well as Proto-Yue of McCoy (1966), which heavily relied on Qièyùn or its successors for reconstruction, thus maintaining non-phonemic differences in their system, CDC was developed on the basis of a comparative treatment of the phonological systems of contemporary Chinese dialects with the Qièyùn primarily as a supplement only.4 It adjusted the categories of Qièyùn with reference to modern dialects, excluding the Mǐn dialects 閩語 (Norman 2006). Therefore, CDC is more powerful in reflecting the actual common phonological system of the dialects as well as their differing phonological developments.

3.1.2. Dialect Geography

Dialect geography, also known as dialectology, is the study of the geographical patterns of dialects or language variations on linguistic maps, considering the evidence not only in geographic perspective but also in economic, political and social cultural perspectives (Chambers and Trudgill 1998, p. 14; Lauder 2006 as cited in Saddhono and Hartanto 2021). There are two types of linguistic maps used in dialect geography, namely display maps and interpretive maps. The former simply lists the results obtained from interviews onto a map, while the latter is developed based on primary sources together with comparative representation (Chambers and Trudgill 1998, pp. 25–27). Although display maps can be seen in various studies on Sinitic dialects, such as Linguistic Atlas of Chinese Dialects (Cao 2008), the use of interpretive maps with dialect geography-based analysis has not been widely adopted in the field of Sinitic dialectology.

For the purpose of visualizing the spatial variations in linguistic data and developing interpretive maps, this study makes use of QGIS (QGIS Development Team 2023). The base map of the maps is Open Street Map available in the QGIS’s plugin “QuickMapServices”. Unless otherwise specified, the syllables selected for map production are commonly spoken colloquial words.

3.2. Materials

3.2.1. Data Source and Sites

The dataset of this study includes 46 Yuè varieties (Supplementary Material). Sites with [yn]/[yt] in the reflexes of either *-iun/iut or *-un/ut or both were selected from A Survey of Dialects in the Pearl River Delta (Zhan and Cheung 1987), A Survey of Yue Dialects in North Guangdong (Zhan and Cheung 1994), Guǎngxī Tōngzhì: Hànyǔ Fāngyánzhì 广西通志•汉语方言志 [Compilation of Chinese Dialects in Chronicles of Guangxi] (Guangxi Local Records Compilation Committee 1998), A Survey of Yue Dialects in West Guangdong (Zhan and Cheung 1998) and Guǎngxī Hànyǔ Fāngyán Yánjiū 广西汉语方言研究 [A Study on Chinese Dialects in Guangxi] (Xie 2007). Thereby, the dataset of this study included Guǎngzhōu (Urban), Macau (Urban), Pānyú (Shìqiáo 市橋), Huādū (Huāshān 花山), Cónghuà (Urban), Fóshān (Urban), Nánhǎi (Shātóu 沙頭), Shùndé (Dàliáng 大良), Sānshuǐ (Xīnán 西南), Gāomíng (Míngchéng 明城), Zhōngshān (Shíqí 石岐), Zhūhǎi (Qiánshān 前山), Qīngyuǎn, Fógāng, Yīngdé (Hánguāng 浛洸), Yángshān, Liánzhōu 連州 (Qīngshuǐ 清水), Sháoguān, Qūjiāng (Mǎbà) 曲江 (馬壩), Lèchāng, Nánníng, Yùlín, Wúzhoū, Zhàoqìng (Gāoyào), Sìhuì, Guǎngníng, Huáijí, Fēngkāi (Nánfēng 南豐), Yúnfú (Yúnchéng 雲城), Xīnxīng 新興, Luódìng, Guipíng (County seat), Héngzhōu (County seat), Guìgǎng (Nánjiāng 南江), Běiliú (Tángliáo 唐僚), Língshān (County seat) and Língmíng (County seat).5 Dōngguǎn (Guǎnchéng 莞城), Táishān (Táichéng 台城), Kāipíng (Chìkǎn 赤坎), Ēnpíng (Niújiāng 牛江) and Liánzhōu 廉州 were also taken into the dataset to cover more Yuè subgroups and facilitate spatial distribution analysis of *-un/ut or *-iun/iut, although [yn]/[yt] are not reflected in the reflexes of these two groups in these sites. For the same reasons, Huàzhōu (Xiàjiāng 下江), Yángjiāng, Yángchūn (Hékǒu 河口) and Xìnyí were chosen as well from Huàzhōu Yuèyǔ Gàishuō 化州粤语概说 [An outline of Huazhou Yue] (Li 1996), Study of Yangjiang Dialect in Guangdong Province China (Huang 2018), The Phonological Study on Yue Dialect of Hekou in Yangchun City (Liu 2019) and Xìnyí Fāngyánzhì 信宜方言志 [Compilation of Chinese Dialects in Xinyi] (Luo and Ye 1987). All 46 data sites as well as their given classification are shown in Table 1 (underlined).

The geographic location of the sites is provided in Figure 1. According to the Language Atlas of China (Li 1987), Lèchāng, Sháoguān and Qūjiāng are Yuè exclaves surrounded by Hakka Chinese, additionally Língmíng and Liánzhōu, two other exclaves, are encircled by Zhuang languages and lu Mien languages, respectively. Nánníng, Guìgǎng, Guipíng, Huáijí, Yángshān, Liánzhōu, Fógāng and Dōngguǎn are located in the boundary of Yuè. North or northwest of Nánníng, Héngzhoū, Guìgǎng, Guipíng and Huáijí are within the domain of Southwestern Mandarin and Hakka. Finally, Yángshān, Liánzhōu, Fógāng and Dōngguǎn are adjacent to Hakka.

3.2.2. Data Selection

The reflexes of *-iun/iut and *-un/ut following alveolar affricates, fricatives and an approximant in CDC (*ts-, *tsh-, *dz-, *c-, *ch-, *j-, *s-, *z-, *sh-, *zh-, *l-) comprise the dataset of this study. This selection of initials is consistent with the environment of *-iun/iut which only occurs with alveolar affricates, fricatives and approximants. This selection is also congruent with the restricted environment of *-iun/iut, *-un/ut > [yn]/[yt], as it is a conditioned sound change that is not observed following labial consonants (

Table 2. Examples of the reflexes of *-un/ut following labial and alveolar consonants.

Sites	*phun1/phun5 “噴” ‘spray’	*tshun5 “寸” ‘inch’
Guǎngzhōu	pʰɐn5	tsʰyn5
Zhōngshān	pʰɐn5	tsʰyn5
Yùlín	pʰan5	tʰyn5
Nánníng	pʰɐn5	tsʰyn5

).

3.3. Representation of Data

Unless otherwise specified, the International Phonetic Alphabet (IPA) presented in the data of this study is the same as stated in the data sources, for example [œ] of Guǎngzhōu Yuè is maintained as the transcription of Zhan and Cheung (1987), although it is probably [ɵ] preceding [-n] or [-t], same as Hong Kong, as stated in the Handbook of the International Phonetic Association (The International Phonetic Association 1999, p. 59). Additionally, the aspiration “ ʻ “ employed in the data sources is transcribed as “ ʰ “ in this study.

Tones are denoted by a numerical system (

Table 3. Numerical system of tonal representation.

Number	Tone
1	Yīnpíng 陰平
2	Yángpíng 陽平
3	Yīnshǎng 陰上
4	Yángshǎng 陽上
5	Yīnqù 陰去
6	Yángqù 陽去
7	Yīnrù
8	Yángrù

) that is commonly used in Chinese dialectology and is also adopted by CDC. In addition to the eight tones of common Chinese phonology, this study also distinguishes upper Yīnrù 陰入 = 7A, lower Yīnrù = 7B, upper Yángrù 陽入 = 8A, lower Yángrù = 8B.

4. Results and Discussion

4.1. Merger of *-iun/iut and *-un/ut in Yuè Chinese

Figure 2 presents the merger or contrast of *-iun/iut and *-un/ut in Yuè using *tshun¹ “村” ‘village’ and *chiun¹ “春” ‘spring’ as an example. Although *tsh- has merged with *ch- in many Yuè varieties, *tshun¹ and *chiun¹ retain the contrast not only in the sites which have [yn]/[yt] in the reflexes of *-un/ut or *-iun/iut, but indeed in the majority of the varieties. With the exception of Fēngkāi and Kāipíng, it seems that the merger of *-iun/iut and *-un/ut happens randomly in Yuè. However, if the pronunciations of *tshun¹ “村” and *chiun¹ “春” are closely examined (

Table 4. Pronunciations of “村” and “春” in the data sites (examples).

Sites	*tshun1 “村” ‘village’	*chiun1 “春” ‘spring’
Guǎngzhōu	tsʰyn1	tsʰœn1
Huàzhōu	tʰin1	tʃʰɐn1
Yángjiāng	tʃʰun1	tʃʰɐn1
Nánníng	tsʰyn1	tsʰɐn1/ tsʰyn1
Yùlín	tʰyn1	tɕʰan1
Liánzhōu 廉州	tʃʰun1	tʃʰɐn1
Héngzhoū	tʃʰun1	tʃʰɐn1
Xìnyí	tsʰyn1	tsʰɐn1
Fēngkāi	tsʰɐn1	tsʰɐn1
Kāipíng	tʰun4	tsʰun1
Táishān	tʰun1	tsʰun1
Ēnpíng	tsʰun5	tsʰun1

), it can be observed that Kāipíng retains the contrast between *tshun¹ and *chiun¹ not by rime but by initials only. A similar situation can be discerned in Táishān and Ēnpíng, which retain the distinction by initials and tone, respectively, but not by rime. Indeed, the change *-iun/iut, *-un/ut > [un]/[ut] occurred in Táishān, Kāipíng and Ēnpíng, varieties under the Sìyì subgroup (

Table 5. Pronunciations of *sun³ “損” and *siun³ “筍” in Kāipíng, Táishān and Ēnpíng.

Sites	*sun3 “損” ’hurt/loss’	*siun3 “筍” ‘bamboo shoots’
Kāipíng	ɬun3	ɬun1
Táishān	ɬun3	ɬun3
Ēnpíng	sun3	sun3

; also see Table 4). Therefore, it is obvious that the merger of *-iun/iut and *-un/ut is not a common characteristic in Yuè Chinese, though it is in the Sìyì subgroup. A separate analysis of *-iun/iut > [yn]/[yt] and *-un/ut > [yn]/[yt] will be made to examine their geographical distributions and diffusion patterns.

4.2. Diffusion Pattern of *-iun/iut > [yn]/[yt] and Related Mergers

Before examining the geographical distribution of *-iun/iut > [yn]/[yt], it is worth noting that a correspondence between [œ] and [ɐ] exists regularly in the reflexes of *-iun/iut, despite the presences of a few abnormalities, such as is seen in Guǎngzhōu (

Table 6. Pronunciations of *jiun² “唇” in the data sites (examples).

Sites	*jiun2 “唇” ’Lip’
Guǎngzhōu	sœn2
Huàzhōu	ʃɐn2
Yángjiāng	ʃɐn2
Yùlín	ʃɐn2
Liánzhōu	ʃɐn2
Héngzhoū	ʃɐn2
Xìnyí	sɐn2
Fēngkāi	tsɐn2

). Previous research on this correspondence revealed that [œ] changed to [ɐ] in the majority of Yuè varieties aside from Guǎngzhōu and the adjacent varieties (Sung and Hui 2022). This suggests that reflexes of *-iun/iut have merged with *-en/et and *-in/it in a branch of Yuè varieties.6 Figure 3 depicts the merger or contrast between *-iun/iut and *-in/it in *chiut⁷ “出” ‘out’ and *tshit⁷ “七” ‘seven’. Similar to [œ] > [ɐ] in which Guǎngzhōu and the adjacent varieties stand out, Guǎngzhōu and other varieties near the Pearl River Delta (such as Macau, Fóshān, Nánhǎi, Shùndé and Sānshuǐ) retained the contrast on the rime between *-iun/iut and *-in/it, as well as the varieties in the north of Guǎngdōng Province (Yīngdé, Sháoguān, Qūjiāng and Lèchāng) and Nánníng. This pattern brings up the two following questions:

• Is there any relationship in the contrast situation between the Pearl River Delta, the north of Guǎngdōng Province and Nánníng?
• If yes, what is/are the factors behind it?

The systematic contrast between *-iun/iut and *-in/it as well as in the rime of “出” in the data sites suggests a relationship between the Pearl River Delta, northern Guǎngdōng and Nánníng (Figure 3 and Figure 4). The morpheme “出” with [yt] is recorded in Nánhǎi, Qīngyuǎn, Lèchāng and far west—Nánníng. In Guǎngzhōu, Lìwān 荔灣 (the rural of old Guǎngzhōu city), Tiānhé Shípái 天河石牌 (the oldest urban village in Guǎngzhōu) and Huángpǔ Luógāng 黃埔蘿崗 (suburban of Guǎngzhōu) additionally have the same circumstance (Project for the Protection of Language Resources of China 2022; Liang 2016). Zhuang (2004, p. 16) pointed out that Guǎngzhōu accent as well as Guǎngfǔ Yuè have prevailed in Sháoguān, Qūjiāng and Lèchāng after World War II, due to the temporary relocation of the Guǎngdōng provincial capital from Guǎngzhōu to Sháoguān during World War II and the commission of the Beijing–Guangzhou railway. The Guangzhou–Hankou railway, the precursor of the Beijing–Guangzhou railway, has connected Guǎngzhōu with Qīngyuǎn, Yīngdé and Sháoguān with Lèchāng (Qīngyuǎnshì Dìfāngzhì Biānzuǎn Bàngōngshì 清遠市地方志編纂辦公室 ‘Qingyuan Chronicles Compilation Committee’ (Qingyuanshi Difangzhi Bianzuan Bangongshi 1995, p. 370; Construction Administration Chu-Shao Section Canton-Hankow Railway 1935); Lèchāngxiàn Dìfāngzhì Biānzuǎn Bàngōngshì 樂昌縣地方志編纂辦公室 ‘Lechang Chronicles Compilation Committee’ (Lechangxian Difangzhi Bianzuan Bangongshi 1994, p. 222); also see Figure 5). The influence from Yuè varieties in the Pearl River Delta as well as the phonological characteristics might thus travel along the rail line to northern Guǎngdōng and leave a trail parallel to the railway, which would also be the case with the contrast between *-iun/iut and *-in/it as well as the rime of “出” as [yt] and [œt] or [øt] (Figure 3 and Figure 4). It is worth noting that that the rime of “出” in northern Guǎngdōng is unlikely to be influenced by Tǔhuà 土話and Hakka in the same region, which pronounce “出” as either [ut] or [-ʔ], over even as an open syllable (Zhuang 2004, p. 99; Zhuang and Bei 2022, pp. 824–25); migrants from the Pearl River Delta and Qīngyuǎn settled into Lèchāng after World War II (Lèchāngxiàn Dìfāngzhì Biānzuǎn Bàngōngshì樂昌縣地方志編纂辦公室 ‘Lechang Chronicles Compilation Committee’ (Lechangxian Difangzhi Bianzuan Bangongshi 1994)), and they probably brought the phonological characteristics of the Yuè varieties in the Pearl River Delta to Lèchāng. Therefore, the distribution of “出” with [yt] in the Pearl River Delta, Qīngyuǎn and Lèchāng is not a random coincidence, but an effect of migration. However, comprehensive studies on modern demographic history, genealogy, as well as the relationship between [yt] and [œt] or [øt] are necessary to thoroughly scrutinize and verify the distribution of “出” as [yt] and [œt] or [øt] in northern Guǎngdōng.

Similar to the case with Lèchāng, the contrast between *-iun/iut and *-in/it, as well as the pronunciation of “出” with final [yt] in Nánníng might have been brought by migrants. Migration to Guǎngxī Province from the Pearl River Delta following the lifting of maritime prohibitions after the First Opium War (1839–1842), as well as that by people escaping the effects of World War II in later times, led to the formation of the large Yōngxún Yuè community in Nánníng. The language of that community is difficult to distinguish from that of Guǎngfǔ Yuè (de Sousa 2022; Kwok 2019, pp. 10–11). This situation provides a plausible explanation for the differing classifications of Nánníng Yuè in the Language Atlas of China and Zhan et al. (2002); Zhan (2004) (Table 1). In light of the phonological features shared between Nánníng and the Pearl River Delta, even with geographical constraints (illustrated in Figure 3 and Figure 4), it is conceivable that the contrast between *-iun/iut and *-in/it, as well as the pronunciation of “出” with [yt] were brought by migrants from the Pearl River Delta to Nánníng.

Considering the demographic history of Nánníng, one may wonder why distinctive distributional patterns are found in Nánníng and the Pearl River Delta in the reflexes of *-iun/iut and *-un/ut (Figure 2). The relationships between the variants [yn]/[yt] and [ɐn]/[ɐt] in Nánníng may help shed some light on this problem. The reflexes of *-iun/iut following alveolar initials such as in *chiun¹ “春” ‘spring’ are pronounced as [yn]/[yt] in old Nánníng Yuè, while they are pronounced as [ɐn]/[ɐt] in new Nánníng Yuè (Lin and Qin 2008, pp. 83–84). This leveling may be influenced by contact with adjacent Yuè varieties in Guǎngxī (Figure 6), which is a type of regional dialect leveling proposed by Kerswill (2003). Considering the reflexes of *-iun/iut and *-un/ut in the Pearl River Delta and northern Guǎngdōng, it is possible that *-iun/iut and *-un/ut were merged as [yn]/[yt] in these varieties and in Nánníng; but these reflexes of *-iun/iut and *-un/ut have now been splitting due to contact influences. This assumption cannot be completely verified in this paper, however, in part because [ɐn]/[ɐt] in the reflexes of *-iun/iut might not be the product of internal regular sound change from [yn]/[yt] in Nánníng, since [yn]/[yt] in the Nánníng reflexes of *-on/ot and *-ion/iot are unaffected and show no variation between [yn]/[yt] and [ɐn]/[ɐt]. To further examine this assumption, intensive fieldwork is needed to obtain more data in the Pearl River Delta as well as for Nánníng. What is certain, however, is that the merger of *-iun/iut and *-un/ut is not a common characteristic in Yuè, as noted earlier in Section 4.1.

4.3. Diffusion Pattern of *-un/ut > [yn]/[yt] and Related Mergers

As shown in Figure 7, the reflexes of *-un/ut following alveolar initials are [yn]/[yt] in the majority of the data sites. This contrasts with the reflexes of *-iun/iut (Figure 4 and Figure 6), again suggesting that different processes led to *-un/ut > [yn]/[yt] and related merger(s).

The reflexes of *-on/ot and *-ion/iot are [yn]/[yt] in some sites such as Guǎngzhōu, Yùlín, Héngzhoū, Xìnyí and Fēngkāi (

Table 7. Pronunciations of *son¹ “酸”, *sun¹ “孫”, *cion¹ “磚” and *tshun¹ “村” in the data sites (examples). #

Sites	*son1 “酸” ‘Sour’	*sun1 “孫” ‘Grandchild’	*cion1 “磚” ‘Brick’ #	*tshun1 “村” ‘Village’
Guǎngzhōu	syn1	syn1	tsyn1	tsʰyn1
Huàzhōu	ɬin1 ɬun1	ɬin1	tʃin1 tʃun1	tʰin1
Yángjiāng	ɬun1	ɬun1	tʃin1	tʃʰun1
Yùlín	ɬyn1	ɬyn1	tɕyn1	tʰyn1
Liánzhōu	ɬun1	ɬun1	tʃun1	tʃʰun1
Héngzhoū	ɬun1	ɬun1	tʃyn1	tʃʰun1
Xìnyí	ɬyn1	ɬyn1	tsyn1	tsʰyn1
Fēngkāi	syn1	sɐn1	tsyn1	tsʰɐn1

# There are no vernacular words which can form a minimal pair from the reflexes of *-ion/iot and *-un/ut. Thus, the relevant contrast is illustrated here with a comparison between *cion¹ “磚” and *tshun¹ “村”, which both have voiceless affricate initials and the same tone in CDC in addition to their shared final.

). Yet that is not an influence from the initials, as can be inferred from the comparison between *son¹ “酸” and *sun¹ “孫”. Plotting the contrast between *-on/ot with *-un/ut (Figure 8) as well as *-ion/iot with *-un/ut (Figure 9), it is clear that these mergers are prevalent in Yuè varieties, although they were reported by only a few researchers, including Liu (2015), Li (2010), Weng (2012) and Xu (2013).7 It is also noteworthy that Yángjiāng, Yángchūn and Héngzhoū maintain the distinction between *-un/ut and *-ion/iot, while the Sìyì subgroup, Huàzhōu, Fēngkāi and Língshān, retain both distinctions between *-on/ot with *-un/ut and *-ion/iot with *-un/ut. These are the varieties located in the southwest of the Pearl River Delta or near the boundary of Yuè, whilst the mergers and *-un/ut > [yn]/[yt] (see also Figure 7) spread from the Pearl River Delta not only to northern Guǎngdōng but also along the Xījiāng 西江 river to Xúnjiāng 潯江 and Yùjiāng 郁江 (Zhàoqìng, Yúnfú, Wúzhoū, Guipíng, Guìgǎng and Nánníng) as well as their branches (Xīnxīng, Luódìng, Xìnyí, Běiliú and Yùlín). Given the higher cultural and economic prestige of the Pearl River Delta in Guǎngdōng and Guǎngxī Province, it is plausible that the mergers and *-un/ut > [yn]/[yt] were diffused westward by a mobile population and their contacts along the river routes.

In the mergers of *-on/ot with *-un/ut as well as *-ion/iot with *-un/ut, literary words show different distribution patterns from vernacular words, revealing a possible diffusion pattern from the center of culture. Figure 10 displays the geographical distribution of the contrast between *-on/ot and *-un/ut, using *son⁵ “算” ‘count’ and *sun³ “損” ’hurt/loss’ as examples of literary words.8 The merger of *-on/ot with *-un/ut is slightly more prevalent than in vernacular words (Figure 8). Furthermore, it is the same case with the merger of *-ion/iot and *-un/ut if literary words (Figure 11) are compared with vernacular words (Figure 9). In these comparisons between literary words and vernacular words, it can be seen that some sites maintain the contrast in vernacular words but lose it in literary words, including Héngzhoū and Fēngkāi. Ongoing sound changes related to [yn]/[yt] in these two sites can be seen if the dataset of this study is compared with two studies from the late 2010s. In Héngzhoū (

Table 8. The reflexes of *-ion/iot and [un]/[ut] > [yn]/[yt] in Héngzhoū.

Word	Héngzhoū (Xie 2007)	Héngzhoū (Mo 2019)
*tshot7 “撮” ‘to assemble’ ‘tuft of’	tʃyt7B	tʃyt7B
*sun3 “損” ‘loss’	ɬyn3	ɬyn3
*tshun5 “寸” ‘inch’	tʃʰyn5	tʃʰyn5
*tson1 “鑽” ‘to bore’	tʃun5	tʃyn1
*tson5 “鑽” ‘drill’	tʃun5	tʃyn5
*son1 “酸” ‘sour’	ɬun1	ɬyn1
*son5 “算” ‘count’	ɬun5	ɬyn5
*son5 “蒜” ‘garlic’	ɬun5	ɬyn5
*tsun1 “尊” ‘respect’	tʃun1	tʃyn1
*dzun2 “存” ‘save’	tʃʰun2	tʃʰyn2
*tshun1 “村” ‘village’	tʃʰun1	tʃʰyn1
*sun1 “孫” ‘grandchild’	ɬun1	ɬyn1
*dzion2 “全” ‘all’	tʃʰyn2	tʃʰyn2
*chion1 “川” ‘stream’	tʃʰyn1	tʃʰyn1
*chion5 “串” ‘string’	tʃʰyn5	tʃʰyn5

), data from Xie (2007) showed that only three reflexes of *-un/ut and *-on/ot were pronounced as [yn]/[yt], including *tshot⁷ “撮” ‘to assemble’ ‘tuft of’, *sun³ “損” ’hurt/loss’ and *tshun⁵ “寸” ‘inch’, of which “撮” and “損” are literary words. For those reflexes which were [un]/[ut] in Xie (2007), Mo (2019) recorded as [yn]/[yt]. In other words, *-un/ut and *-on/ot have changed from [un]/[ut] to [yn]/[yt] in both literary and vernacular words, thus merging with the reflexes of *-ion/iot. Although this change may be led by internal or local factors in Héngzhoū Yuè, it could also be influenced by the contact with adjoining varieties as shown in Figure 7, given the fact that geographical diffusion follows the regularity of sound change (Labov 1994, p. 501; Hui 2022). During a similar time frame in Fēngkāi, data from Zhan and Cheung (1998) reported a literary word *sun⁵ “遜” ‘inferior/modest’ as [sin⁵], while it is [ʃyn⁵] in Hou (2016)9, thus merging with *son⁵ “算” ‘count’ and *son⁵ “蒜” ‘garlic’ as well as sharing the same rime with the reflexes of *-ion/iot (

Table 9. The reflexes of *-on/ot, *-ion/iot and [in] > [yn] in Fēngkāi.

Word	Fēngkāi (Zhan and Cheung 1998)	Fēngkāi (Hou 2016)
*sun5 “遜” ‘inferior/modest’	sin5	ʃyn5
*son5 “算” ‘count’	syn5	ʃyn5
*son5 “蒜” ‘garlic’	syn5	ʃyn5
*chion5 “串” ‘string’	tsʰyn5	tʃʰyn5

). Comparison of Zhan and Cheung (1998) with Hou (2016) supports the finding of a merger of *-un/ut, *-on/ot and *-ion/iot, and the change [in] > [yn] in Fēngkāi. This merger and change might be affected by adjacent Yuè varieties such as Guǎngníng, Luódìng and Zhàoqìng, but given that *tshiun⁵ “俊” ‘handsome’ was affected by [in] > [yn] at the same time and this syllable is [ɐn] in those adjacent Yuè varieties, this merger and change was probably influenced by Guǎngzhōu (

Table 10. The reflexes of *-on/ot, *-ion/iot and [in] > [yn] in Guǎngzhōu, Fēngkāi with its adjacent sites.

Word	Fēngkāi (Zhan and Cheung 1998)	Fēngkāi (Hou 2016)	Guǎngníng	Luódìng	Zhàoqìng	Wúzhoū	Guǎngzhōu
*sun5 “遜” ‘inferior/modest’	sin5	ʃyn5	syn6	syn5	syn6	ɕɐn5	sœn5
*son5 “算” ‘count’	syn5	ʃyn5	syn5	syn5	syn5	ɕyn5	syn5
*son5 “蒜” ‘garlic’	syn5	ʃyn5	syn5	syn5	syn5	ɕyn5	syn5
*tshiun5”俊” ‘handsome’	tsin5	tʃyn5	tsɐn5	tsɐn5	tsɐn5	tɕɐn5	tsœn5
*siun5 “迅” ‘speedy’	sin5	ʃin5	sɐn3	sɐn5	sɐn5	ɕɐn5	sœn5

), which has a higher cultural and economic prestige, as previously mentioned in Section 4.3, in a skewed copy of the [œn] of Guǎngzhōu. Future studies are needed to confirm the source of [in] > [yn] in Fēngkāi, especially a record of *siun⁵ “迅” ‘speedy’, which is recorded as [yn] in Hou (2016). However, what can be inferred from the details of Fēngkāi is that the source of the aforementioned merger and change is contact with Yuè varieties from the east, rather than with Wúzhoū which retains the contrast between *tshion⁵ and *son⁵ as shown in Table 10.

5. Conclusions

The pronunciations of reflexes of *-iun/iut and *-un/ut following alveolar initials are complex in Yuè Chinese, although previous studies did not examine the situation in detail or offer an explanation. This study reveals that the mergers of the reflexes of *-iun/iut and *-un/ut do not prevail in the vast majority of Yuè varieties and are only seen in the Sìyì Yuè subgroup. It was also found that the mergers of *-un/ut > [yn]/[yt] and *-iun/iut > [yn]/[yt] have different diffusion patterns across the linguistic map.

With respect to *-iun/iut, Yuè varieties in the Pearl River Delta, in the north of Guǎngdōng and in Nánníng stand out with the retention of the contrast in the reflexes of *-iun/iut and *-in/-it that is seen in the ancestral forms. Considering the shared development of *-iun/iut > [yn]/[yt] with the historical demography and transportation patterns in these three places, a possible explanation for the coexisting variants and non-variants would be the arrival of immigrants from the Pearl River Delta and the ensuing linguistic contact between speakers of the different varieties.

For *-un/ut, the reflexes of *-un/ut have merged with *-on/ot and *-ion/iot in the majority of Yuè varieties, with the exception of the Sìyì subgroup. In light of the natural geographic environment, the different geographical distribution patterns between literary words and vernacular words suggest that the *-un/ut > [yn]/[yt] merger is ongoing from the Pearl River Delta westward. This is consistent with the fact that the Pearl River Delta has higher cultural and economic prestige.

With these observations, this study provides a methodological contribution to the field of Sinitic dialectology. It highlights the feasibility of applying dialect geography and the historical-comparative linguistic method to scrutinize the phonetic and phonological developments of dialects. However, this study also raises new questions, such as whether or not *-iun/iut and *-un/ut following alveolar initials used to be merged in the Pearl River Delta, and the exact source of [in] > [yn] in Fēngkāi. To uncover the possible answers to these questions, intensive fieldwork with a sociolinguistics base and acoustic analysis is needed to obtain more data for analysis in future studies.