A Geotypological Study On The Corresponding Vowel Categories Of Rhyme Containing A Rounded Front Vowel In Mandarin Dialects Around Beijing

There are many kinds of complex phonetic value types in the dialects around Beijing.Among them,the single vowel[y]in Mandarin has the most distinctive sound value of[uei],such as the corresponding of“驴(donkey)”"ly:luei".In order to find out the geographical distribution of all kinds of phonetic value types,and to explore the causes and process of phonetic changes,we conducted a micro to village level field survey on the dialects around Beijing based on the words of the rhyme containing a rounded front vowel(we call it cuokouhu)in Mandarin.With the results of the original survey in the academic circle,we got a total of 267 dialect data.Based on the status of middle ancient phonology,we classify the Mandarin characters under the jurisdiction of the rhyme containing a rounded front vowels from different sources in Mandarin into different types according to the division and combination of the vowels of the Chinese characters and their hekouhu and qichihu vowels,and project them into the geographic information system to draw 38 dialect maps.By observing the map,we can find the obvious geographical distribution trend,the most important of which is that the evolution from cuokouhu to hekouhu in the area around Beijing is in the shape of "jue 玦"(a ring with a gap at the top).This distribution is related to historical migration.In the early Qing Dynasty,after the Northeast Chinese entered the pass,they replaced the dialects of Beijing,which made Beijing and its surrounding areas form a clear ring distribution.Because of its unique political status and geographical location,Chengde has always been consistent with the language of Beijing,forming a gap at the top of the ring.This shaped distribution itself also shows that the evolution of cuokouhu vowels in Beijing dialect and surrounding dialects should be consistent and continuous geographically before the early Qing Dynasty.In terms of the types of finals,there are some differences between single and compound vowels.The corresponding vowel types of Mandarin single vowel[y]are complex and diverse in dialects,among which the hekouhu type is concentrated in the ring area around Beijing,while the cuokouhu compound vowel of Mandarin is relatively stable in dialects,maintaining the same vowel types as Mandarin in most areas.On the mechanism of phonetic change,through the observation of interpersonal differences and on-the-spot listening experiments,we find that the evolution of "y→uei" of the vowels of the words governed by the single vowel[y]in Mandarin has a continuum:“y→ye→ye→yei→yei→uei".These values can be observed in different places,and in the minds of some speakers,these values are not the same.And it is a phonemic variant that cannot be distinguished subjectively.This change process is also affected by the initial conditions,according to the order of n、1>(?)>(?)、(?),the initial n and 1 complete the sound change first,followed by the zero initial,and the final after (?),(?),(?) changes slowly.