本研究探討母音共陣峰與鼻音鼻化對華語鼻音結尾之區辨程度。十位台籍華語母語人士與十位緬甸籍以華語爲第二語言學習者參與本聲學研究。發音語料爲三母音語境中([i], [ə], [a])之舌根鼻音與舌尖鼻音([-n] vs. [-η])；聲學分析重點含：母音共陣峰走勢、鼻音鼻化程度、母音時長、與鼻音時長。主要結果指出：母音共陣峰與鼻音鼻化對華語鼻音結尾之區辨扮演重要角色；台籍華語母語人士之母音共陣峰及鼻化程度僅於[an]-[aη]達顯著差異，但於其他兩組([in]-[iη], [ən]-[əη])未達顯著差異，反應出台籍華語鼻音結尾發音合流趨勢。此外，緬甸籍以華語爲第二語言學習者，未因其母語具較複雜鼻音結構而享優勢，亦呈現類似華語鼻音結尾發音合流現象，其混淆程度更劇。

The current study addressed to what extent the murmur and vowel make contribution to the place of articulation distinction in Mandarin Chinese nasal codas. Ten speakers of Mandarin in Taiwan and ten speakers of Burmese who learned Chinese as a second language (CSL) participated in the present research. They articulated the alveolar-velar nasal pairs (i.e. [-n] vs. [-η]) embedded in three vowel contexts ([i], [ə], [a]) with the rising tone. Nasal production of each subject was examined from the perspective of four acoustic cues, including formant transition in vowels, degrees of nasalization, vowel duration, and nasal murmur duration. Results revealed that the spectral difference and nasalization play important roles in the Mandarin syllable-final nasal contrasts. Speakers of Mandarin in Taiwan significantly distinguished the [an]-[aη] pair in formant transition and nasalization, but failed in the other pairs ([in]-[iη], [ən]-[əη]). This finding to some extent reflected the nasal merging in Mandarin production in Taiwan. Though endowed with a more marked L1 nasal system, CSL learners from Burma merged Mandarin nasal codas to a greater degree. Their confusion in producing Mandarin nasals was a major result from the merging nasals of the target language.