Eloquent speakers of Shanghai dialect may have the privilege of having their voices recorded, as Chinese linguists move to the eastern economic hub to build a vocal database of local dialects and ethnic languages in China.

Local residents who master the distinctive dialect of Shanghai will be asked to impart local legends, recall old customs, and even sing operas using the dialect in front of language experts and recording equipment.

Starting on Thursday, the two-year project in Shanghai will be the third of its kind to complete a nationwide vocal database, an ambitious move of China to better preserve its linguistic diversity.

Initiated in 2008, the collection and recording have been conducted in Jiangsu and Yunnan provinces. Yunnan is home to the people of Han, as well as those of 25 other ethnic groups, the most number in the country.

In Shanghai, linguists will select volunteers from 12 sites of observation set in all the urban districts and suburban counties of Shanghai, said Li Yuming, a senior official with the Ministry of Education.

Their pronunciations of the Shanghai dialect and their accents in putonghua will be recorded, while linguists will also study nuances in samples taken from different parts of the city.

Shen Xiaoming, vice mayor of Shanghai, said the database would help record the rapid changes of the Shanghai dialect due to increased interactions of the local people with the city's immigrants.

"The Shanghai dialect sounds differently when it was uttered by younger Shanghai residents born in the 1980s and 1990s, while traditional records such as dictionaries have difficulties in recording such distinctions," said Shen.

China has more than 80 languages spoken by the people of its 56 nationalities and an unaccounted number of local dialects.

A nationwide vocal database will facilitate the protection of local dialects and related folkways by aiding in policy-making, said Li Weihong, the vice minister of the Ministry of Education, who insisted that it would help provide better local language services, such as translation.

The nationwide vocal database is expected to be finished in ten years.