China had 19.87 million Internet bloggers at the beginning of November -- a 24 percent increase over the past 12 months.

While more than 15 percent update their blogs at least once a week, only 4.6 percent do it daily, Baidu found. Blogs devoted to medicine and education are particularly popular, the Xinhua news agency said Wednesday, quoting a study by search engine Baidu.

The report came some six weeks after state press reported that China intends to require its millions of Internet bloggers to emerge from the shadows and register under their real names in a move that is raising privacy concerns.

Under the system, bloggers would be allowed to continue using their online pseudonyms, but must register with authorities under their real names, Xinhua said.

Xinhua quoted the head of the Internet Society of China, Huang Chengqing, as saying that some bloggers used their anonymity to disseminate "irresponsible and untrue" information, and called them a "bad influence".

Huang acknowledged the concerns over free expression, but said there needed to be a balance between freedom and responsible Web use.

Huang gave no firm timetable for implementing the system, saying authorities would listen to feedback from online users before deciding its final shape.