The Wenchuan quake also helped NGOs to understand the importance of coordination - volunteers didn't respond to the Wenchuan quake until three days after the event, but the NGOs started to move into Ya'an just four hours after the quake.

"This time, our first reaction was not 'We must go there'. Instead, the question was 'What can we do for people?" said Guo. "In this sense, volunteers and NGOs are more rational, and they arrive at a disaster zone with a clear idea of their roles."

NGOs are not specialists in search and rescue operations, said Guo. Their job is to provide immediate help ahead of the official emergency services and to hold the fort until professional help arrives. In the aftermath of the Ya'an quake, the government organized relief operations much more rapidly than in the wake of Wenchuan, leaving little immediate work for the NGOs, who now understand that their efforts will probably be directed toward reconstruction, she added.

Gao Guizi, president of Shangming Charity Development Research Center in Chengdu, has observed the transformation of NGOs with interest. After Ya'an, the local NGOs recommended that Gao should be one of a team to coordinate efforts to aid survivors. He answered so many phone calls that he almost lost his voice.

"The coordinators must decide where supplies are needed and how they can be transported," said Gao, remembering one of the lessons from Wenchuan, when he founded a platform to serve NGOs nationwide.

Gao said the Wenchuan quake can be regarded as a period of "rebirth" for Chinese NGOs, as the focus of charitable efforts and voluntary work shifted to the NGOs and away from the government and established companies.

The past five years have seen a re-evaluation of the role of NGOs, and an increasing number of people have devoted themselves to charitable and voluntary missions, Gao said.

The rise of NGOs in Sichuan, both in terms of numbers and quality of service, can partly be attributed to a change of attitude by the local governments. Since 2011, NGOs have been allowed to register independently in Chengdu, instead of having to find an official "supervisor", a practice that applied to NGOs in other parts of China at the time.

"Chengdu was the only city to provide 500 million yuan to support social organizations. That was one of the city's five major targets in 2011," said Guo.

However, according to Guo, some NGOs still haven't registered, although he didn't give a specific number. In Mianyang, only three out of 10 NGOs have registered. The others have been stymied by a requirement that they must have registered capital of 100,000 yuan, according to one NGO leader in Mianyang who asked not to be named.

Government support is crucial for the development of NGOs, and last year Chengdu's Jinjiang district established a foundation to support a dozen, mainly those serving local communities. In Mianyang, Li's volunteer station is also supported by the local youth league.

"In the coming years, NGOs will grow quickly, but will also face many obstacles," said Gao. "We hope all the fetters can be broken and the volunteers will have more room to perform their roles and help others."

Wu Wencong, Li Yu and Huang Zhiling contributed to this story.