As a response, college and university students in Beijing, Nanjing, Wuhan, Shanghai and Baoding geared up for innovative activities ranging from outdoor lectures, walks, to an unplugged concert.

Some 100 students gathered at the prestigious Peking University in Beijing Saturday night, offering telescopes to passer-bys for them to observe the starry sky.

"Earth Hour should talk about not only climate change, but also the importance of darkness, because light pollution in cities has seriously affect astronomical observation," Liu Boyang, a sophomore majoring in astronomy, told Xinhua.

"I don't expect too many people to heed the call (for turning off lights) tonight. But this should not be only for tonight -- we must do energy saving everyday," he said.

Popular website douban.com asked its users to "log off for one hour."

Even a mimic of the Eiffel Tower in an amusement park in south China's Shenzhen City plunged into darkness before the real one in Paris goes dark eight hours later.

"Enthusiasm of the Chinese individuals and governments (to support the campaign) has been overwhelming, though this is the first year for China to hold Earth Hour activities," Dermot O'Gorman, WWF China Country Representative, told Xinhua.

"This will send an important message to the world that people in China are becoming more aware of climate change issues," he said.