"This year, Earth Hour asks people to commit to an action, big or small, that they will sustain for the future of our planet," organisers said in a statement issued in Singapore.
Among the actions announced Wednesday is a commitment by the Nepalese government to put an end to tree-felling in the Churiya range, a 23,000 square kilometres (9,200 square miles), forest area.
Chinese actor and singer Li Bingbing has pledged to eat a vegetarian diet for 100 days this year to help reduce carbon dioxide emissions caused by the cycle of meat production and consumption, it added.
Pakistani cricket legend Wasim Akram has promised to stop using plastic bags.
Organisers have set up a website, www.earthhour.org/beyondthehour, on which individuals, organisations and governments worldwide can post their pledges.
Earth Hour will be marked this year on March 26. Last year, hundreds of millions of people worldwide took part in the event by switching off their lights for an hour.
But environmental campaigners said the turn-off was "only the beginning".
Jim Leape, director general of environmental group WWF International, which helped initiate the movement, said small individual actions can go a long way to saving planet Earth.
"The challenges that face our planet are immense, but never underestimate the possibility for change when we face these challenges with true common purpose," he said.
"It is now time to go beyond the hour and show what can be done -- by the people for the planet."
Andy Ridley, Earth Hour co-founder and executive director, said "social media will play a crucial role for Earth Hour 2011, allowing us to connect with millions of people who are committed to taking lasting action for the planet."
The website is available in 11 languages and is integrated with social media networks such as Facebook, Twitter, Mixi and Myspace.
"Everyone has the power to make change -- a CEO can change an organisation, a seven-year-old can change a classroom and a president can change a country," Ridley said.(*)
Editor: Aditia Maruli Radja
Copyright © ANTARA 2011