Environmental protection will be the theme of the opening ceremony of the IAAF World Championships, according to the director of the ceremony.

The IAAF World Championships is the first international sports event to be held in Beijing since the 2008 Olympic Games. The opening ceremony will take place on Aug 22 at the National Stadium, which was the main venue for the 2008 Beijing Summer Olympics. The closing ceremony will be held on Aug 30.

The biggest visual impact of the ceremony is a "tree" that has been "planted" in the stadium, connecting the ground and the rooftop of the structure, said Jia Ding, director of the opening ceremony.

Actors rehearse for the opening ceremony of the event. Wei Xiaohao / China Daily

"It looks as if the tree's roots are reaching into the ground or that the tree is growing right out of the ground into the sky," Jia said. "Heaven and earth are connected by the tree."

Jia said harmony with the environment is the theme of the opening ceremony, so simplicity is the signature of the event.

"The ceremony lasts for 50 minutes. Throughout the ceremony, 1,471 people will be performing, including the orchestra and the chorus."

Eight hundred of the performers are from a martial arts academy in Henan province.

"The opening ceremony is going to take place during the daytime, which has made it all the more difficult because we don't have the light to create a focus for the viewers' attention," Jia said.

Chinese cultural symbols, such as square residential courtyards and the Great Wall, will appear during the ceremony, Jia said.

The music and show will actively engage the viewers, said He Qi, the musical director of the ceremony, with audience members given torches with which to take part.

"We have connected a lot of Chinese cultural elements into the track and field sports. Growth and dreams will be two important messages of the music," He said.

Li Yundi, one of the best-known pianists in China, will play during the opening ceremony.

Continuing the environmental theme, the medals are shaped as leaves.

The organizers also selected seven Chinese track and field athletes to work as promotional ambassadors for the event. They include 2004 Olympic hurdles champion Liu Xiang, 2012 Olympic race walking gold medalist Chen Ding and promising long jumper Li Jinzhe, who finished second at the 2013 World Indoor Championships.

As of Aug 15, 1,936 athletes from 207 countries and regions had signed up for the event, according to the organizing committee.

China has 69 athletes competing and has, thus far, sold 570,000 tickets.

"We have been preparing for the event for five years," Du Zhaocai, vice-president of the organizing committee of the World Championships, told China Sports.

"This is the first time that the World Championships has been held in China. Now we are fully prepared for this prestigious international event.

"The World Championships this year has great significance for Beijing because it offers a great occasion to promote sports among the general public. One of the innovations is that we will call up 10,000 amateur marathon runners to run together with professionals. But the amateurs run for only 10 kilometers. Marathon has become a very popular sport in the world. Our initiative will engage more common people in this sport and further promote it," Du said.

duxiaoying1@chinadaily.com.cn