The Beijing International Horticultural Exhibition opened just two days before the May holiday, giving the public a close-up view of state-of-the-art gardens created by horticulturists from around the world.

China hosted a similar exhibition in Kunming, Yunnan province, in 1999. In the two decades since, the social and economic situations in China have undergone tremendous changes. A growing awareness of environmental protection is one of them.

Two decades ago, the Chinese people embraced the Kunming horticultural show as a novelty and curiosity because the country at that time did not have many opportunities to host large international gatherings.

Economic development at the time was the top priority of the country, which explains why the news media were so interested in reporting that 15 billion yuan ($2.23 billion) in economic and trade deals were inked during the exhibition.

In the years since, the country has continued to maintain a breakneck pace of economic development, which has brought booming economic prosperity.

Unfortunately, it has also brought a deteriorating environment. Seeing heavy smog, for example, many people feel that a worsening environment will destroy the happiness brought by economic growth.

Since 2012, the new leadership under President Xi Jinping has put forward a series of ecological ideas. On Sunday, Xi said at the opening ceremony of the exhibition that "green mountains and clear waters are indeed mountains of gold and silver, and environmental improvement means great productivity".

This idea, dubbed the theory of two mountains, enjoys immense popular support in China.

Xi, who is also general secretary of the Central Committee of the Communist Party of China, urged officials at all levels never to sacrifice the environment for economic growth.

The development model of "killing the hens to get the eggs" and "draining the lake to get the fish" has reached a dead end, Xi said.

"We should protect the ecological environment as we protect our own eyes, and treat the environment as we treat our own lives," he said.

The president, who has advocated building a community with a shared future for mankind, also brings an international perspective to environmental protection.

"In the face of environmental challenges, all countries are in a community with interlinked destinies, and no country is immune," Xi said at the opening ceremony.

The exhibition attracted more than 110 countries and international organizations, as well as more than 120 unofficial exhibitors.

About 10 heads of state and prime ministers attended the opening ceremony.

We hope the exhibition, which lasts 162 days, will become a platform for people to experience natural beauty and to better understand, and then materialize, Xi's wonderful ecological ideas.

When the sustainable development goals are firmly established in people's minds, the significance of hosting the exhibition will have been achieved.

The writer is deputy editor-in-chief of China Daily.