THE GOVERNMENTS of Wuxi in Jiangsu province, and Changsha, capital of Hunan province, announced that their GDP last year exceeded 1 trillion yuan ($154 billion). Beijing News commented on Tuesday:

A GDP of 1 trillion yuan is the threshold for joining the big city club in China. So now there are 14 cities in the club, with the GDP of Shanghai, Beijing and Shenzhen more than 2 trillion yuan.

These 14 cities play important roles in regional and national development. Statistics show that together they account for nearly 30 percent of the national economy.

The competition among cities is increasingly fierce, which means that not only will the club membership continue to expand, but the existing members will compete with one another.

Some recent members of the club, such as Hangzhou, Chengdu, Suzhou, Nanjing, Wuhan and Wuxi, are strong in emerging industries, and they have worked hard to improve the quality of life for residents.

And the prosperity of these big cities generates spillover effects, benefiting the surrounding counties and the satellite towns, producing more balanced urbanization.

But decision-makers in cities must be vigilant to prevent and control urban diseases, such as traffic congestion and air pollution, which accompany fast urban expansion. Also these cities should take measures to avoid polarizing the development in their respective provinces. Chengdu and Wuhan already account for more than half of the economy in their respective provinces of Sichuan and Hubei, attracting resources from all over the province. If this trend is unchecked, the rise of these cities is nothing but false prosperity based on the drying up of the rest of the province.