As China Booms, Invasive Species Flood in

Such plants already block passage through canals during flood season in the south of the country. They may find their way north more quickly once the massive South-to-North Water Diversion Project is complete. The project will carry water to the north of the country through a system of three canals.

"It's a direct conduit along which these aquatic species can move across the country," Mack said.

China's attempts to beautify Beijing in advance of the 2008 Olympic Games may further exacerbate the invasive species problem. From 2002 to 2004, more than 31 million non-native seedlings and 132,000 pounds of seeds were planted in the city.

"It will definitely be a hidden cost of the Olympics," said William Gregg, former program coordinator for the U.S. Geological Survey Invasive Species Program in Reston, Va.

These plantings may not themselves become invasive, Mack said, but they may bring hitchhikers, and invasions may take time to develop. The good news is that authorities in China are keen to improve quarantine and inspection procedures for the Olympics and beyond, he added.

"Whatever they do, it needs to go well beyond the time that the games are held," he said, pointing to an unusual moment of foresight in U.S. history.

When the city of Philadelphia held a centennial exhibition in 1876, a botanist checked the grounds for four years after the event to look for any new species.

"I think, frankly, we'd have fewer of our own problems with invasive species if that kind of foresight had continued," Mack said.

Related Links:

Larry O'Hanlon's blog: Earth Impacts

Richard Mack's Web site

USGS Invasive Species Program

Overview of Invasive Species in China (2000)

Planet Green

How Stuff Works: Invasive Species