The economic, social and ecological losses brought by several non-indigenous critters cost about 56 billion yuan (US$6.7 billion) each year in China, experts said.

In the past several years, foreign bugs have been introduced in large numbers and have spread across the Chinese mainland.

The pinewood nematode, also called "xianchong" in Chinese, was initially introduced to China in 1982 and thrives in the Yangtze River basin and southeastern coastal cities.

The pinewood damaged by this insect accounts for one quarter of the total forestry area that faces destruction, experts said.

"Almost all kinds of ecosystems are facing deadly threats from exotic deleterious invaders. A total of 20 million mu (1.3 million hectares) of forests are in danger each year," said Zhu Lieke, deputy director of the SFA.

This is why the administration has taken more effective and advanced measures to assign 510 national monitoring stations tasks ranging from quarantine to monitoring.

Each station was given 80,000 yuan (US$9,600) in initial assets and is given an additional 20,000 yuan (US$2,400) every year by the Ministry of Finance to fund their operations.

"The transfer of work emphasis from quarantine to monitoring is a big breakthrough which makes the working mechanism not only more effective, but also less expensive," said Wu Jian, director of the Prevention Department for Plant Diseases and Insect Pests.

The biggest advantage of a monitoring station is that it can detect and find any potential disease and pest before an ecological tragedy breaks out and thus dramatically reduce costs both financially and ecologically.

With China's entry into the World Trade Organization, more and more international exchanges on imports and exports will take place, making it much easier for non-indigenous species to travel across borders.

"Tragedies aroused by such species deserve attention by the State. They not only lead to economic losses, but also endanger ecological safety, which has great impact on the environment, national land resources, national defence and military construction," Wu said.

"Tightening the monitoring procedure is a wise and economical way to curb imminent ecological disaster."

(China Daily November 25, 2002)