Invasive alien species cause billions of yuan of damage in China

Ragweed, a plant native to North America, has been quickly spreading in China from south to north in the past 70 years, sterilizing arable land and reducing crop output. Its pollen causes people to suffer from allergic rhinitis and bronchitis.

Such stories of invasive alien species are not strange to Chinese nowadays. Amazonian snails, bull frogs, termites, and South American Climber ragweed are among them. With no natural enemies in the new environment, they are destroying China's biodiversity in the process of swallowing local species.

"China's invasive alien species had reached 283 kinds by 2003, including terrestrial plants and invertebrates, aquatic invertebrates and microorganisms," said Xu Haigen, a research fellow of the Nanjing Institute of Environmental Sciences of the State Environmental Protection Administration (SEPA).

Statistics from the SEPA show that as early as in 2000, the Chinese economy suffered 119.876 billion yuan of losses from invasive alien species, accounting for 1.36 percent of China's GDP that year, with 100.017 billion going to indirect economic losses in the country's ecological system, species and genetic sources.

"Invasive alien species have become the second biggest biodiversity problem after habitat damage for China," said Xu.

People's lack of awareness of protecting biodiversity should, he said, be blamed for the wide spread of invasive alien species in the country.

According to his investigation, 39.6 percent of the 283 species are brought in purposely, apart from 3.1 percent of natural transfer and 49.3 percent of unconscious import.

"Some people have a wrong impression that foreign species are better than local ones," he said. "Moreover, China lacks effective supervision and assessment of a species' biosafety. People just import species without proper management."

The Amazonian snail, that originates from the Amazon Valley, is a case in point, said Xu, as it has eaten up large patches of paddies in south China after being thrown away by snail raisers for failing to attract food buyers.

"It's important to make a biosafety law very soon to regulate every link of alien species import. After all, protecting biodiversity is protecting humans themselves," he said.

Source: Xinhua