Shanghai's environmental protection workers are fighting to rid
local waterways of water hyacinth, an invasive aquatic species that
has multiplied in the wake of typhoons Wipha and Krosa.
Rivers and lakes in suburban Shanghai, including the Songjiang,
Fengxian and Jinshan districts, have recently been clogged with
thousands of tons of the floating plants.
File photo: The Suzhou
Creek in Shanghai
Water hyacinth frequently invades Shanghai's major waterways,
such as Huangpu River and Suzhou Creek, blocking traffic and
preventing swimming and fishing. Water hyacinth infestations also
stop sunlight and oxygen from getting into the water, while the
decaying plants also reduces the water's oxygen content.
The plant from South America, an invasive species endangering
biodiversity, has been widely recognized as a harmful weed reducing
fish stocks and shading submerged plants.
The city's environmental protection workers are currently
engaged in a race against time, fishing out 2,000 tons of the
rapidly growing plant from the city's waterways every day.
Outbreaks of water hyacinth do not normally occur in Shanghai
until the end of October, but, this year, it started to appear at
the end of July.
Since Shanghai has enjoyed an exceptionally long summer this
year, the warm climate undoubtedly provides this South American
plant with an ideal environment to grow in.
In addition, the two recent super typhoons Krosa and Wipha are
another factors behind its boom. "When the typhoons arrived, water
hyacinths scattered in the branches of Huangpu River were collected
by the strong wind, and covered the river from shore to shore,"
said Teng Yinbao, vice-director of Shanghai Water Environment
Development Company.
"If you leave them in rivers over a while, they make a absolute
mess. We must get them out as soon as possible, or traffic on
several rivers will be halted," he added.
(China Daily October 14, 2007)
