From Cambodia to California industrial-scale sand mining is causing wildlife to die local trade to wither and bridges to collapse. And booming urbanisation means the demand for this increasingly valuable resource is unlikely to let up
Times are good for Fey Wei Dong. A genial middle-aged businessman based near Shanghai China Fey says he is raking in the equivalent of ￡180000 a year from trading in the humblest of commodities: sand.
Fey often works in a fishing village on Poyang Lake China`s biggest freshwater lake and a haven for millions of migratory birds and several endangered species. The village is little more than a tiny collection of ramshackle houses and battered wooden docks. It is dwarfed by a flotilla anchored just offshore of colossal dredges and barges hulking metal flatboats with cranes jutting from their decks. Fey comes here regularly to buy boatloads of raw sand dredged from Poyang`s bottom. He ships it 300 miles down the Yangtze River and resells it to builders in booming Shanghai who need it to make concrete.
The demand is voracious. The global urbanisation boom is devouring colossal amounts of sand – the key ingredient of concrete and asphalt. Shanghai China`s financial centre has exploded in the last 20 years. The city has added 7 million new residents since 2000 raising its population to more than 23 million. In the last decade Shanghai has built more high-rises than there are in all of New York City as well as countless miles of roads and other infrastructure. [My sand helped build Shanghai Pudong airport" Fey brags.
Hundreds of dredgers may be on the lake on any given day some the size of tipped-over apartment buildings. The biggest can haul in as much as 10000 tonnes of sand an hour. A recent study estimates that 236m cubic metres of sand are taken out of the lake annually. That makes Poyang the biggest sand mine on the planet far bigger than the three largest sand mines in the US combined. [I couldn`t believe it when we did the calculations" says David Shankman a University of Alabama geographer and one of the study`s authors.
All that dredging researchers believe is a key reason why the lake`s water level has dropped dramatically in recent years. So much sand has been scooped out says Shankman – 30 times more than the amount that flows in from tributary rivers – that the lake`s outflow channel has been drastically deepened and widened nearly doubling the amount of water that flows into the Yangtze. The lower water levels are translating into declines in water quality and supply to surrounding wetlands. It could be ruinous for the area`s inhabitants both animal and human.
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