By David Montero | Correspondent of The Christian Science Monitor / June 6, 2008 edition
Reporter David Montero discusses the idea of studying climate change on a local level.
Reporter David Montero
Nam Lai, a carpenter in this remote corner of
For years, the 1 million inhabitants of the lake –
Lai’s observations, together with evidence of climate change’s impact on other fisheries around the world, has scientists deeply concerned that Tonle Sap Lake – one of the world’s most fragile ecosystems and one of its most productive fisheries – is also under threat. The lake is essential to
The problem is, nobody knows the impact of climate change for sure – even the teams that have come to find out from as far away as
“There’s a whole area of science that needs to relate climate and physical change to people and social changes – to identify relationships between physical changes and social consequences,” says Eric Baran, research scientist at the Phnom Penh office of the World Fish Center, a research organization headquartered in Malaysia.
The Cambodian government has begun looking at the problem, creating a climate-change office in 2003 and undertaking a climate-change vulnerability assessment in 2001. But neither of those measures has focused specifically on the
Whatever the cause, floating gas-station owner Sinan San has seen the effects firsthand. Her main customers – fishermen – are no longer able to make good catches, and her earnings have dried up since 2004.
“The number of fishermen has decreased because there are less fish, and they move to upland for their livelihood. They say fish are getting smaller and smaller,” she says. Scientists agree, saying overfishing, poor management, and unfair laws have led to a sharp decrease in the number and size of the lake’s fish.
“Small fish are more susceptible to climate fluctuations,” says Mr. Baran. “If the year is good, you have many [small fish]. If the year is bad, you have nothing. This will make the system more and more shaky.”
The declining fish are just one variable in a host of factors that threaten to affect the lake’s hydrology, further exposing it to the risks of climate change.
“Many factors will have impacts on the hydrological regime of the Mekong Basin and on the Tonle Sap Lake’s ecosystem,” Timo Menniken, an adviser to the Mekong River Commission Secretariat in Vientiane, Laos, writes in an e-mail. “These include general rapid economic development, the ongoing development of hydropower schemes along the upper reaches of the Lancang-Mekong, the proposed development of hydropower schemes on tributaries and the mainstream in the lower basin, the indications of groundwater depletion and water pollution caused … by the tourism industry, and plans for oil exploration in the Tonle Sap Basin.”
Another factor is accelerated glacier runoff. “The hydrology can be affected by the melting away of mountain snows in