Shanghaiist: Drought in southwestern China

nanheyangrouchuan

Tue, 22 Aug 2006 16:53:38 +0800

less trees will result in more silty runoff ie land erosion. It's pretty tough to pump mud and mud doesn't flow very easily in gravity fed irrigation canals. Mud also kills machinery if you try to use it for a coolant. Trees can't consume surface water very fast, only their leaves and roots can absorb water and osmosis is very slow. Forest canopies only mean that water won't hit the ground evenly, but it still will reach the ground and most of it will still flow downhill into a stream or river. Discovery channel shows on rainforests are proof enough. Those forest canopies are far denser than anything in Yunnan and it is still easy to get drenched while standing around under the trees. Local officials are pretty stupid, drag their knuckles and smoke too many cigarettes.

epay

Tue, 22 Aug 2006 14:42:01 +0800

"Trees don't cause drought." Obviously -- but it is possible for those 'big bosses' to make a fairly coherent argument that fewer trees will translate into more runoff. Forests don't produce drought, but forests, just like factories and irrigation, are capable of diverting water: canopy cover, less compacted soil (root breakup), and litterfall on forest floors divert rainfall from flowing downstream. I'm not contending that deforestation is good drought control policy -- in fact, it is a horrible idea -- I'm merely suggesting that Yunnan local officials are aching for any excuse to reverse the logging ban... and I sure hope they don't pick this one.

nanheyangrouchuan

Tue, 22 Aug 2006 14:08:44 +0800

"big boss abuse" means local big bosses taking water they shouldn't for whatever wasteful, fraudulant products they have going on at the time. "Big boss" deforestation could lead to muddying of waters which make them less usable for irrigation and consumption.

nanheyangrouchuan

Tue, 22 Aug 2006 13:35:22 +0800

Deforestation/Forestation affects soil retention and therefore silt levels in a body of water. Trees don't cause drought. Draining aquifers, diverting water volume and less rainfall creates drought. You don't even need high temperatures, as warm air holds more moisture than cold air, but usually high temps accompany a drought. A policy of deforestation would only create bigger mudslides, possibly taking rice paddies along, and add more silt to big rivers like the Yangtze, which really doesn't need more of anything.

epay

Tue, 22 Aug 2006 12:00:22 +0800

Between climate change, diversion projects, and industrial abuse of water resources, I'm not shocked there is a severe "drought." Chances are, though, this is contributing: In 1998, there were HUGE floods which were traced in part to deforestation. Logging was (and still is) banned in much of Yunnan and Sichuan province, and there is a huge push to reforest these areas. Wouldn't it be ironic if the government decided to reverse the policy and promote heavy logging to increase water flow downstream? also, big boss abuse sounds kinda kinky

peijin

Tue, 22 Aug 2006 10:01:26 +0800

what do you mean by "big boss abuse?"

nanheyangrouchuan

Tue, 22 Aug 2006 02:43:18 +0800

Since 3 gorges dam is downstream, how could it cause a drought? The north-south project and local big boss abuse shares blame with global warming.