New reports from the Greater Angkor Project have hit the newspapers today. The upshot is that more support for Angkorean decline on the basis of compromised ecology and especially water usage systems can be found in the new maps of Angkor.
Angkor was not only huge, it was the largest pre-industrial city. Its power was symptomatically recognized in its constructions, cultural influence, and military might, but was based on intensive rice agriculture. Although some have argued that trade and elite gift giving might have formed the basis of Angkorean power, it is still very clear that the largest-traded commodity was rice, especially in trade with those outside of the Angkorean political complex.
The expansion of dense habitation around the temple capitals, along with the spread of intensive cultivation, seems to have necessarily led to increased clearing of forest lands, which then eroded into the waterways and effectively began to grind rice production in the core area to a halt. No water, no rice.
According to Mr Evans, the map also provides hard evidence backing the controversial hydraulic hypothesis.
This states that Angkor was linked by a vast network of irrigation channels, storage ponds and reservoirs. As the city grew, land was cleared, causing soil to clog the channels. Eventually, it became too expensive and complicated to keep the system free-flowing and it collapsed, taking Angkor with it.
The city, in essence, engineered its own demise by disrupting the environment.
“We can certainly see there were problems in the hydraulic networks,” said Mr Evans.
“There’s evidence of water courses punching through dykes and inadequate attention (to maintenance).”
Said Professor Fletcher: “It’s a cautionary tale for the modern world.”
And while the long-time regional identification of forests as guarantors of water supply may be an ecological falsehood, it clearly has some sort of historical experience behind it: killing of the forests may not destroy water, but it certainly makes it less amenable to the sort of centralized control necessary for imperial life.