"We saw signs that embankments had been breached and of ad hoc repairs to bridges and dams, suggesting that the system became unmanageable over time." said Damian Evans, the author of a paper published in the Proceedings of the National Academy of Sciences.
"Angkor was extensive enough, and the agricultural exploitation intensive enough, to have created a number of very serious
environmental problems," he said.
Deforestation, over population, topsoil erosion and degradation with subsequent sedimentation or flooding could have been disastrous for
the medieval population, he said.
The settlement surrounding Angkor, the one-time capital of the illustrious Khmer empire which flourished between the ninth and 14th
centuries, covered a 3,000 square kilometre area.