Deforestation Floods Wiped Out the Ancient Nazca of Peru

News in Discover Magazine from ancient Peru:
The new study, published in the journal Latin American Antiquity, found that the pollen in the older layers of soil came almost entirely from huarango trees. But by A.D. 400, pollen from corn and cotton plants had replaced the tree pollen, suggesting that the Nazca people had chopped down the forests to make room for agricultural fields. About AD 500, a major El Niño built up in the Pacific, deluging the nearby Andes with rain. Walls of water and mud washed down the valley and over the denuded landscape, sweeping away food crops, buildings and artifacts. Beresford-Jones compared it with the 1997-98 El Niño, which left the city of Ica 6 feet underwater [Los Angeles Times]. The floods of A.D. 500 were many times worse, the researchers say.
Does this sound at all like the Georgia floods of 2009?