An ancient civilisation which helped cause its own demise by inadvertently destroying an ecological keystone offers "important lessons for our management of fragile, arid areas", according to researchers.

Archaeologists examining the remains of the Nasca, who once flourished in the valleys of south coastal Peru, discovered a sequence of human-induced events which led to their "catastrophic" collapse around 500 AD.

The Nasca civilisation disappeared partly because it damaged the fragile ecosystem that held it in place, a study found.

Author Oliver Whaley, of the Royal Botanic Gardens, Kew, said: "The mistakes of prehistory offer us important lessons for our management of fragile, arid areas in the present."

In the study published in the journal Latin American Antiquity, the researchers found that the Nasca cleared areas of forest to make way for their own agriculture over the course of many generations.

In doing so, the huarango tree, which once covered what is now a desert area, was gradually replaced by crops such as cotton and maize.

But the tree was crucial to the desert's fragile ecosystem as it enhanced soil fertility and moisture and helped to hold the Nasca's narrow, vulnerable irrigation channels in place, the researchers said.

The Nasca eventually cut down so many trees that they reached a tipping point at which the arid ecosystem was irreversibly damaged.

An El Ñiño-style flood then occurred, but its impact would have been far less devastating had the forests which protected the delicate desert ecology still been there, they said.

David Beresford-Jones, of the McDonald Institute for Archaeological Research at Cambridge University, said: "These were very particular forests. The huarango is a remarkable nitrogen-fixing tree and it was an important source of food, forage, timber and fuel for the local people.