How did Mayan civilization collapse?

London: The irrigation technology that served the Mayans well during periods of drought may have actually made their society more vulnerable to major catastrophes, new research has revealed.

Something really drastic must have happened to the ancient Maya at the end of the Classic Period in the ninth century.

Within a short period of time, this advanced civilisation in Central America went from flourishing to collapsing -- the population dwindling rapidly and monumental stone structures were no longer being constructed.

The socio-hydrological model developed by the Gunter Bloschl-led team at Vienna University of Technology (TU Wien) tell us that droughts and water issues are one possible explanation for their demise and shows us just how vulnerable an engineered society can be.

“It's well-known that the Mayans built water reservoirs in preparation for dry spells," said Linda Kuil, one of professor Gunter Bloschl's PhD students of the Vienna Doctoral Programme on Water Resource Systems.

“With our model, we can now analyse the effects of the Mayans' water engineering on their society. It is also possible to simulate scenarios with and without water reservoirs and compare the consequences of such decisions,” Kuil noted.

The water supply determines how much food is available and, in turn, affects the growth of the population.

As it turns out, water reservoirs can actually provide substantial relief during short periods of drought.

In the simulations without reservoirs, the Mayan population declines after a drought, whereas it continues to grow if reservoirs provide extra water.

However, the reservoirs may also make the population more vulnerable during prolonged dry spells.

The water management behaviour may remain the same, and the water demand per person does not decrease, but the population continues to grow.

“This may then prove fatal if another drought occurs resulting in a decline in population that is more dramatic than without reservoirs,” the authors noted.

"When it comes to scarce resources, the simplest solutions might turn out to be superficial and not always the best ones," Kuil added.

The lessons learnt may also help us to draw important conclusions for our own future.

“We need to be careful with our natural resources. If technical measures simply deal with the shortage of resources on a superficial level and we do not adjust our own behaviour, society is left vulnerable,” the authors pointed out.