Scientists’ model calculations in TU Wien may have found a (new) explanation
The reasons why the advanced Mayan civilization rapidly went into decline at the end of the 9th century may always remain under doubt: war, epidemics, deforestation, adaptation to climate change could all have played their part. Poor water management and an increasing population should also be added to the list, according to a new research. Scientists from TU Wien, using a mathematical model, came to the conclusion that the water reservoirs built by the Mayans for drought periods may have actually made their society more vulnerable to major catastrophes. That’s because in case they run dry, the drought impact could be even more severe for the population. The study was published in Water Resources Research.
Socio-hydrology is a field that aims, via mathematical interrelationships (for example between food availability and birth rate) to understand how water supply and management systems affect populations. ‘Water influences society, and society influences water’, says Linda Kuil, PhD student at TU Wien and member of the research team. ‘The water supply determines how much food is available, so in turn affects the growth of the population. Conversely, population increases may interfere with the natural water cycle through the construction of reservoirs, for example. It's well-known that the Mayans built water reservoirs in preparation for dry spells’, she continues. ‘With our model, we can now analyze 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.’
The research team explored the hypothesis that modest drought periods played a major role in the society's collapse. The simulations showed that a modest reduction in rainfall may lead to an 80% population collapse. Population density and crop sensitivity to droughts, however, may play an equally important role. It seems that the water reservoirs provided a relief during short periods of droughts and ensured the population’s growth. However, during prolonged dry spells, the population is vulnerable in case the water management behavior remains the same, and the water demand per person does not decrease. If another drought occurs, it could have far more dramatic consequences compared to a society without reservoirs. ‘When it comes to scarce resources, the simplest solutions might turn out to be superficial and not always the best ones’, Linda Kuil believes. ‘You have to change people's behavior, reassess society's dependency on this resource and reduce consumption—otherwise society may in fact be more vulnerable to catastrophes rather than safer, despite clever technical solutions.’
The findings are very important for our days as well, and the sustainable use of resources should always be a priority in order to prevent being exposed to similar phenomenon.
Source: Phys. Org