Central America: Maya contributed by clearing to their own demise

Even 1,000 years after the downfall of the Maya, it is possible to measure where the people have cut down rainforests. The secret lies in the carbon saturation of the soil.

Central America: Maya contributed by clearing to their own demise

Where today Mexican peninsula of Yucatán borders Guatemala and Belize, a few thousand years ago Empire of Maya extended. In an area as large as Germany, highly developed people prevailed until company collapsed and disappeared about 1,000 years ago.

An international team of scientists has now investigated soils in former Mayan settlement area and found astonishing: it is still possible to prove where Maya have cleared rainforest. The results of study were published in journal Nature Geoscience. The decisive proof was provided by carbon stored in soils.

Organic material contains carbon. The soil absorbs element when, for example, leaves, roots or branches die off, and stores it. This storage of carbon is also important for agriculture, because more carbon in soil leads to a more fertile soil. But where no forest grows, re is less organic mass.

The researchers have now succeeded in demonstrating soil samples from bottom of several lakes in former Mayan empire that soils still store less carbon re than in pre-deforestation period. Although cleared forest had grown, much less carbon was stored in region.

Deforestation contributed to demise

"The ecosystem seems to have changed fundamentally and never recovered," said geochemist Peter Douglas of McGill University in Montreal, who led investigation. According to researchers, Mayans who fell on Yucatan Peninsula thus contributed to ir own demise. Before and 4,000 years, Maya had created first fields. For farmland, forest had to be soft.

The study provides new insights into development of carbon storage for centuries and millennia. According to researchers, figures show a dramatic change – because presence of carbon in soil also has an influence on climate. Just as soils can determine carbon, y also put it into atmosphere in form of carbon dioxide. The next goal for Geochemist Douglas is to "analyze tropical forests in or regions as well". In this way, it is possible to find out wher grubbing-up and agriculture in past have influenced carbon stores worldwide.

Date Of Update: 21 August 2018, 12:00