Deforestation caused by the activities of the Mayan civilization around 4,000 years ago decimated the carbon reserves of the soil in this tropical zone, according to a study published today by the journal "Nature".
The clearing of forests in the Yucatan peninsula and areas of Guatemala by the Mayans is one of the factors believed to have influenced the disappearance of this pre-Columbian culture, point out the authors of the research, led by Yale University ( USA) and McGill University (Canada).
However, since they mysteriously left their cities more than a thousand years ago and the vegetation returned to the area, deforestation continued to affect the region much later, shortening the time that the soil is able to retain its carbon stocks.
The conclusions of this study published by Nature highlight the importance of the type of treatment that humans give to tropical soils, since it can determine future levels of greenhouse gases in the planet's atmosphere.
“When you go to those areas today, almost everything looks like an ancient, dense tropical forest. But if we examine soil carbon stocks it appears that the ecosystem was radically transformed and never returned to its original state“, Explains in a statement the main author of this work, Peter Douglas, from McGill University.
The soil, he points out, contains large amounts of organic carbon that it can retain for thousands of years, preventing it from escaping into the atmosphere, and although it is believed that the alteration of vegetation affects these reserves, its effects vary depending on the type of soil and the nature of the interference.
In this sense, Douglas and his colleagues analyzed the changes that occurred in the time that carbon stocks remained"Kidnapped" in the soil of the Maya lowlands during the last 3.5 billion years, through the dating of the earwax produced by the leaves of plants or present in lake sediments.
The experts found that the amount of time that these waxes remained in the soils decreased during periods of extensive land use.
On the contrary, it began to increase as the population density of the Mayan communities decreased and, in some regions, they changed their exploitation model to manage the soils more effectively.
However, they stress, the carbon residence times never returned to the levels recorded before deforestation, suggesting that soils lose their storage properties even when vegetation returns to the surface.
They also found that deforestation that occurred over the past 150 years has further reduced the ability of the soils analyzed to retain carbon stocks.