In this story, we return to the beauty of Earth, where while we can get up close and personal with our research areas, sometimes we have to use more remote methods to make our observations. In our next story, a team of scientists used lidar observations as well as on-site excavations to examine the Birds of Paradise wetlands in Belize for evidence of just how the Maya survived changing conditions like drought. It turns out that they managed the soil and the water of the region with an extensive system of canals!

The team predominantly used soil analysis to determine just how the agricultural system in the region functioned. They analyzed the sediment in the canals, measuring the ratio of pollen and dating the carbon isotopes found in materials like charcoal and mollusk shells. They found that the Maya began this canal system about 2,100 years ago and used it to distribute water and manage a variety of crops, including squash, maize, avocado, and a variety of other fruits. These crops were grown in blocks surrounded by canals and causeways, and because the water could be distributed throughout the wetland area, the people living there managed to survive droughts.

In fact, the canal system was so extensive by the fifth century CE that the blocks can still be seen today in those lidar scans. Not only that, but the local Mayan population actually outlasted what is known as the Classical Period. The nearby city of Gran Cacao, which likely managed the region in general, collapsed around 900 CE due to drought and political unrest; however, this most recent analysis shows that Mayan society in the Birds of Paradise wetlands continued up until the mid-fourteenth century. At that point, the pollen in the soil begins to revert to the natural forest pollen rather than the crop pollen, indicating that no one was managing the local agriculture any longer.

The canals have long since fallen into disrepair, but their effects on the region remain. There is greater ecological diversity in the Birds of Paradise wetlands than in the surrounding areas that were not managed as heavily by the Maya. They attract larger animals like tapir and deer, and the local descendants continue to harvest the same mollusks and fish that have been feeding people for millennia.

This work was published in the journal Anthropocene, and as lead author Sheryl Luzzadder-Beach notes: These are still lasting hydrological impacts.

Humanity’s actions can outlast the people who made them…

More Information

Eos article

“Tropical wetland persistence through the Anthropocene: Multiproxy reconstruction of environmental change in a Maya agroecosystem,” Samantha Krause et al., 2021 March 3, Anthropocene