Ancient Mayan reservoirs, which used aquatic plants to filter and purify water, “serve as prototypes for natural, sustainable water systems to address future water demands,” according to a new paper. There is a possibility.”
Lisa Lucero, an anthropology professor at the University of Illinois at Urbana-Champaign, writes from one perspective that the Maya built and maintained reservoirs that they used for more than 1,000 years. Proceedings of the National Academy of Sciences. These reservoirs provided drinking water for thousands to tens of thousands of people in the city during the five-month dry season and prolonged drought each year.
“Many of the major cities in the southern Maya lowlands arose in areas that had excellent agricultural soils but no surface water,” Lucero said. “They compensated by building reservoir systems that started small and increased in size and complexity.”
Innovative water filtration technology
Over time, the Maya built canals, dams, locks, and dog runs to channel, store, and transport water. They used silica sand to filter water, sometimes importing it from far away to large cities like Tikal in what is now northern Guatemala. Sediment cores from one of Tikal’s reservoirs also revealed that zeolite sand was used in its construction. Previous studies have shown that this volcanic sand can filter impurities and disease-causing microorganisms from water. The zeolite is also believed to have been imported from some 30 kilometers away.
“Tikal’s reservoir can store more than 900,000 cubic meters of water,” Lucero wrote. Estimates suggest that up to 80,000 people lived in and around the city during the Late Classic period, approximately 600 to 800 AD. The reservoir kept people and crops hydrated during the dry season, Lucero said.
Mayan royalty derived much of their status from their ability to provide water to their people.
“Clean water and political power were closely linked, as shown by the fact that the largest reservoirs were built near palaces and temples,” Lucero wrote. Kings also performed rituals to gain favor with their ancestors and the rain god Chak.
Aquatic plants of Maya reservoir
A key challenge was to prevent water in reservoirs from becoming stagnant and undrinkable, and for this the Maya likely relied on aquatic plants, many of which still live in the wetlands of Central America. Lucero said. These include cattails, sedges, and reeds. Some of these plants have been identified in sediment cores from Mayan reservoirs.
These plants filtered the water, reducing turbidity and absorbing nitrogen and phosphorus, Lucero said.
“The Maya would have had to dredge every few years… (and) harvest and replenish aquatic plants,” she writes. The nutrient-rich soil and plants extracted from the reservoir could be used to fertilize urban fields and gardens.
Symbolism and practicality of water lilies
The most iconic aquatic plant associated with the ancient Maya is the water lily. water lily ampuraThey only breed in clean water, Lucero said. Its pollen has been found in sediment cores of several Mayan reservoirs. The water lily symbolized “classic Mayan kingship,” Lucero wrote.
“The kings also wore headdresses decorated with flowers, and they are depicted with water lilies in Mayan art,” Lucero said.
“Water lilies are intolerant of acidic conditions, excess calcium, such as limestone, and high concentrations of certain minerals, such as iron and manganese,” she writes.
To keep the lily pads alive, water managers would have had to line the reservoir with clay, Lucero said. Plant roots require a layer of sediment. Next, water lilies, trees, and shrubs planted near the reservoir covered the water surface, cooling the water and suppressing algae growth.
“The Maya generally did not build their homes near the edges of reservoirs, so pollution seeping through karst terrain would not have been a problem,” Lucero wrote.
Lessons from Mayan Reservoirs for the Modern Age
Lucero said evidence collected from several southern lowland cities shows that Mayan reservoirs were built as wetlands to provide drinking water to people for more than 1,000 years, and that the region was built between 800 and 900 AD. He said the results showed that it only stopped working during the most severe droughts. She points out that current climate trends will require many of the same approaches taken by the Maya, such as the use of aquatic plants to naturally improve and maintain water quality.
“Constructed wetlands have many advantages over traditional wastewater treatment systems,” she writes. “We offer processing techniques that are economical, low technology, low cost and highly energy efficient.”
Constructed wetlands not only provide clean water, but can also be a source of nutrients to feed aquatic animals and replenish agricultural soils, she wrote. “The next step moving forward is to combine our respective expertise and put into practice the lessons embodied in ancient Mayan reservoirs, combined with what is now known about constructed wetlands.” she wrote.
References: “Ancient Maya Reservoirs, Constructed Wetlands, and Future Water Needs” by Lisa J. Lucero, October 9, 2023. Proceedings of the National Academy of Sciences.
DOI: 10.1073/pnas.2306870120
Source: scitechdaily.com