In keeping with a brand new paper, historical Maya reservoirs, which used aquatic crops to filter and clear the water, “can function archetypes for pure, sustainable water programs to handle future water wants.”
The Maya constructed and maintained reservoirs that have been in use for greater than 1,000 years, wrote College of Illinois Urbana-Champaign anthropology professor Lisa Lucero in a perspective within the Proceedings of the Nationwide Academy of Sciences. These reservoirs offered potable water for 1000’s to tens of 1000’s of individuals in cities in the course of the annual, five-month dry season and in intervals of extended drought.
“Most main southern lowland Maya cities emerged in areas that lacked floor water however had nice agricultural soils,” Lucero stated. “They compensated by setting up reservoir programs that began small and grew in dimension and complexity.”
Over time, the Maya constructed canals, dams, sluices and berms to direct, retailer and transport water. They used quartz sand for water filtration, generally importing it from nice distances to large cities like Tikal in what’s now northern Guatemala. A sediment core from certainly one of Tikal’s reservoirs additionally discovered that zeolite sand had been utilized in its development. Earlier research have proven that this volcanic sand can filter impurities and disease-causing microbes from water. The zeolite additionally would have been imported from sources about 18 miles (30 kilometers) away.
“Tikal’s reservoirs might maintain greater than 900,000 cubic meters of water,” Lucero wrote. Estimates recommend that as much as 80,000 individuals lived within the metropolis and its environs within the Late Basic interval, roughly 600 to 800 C.E. The reservoirs saved individuals and crops hydrated in the course of the dry season, Lucero stated.
Maya royalty bought a lot of their standing from their capability to supply water to the populace.
“Clear water and political energy have been inextricably linked – as demonstrated by the truth that the biggest reservoirs have been constructed close to palaces and temples,” Lucero wrote. The kings additionally carried out ceremonies to achieve the favor of ancestors and the rain god, Chahk.
A key problem was to maintain standing water in reservoirs from changing into stagnant and undrinkable, and for that the Maya doubtless relied on aquatic crops, lots of which nonetheless populate Central American wetlands in the present day, Lucero stated. These embrace cattails, sedges, reeds and others. A few of these crops have been recognized in sediment cores from Maya reservoirs.
These crops filtered the water, lowering murkiness and absorbing nitrogen and phosphorous, Lucero stated.
“The Maya would have needed to dredge each a number of years… (and) harvest and replenish aquatic crops,” she wrote. The nutrient-laden soils and crops faraway from reservoirs might then be used to fertilize city fields and gardens.
Probably the most iconic aquatic plant related to the traditional Maya is the water lily, Nymphaea ampla, which thrives solely in clear water, Lucero stated. Its pollen has been present in sediment cores from a number of Maya reservoirs. Water lilies symbolized “Basic Maya kingship,” Lucero wrote.
“The kings even donned headdresses adorned with the flowers and are depicted with water lilies in Maya artwork,” Lucero stated.
“Water lilies don’t tolerate acidic circumstances or an excessive amount of calcium corresponding to limestone or excessive concentrations of sure minerals like iron and manganese,” she wrote.
To maintain water lilies alive, water managers would have needed to line the reservoirs with clay, Lucero stated. A layer of sediment can be wanted for crops’ roots. In flip, the water lilies and bushes and shrubs planted close to the reservoirs shaded the water, cooling it and inhibiting the expansion of algae.
“The Maya typically didn’t construct residences close to reservoir edges, so contamination seeping by way of the karstic terrain wouldn’t have been a problem,” Lucero wrote.
The proof gathered from a number of southern lowland cities signifies that, as constructed wetlands, Maya reservoirs equipped potable water to individuals for greater than 1,000 years, failing solely when the severest droughts took maintain within the area between 800 and 900 C.E., Lucero stated. She notes that present local weather tendencies would require most of the similar approaches the Maya employed, together with the usage of aquatic crops to enhance and preserve water high quality naturally.
“Constructed wetlands present many benefits over typical wastewater therapy programs,” she wrote. “They supply a cost-effective, low expertise, inexpensive and excessive energy-saving therapy expertise.”
Along with offering clear water, constructed wetlands additionally help aquatic animals and is usually a supply of vitamins to replenish agricultural soils, she wrote.
“The following step transferring ahead is to mix our respective experience and implement the teachings embodied in historical Maya reservoirs at the side of what’s presently identified about constructed wetlands,” she wrote.