As climate change intensifies, the Andean highlands of Peru are transforming into an arid region, reshaping the livelihoods of farmers and habitants alike. Tropical glaciers, like the Ausangate, are retreating, and the people living at the foothills of these glaciers are losing access to clean water, essential for drinking and irrigating crops and pastures.
"If the snow disappears, the people will disappear too," says Rev. Antonio Sánchez-Guardamino, a priest in the country’s southern Ocongate District. He continues, "if the snow disappears, we will be left without water. The pastures and the animals will disappear. Everything is interconnected. The problem of the melting of the glaciers is that the source of life is drying up."
Food insecurity is a persisting problem in the rural Andes, where many smallholder farmers produce staple crops at a subsistence level. The necessity to care beyond oneself and one’s family, for the alpacas and llamas at the core of the Peruvian culture and economy, has been a more difficult task to uphold. And as water in the lower regions of the mountains grows scarce, farmers must move uphill, where water is more abundant but the land is more scarce, leaving less room for crops, pasture, and living.
In order to effectively and sustainably handle these persisting issues, the Peruvian people have turned to ancient agricultural technologies that have existed since long before the time of the Incas. That being said, three ancient technologies that are helping alleviate food and water insecurity in the Peruvian Andes are amunas, terraces, and waru warus.
Amunas, put simply, turn rainwater into drinking water. 1,400 years ago, indigenous communities on the slopes of the Andes dug stone-lined canal systems—amunas—to channel excess rainwater to areas where the ground could absorb more water. From there, the water trickled through sediment and cracks in the rock until reaching the springs downslope as fresh drinking and irrigation water. Today, most of these once-widespread canals lie abandoned or clogged, but eleven of the original canals still function, feeding 65 active springs and 14 small ponds. More restoration work is being done as well.
While amunas focus on making water more accessible, terracing makes farming on the highlands a more fruitful feat, and is quite a common agricultural practice in the Andes. Conventional farming calls upon the removal of trees and plants to be replaced with crops such as potatoes and corn. However, this kind of farming is ineffective on the steep Andean slopes, as it causes erosion and landslides, simultaneously turning the soil less fertile for crops to grow. Terraces on the other hand turn these slopes into leveled, benched out steps for crop roots to evenly penetrate, with sustainable water drainage systems, allowing un-farmable foothills to become stable and productive farmlands.
Most terraces that are being used today had been created many years ago, during Huarpa, Wari, and Incan times. As scientists and engineers have investigated these ageless feats of technology, they have deconstructed the immense level of difficulty ancient inhabitants went through when engineering these devices. From that, they had discovered that the first step in constructing a terrace was to lay an underground foundation to aid in stabilizing the retaining wall above the slope of the ground. Behind the retaining wall, the ground was filled with large stones overlaid by a thick layer of sand or gravel. Capping the terrace was a layer of topsoil, resulting in rich, well-drained soil and a level surface to grow crops.
Combining a bit of amuna with a bit of terrace results in waru waru, which is used to irrigate crops and store water. This system, which is a combination of raised beds and irrigation channels, is an inexpensive way to improve crop yields and mitigate the punishing effects of farming at 12,500 feet above sea level. Alipio Canahua, an agronomist working with the FAO, says that this system, “captures water when there are droughts and drains away water when there’s too much rain, meaning that it irrigates the crops all year round.” This is imperative, as the weather of Peru has only gotten more unpredictable in time due to the changing climate. Not only that, but waru warus trap the heat that is stored in water during the day and release it at night, which is crucial in preventing crop failure due to frost, a common occurrence during the nights on the highlands.
While the effects of climate change are visibly affecting Peruvian livelihoods for the worse, the resilience of a people who rely on the steadfast nature of the mountains is coming into its full power. The necessity to adapt, educate, and overcome one of Earth’s many obstacles prevails in times of dire need, and with adaptation comes technology—in the Andes, a growing return and revamping of ancient amunas, terraces, and waru warus.
Works Cited
Fraser, B. (2009, October 5). Climate Change Equals Culture Change in the Andes. Scientific American.
Giamberso, L. R. (2014). Climate Change and Peruvian Potato Farming: Traditional Knowledge in Climate Change Adaptation (Unpublished master's thesis). Robert D. Clark Honors College. Retrieved May 26, 2020, from http://andes.center/wp-content/uploads/2018/07/36692398-1.pdf
Kenny, A. (2015, November 17). Inside Peru's Coming Green Water Revolution. Retrieved May 26, 2020, from https://www.ecosystemmarketplace.com/articles/inside-perus-coming-green-water-revolution-2/
Levy, E. (2019, June 29). What Is Terrace Farming? Retrieved May 26, 2020, from https://www.earth.com/earthpedia-articles/what-is-terrace-farming/
Middle Horizon. (n.d.). Retrieved July 07, 2020, from http://www.unm.edu/~gbawden/324-Wari/324-Wari.htm
Peru. (n.d.). Retrieved May 26, 2020, from https://www.choicehumanitarian.org/peru
Raised beds and waru waru cultivation. (n.d.). Retrieved May 26, 2020, from http://www.oas.org/DSD/publications/Unit/oea59e/ch27.htm
Smith, K. N. (2019, June 24). Ancient Peruvian engineering could help solve modern water shortages. Retrieved May 26, 2020, from https://arstechnica.com/science/2019/06/ancient-peruvian-engineering-could-help-solve-modern-water-shortages/
The three wonders of the ancient world solving modern water problems. (2015, August 20). Retrieved May 26, 2020, from http://www.kleanindustries.com/s/environmental_market_industry_news.asp?ReportID=720079
