Chinampas

Chinampa (Nahuatl: chināmitl [tʃiˈnaːmitɬ]) is a type of Mesoamerican agriculture which used small, rectangular areas of fertile arable land to grow crops on the lake beds in the Valley of Mexico.

Chinampas were created by the freshwater shoreline of the Northern portion of the central lake system of Mexico by the Nahua peoples, commonly called the Aztecs. Sometimes erroneously referred to as "floating gardens", chinampas are artificial islands that were created by building up extensions of soil into bodies of water. Evidence from Nahuatl wills from late sixteenth-century Pueblo Culhuacán suggests chinampas were measured in matl (one matl = 1.67 meters), often listed in groups of seven. One scholar has calculated the size of chinampas using Codex Vergara as a source, finding that they usually measured roughly 30 m × 2.5 m (100 ft × 10 ft). In Tenochtitlan, the chinampas ranged from 90 m × 5 m (300 ft × 20 ft) to 90 m × 10 m (300 ft × 30 ft) They were created by the shallow lake bed and then in the rectangle with wattle. The fenced-off area was then layered with mud, lake sediment, and decaying vegetation, eventually bringing it above the level of the lake. Often trees such as āhuexōtl [aːˈweːʃoːt͡ɬ] (Salix bonplandiana) (a willow) and āhuēhuētl [aːˈweːweːt͡ɬ] (Taxodium mucronatum) (a cypress) were planted at the corners to secure the chinampa. In some places, the long raised beds had ditches in between them, giving plants continuous access to water and making crops grown there independent of rainfall. Chinampas were separated by channels wide enough for a canoe to pass. These raised, well-watered beds had very high crop yields with up to 7 harvests a year. Chinampas were commonly used in pre-colonial Mexico and Central America. There is evidence that the Nahua settlement of Culhuacan, on the south side of the Ixtapalapa peninsula that divided Lake Texcoco from Lake Xochimilco, constructed the first chinampas in C.E. 1100.

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