Chinampa
The chinampa (from the Nahuatl chinamitl, in the reed fence) is an ancient Mesoamerican method of agriculture and territorial expansion that, through a kind of rafts Covered with earth, they were used to grow flowers, vegetables and fruits, as well as to expand the territory on the surface of lakes and lagoons in the Valley of Mexico; making Mexico-Tenochtitlan a floating city. They used them for agriculture and gain land from lake waters.
It is a raft, with a frame made of logs and sticks, sometimes of considerable dimensions, on which duly selected topsoil is deposited with biodegradable materials such as grass, leaves, peels of different fruits and vegetables, etc. In the chinampa, ahuejotes were planted so that their roots would grow from the water to the mainland on the banks of lagoons and streams, after the riverbed grew, they planted different crops which they later harvested.
It is a technique that began in the times of the Teotihuacan culture, although its maximum development was achieved in the 16th century. By 1519, this technique, for example, occupied almost all of Lake Xochimilco, and its combination with other techniques such as irrigation through canals and the construction of terraces, made it possible to support a very dense population.
Historical background
Agricultural techniques
At the beginning of the Late Formative it became necessary to introduce intensive forms of food production, particularly related to agriculture. In this way, the farmers took advantage of the margins of the swamps and of the concentrations of water formed during the wet season in order to obtain better irrigated and richer soils, sometimes being able to obtain three annual harvests. Also, as happened in Río Bec, they cultivated gardens around their houses -cortijos-, where they planted other plants that required more care and that diversified their diet. In the same region and in the mountains around the Caracol site, numerous hills were modified in order to contain agricultural terraces that would increase production while slowing down erosion.
However, the truly intensive nature of agriculture came hand in hand with drainage and the modifications made around the aquatic areas, giving rise to a system that has been called raised fields, very similar to the chinampas of central Mexico.
These consist of artificial concentrations of land, limited by water channels and located on the banks of rivers and swamps. With this system, a sufficient amount of well-irrigated fertile land is ensured, so that it is not necessary to fallow when working the fields, obtaining an abundant production to feed the occupants of the large urban centers. The lowlands of Belize, the Río Bec region, the banks of the Candelaria and other places had this intensive system of agriculture.
Human settlements
The minimum unit of residence of the ancient Mexicas was the house, identified by means of small mounds of earth and stones covered with clay. These constructions, no more than 0.50 m high, supported in the past rectangular huts of a perishable nature in which the peasant population lived, whether dispersed throughout the landscape or in urban centers. This housing unit can be isolated or associated with others around a patio, forming a residential complex occupied by extended families. In them, not all the buildings are houses, but there are warehouses, kitchens and residences. Several such sets are occupied by a lineage.
This is the basic settlement system of the Mayan centers, with variations in size and volume, but whose kinship ties and the specialization in the functions they played in society were a factor of cohesion and social integration. When these residential complexes reach a higher degree of complexity, with larger spaces and more elaborate buildings, small civic centers are formed, directed by local elites. These include step pyramids and large residential buildings for the leaders of the settlement.
The most complex category of settlement corresponds to the civic-ceremonial centers or cities, which socially, politically, economically and ideologically integrated large territories. They include temples, palaces, stelae, ball courts, altars, causeways, platforms, large water tanks, fortifications, arches, towers, and a wide range of buildings and ensembles, which always reproduce residential groups. The diversification in urban size and the buildings they contain, the amount of written remains and complex elements of material culture, show that some centers exercised political or economic dominance over others, the most complex being regional capitals.
News
In the lake area of the Xochimilco and Tláhuac delegation are the last remnants of Chinampas agriculture; an ancient system of wetland agriculture whose origin dates back more than 900 years, when the Nahuatl society flourished in the basin of Mexico (Rojas, 2004), and which has been named as one of the most sustainable systems ever achieved (Jiménez- Osorino et al., 1990; Ezcurra, 1991; Altieri, 2004). The Chinampas zone in the conservation land is mainly located in the agricultural area of three towns: Xochimilco, San Gregorio Atlapulco and in a scarce way in San Luis Tlaxialtemalco, place where greenhouse agriculture has replaced it.
Currently, the Chinampas area and other agricultural systems associated with lake soil have been surpassed by urbanization, becoming a huge island of traditional urban agriculture in the middle of Mexico City. In this area, a variety of vegetables and ornamental plants continue to be cultivated, productive activities have diversified, creating conditions for the development of the local economy as well as the provision of goods and services for the city (Losada, et al., 2000). Tourism, stabled cattle, backyard crops, greenhouse floriculture and Chinampas horticulture are the main activities associated with soil conservation. The goods produced in these localities are sold in food distribution centers, local markets or exported to other states of the Mexican Republic, given the fierce competition that exists in the main supply centers of the city. Another part of the production is consumed in the homes of the producers.
Associated with the agricultural area is a flooded area; effect of the constant subsidence of the lake floor, which has been transformed after several years (approximately 1990) into a seasonal and permanent wetland, in which ecological processes are carried out that have implications for the cleanliness of the city's air, removal of toxic substances from water, such as nutrients of agricultural and urban origin; as well as the promotion of habitat for a considerable amount of wild species 6 of birds, 23 of mammals, 212 of birds, 10 of reptiles, 21 of fish and 146 species of plants (Ceballos and Galindo, 1984; CONABIO, 2000) and the provision of edonic services. This area of ecological importance is located in the Ejidos de San Gregorio A. and covers an approximate area of 441 ha. The vegetation is made up of halophilous, weedy and floating species with a predominance of tule (Typha spp.), red snapper (Eichhornia crassipes) and square grass (Schoenoplectus americanus). The environmental gradient has promoted that this area presents a high environmental heterogeneity, for which a series of habitats such as tular, grassland and popal have been generated (INECOL, 2002).
The fact of being immersed in Mexico City has meant strong pressure to modify the use of land and coverage, as promoters have intervened: public policy, agriculture, organized groups in demand for housing land, the low value of agricultural land, irregular settlements, the introduction of technological packages and environmental degradation. However, it is an area that, both by official decree, by designating it a Protected Natural Area, and by the designation of Cultural Heritage of Humanity, has been protected, showing the great value that this relic of pre-Hispanic agriculture and lake ecosystem has for present and future societies.