| Cities feeding people |
|Chapter 1. Introduction: african city farming from a world perspective|
Luc J.A. Mougeot
Urban agriculture (UA) encompasses the production of food and nonfood plant and tree crops and animal husbandry (livestock, fowl, fish, and so forth), both within (intra-) and fringing (peri-) built-up urban areas. Vennetier's 1958 survey of Pointe-Noire, Congo, is often credited for having launched a new field of inquiry into urban farming in sub-Saharan Africa and beyond: a sample of 1 013 households (4 493 people) enabled him to estimate that UA then was being practiced by 16 500 people (30.6% of Pointe-Noire's population), of whom 4 500 were women (Vennetier 1961, p. 84). Ganapathy (1983) later attempted a short, though very complete, definition of the concept; Smit and Nasr (1992) developed a most comprehensive worldwide farming system typology, while Sawio's dissertation (1993) thoroughly updated UA research in anglophone Africa.
As contradictory as the merging of "urban" and "agriculture" into a single expression may seem, urban agriculture as a basic urban function is nothing new. Fieldwork and aerial images of archeological sites are unraveling massive and ingenious earth and waterworks, within and fringing the larger and more advanced urban settlements achieved by ancient civilizations, for the production of food, feed, and fodder crops; fuel, building, shade, fencing, windbreak trees, and shrubs; ornamental, medicinal, and other utilitarian plants; and livestock for food, traction, transport, and savings.
Under the Persian emperor Darius, walled gardens or pairidaeze ("paradises") were associated with hydraulic facilities for maximizing the use of scarce water. Greek city-states were self-supplied with goat milk and olive-oil fuel for house lighting. Vast agricultural drainage schemes were revealed on the Roman imperial sites of Timgad in Algeria and Volubilis in Morocco. Under the Islamic empire, the Abbasids turned a postal service into an intelligence system, through which postmasters kept the capital city informed on food prices in their postal districts, so that supplies could be sent wherever shortages threatened. In Andalusian cities, houses were surrounded by gardens and orchards. Cities of the Indus River civilization, such as Harappa and Mohenjo Daro, discovered from under the shifting muds of the Indus, once were specialized agro-urban centres. In medieval Europe, crop-rotation systems were being tested in farms and fields of monasteries, walled cities, and castles.
In North America's Mississippian culture (peak 1050-1250 AD), intensive riverine horticulture supported what Burland (Coe et al. 1986, p. 57) qualifies as true preindustrial cities in the rich alluvial valleys of the Mississippi, Ohio, Tennessee, Arkansas, and Red rivers and tributaries. One of them, the city of Cahokia in Illinois, with a population of 10 000, was the largest pre-Columbian urban centre north of Mexico. Also in the middle course of the Mississippi, the Moundville site (population 3 000) in Alabama contains borrowpits evidently used to store live fish, part of the food needed to support its people (Coe et al. 1986, p. 56).
Four thousand years ago in the pre-Olmec Valley of Mexico, small towns on stone-faced terraces, such as Tlatilco and Ticoman, farmed vegetables and raised dogs and turkeys (Burland 1976, pp. 15-18). The Aztec state was partly dependent on food production within and fringing the metropolis of Teotihuacan and the capital city of Tenochtitlan, southwest of the former and on a man-made island built in Lake Mexico (Anton 1993, p.116). Millon's maps of Teotihuacan (population 125 000-250 000) clearly indicate chinampas in one section of the city: these were "rectangular plots of land left by canal-cutting in swampy areas, made fertile through periodic applications of pond weeds and mud" (Coe et al. 1986, p. 104). Highly fertile and productive chinampas were also found in Xochimilco (surviving to the present), towns on southern shores of Lake Xochimilco, and most of the island of Tenochtitlan-Tlatelolco. A 15-km-long dike, built across Lake Texcoco, protected chinampas from rising saltwater in the rainy season (Coe et al. 1986, pp. 144, 146,149). The well-spaced layout of outer house mounds probably enabled each home to have its own garden (Burland 1976, p. 40).
At Tairona's Buritaca 200 site in the Colombian Sierra Nevada, an elaborate landscape of retention walls, canals, and drainage systems afforded in-city cropping (Coe et al. 1986, pp. 166-167; Burland 1976, p. 162). In the Peruvian Andes, central plazas of U-shaped structures might have been irrigated or flooded and crops possibly grown; large ceremonial complexes were usually adjacent to cultivated fields (guinea pig remains found earlier than 1800 BC at Culebras, halfway between Trujillo and Lima) (Coe et al. 1986, p. 197). At Cuzco and Machu Picchu, extensive retention walls, terrace gravel beds and stone-lined drainage afforded intensive farming of steep slopes.
The need for reliable, minimal amounts of diverse food and nonfood supplies to ensure the subsistence and trade functions of what were then unprecedentedly large and complex human agglomerations explains the coincidence of ancient city sites with elaborate earth-and waterworks for farming. Many of these cities probably provided the incentives and testing grounds where innovations for more intensive and productive farming systems were developed, perfected, and disseminated. Technological breakthroughs included sun reflectors; water collection, storage, and distribution; frost protection; wetland conversion and slope terracing; and multicropped and layered chinampa-style systems (Reader's Digest Association, 1974, pp. 58, 76, 96, 119, 152, 154, 158, 162, 195, 198, 217).