Human adaptation to the high altitudes, coastal desert, and tropical jungles requires specialized knowledge and skill in addition to the physiological adjustments noted to cope with altitudinal stress. Over the course of thousands of years, people invented elaborate irrigation systems to take advantage of the potential productivity in the coastal valleys. Visitors to even the smallest coastal valleys can still find elaborate evidence of these ancient public works. Many of these networks are still in use or form the basis of rebuilt systems that provide water to the lucrative commercial agriculture now practiced. Both in prehistoric times and now, the key to social and political affairs in these and all other coastal valleys is access to water, effective irrigation technology, and the ability to keep a large labor force at the task of construction and maintenance.

The coastal valleys from colonial times to the present have been dominated by extensive systems of plantation agriculture, with powerful elite families in control of the land and water rights. The principal crops harvested under these regimes are sugarcane and cotton, with a mixture of other crops, such as grapes and citrus, also being planted. Before the Agrarian Reform Law of 1969, about 80 percent of the arable coastal land was owned by 1.7 percent of the property owners. Despite the dominance of the great coastal estates, there were, and still are, thousands of smaller farms surrounding them, producing a wide variety of food crops for the urban markets and for subsistence. Since land reform, ownership of the great plantations has been transferred to the employees and workers, who operate them as a type of cooperative. The coastal farmland is extremely valuable because of the generous climate, flat lands, and usually reliable irrigation waters, without which nothing would succeed. These advantageous conditions are supplemented by the use of excellent guano and fish-meal fertilizers. As a result, the productive coastal land, amounting to only 3.8 percent of the national total, including pasture and forest, yields a reported 50 percent of the gross agricultural product.

In the intermontane Andean valleys, there is a wide variety of farming opportunities. The best lands are those that benefit year round from the constant flow of melting glacial waters. Most farming depends on the advent of the rains, and farmers must plan their affairs accordingly. In many areas, farmers have built reservoir and canal systems, but, for the most part, they must time their planting to coincide with the capricious onset of the rainy season. Where irrigation works are operative, as on the coast, farmers are joined in water-management districts and irrigation boards, which govern water flow, canal maintenance, and enforcement of complex water rights, rules, and customs.

Over 70 percent of the smallest farms are less than five hectares in size, with the great majority of them found in the Andean highlands. A typical peasant household with such a small property cannot harvest anything but the most minimum subsistence from it 1fae t and inevitably must supplement household earnings from other sources, with most or all family members working. The adequacy of each small farm and its dispersed chacras (plots of land used for gardening) of course varies with water supply, altitude, soil fertility, and other local factors. The best irrigated farmland in the kichwa valleys tends to be highly subdivided in the competition for a rural subsistence base. The largest land holdings are the property of corporate communities, such as the numerous Peasant Communities (Comunidades Campesinas) and Peasant Groups (Grupos Campesinos). In 1990 these official forms of common entitlement, as opposed to individual private ownership, accounted for over 60 percent of pasture lands, much of which lies in the punas of the southern Andes.

The ecological mandates of the Andean environment thus structure the day-to-day farming activities of all highlanders and the character of their domestic economies. Research conducted by anthropologist Stephen B. Brush showed how peasant farmers traditionally have utilized the different ecological niches at their disposal. At the highest altitudes of production, animals are grazed and specialized tubers grown at the intermediate altitudes grains like wheat, barley, rye, and corn, as well as pulses, such as broad beans, peas, and lentils, are sown along with a wide variety of vegetables, including onions, squashes, carrots, hot rocoto peppers, and tomatoes. At still lower levels, tropical fruits and crops prosper.

Some communities have direct access to all of these production environments, whereas others may be confined to one zone only. Traditionally, the strategy of families, the basic social units of production and consumption, is to arrange access to products from the different zones through the social mechanisms available to them. Particular chacras serve as virtual chess pieces as families buy and sell property, or enter into sharecropping arrangements in order to obtain access to specific cropping areas. Marital arrangements may also be made with specific properties in mind. Thus, the system of small farms ( minifundios--see Glossary) will invariably involve a confusing but systematic pattern of holdings.

In Huaylas, Ancash Department, for example, farmers owning small but highly productive irrigated chacras at about 2,700 meters cultivate corn, vegetables, and alfalfa. Slightly higher irrigated property is devoted to grains, and higher still, chacras are devoted to potatoes, oca and other tubers, and quinoa. Above the cultivated land and on the nonirrigated hillsides, cattle and sheep are grazed on communally held open ranges and puna. In the deep protected gorges and canyons on the fringes of the district, small chacras at altitudes of 1,500 meters produce a variety of tropical crops. Consequently, within a relatively small area a single family may own or have usufruct rights to a checkerboard of small chacras, whose total area does not exceed four or five hectares, but whose range of production provides a diverse nutritional subsistence base.

For this reason, attempts to unify smallholdings to make them more efficient can likely yield the opposite effect in terms of the household economy. This is, in fact, what happened in many areas after the Agrarian Reform Law of 1969 was implemented, prohibiting sharecropping and restricting the geographical range of ownership in order to achieve hoped for economies of scale (see Glossary). After the initial attempts to enforce the new, well-meaning laws, the minifundio system began to reemerge as peasants discovered ways to circumvent its restrictions, which inadvertently limited their ownership and use of chacras to a narrow range of ecological zones (see Structures of Production , ch. 3).

In other areas, such as those described by Enrique Mayer in the Huánuco region, the relatively compressed ecology found in Huaylas gives way to one spread out over the eastern flanks of the Andes, stretching down eventually to the Selva. In contrast to the confining peasant farms of Huaylas, farmers in the Huánuco region develop barter and trade relations across the production zones, permitting them to exchange their farm produce, such as potatoes, for other crops grown at different levels.

Although most Andean farmers are independent producers, there are various types of large holdings, of which three are particularly important: the manorial estate, the minifundio and family farm, and the corporate community holding. Historically, the most significant holdings relative to socioeconomic power were the great manorial properties known as haciendas, which averaged over 1,200 hectares in size but often exceeded 20,000 hectares prior to being eliminated during the 1969-75 land reform. At the time the land reform began, 1.3 percent of the highland farm owners held over 75 percent of the farm and grazing lands, while 96 percent of the farmers held ownership of but 8.5 percent of the farm area. The corporate community holdings are in the form of land held in common title by a Peasant Community. After the land reform, groups of communities were organized as corporate bodies by the government to enable them, in theory, to combine lands and resources to gain the advantages of an economy of scale. These organizations and the Peasant Communities, reportedly numbering 5,500 in 1991, assumed titles to the haciendas expropriated during the reform period.

By contrast, the population living in the Selva is engaged in a totally different set of agroecological patterns of activity. The native peoples of the tropics, living in riverine settings for the greater part, depend on fishing, hunting, and selective gathering from the forest. They also engage in highly effective horticulture, usually in a system known as slash-and-burn (see Glossary). Long thought to be a destructive and inefficient method of farming, studies have revealed it to be quite the contrary. In this system, the tribal farmer usually exploits a particular plot for only a three-to-five-year period and then abandons it to open another fresh area. This practice allows the vegetation and thin soil to recuperate before the farmer returns to use it again in ten to twenty years. Another facet of the system is that all fields are used in a pattern of multicropping. In this approach, as many as fifteen different crops are intermingled in such a way that each plant complements the others in terms of nutrients used or returned to the soil. The arrangement also provides a disadvantageous environment for plant diseases and insect pests. Another common horticultural system employed along the river banks in the dry season takes advantage of extensive silt deposits left by the seasonal floods. On such open plots, farmers tend to monocrop or, at least, to reduce the number of varieties sown.

Data as of September 1992