Glenn D. Stone (1991) Settlement Ethnoarchaeology: Changing Patterns among the Kofyar of Nigeria. Expedition 33(1) : 16-23.
Intensive Farming
At the heart of most discussions of traditional farming systems is a broad theory published by Ester Boserup, a Danish agricultural economist, in a 1965 book entitled On the Conditions of Agricultural Growth. In contrast to Malthus's famous pessimistic essay, in which population growth is forever limited by agricultural productivity, Boserup sees population growth as the major cause of increasing agricultural productivity. But increases in productivity exact disproportionate increases in human labor.Boserup classifies traditional farming systems on a scale ranging from extensive to intensive. Extensive agriculture is relatively easy. In its most common form, called slash-and-burn, trees in primary or old secondary forests are cut and burned, and crops are planted in the ashes. After only a few years, the field is left to regenerate. At any given time, there will be more land in fallow than in cultivation. This can be a highly productive method of farming that requires minimal effort in field preparation and crop tending. The problem with extensive farming is that it requires an abundance of farmland, and when population density rises, agricultural techniques must change.
When the acreage per person shrinks, farmers must start to cultivate plots that have been fallowed for shorter and shorter periods. These plots tend to be less fertile, and often are covered by grasses or bushes rather than forest. Therefore field preparation becomes a larger job (often leading to adoption of plowing) and methods of fertilizing and irrigation may become necessary. The process of working harder and harder on less and less land is agricultural intensification. The linchpin of Boserup's theory is that the higher the rural population density, the more hours the farmer must work for the same amount of produce. There are, in other words, diminishing returns. This is why farmers tend to intensify their agriculture only when they have to.
Boserup's work has had a major impact on archaeology, andarchaeologists have proposed several adjustments and refinements of the model. One important point is been the issue of abandonment. Boserup makes the "idealizing" assumption that farmers cannot simply move to a new location, and they therefore invariably intensify when population rises. Some archaeologists have taken the position that, faced with the prospect of intensifying, farmers who can leave invariably do leave. The Kofyar data allow us to move beyond these assumptions and begin to isolate factors which shape this important aspect of farming settlement.