The Impact of Urbanization on Agricultural Processes

The relationship between urbanization and agriculture is examined. With heavy migrations from rural to urban areas in the United States, there have been significant changes in land utilization. Land converted to urban uses is increasing, though it has little effect on total crop production. The technological transformation of agriculture has had much larger effects and has operated as a push-pull on the cityward movement of people as farm functions have moved to the city. Energy and chemical fertilizers now come from urban bases, with large numbers of urban people working for farmers. Yields per acre and per farm worker have risen sharply so that needs for agricultural products are fully met. Urbanization and rising buying power have moved Americans up the food chain. The demand for expensive animal products grows. These forces have resulted in a dramatic escalation of solid waste production in cities and on farms. Urbanization and transformed agriculture have exploded the organic matter cycle. The nitrogen thrown away in farm and urban organic wastes in the United States each year equals 137 percent of the nitrogen in all chemical fertilizers. In contrast, China keeps her organic matter cycle intact and feeds a population four times as large as ours on an equal cultivated area. Future planning must meet the challenge of wasteful land utilization, the overshift of population to cities, and the problems of restoring the organic matter cycle.