Agriculture and Rural Land-Use Patterns and Processes

Climate and landforms shape what can be farmed: Mediterranean farmers grow grapes and olives suited to hot, dry summers, while wet rice needs warm, well-watered lowlands. Farming is intensive when a lot of labor or money goes into a small area (market gardening, plantations, mixed crop and livestock farming) and extensive when little input is spread over a lot of land (shifting cultivation, nomadic herding, ranching).

Rural settlements can be clustered (homes grouped in a village with fields around it), dispersed (farmhouses spread out, each on its own land) or linear (strung along a road, river or coast). Land has been divided in different ways. Metes and bounds uses natural features and distances, as in the original 13 colonies, while township and range lays a square grid over much of the central and western United States. Long lots, laid out by French settlers in places like Quebec and Louisiana, are narrow strips running back from a river.

Farming began independently in several hearths, the earliest known in the Fertile Crescent about 11,000 years ago (wheat, barley, sheep and goats), and later in places like the Indus River Valley, Southeast Asia and Central America (maize, beans and squash), then spread outward by diffusion. After 1492 the Columbian Exchange moved crops, animals and diseases between the Americas and the rest of the world, bringing potatoes and maize to Europe, Africa and Asia and horses and cattle to the Americas.

Starting in Britain and Western Europe in the 1700s, alongside the Industrial Revolution, the Second Agricultural Revolution brought better crop rotation, the enclosure of fields, new tools like the seed drill and later steam- and gas-powered machines, plus railroads to carry food to markets. Farms produced more with fewer workers, which fed growing cities and pushed many rural people into factory jobs.

Beginning in Mexico in the 1940s and spreading to India, Pakistan and other parts of Asia in the 1960s, the Green Revolution combined high-yield wheat and rice seeds with chemical fertilizers, pesticides, irrigation and machinery to raise crop yields sharply. It helped feed fast-growing populations, but it also increased water and chemical use, favored farmers who could afford the inputs, and had much less success in most of sub-Saharan Africa.

Subsistence farming grows food mainly to feed the farmer's own family, while commercial farming raises crops and livestock to sell, often as a monoculture (one crop covering a large area) or by monocropping (planting the same crop in a field year after year). Bid-rent theory says land closest to a market costs the most, so only uses that earn a lot per acre can afford it; that helps explain why intensive farming tends to sit near cities and extensive farming farther away.

In many more developed countries, small family farms have been bought up or merged into far fewer, much larger commercial farms, many tied to agribusiness companies that sell them seed and machinery or buy, process and ship what they grow. Economies of scale let big operations produce each unit more cheaply, and agricultural commodity chains link every step from farm to processor, shipper and store, giving a lot of power to the companies that control those steps.

Von Thünen's 1826 model predicts rings of land use around one market town: market gardening and dairy closest in, then forest for fuel and timber, then grain, and ranching farthest out, because goods that are perishable or heavy cost the most to haul. It assumes flat, even land, one market and 19th-century transport, so real patterns get bent by terrain, roads and rivers, refrigeration and specialty farming regions.

Food now moves through a global system: a banana or cup of coffee may pass through farms, processors, shippers and stores in several countries before you buy it. Many lower-income countries rely on exporting one or two crops, which leaves them exposed when world prices fall, and trade rules and government subsidies in richer countries shape what farmers everywhere can sell.

Farming reshapes the land: people clear forests (sometimes by slash-and-burn), drain wetlands, cut terraces into hillsides and irrigate dry areas. Overgrazing and overuse can lead to desertification and erosion, poorly drained irrigation can leave salt in the soil (salinization), and fertilizer, pesticide and animal-waste runoff pollutes water.

Genetically modified organisms (GMOs) can raise yields or resist pests, and major scientific reviews have found approved GM foods safe to eat, while debates continue over seed costs, corporate control and biodiversity. Other trends include aquaculture (fish farming), urban farming, community-supported agriculture, organic, local and fair trade food, all set against ongoing food insecurity and food deserts, places where fresh, healthy food is hard to reach.

Women do a large share of the world's farm work, especially in lower-income countries, where much of it is unpaid or informal: tending family plots, caring for animals and processing food. They often have less access than men to land ownership, credit, training and tools, and closing those gaps can raise harvests and improve food security.