Unit 5: Agriculture and Rural Land-Use Patterns and Processes

Agriculture

Deliberate modification of Earth’s surface by cultivating plants and raising animals to produce food, fiber, fuel, and other products.

Primary economic activity (primary sector)

Economic activities that extract or harvest natural resources, including agriculture, forestry, fishing, and mining.

Intensive agriculture

Farming with high labor and/or capital inputs per unit of land, usually on relatively small plots to maximize yield per acre/hectare.

Extensive agriculture

Farming with relatively low labor input per unit of land, spread over very large areas (low inputs per acre/hectare).

Subsistence agriculture

Agriculture that produces food primarily for consumption by the farmer’s household or local community rather than for sale.

Commercial agriculture

Agriculture that produces goods primarily for sale in regional, national, or global markets; often specialized and capital-intensive.

Physiologic density

The number of people per unit of arable land (farmable land); often higher in poorer/developing countries.

Arable land

Land suitable for growing crops (cultivable farmland).

Agricultural hearth

A region where agriculture originated and from which farming practices diffused to other areas.

Neolithic Revolution (First Agricultural Revolution)

The shift from hunting and gathering to domestication of plants/animals and permanent settlement, enabling surplus and population growth.

Domestication

The selective breeding and management of plants or animals to produce desired traits for human use.

Vegetative planting

Planting method based on growing crops from shoots, stems, roots, or cuttings taken from existing plants.

Seed agriculture

Planting method based on collecting and replanting fertilized seeds (grains, fruits, etc.).

Multi-cropping

Growing more than one crop on the same plot (simultaneously or in sequence) to reduce risk and/or increase output.

Monoculture

Cultivating a single crop over a large area; can increase efficiency but may increase vulnerability to pests/disease and reduce biodiversity.

Animal husbandry

The purposeful interbreeding/management of domesticated animals to strengthen desired traits and increase production.

Relocation diffusion

Spread of a practice through the movement of people who carry crops/animals/knowledge to new places.

Expansion diffusion

Spread outward from an origin while the origin remains strong; adoption increases across space.

Columbian Exchange

The transoceanic transfer of crops, animals, and diseases between the Americas and the Old World after European colonization (e.g., maize outward, wheat into the Americas).

Second Agricultural Revolution

Agricultural changes tied to industrialization that increased production through improved methods, chemistry, mechanization, and transport links to markets.

Mechanization

Use of machines (e.g., tractors, pumps, trucks) to replace human/animal labor and increase farming efficiency.

Artificial fertilizers

Industrial chemical fertilizers that replace nutrients (especially nitrogen) in soils to boost crop yields.

Pesticides

Chemicals used to control pests and diseases affecting crops (including insecticides, herbicides, fungicides, etc.).

Green Revolution

Mid-20th-century yield increases from adopting high-yield seeds plus inputs such as irrigation, fertilizers, and pesticides; benefits and costs were uneven.

High-yield varieties (HYVs)

Crop varieties bred to produce greater yields, often requiring reliable water, fertilizer, and pest control to reach full potential.

Agribusiness (corporate agriculture)

The industries and firms involved in commercial food production, including farming plus processing, packaging, distribution, marketing, and retail.

Commodity chain (value chain)

The linked network of inputs, production, processing, distribution, and consumption that brings an agricultural product to consumers.

Genetic modification (GM)

Altering an organism’s genetic material to create desired traits (e.g., pest resistance or herbicide tolerance).

Shifting cultivation (slash-and-burn)

Subsistence farming system in which land is cleared (often burned), cultivated for a few years, then left fallow while farmers move to a new plot.

Fallow

A period when farmland is left uncultivated to restore soil fertility and allow vegetation regrowth.

Pastoral nomadism

Subsistence strategy based on herding domesticated animals and moving seasonally to access water and pasture in arid/semi-arid regions.

Transhumance

Seasonal movement of herds between pastures (often higher in summer, lower in winter) to follow grazing opportunities and avoid harsh conditions.

Ranching

Commercial grazing of livestock over a large area, typically extensive; can cause overgrazing if stocking rates exceed land capacity.

Wet rice (paddy cultivation)

Growing rice in flooded fields; often highly productive and common in densely populated regions with intensive labor inputs.

Terracing

Cutting step-like flat surfaces into hillsides to expand arable land and reduce erosion by slowing water runoff.

Plantation

Large-scale commercial farm specializing in one or a few cash crops for sale (often global export), typically using wage labor and monoculture.

Mixed crop and livestock farming (mixed farming)

Farming system combining crops and animals on the same farm; crops can feed animals and manure fertilizes fields, spreading economic risk.

Crop rotation

Planting different crops on the same field in different years to maintain soil fertility and disrupt pest cycles.

Irrigation

Artificially supplying water to crops to increase yields or farm in dry climates; can create sustainability problems (water depletion, salinization).

Aquifer

Underground water storage (water table) that can be tapped for irrigation; can be rapidly depleted when withdrawal exceeds recharge.

Soil salinization

Salt buildup in soil, often linked to irrigation in hot/dry climates where evaporation leaves minerals behind, reducing crop productivity.

Township and range (rectangular survey system)

Grid-based land division system (U.S. Public Land Survey System) that creates rectangular parcels and checkerboard landscapes efficient for mechanized farming.

von Thünen model

Agricultural location theory explaining land-use patterns around a central market based on transportation costs and land rent.

Land rent

The amount a producer can afford to pay for land; generally declines with distance from the market as transport costs rise.

Land tenure

The legal/customary rights people have to land; affects investment incentives, access to credit (collateral), and vulnerability to eviction.

Food security

A condition in which people have reliable access to sufficient, safe, nutritious food; depends on access and distribution, not just production.

Desertification

Land degradation in drylands caused by climate variability and human activities (often including overgrazing), reducing long-term productivity.

Conservation agriculture

Sustainable farming approach that maintains production while protecting resources (e.g., no-till, crop rotation, inter-planting).

Sustainable yield

The amount of crops or livestock that can be produced without endangering local resources (soil, water, groundwater) or making farming economically unviable.

Food desert

An area where residents have limited access to affordable, nutritious food (especially fresh produce), often due to income and transportation/retail geography.