Unit 5 APHG

Agriculture

The deliberate effort to modify a portion of Earth’s surface through the cultivation of crops and the raising of livestock for sustenance or economic gain.

Subsistence agriculture

Only enough food is cultivated to survive (no surplus to sell) and often land is held in common.

Commercial agriculture

The production of crops for sale (profit).

First Agricultural Revolution

Dating back 10,000 years, when humans achieved plant and animal domestication.

Second Agricultural Revolution

Improved methods of cultivation, harvesting, and storage of food that started in the Middle Ages and THEN benefited from the Industrial Revolution with the use of machines and new technology. Effects of Second Agricultural Revolution: - better diets - longer life expectancies - increase in population - more people available to work in factories

Green (Third Agr) Revolution

High yield seeds (hybrid and/or GMO’s), increased use of chemicals, mechanized farming, and elaborate irrigation systems. PRO’s: - increase in food supply - more crops grown on same size land - improvement in varieties - humans benefited from technology CON’s: - destroying local land and traditional modes of agriculture production - decreasing biodiversity - impact of chemicals - high cost of fertilizers, seeds, and other technology necessary

Columbian Exchange

Facilitated the global diffusion of plants, animals, diseases, human population, culture, technology, and ideas.

Carrying capacity

The maximum population size that a specific environment or agricultural system can sustainable support over time without natural resource degradation.

GMO’s

Plants or animals whose DNA has been genetically modified, often through combination of DNA from a similar plant or animal species for desired traits. PRO: - greater outputs on smaller pieces of land, less need for chemicals. CON: - unknown health effects, unknown effects on polluting insect population.

Hybridization (seeds)

The process of artificially cross-pollinating different varieties of plants to combine desirable traits.

Deforestation

Clearing of forest to make the land available for other uses (agriculture/livestock).

Desertification

Process by which fertile land becomes desert as a result of human activity. (inappropriate agriculture/overgrazing)

Shifting cultivation (slash and burn)

Clearing an area in a tropical forest for planting by burning the vegetation. - Cultivation of crops in tropical forest clearings using a natural rotation system - The forest vegetation is cleared by cutting and burning - The result is a layer of ash that contributes to the soil’s fertility - Farmer move to another parcel of land when the soil becomes fertile

Swidden

A patch of land cleared for planting through the slashing and burning of vegetation. Process: Farmers clear the land by cutting down trees and burning the debris (known as slash-and-burn agriculture). The ash provides nutrients to the soil. - Extensive form of subsistence agriculture - Primarily in tropical rainforest climate where soil nutrients are poor.

Sawah

A flooded field used for growing semi-aquatic rice. Process: Fields are levels, surrounded by dikes/bunds to hold water, and flooded. Rice seedlings grown in a nursery are then transplanted into the flooded field. - Intensive form of subsistence agriculture - Primarily in East, South, and Southeast Asia where warm climates and abundant rainfall support rice growth.

Domestication

The process by which humans cultivate and breed plants and animals for specific traits, transforming them from wild species into forms that are more beneficial and manageable for human use.

Pastoral nomadism

Pasture land that is used for animal grazing.

Double cropping

The practice of harvesting two crops (or commodities) from the same field in a single calendar year or growing season.

Mixed crop/livestock systems

Combination of cash crops and livestock to complement land and labor demands across the year.

Crop rotation

Rotating crops from one field to another, from year to year, to preserve and enhance soil fertility.