Von Thunen Model
The ring with dairying and market gardening.
The first ring
Produces food for their own consumption.
Subsistence
Based on herding of domesticated animals. Rely on animals rather than crops
Pastoral Nomadism
When man went from hunting and gathering to the domestication of plants and animals.
First Agricultural Revolution.
Forestry
Rely on machinery to perform work.
Commerical
Farmers expend large effort to product the maximum yield from a parcel of land.
Intensive Subsistence
Increased agricultural production worldwide, particularly in developing countries.
The Third Agricultural Revolution/The Green Revolution
The ring with grain and field farming
3rd
Farmers grow crops and raise animals primarily for sale off the farm rather than their own consumption.
Commerical
Integration of crops and livestock. Most of the crops are fed to animals rather than consumed directly by humans.
Mixed Crop and Livestock
New trends in engineering, digital agriculture with a greater focus on protecting the environment.
The Fourth Agricultural Revolution
The ring with ranching and livestock
4th
More than half of the workers are engaged in farming.
Subsistence.
Farmers clear land for planting by slashing vegetation and burning the debris (slash and burn). Farmers grow crops on a cleared field for a few years until soil nutrients are depleted then leave it fallow for many years so the soil can recover.
Shifting Cultivation
The widespread transfer of plants, animals, culture, human populations, technology, diseases, and ideas between the Americas, West Africa, and the Old World in the 15th and 16th centuries.
The Columbian Exchange
The reason that garden and dairy products are in the first ring.
They have to reach the market quickly because they are perishable.
Less than one tenth of the workers are engaged directly in farming.
Commercial
Highly efficient large-scale operations. Migrant workers and experimentation with techniques keep prices low. Truck farming.
Commercial Gardening
Linked to such new agricultural practices as crop rotation, selective breeding, and a more productive use of arable land.
The Second Agricultural Revolution