Agriculture Practices: Plant Sources

1. What Is Agriculture?

Agriculture is the activity of growing crops and raising animals for food and supplies.

Thousands of years ago, humans lived by being hunter-gatherers and traveling seasonally. This meant that they would collect whatever plant-based foods they could find and eat whatever animals they could kill. This period in human history forced populations to be low because food was sometimes difficult to find.

Eventually, the practice of growing crops and raising animals — the practice of agriculture — took hold and transformed human society. Humans transitioned to having settlements instead of traveling seasonally, thus allowing human populations to grow.

2. Green Revolution and Food Production

Agriculture then continued for thousands of years, steadily evolving until an explosion of technological advancement in the mid 1900s changed agriculture forever. This was called the Green Revolution. It allowed humans to transition from a resource-based agriculture to demand-based agriculture, meaning economics drove food production, as opposed to food production being limited by available resources.

Three primary advances allowed food production to skyrocket:

1. Improved breeding methods of crops increased plant survival and yield.
2. Mechanization of farming tools and machines improved farmers' efficiency and cut down on human labor requirements.
3. Chemical fertilizers allowed plants to get whatever nutrients they needed to grow.

The impacts of the Green Revolution are apparent when looking at the increase in grain production from 1950 to 1990. Note, in the graph below, that world grain production almost tripled worldwide in only 40 years.

Food production is dependent on four primary factors:

• Arable land, which is land suitable for crop growth
• Temperature, because certain crops and animals can only survive in certain temperature ranges
• Precipitation, because certain crops and animals can only survive with certain amounts of rainfall
• Nutrient availability, or the amount of usable nutrients in the soil for plants to consume

These combined factors determine what kinds of crops can be grown and how well they will grow.

3. Plant Sources

Let's focus on plant sources of agriculture for a moment. Corn, rice, and wheat are by far the dominant crops grown all over the world. These three crops provide over half of all human calorie needs on the planet.

There are two main categories of plant crops grown:

• Subsistence crops are food products needed for human survival.
  
  

  EXAMPLE

  Rice and corn are subsistence crops.

• Cash crops are non-food products or crops that do not make up primary nutritional needs.
  
  

  EXAMPLE

  Coffee (a food product not for primary nutrition) and latex (a non-food product grown for industrial use and economic gain) are cash crops.

terms to know

Subsistence Crops

Food products needed for survival.

Cash Crops

Non-food products or crops that do not make up primary nutritional needs.

4. Meat Sources

Meat sources are made up of animals that have been domesticated for human use. Only about a dozen large animals have been domesticated for eating. Two prime examples are chickens and sheep. The practice of aquaculture — or farming fish — is also an important part of agriculture.

There are a few important facts to know about human meat consumption:

• The developed world consumes 76% of meat compared to only 24% in the developing world, even though the developing world makes up the majority of the world's population.
• 90% of the grain grown in the U.S. is used for animal feed, which takes 16 pounds of grain to grow one pound of meat.
• U.S. citizens eat an average of 120 kilograms of meat per person every year, while their Indian counterparts eat only 4.4 kilograms.