AGRICULTUREBy Megan Keane, Ally Reis, Lizzy McArthur, and Melissa Vitti

The History of Agriculture• Agriculture- practice of raising crops

and livestock for human use and consumption

• Agriculture arose 10,000 years ago– Fertile crescent

• Gradual transition from hunter-gatherer to agricultural societies

• Hunter-gatherers collected wild plants• Eventually people began consciously

guiding artificial selection

Traditional Agriculture

• Biologically powered agriculture– Harvesting of crops was done with man power

and animal muscle

• Subsistence agriculture- farming families only produced enough for themselves

• Intensive traditional agriculture- Produce excess food to sell

Industrialized Agriculture• Farmers replace animals with faster more

powerful means of harvesting crops • Boosts yield by intensifying irrigation and

synthetic fertilizers• Chemical pesticides reduce pests• Plants monocultures- uniform planting of a

single crop

Plantation Agriculture• Plantation agriculture is a form of large-scale farming • Produces one or two crops and livestock for sale• Contributing to the macro-economies in many countries

– Provides employment• Soil fertility at many plantations is affected by continuous

crop cultivation

Slash & Burn Agriculture

• Cutting and burning of forests or woodlands to create fields for agriculture or pasture for livestock

• Plots are cultivated for a few seasons and then abandoned as fertility declines and pests invade

• Sometimes there are several cycles of slash-and-burn within a few years time span

• Large scale erosion can occur

Sustainable Agriculture• Three main goals-

environmental health, economic profitability, and social and economic equity• Produce crops without causing

severe damage to ecosystem

• Methods: – Crop Rotation– Contour farming– Terracing– Intercropping– Shelterbelts– No-till farming

Organic Agriculture

• Organic agriculture- Relies on sustainable agriculture methods to maintain soil productivity and control pests– excludes or limits synthetic fertilizers and pesticides,

livestock feed additives, and genetically modified organisms

• ‘Organic’ is a term that the production of produce uses materials and practices that enhance the ecological balance of natural systems and that integrate the parts of the farming system into an ecological whole

• Many local farms produce organic products and support of these farms is growing

Agriculture Land Use• Cropland- land used to raise

plants for human use• Rangelands & pastures- land

used for grazing livestock– Undergrazing- Too few animals

being kept in a habitat, or for too short a period

– Overgrazing- Too many animals eat too much plant cover

• Impends plant growth and the replacement of biomass

• Soil is vulnerable to erosion• Compact and alter soil structure

Rangeland Management

• Managers asses the carrying capacity before use

• Herds are rotated from site to site• Enforced limits on grazing on public land

Bureau of Land Bureau of Land ManagementManagement

Nation’s single largest land ownerNation’s single largest land owner

Owns 106 million ha (261 million acres) in 12 Owns 106 million ha (261 million acres) in 12 western stateswestern states

Ranchers in these states graze their cattle on Ranchers in these states graze their cattle on the bureau’s land for inexpensive fees. the bureau’s land for inexpensive fees. Unfortunately, the inexpensiveness Unfortunately, the inexpensiveness encourages overgrazing which can be encourages overgrazing which can be damaging to the soil.damaging to the soil.

Advantages of Feedlot Advantages of Feedlot AgricultureAgriculture

Delivers energy rich food Delivers energy rich food to animals at high to animals at high densities, this creates a densities, this creates a greater level of greater level of production of food.production of food.

The movement of grazing The movement of grazing animals away from animals away from grassland reduces the grassland reduces the negative impacts that the negative impacts that the animals typically have on animals typically have on the soil. By moving the the soil. By moving the animals to a facility where animals to a facility where they are fed, they are not they are fed, they are not polluting or overgrazing polluting or overgrazing the grasslands as much the grasslands as much as they would if raised in as they would if raised in the wild.the wild.

Disadvantages of Disadvantages of Feedlot AgricultureFeedlot Agriculture

Waste containment is a massive problem for Waste containment is a massive problem for feedlots, the excess waste from the animals can feedlots, the excess waste from the animals can often end up polluting groundwater and surface often end up polluting groundwater and surface water. Events such as this have occurred in North water. Events such as this have occurred in North Carolina, Maryland and other states and have lead Carolina, Maryland and other states and have lead to outbreaks of disease.to outbreaks of disease.

One dairy cow can produce 20,400 kg of waste in a One dairy cow can produce 20,400 kg of waste in a single year.single year.

The excess grain that the animals are fed and the The excess grain that the animals are fed and the steroids they are injected with to keep them bigger steroids they are injected with to keep them bigger and “healthier” which only creates more waste.and “healthier” which only creates more waste.

More DisadvantagesMore Disadvantages

Antibiotics are also used in Antibiotics are also used in excess at feedlots, as the excess at feedlots, as the antibiotics move through antibiotics move through the food chain they can lead the food chain they can lead the microbes to evolve the microbes to evolve resistance to them.resistance to them.

The mistreatment of feedlot The mistreatment of feedlot animals, though seemingly animals, though seemingly less important than the less important than the negative environmental negative environmental effects, is still an prominent effects, is still an prominent issue. The animals are kept issue. The animals are kept in very close quarters, which in very close quarters, which can contribute to the spread can contribute to the spread of disease (thus the excess of disease (thus the excess antibiotics). Often chickens antibiotics). Often chickens are kept in tiny cages are kept in tiny cages together and are de-beaked.together and are de-beaked.

Energy EfficiencyEnergy Efficiency

Every time energy is moved from one trophic Every time energy is moved from one trophic level to the next, as much as 90% is lost.level to the next, as much as 90% is lost.

Cows use up energy as they convert grain into Cows use up energy as they convert grain into tissue, therefore eating meat is far less energy tissue, therefore eating meat is far less energy efficient than relying on a vegetarian diet.efficient than relying on a vegetarian diet.

The lower in the food chain that we get our food, The lower in the food chain that we get our food, the higher the energythe higher the energy

Earth could support more people if everyone ate Earth could support more people if everyone ate food from low on the food chain because that food from low on the food chain because that would increase the proportion of the sun’s energy would increase the proportion of the sun’s energy that we put to use as food.that we put to use as food.

LandLand

In 1900 we fed about 10% of our global grain In 1900 we fed about 10% of our global grain production to animals. In 1950 the number went up to production to animals. In 1950 the number went up to 20%, by the beginning of the 2120%, by the beginning of the 21stst century we were century we were feeding 45% of our global grain production to animals.feeding 45% of our global grain production to animals.

Producing eggs and chicken meat requires the least Producing eggs and chicken meat requires the least amount of land (22 m^2 for eggs and 14 m^2 for amount of land (22 m^2 for eggs and 14 m^2 for chicken meat), whereas beef requires the most (245 chicken meat), whereas beef requires the most (245 m^2)m^2)

One increasingly popular solution to the land problem One increasingly popular solution to the land problem is to feed the livestock crop residues, plant matter that is to feed the livestock crop residues, plant matter that we would not consume anyway such as stalks and we would not consume anyway such as stalks and stems.stems.

Government Agricultural Policies

Agriculture in many countries is supported by billions of dollars in government subsidies

Roughly one-fifth of the income of the average U.S. or Canadian farmer comes from subsidies

The government keeps commodity prices low

Agricultural Risk Protection Act (ARPA) of 2000 increased premium subsidies

What has allowed us to produce more food per person in the past?

Fertilizers boost crop yields but can be over applied

Inorganic fertilizers are often synthesized using the Haber-Bosch process– Haber process produces ammonia which can be

used in the production of nitrogen fertilizer– Haber process produces 100 million tons of

nitrogen fertilizer per year which is responsible for sustaining one-third of the Earth’s population

What has allowed us to produce more food per person in the past?

Organic fertilizers– Green manure

Type of cover crop grown primarily to add nutrients and organic matter to the soil (improves and protects soil)

Increase the percentage of biomass in the soil and improves water retention, aeration, and other soil characteristics.

– Compost Combination of decomposed plant, animal and other organic

materials being decomposed into a rich soil Beneficial for the land

– Soil conditioner, fertilizer, natural pesticide for soil Provides the support and nutrients needed so plants can

flourish– Spores

Form part of the life cycles of many plants

The First Green Revolution Started in the 1960’s Concentrated effort in traditional plant breeding New strains of wheat, corn, and rice developed and were introduced in third

world countries, along with chemical fertilizers, and resulted in increases in yields

Allowed food production to keep pace with worldwide population growth Benefited many countries

– Mexico used to import but this made them self-sufficient and their corn production had tripled

– India’s grain harvest grew by 50% Negative impact: only delayed the consequences, didn’t solve the problem Green Revolution crops required extensive technology for planting, irrigation,

fertilizing, spraying, and harvesting– Only a minority of third world farmers could afford the machines and chemicals

needed

The Second Green Revolution

A second Green Revolution is needed Investment in new technology, innovation, and farm

infrastructure will be necessary Scientists are developing new crop protection, plant breeding

and plant biotechnology solutions to help increase farm yields throughout the world

Also trying to produce crops, such as cotton, rice and corn, that are stress-tolerant and produce higher yields

New methods to feed more people in the future…

“New” FoodsWinged Bean- A pea-like bean that is found in Asia

that grows vigorously in short days (summer and fall) The most important crop in underdeveloped countries. A pound costs $46.00

Microlivestock- species that are inherently small even for animals like sheep, goats, and pigs tend to be half the size of the animals we think of. Will become very prosperous in underdeveloped countries with scarce amounts of land

Genetically Modified Organisms (GMOs)

Pros You can have stronger and

more human friendly organisms Naturally immune to pests Undesired plants are

extinguished by the plants you want

More efficient use of land Better texture Longer shelf life Less herbicides and chemicals Essential if we need to feed the

world

Cons Medical side effects Agriculture is already too

technological Only providing luxury riches

won’t feed the whole Third World

Better ways to improve land and food without chemicals

Debate over GM that doesn’t involve science

Economic caseIf we don’t keep GM food people will go abroad and

use this way of growing crops and we will lose lots of money and fall behind in the economy. We would also lose tons of jobs and people would probably move because the economy would fall because so much of our food is modified.

Democratic case With labeling, adequate protection can be given for

those who object. Several ethics and safety advisory committees represent public concerns

Precautionary Principle

An approach to environmental decision-making that structures outcomes to defeat the potentially deleterious role of uncertainty by assigning the burden of proof to the exploiter, and providing other safeguards.

The principle protects the public from exposure to harm where scientific investigation discovers a plausible risk in the course

What is food security?

Food security is an adequate, reliable, and

available food supply to all people at all times

Preserving Crop Diversity

Crop diversity provides insurance against failure because it replenishes nitrogen through green manure is sequence of cereal crops and other crops

Green manure is a cover crop that adds nutrients back to the soil.

Seed banks are storehouses for samples of the world’s crop diversity.

http://www.usda.gov/news/pubs/farmpolicy01/chapter3.pdf

oregonstate.edu/instruct/anth370/gloss.html

http://www.bayercropscience.com/bcsweb/cropprotection.nsf/id/EN_Topic_The_Second_Green_Revolution

http://www.nytimes.com/1981/10/25/magazine/the-second-green-revolution.html

http://en.wikipedia.org/wiki/Haber_process

http://www.srtp.org.uk/gmfood1.htm

http://symposia.cbc.amnh.org/archives/seascapes/glossary.html