Unit 3 Food: Note 2 Food Security and Agriculture Evolution
Food Insecurity: when there is no guaranteed access to food for the next meal
Chronic Hunger: when there no access to adequate food on a daily basis
Thomas Malthus: believed that the power of the population is stronger than the power in the earth to sustain humans
population grows exponentially
Green Revolution: systematic application of technological advances in agriculture
which has improved yield and crop production in less arable land, jump started Monoculture
Monoculture: single crop farming (better yield)
reduction in agrobiodiversity, more susceptible to pests and disease, requires intense use of water, energy and technology, more favorable yield
Historical Food Sustainability:
Pre 1800
Low Yield/Low Impact: 3 acres/1 person per year
1800
Moderate Yield/Moderate Impact: 2 acres/1 person per year
1900
High Yield/High Impact: 1 acre/1 person per year
2000
High Yield/High Impact: 1/3 acre/1 person per year
Summary: as of now, food production has kept up with humanity’s population growth
worldwide, grain production is enough for every human to meet a consistent 2700 calories/day intake (adults are recommended 2500 cal/day)
Where Does the Food Go?
Unevenly distributed among peoples and regions
Uneven access to arable land or farm resources
Large amount of food goes to animal production
Food Waste
Land Degradation
Technological Advances in Food Production:
Machine Power
Cultivating New Land
Increased Chemical Use
Increased Irrigation
New Varieties of Crops
Machine Power:
Major Farming Operations Use: modern tractors, tills, and drones
Advantages: allows more work to be done efficiently by fewer individual precise planting and mapping
Disadvantages: uses fossil fuels, produces pollution, expensive (low accessibility, hard to maintain), allows for tilling and other practices that may cause harm
Cultivating New Land:
Enabled by New Technology: new machinery, irrigation, terracing
Some Land is not Suite for Agriculture: when land that is not meant for agriculture is forced to yield produce through new agricultural technology, it has drastic effects on the environment of the region
Outcomes: deforestation, wetland drainage, species loss, environmental service disruption
Increased Chemical Use:
Fertilizers and Pesticides and Herbicides
Fertilizers: add nutrients into the soil that plants need to grow
allows for increases intensity of farming
Often nitrogen and phosphorus are added to soils, this means that less space is needed between plants and that farms do not have to use fallow years
Decreased crop rotation, more stress on soil and less agrobiodiversity
Nutrients are taken out of the soil faster than natural processes can replace them (creates a never ending cycle of fertilizer usage)
Disadvantages: run off from fertilizers get into surface waters like streams, rivers and creaks
These surface waters have an over abundance of dissolved nitrogen and phosphorous which causes algal blooms, groundwater contamination, and deadzones in deposition regions like deltas (ie. the Mississippi Delta)
Deadzones: massive algae that grows due to the abundance of nitrogen and phosphorus. Eventually the algae die and floods the bottom of the delta bed, releasing CO2 and depleting the amount of O2 for other marine life to live
Pesticides/Herbicides: kills plant eaters and harmful weeds
Advantages: increases crop yield
Disadvantages: direct health affects for famers, residue effects for consumers, kills desirable species (pollinators, predators of the pests, soil builders), resistant strains develop
Irrigation:
Allow water to be accessible in places where it wasn’t before
Marginal Land Use: the amount of land usable in an area with limited arable land
Irrigation increases marginal land use
However, once irrigation is introduced, the land is wholly dependent on the irrigation to be sustained
Negative Effects:
Puts pressure on already limited fresh water supply like lakes, rives/streams, and groundwater
the lower the irrigation efficiency, the greater the pressure
however the greater the irrigation efficiency, the greater the economic cost
Systems of Irrigation: efficiency is how direct water can be provided to the crops
Gravity Flow = 60% efficiency, rows of water are sat beside rows of crop, the cheapest
Center Pivot = 80-90% efficiency, a water pump and distributor are centered in a circular plot of land, median cost
Drip Irrigation = 90-95% efficiency, direct drip onto crops, highest cost
High Plain Aquifer
Used in the great plains for framing, well/groundwater is the source while center pivot is the system
Impact:
a) there is a decline in the amount of water (water is pumped out faster than it can be re-absorbed) available
b) we must remember that ground water flows, not simply stagnant
Affects of Pumps
spaces without water becomes weak, the ground collapses to fill in that gap, and water from the surface can no longer be absorbed
Climate Change
Causes less precipitation and hotter weather = longer dependency on irrigation
More dependence = decrease in water and increase of pressure on the land = possible system collapse
New Crop Varieties
Historical Breeding: hand picking and selective breeding (cross breeding) done over many generations to create new varieties
what we did for thousands of years
Modern Breeding: genetic engineering, occurring in the last 30 years
GMO: Genetically Modified Organisms
faster way to develop than selective breeding
insert genetic material from other species that would be impossible by breeding
pest and disease resistance
sweeter, larger produce
GMO Outcomes: develop/grow faster, resist some environmental stress, pest resistant, and can be chemically resistance
More yield, less irrigation needed, “round up ready crops”
GMO Impact: some but not great in the USA (4% of yield impact attributed to GMO)
Globally, countries that produce wheat, rice or in famine prone land have seen great impacts
The USA uses a lot of GMO with little impact, outside of the USA GMOs aren’t as accessible but they have more success
Health Concern: little evidence to show that GMOs are harmful to humans, the greater concern comes from the secondary impact
Round Up Ready Crops: Glyphosate is used as a herbicide that normally hurts soy, but with GMO soybeans are resistance to Glyphosate
Environment Concerns: effects the gene pool of “wild” populations
Capital Concerns: GMOs are patented and owned by multinational corps
seed saving is a normal and common practice, however since the GMO seeds are patented, it is illegal to seed save
farmers must always buy a new contract to but the seeds (monopoly)
Has lead to increased cost of farming and decrease in small family farms
high cost of seed input = smaller profit margin