Food Production and Agriculture

How to Feed a Hungry Planet 1. Three systems provide most of the world’s food & uses 40% of the world’s food a. Cropland: produces grains; provides 77% of world’s food on 11% of the land b. Rangeland, pastures, feedlots: produce meat, 16% of world’s food on 29% of land c. Fisheries: supply 7% of world’s food Where do most of the people live relative to the type of land the country has?

Depending on too Few Species 1. 50,00 edible plant species species supply ~ 90% of the world’s food calories 3. Rice, wheat, and corn supply 48% of calories that people consume directly  2/3 of world’s people survive on these 3 grains 4. Few species of mammals and fish provides world’s meat & seafood 5. Violation of Biodiversity principle of sustainability  Depending on so few species puts people at risk in times of food scarcity (EX: Irish Potato Famine) “Corn” laws in Britain were main cause of Irish Potato Famine. Irish could not afford grain, grew potatoes, potatoes rotted, & Irish starved.

Monoculture Crops 1. Monoculture: growing a single crop or just a few crops in a single area 2. Term also applied if only raising one species of livestock or fish a. EX: a 40 acre field of corn planted next to a 40 acre field of soybeans b. Disadvantages:  Usually requires a higher input of fertilizer, pesticide, financial capital, etc to maintain  lack of genetic diversity within each field  EX: Irish grew potatoes; all the plants were clones (genetically identical) and none were resistant to the late blight fungus Monoculture: Canola field

Polyculture Crops 1. Polyculture: growing many crops on the same plot of land simultaneously 2. Term also applied if you are raising livestock or fish a. Advantages:  Maintains more natural environments for predators to help rid crops of pests  increased genetic diversity; usually don’t lose all crops if bad weather, pests, or disease sets in b. Disadvantages:  Can be more labor intensive

Industrialized Agriculture 1. Uses heavy equipment and large amounts of financial capital, fossil fuels, water, commercial inorganic fertilizers and pesticides 2. Produces single crops (Monoculture) 3. Major goal is to steadily improve each crop’s yield Practiced on ¼ of all cropland, mostly in developed countries. Produces 80% of world’s food

Plantation Agriculture 1. Used Mostly in less-developed tropical countries 2. Involves growing cash crops such as bananas, soybeans, sugar cane, tea, coffee, palm oil, and vegetables Tea plantation in Malaysia Plantation crops are grown mostly for export to more developed countries

Greenhouse Agriculture 1.Raise crops indoors 2.Used in Iceland and some western states in US; heated with geothermal energy 3.Uses less water than irrigation, so they work well in arid regions 4.Water can be purified and recycled; water use and pollution are minimal

Modern Industrialized Agriculture & Sustainability 1. Violates 3 Principles of Sustainability a. Relies heavily on nonrenewable fossil fuels b. Does not rely on a diversity of crops as ecological insurance  Ricky; easy to lose all of your crop due to drought, flood, pests, disease, etc c. Neglects the conservation and recycling of nutrients in topsoil

Hydroponics 1. Hydroponics: growing plants without soil but you can use a growth medium such as sand or vermiculite 2. Plants are grown indoors; can be grown anywhere 3.. Advantages:  Plants are watered with a nutrient rich water adjusted at the proper pH  Increased crop yields b/c plants are grown year round  No runoff of fertilizer  No pesticides 4. Disadvantage:  Expensive to start

Traditional Subsistence Agriculture 1.Relies heavily on animal and human labor 2.Produce enough crop to feed family; little left over to sell or store for later

Traditional Intensive Agriculture 1. Farmers increase human and animal labor, fertilizer, and water to produce more food per acre 2. Goal is to produce enough food to sustain family AND sell some for a profit

Slash and Burn Agriculture 1. Type of subsistence agriculture  Burn small plots of tropical forests  Grow a variety of crops for a few years until soil is depleted of nutrients  Takes years for soil to recover to be used again 2. Disadvantages  Tropical rain forests are nutrient poor; have to cut down another patch in a few years  Many poor are moving out of cities and into rainforest  Losing much of our biodiversity; rainforests contain about 50% of all species but they only cover 7% of total land

Green Revolution 1. Term used to describe the transformation in agricultural practices in many parts of the developing world between 1940 and the 1960s 2. Goal: to eradicate famine in many nations and massively increase food production 3. Idea was to transplant many of the systems, ideas and technology of Western farming into (mainly) Asian agriculture 4. One of the biggest improvements made within the Green revolution was seed selection of plants with the best properties to fit certain environments 3 Steps 1.Develop high yield plant monocultures 2.Produce high yields by using large inputs of water, fertilizer, & pesticides 3.Increase number of crops grown per year (double cropping)

The Green Revolution

Agribusiness 1. The market segment dealing with the art, science, and industry of feed and grain handling and processing. 2. Giant multinational corporations that control the growing, processing, distribution, and sale of food in the US and global markets

CAFOs 1. Concentrated animal feeding operations 2. animals are kept and raised in confined situations 3. congregate animals, feed, manure and urine, dead animals, and production operations on a small land area. 4. Disadvantages  Animals are often given growth hormones to help them grow more quickly; growth hormone is passed on to human consumers  Animals also given antibiotics to keep them healthy; antibiotics passed on to human consumers

Aquaculture 1. About 1 billion people depend on seafood as their main source of protein 2. Almost half of the seafood we eat comes from farms 3. When done responsibly, aquaculture’s impact on wild fish populations, marine habitats, water quality and society can be significantly and measurably reduced Disadvantages:  Farmed fish contain lice and diseases that can spread to wild fish if they escape into the open water  Excess fish food and waste in the water lead to hypoxia in oceans  Farmed raised fish can escape and interbreed with wild, natives and alter the gene pool

Human Impact of Industrialized Agriculture

THE GREEN REVOLUTION AND ITS ENVIRONMENTAL IMPACT 1. Modern agriculture has a greater harmful environmental impact than any human activity. Loss of a variety of genetically different crop and livestock strains might limit raw material needed for future green and gene revolutions. –In the U.S., 97% of the food plant varieties available in the 1940 no longer exist in large quantities.

Erosion of Topsoil 1. Soil erosion: movement of soil components, surface litter & topsoil by wind or water 2. Plant roots keep soil in place; remove plants & soil is carried away 3. Flowing water is largest cause of erosion; also carries fertilizer and pesticides into aquatic ecosystems 4. Lose of soil fertility through depletion of plant nutrients; violates earth’s chemical cycling principle of sustainability Soil erosion in Washington state Soil erosion occurs faster than soil is replaced on 38% of world’s cropland

Soil Erosion in the US billion tons of soils are eroded from the U.S. each year; this would fill 320 million average-sized dump trucks that, if parked end-to-end, would extend to the moon and ¾ of the way back! 2.Soil erosion lowers soil fertility and can overload nearby bodies of water with eroded sediment. –Sheet erosion: surface water or wind peel off thin layers of soil. –Rill erosion: fast-flowing little rivulets of surface water make small channels. –Gully erosion: fast-flowing water join together to cut wider and deeper ditches or gullies

Desertification 1. Growing crops or raising livestock (pasture / rangeland) on arid /semi- arid land or raising has accelerated desertification 2. Occurs when there is a loss 10% or more of topsoil or prolonged drought

Water Deficient Through Irrigation 1. Using groundwater faster than it is replenished results in:  Aquifer depletion  Lowering of the water table  Aquifer subsidence  Saltwater intrusion

Salinization and Waterlogging Repeated irrigation can reduce crop yields by causing salt buildup in the soil and waterlogging of crop plants.

Fig , p. 281 Evaporation Transpiration Evaporation Waterlogging Salinization Waterlogging 1. Irrigation water contains small amounts of dissolved salts 2. Evaporation and transpiration leave salts behind. 3. Salt builds up in soil. 1. Precipitation and irrigation water percolate downward. 2. Water table rises. Less permeable clay layer

Fig , p. 281 Cleanup Prevention Soil Salinization Solutions Reduce irrigation Switch to salt- tolerant crops (such as barley, cotton, sugarbeet) Flush soil (expensive and wastes water) Stop growing crops for 2–5 years Install underground drainage systems (expensive)

Salinization and Waterlogging of Soils: A Downside of Irrigation Example of high evaporation, poor drainage, and severe salinization. White alkaline salts have displaced cops. Figure 13-14

Fig , p. 285 Biodiversity LossSoil Water Air PollutionHuman Health Loss and degradation of grasslands, forests, and wetlands Erosion Water waste Greenhouse gas emissions from fossil fuel use Nitrates in drinking water Loss of fertility Aquifer depletion Pesticide residues in drinking water, food, and air Salinization Increased runoff and flooding from cleared land Other air pollutants from fossil fuel use Fish kills from pesticide runoff Waterlogging Sediment pollution from erosion Greenhouse gas emissions of nitrous oxide from use of inorganic fertilizers Contamination of drinking and swimming water with disease organisms from livestock wastes Desertification Killing wild predators to protect livestock Fish kills from pesticide runoff Surface and groundwater pollution from pesticides and fertilizers Belching of the greenhouse gas methane by cattle Loss of genetic diversity of wild crop strains replaced by monoculture strains Bacterial contamination of meat Overfertilization of lakes and rivers from runoff of fertilizers, livestock wastes, and food processing wastes Pollution from pesticide sprays

CATCHING AND RAISING MORE FISH AND SHELLFISH After spectacular increases, the world’s total and per capita marine and freshwater fish and shellfish catches have leveled off.

CATCHING AND RAISING MORE FISH AND SHELLFISH 1. Government subsidies given to the fishing industry are a major cause of overfishing. –Global fishing industry spends about $25 billion per year more than its catch is worth. –Without subsidies many fishing fleets would have to go out of business. –Subsidies allow excess fishing with some keeping their jobs longer with making less money.

Fig , p. 292 Trade-Offs Aquaculture AdvantagesDisadvantages High efficiencyNeeds large inputs of land, feed, and water High yield in small volume of water Large waste output Destroys mangrove forests and estuaries Can reduce overharvesting of conventional fisheries Uses grain to feed some species Low fuel use Dense populations vulnerable to disease Tanks too contaminated to use after about 5 years High profits Profits not tied to price of oil

Fig , p. 293 Solutions More Sustainable Aquaculture Use less fishmeal feed to reduce depletion of other fish Improve management of aquaculture wastes Reduce escape of aquaculture species into the wild Restrict location of fish farms to reduce loss of mangrove forests and estuaries Farm some aquaculture species in deeply submerged cages to protect them from wave action and predators and allow dilution of wastes into the ocean Certify sustainable forms of aquaculture