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The Problem With Food, or “Where Is It All Going to Come from?” Present Case: Food production is adequate in quality and quantity to feed the current population.

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Presentation on theme: "The Problem With Food, or “Where Is It All Going to Come from?” Present Case: Food production is adequate in quality and quantity to feed the current population."— Presentation transcript:

1 The Problem With Food, or “Where Is It All Going to Come from?” Present Case: Food production is adequate in quality and quantity to feed the current population. So why are there still hungry people? Hunger is caused by two BIG problems:

2 1) Huge increases in human populations -Outstrips the local food production in many areas -Remember where population is growing the fastest? 2) An inadequate food distribution system -What causes the problems in the system? -Think Politics, Corruption, and Human Nature

3 In the FUTURE… -The capacity for increased food production will cease, and there will be limits on the available production. REMEMBER MALTHUS!!! If the population continues to grow at its current pace, it will double within the next 80-100 years. Food production would have to DOUBLE just to keep pace with population.

4 Quantity vs. Quality -As developing countries become more industrialized, the demand for higher quality foods goes up “From Rice to Steak” -At the same time, some of the best farmland is being taken out of production, and used for other purposes. Think “Houses, ethanol, and Wal-Marts”

5 How Do We Increase Production? -Historically, we would increase the amount of land that we would farm. Well, THAT’S not going to happen….. Most recently, we have increased the yield per acre farmed. But this is HARD on the environment!

6 Land available for agriculture is limited by physical and ecological considerations such as slope, floodplain, and elevation

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9 Food Crops Of 270,000 species of plants only about 3000 have been used as agricultural crops, and of those, only about 150 have been grown on a large scale. Most of the world’s food supply comes from 14 major crop plants.

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11 In Order of Importance: 1) wheat 2) rice 3) maize 4) potatoes 5) sweet potatoes 6) manioc 7) sugarcane 8) sugar beet 9) common beans 10) soybeans 11) barley 12) sorghum 13) coconuts 14) bananas

12 Location of Major Food Growing Areas Worldwide

13 Major Food Production Areas in the U.S.

14 Other Crops: Crops not intended to be eaten directly are generally called forage crops. These crops are for feeding animals such as cattle and other domestic animals. Forage crops include things like hay, alfalfa and straw.

15 Lands that are marginal for agriculture can be used for other purposes. Ex: Steeper slopes can be used for growing trees (silviculture) Rangeland for domestic animals can be located in areas where it is unsuitable for farming.

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17 Limiting Factors Agricultural limiting factor is the one factor that is available in the least supply in comparison to the need of the crop. Ex: Micro/macro nutrients, water

18 Cash vs. Subsistence Crops Crops grown to be eaten locally and/or right away are known as subsistence crops. Generally, these crops are sold locally, or eaten by the farmer himself. Crops may be traded or bartered, and do not move great distances or require special handling.

19 Cash crops are grown to be sold, and may be transported very long distances. Many cash crops could not be used for food. Ex: Tobacco, spices, tea, coffee, flowers Because they are transported long distances, cash crops require special conditions, such as refrigeration. The special handling of some crops accounts for their higher prices in markets worldwide.

20 Since cash crops provide hard currency to local and national governments, there is a financial incentive to grow them instead of subsistence crops which will provide food. This sometimes works against the provision of adequate food locally.

21 Approaches to Agriculture There are three major approaches to agricultural production: 1)Production based on mechanized technology -high demand for resources -little use for biological technologies fuel, water, inorganic fertilizers, land

22 2) Production based on biological technology -land conservation, water conservation, reduction in energy usage, reduced use Of fertilizer and pesticides 3) Organic food production -very low impact, organic vs. inorganic fertilizer, few if any pesticides. Studies have shown that many organic foods are HIGHER IN NUTRITION than non-organics.

23 Demand- vs. Resource-Based Agriculture Demand-based: production is determined by Economic forces, and limited by economics. Resource-based: limited by environmental sustainability and good use of resources. Production may exceed demand by a large margin, resulting in lower prices overall for the crop. Production is usually lower than demand, resulting in higher prices for the grower.

24 Maximum vs. Optimum Yield -Maximum is based solely on the crop yield, while optimum is based also on the ability of the agro-systems ability to sustainably produce without damage. Most modern agriculture is based on Maximum, not Optimum

25 Limits to Food Production Nutrients: chemical elements which are needed for plant growth and reproduction. Macronutrients: elements required in relatively large amounts by all living things. Ex: oxygen, nitrogen, potassium, carbon, sulfur calcium, magnesium The ‘Big Three” for plants: Nitrogen, Phosphorous and Potassium (N, P, and K)

26 2) Micronutrients: elements (typically metals) needed in small or trace amounts. Ex: zinc, copper, iron, chlorine These are often added as an additional supplement to the soil as indicated by soil tests. Liebig’s law of the Minimum: The growth and distribution of crops will be limited by the single factor that is in shortest supply or has the greatest impact.

27 Synergistic Effects: The change in availability of one nutrient affects the response of an organism to some other resource. Ex: Nitrogen on a lawn without water..low growth Now water the lawn….explosive growth, the grass can utilize much more water than before because of the nitrogen. At least until it runs out of water or nitrogen.

28 Water Availability The largest limit to food production “Dry Land” farming: using only rain -very dependent on the climate, which is changing globally. Irrigation: using water from other sources for crops. Constant supply, but sources are being over-utilized and drained.

29 - Irrigation improvements -drip, vs. flood irrigation -less lost to evaporation, more goes directly to the plant Chemigation: drip irrigation takes fertilizer/pesticide directly to plants, reduces need (loss to runoff)

30 Under- vs. Malnourishment The terms are not interchangeable! Undernourishment means that an individual does not receive enough calories each day to survive, and will eventually die of lack of energy. Malnourishment means that the individual lacks specific nutrients, such as proteins or vitamins. Ex: kwashiokor (protein), scurvy (vitamin C) Eye/vision degeneration (vitamin A)

31 Measures of Food Production 1) Supply on hand, measured in days How long would all of the food last if production stopped right now? 1995: 62 days 1996: 49 days This number will vary depending on world climate and production, as well as consumption rates. 2) Per Capita Food Production: the amount of food produced per person.

32 The Green Revolution The Green Revolution was a post-World War II idea that agriculture could be developed to produce great amounts of food. Needs: Lots of man-made inorganic fertilizers Lots of pesticides (post WWII was big for this) Intensive farming practices, including lots of irrigation and heavy tillage of the land. Improved varieties of plants that yield more food

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35 The Green Revolution focused on three main crops: Wheat Rice Corn Some success: Mexico, 1944: imports ½ of its wheat Mexico, 1956: Mexico is self-sufficient in wheat Mexico, 1964: Mexico exports ½ million tons of wheat

36 U.S.: Corn yields more than quadrupled from 20 bushels/ha (ha = hectare, which = 2.47 acres) to 100-250 bushels/ha Success in the developed countries as well! In developed corn-producing areas, yields increased by an average of 346%!

37 The end of the Green Revolution For all of its promise, the Green Revolution never did end worldwide hunger. Pests rapidly developed resistance to pesticides used over and over again. Many new crops had higher yields, but needed much more fertilizer and water. Any gains were quickly negated by large gains in population.

38 The Green Revolution relied heavily on fossil fuels, inorganic fertilizers, which are made from fossil fuels, and irrigation. In the same time that corn production rose by 346%, fossil fuel use for agriculture rose 810%. Ratio of Corn out : Energy in 1945: 3.5 1983: 2.5

39 Poor nations simply cannot afford the expense of high-input agriculture. -Fuel -Pesticides -Fertilizers (Mostly Nitrogen and Phosphorous) -Equipment and maintenance -Irrigation In addition, yield responses to increasing amounts of fertilizer have slowed. (Liebigs laws) 1 ton of N/ha = 20 bu increase, vs 1 ton of N/ha = 2 bu increase

40 Biotechnology, the next “Green Revolution” Biotech and gene engineering promises to end hunger and malnutrition by making crops more efficient in a number of ways: Increased yield/plant Plants that can grow in marginal conditions Plants that produce their own protective pesticides, reducing loss to pests Plants that produce more/different nutrients

41 Biotech has the possibility of being a problem as well… Introduced genes may cause allergies in crops that did not cause allergies previously. Patent fights over who has the right to grow the crops. (how can you patent a natural gene?) Increased costs to farmers (what about the poor subsistence farmers? ) Loss of genes to wild plants (= resistance to Conventional Pesticides)

42 A genetically modified crop which has a gene to cause the plant to become sterile after the first year. The Terminator Gene What implications does this have for subsistence farmers? This gene is intentionally introduced by the biotech seed companies to prevent the farmers from using seeds to re-plant year after year.


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