Chapter 11- Feeding the World. Global Undernutrition. Undernutrition 1/21/2015. January 21, 2015 Mr. Alvarez

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1 Chapter 11- Feeding the World January 21, 2015 Mr. Alvarez Global Undernutrition Undernutrition Undernutrition- not consuming enough calories to be healthy Average human needs approximately 2,200 kilocalories/day Long term deficit of Kilocalories/day can lead to diseases Can lead to improper brain development and lower IQ amongst children 1

2 Marasmus Malnourishment Malnourishment- regardless of the number of calories a person consumes, their diets lack the correct balance of proteins, carbohydrates, vitamins and minerals Food Security- the condition in which people have access to safe, and nutritious food that meets their dietary needs for an active and healthy life Food Insecurity- the condition in which people do hot have adequate access to food Famine Famine- a condition in which food insecurity is so extreme that large numbers of deaths occur in a given area over a relatively short period More than 5 deaths per day per 10,000 people due to lack of food Annual mortality rate of 18% during a famine Could be the result of crop failures, drought, or social and political causes 2

3 Overnutrition Overnutrition- the ingestion of too many calories and improper foods which causes a person to become overweight 1 billion people in the world who are overweight 300 million of these people are obese (more than 20% higher than their ideal weight) At risk diseases: Type 2 diabetes Hypertension Heart disease Stroke 3

4 What we eat There are 50,000 edible plants worldwide, but 60% consists of either Corn, Rice and Wheat Globally, 300 kg of grain per person per year is consumed Meat = 40 kg per person per year Meat- livestock (beef, veal, pork and lamb) and poultry (chicken, turkey and duck) Meat consumption proportional to economic growth Fish = 21 kg per person per year Revis Family: United States Mexico 4

5 Annual Meat Consumption Mali Kuwait 5

6 Japan India Reasons for Malnutrition 1. Poverty- lack of resources that allow one access to food Unequal food distribution- food exists, but not everyone has access (affordability) 2. Political and Economical Factors Refugees from war or natural disasters 2008 food prices led to riots in Haiti, Egypt, Ivory Coast, Cameron, Yemen 3. Agricultural Resources used to feed livestock/poultry 40% of grain grown in the world to feed livestock In U.S., corn and soybeans grown primarily as animal feed 10% of calories in grain or soybeans fed to cattle are converted to beef calories 6

7 Global Grain Production The Green Revolution Industrial agriculture (agribusiness)- applies the techniques of the Industrial Revolutionmechanization and standardization-to the production of food Energy subsidy- energy input per calorie of food produced 20 kg of grain to feed cattle to produce 1 kg of beef = energy subsidy of kg of grain to feed chickens to produce 1 kg of chicken = energy subsidy of 2.8 Energy Subsidies Average U.S. diet has an energy subsidy of 10, most of which come from fossil fuels Produce fertilizer and pesticide Operate tractors Pump water for irrigation Harvest food Prepare food for transport Average food item travels 1,240 miles from farm to plate 17% of total commercial energy goes into growing, processing, transporting and cooking food 7

8 The Green Revolution cont. Green Revolution- new management techniques and mechanization as well as the triad of fertilization, irrigation and improved crop varieties American scientist Norman Borlaug ( ) won Nobel Peace Prize for developing higheryield, disease resistant wheat Results of Green Revolution Mechanization- using machines to replace the work of humans Developed nations have 5% of workforce in agriculture Developing nations have 40-75% of workforce in agriculture Cost of Combine Harvester (separates out grain and seed for transport) costs $150,000-$400,000. Only Large Farms can afford this expense From , average farm in Iowa Doubled Also leads to single-crop farms Irrigation 16% of world s agricultural land is irritated Produces 40% of world s food Can lead to groundwater depletion and drawn down aquifers (cone of depression) Can promote saltwater intrusion in coastal areas Waterlogging- occurs when soil remains under water for prolonged periods, impairs root growth because roots cannot get oxygen Salinization- occurs when the small amounts of salts in irrigation water become highly concentrated on the soil surface through evaporation 8

9 Fertilizers Agriculture removes organic matter and nutrients from soil Fertilizers contain primarily nitrogen, phosphorus and potassium Organic Fertilizer- composed of organic matter from plants and animals Typically made up of decomposed animal manure Synthetic (Inorganic)- produced commercially by combusting natural gas, which allows Nitrogen from the atmosphere to be fixed and captured in fertilizer Highly concentrated and cheaper Carried off by runoff into adjacent waterways. Leads to Algal Bloom Death Decomposition Hypoxia Arguable that we could not feed the world without Inorganic Fertilizers 9

10 Synthetic Fertilizer Production; Overapplication/runoff (eutrophication) Monocropping Monocropping- An agricultural method that utilizes large plantings of a single species or variety Dominant agricultural practice in United States Wheat and Cotton frequently grown in monocrops of 405 hectares or more Large expanses of land to be planted and then harvested at same time Large machinery can harvest easily Fertilizer and pesticide can be specialized to that crop 10

11 Negative Effects of Monocropping 1. Soil degradation because whole fields are readied and harvested at the same time o Bare soil can be susceptible to wind erosion o Certain farmland in U.S. loses an average of 1 metric ton of topsoil per hectare 2. Makes crops more vulnerable to attack by pests and bacteria/fungi Can lead to exponential growth Predators of pests live on non-crop plants Leads to increased usage of pesticides Pesticides Pesticides- substances, either natural or synthetic, that kill or control organisms that people consider pets Broad Spectrum- kill many different types of pests Selective- focus on a narrower range of organisms In U.S. over 227 million kg (1/3 of worldwide usage) of pesticides are applied to food crops, cotton and fruit trees Insecticides- target species of insects and other invertebrates that consume crops Herbicides- target plant species that compete with crops (weeds) Negative Effects of Pesticides 1. Pesticides kill or injure organisms other than intended targets 2. Can be Persistent- they remain in the environment for a long time Bioaccumulation- pesticide builds up over time in the fatty tissues of predators DDT was banned for this reason in 1972 Made shells of Bald Eagles weak. Lead to Endangerement 11

12 Pesticide persistence; pesticide treadmill; collateral damage Bees dying from use of neonicotinoids Negative Effects of Pesticides cont. 3. Can be nonpersistent- pesticides break down relatively rapidly (weeks to months) Fewer long-term effects but must be applied more often. Environmental effect not always lower 4. Pest population may evolve resistance to pesticides over time Pesticide treadmill- the cycle of pesticide development, followed by pest resistance, followed by new pesticide development, etc. 5. Can kill organisms that benefit farmers, such as insects that prey on pests or fix nitrogen 6. Can runoff into surrounding surface waters and enter groundwater 12

13 Benefits of Genetically Modified Organisms Increased Crop Yield and Quality Create strains of organisms resistant to pests and harsh environmental conditions (drought, salinity) Scientists can insert genes for plants to produce essential nutrients for humans (yellow rice) Organisms modified to produce pharmaceuticals Organisms modified to grow larger/faster Potential Changes in Pesticide Use Resistance to pests could reduce pesticide usage Bacillus thuringiensis produces toxin that kills corn pests, Bt gene inserted into genetic material of corn plants Roundup Ready gene allows farmers to spray herbicide without harming crop plants Increased Profits Less Pesticide usage Greater Yields Higher incomes for farmers/lower food prices for consumers Concerns about GMO Safety for Human Consumption Ingestion of GMO s may be harmful to humans, although currently little evidence Genes transported between foods can trigger allergies Effects on Biodiversity Newly added genes will spread to wild plants which will alter/eliminate natural genes Attempts have been made to introduce buffer zones Unable to know what genes will be lost Regulation of GMO s Currently no U.S. Regulations Possible future mandate of GMO Labeling Might suggest to consumers that there is something wrong with GMO s Difficult because small traces of GMO materials found throughout U.S. Crops People that want to avoid GMO s can but organic food 13

14 Shifting Agriculture Shifting Agriculture- clearing land and using it for only a few years until the soil is depleted of nutrients Slash-and-Burn- existing tres and vegetation are cut down, placed in piles and burned Resulting ash rich in potassium, calcium, and magnesium (makes soil fertile) Nutrients depleted after a few years If deforestation is in area of heavy rainfall, nutrients washed away, along with soil Why Slash-and-Burn is bad If plot of land is overused the land may never fully recover Then only suitable for animal grazing Burning process oxidizes carbon (converts Carbon to Carbon Monoxide and Carbon Dioxide) Higher concentration of Atmospheric CO 2 14

15 Desertification Desertification- The transformation of arable, productive land to desert or unproductive land due to climate change or destructive land use Nomadic Grazing Nomadic Grazing- moving herds of animals, often over long distances, to find seasonally productive feeding grounds May be only sustainable way to use soil types with low productivity 15

16 Sustainable Agriculture Sustainable agriculture- fulfills the need for food and fiber while enhancing the quality of the soil, minimizing the use of nonrenewable resources and allowing economic viability for the farmer Ability to continue agriculture on a given piece of land indefinitely More expensive where labor costs are high Intercropping Intercropping- Two or more crop species planted in the same field at the same time to promote a synergistic interaction between them Corn requires much Nitrogen, planted with peas, Nitrogenfixing crop Crop rotationrotating the crop species in a field from season to season Agroforestry Agroforestry-Intercropping trees with vegetables Differing heights act as windbreaks and catch soil that might otherwise be blown away (reduces erosion Trees protect vegetable crops, soil and provide fruit and firewood 16

17 Contour Plowing Contour Plowingplowing and harvesting parallel to the topographic contours of the land Helps prevent erosion by water while still allowing for practical advantages of plowing Plowing and Tilling-Unsustainable Plowing and tilling are processes that physically turn the soil upside down and push crop residues under the topsoil, thereby killing weeds and insect pupae Soil particles now disturbed, broken apart and susceptible to erosion Increases the exposure of organic matter deep in the soil to oxygen Leads to oxidation of organic matter Reduction in the organic matter content of soil Increase in atmospheric Carbon Dioxide concentrations No-till Agriculture No-till agriculture- helps to stop soil degradation by leaving crop residues in the fields and not tilling the land after each harvest. o Intact roots hold soil in place which reduces erosion o Reduces CO2 emissions o Downside: Farmers must apply more herbicides 17

18 Integrated Pest Management Integrated Pest Management (IPM)- uses a variety of techniques designed to minimize pesticide inputs Crop rotation and intercropping Use of pest-resistant crop varieties Creating Habitats for predators of pests Agroforestry encourages presence of insect-eating birds Many herbs and flowers attract beneficial insects Limited use of pesticides Through careful observation, catch pest infestations in early stages and treat using natural controls or small dosage of pesticides Saves money as well Downside: Farmers must be trained in IPM Wasp laying eggs in paralyzed caterpillar Organic Agriculture Organic Agriculture- the production of crops without the use of synthetic pesticides or fertilizers Follows basic principles: Use ecological principles and work with natural systems rather than dominating them Keep as much organic matter and as many nutrients in the soil and on the farm as possible Avoid the use of synthetic fertilizers and pesticides Maintain the soil by increasing soil mass, biological activity, and beneficial chemical properties Reduce the adverse environmental impacts of agriculture 18

19 Drawbacks of Organic Agriculture Labor costs are significantly higher Farmers can sell harvest at higher price to consumers who prefer organic foods Farmers less likely to use no-till methods because they don t use herbicides May treat soil with a propane flamer before planting to get rid of weeds (uses fossil fuels) 19

20 High-Density Animal Farming Concentrated Animal Feeding Operations (CAFOs)- large indoor or outdoor structures designed for maximum output. Used for beef cattle, dairy cows, hogs, poultry Confined or allowed very little room for movement during all or part of their life cycle May contain as many as 2,500 hogs or 55,000 turkeys in a single building Farmers minimize land costs Improve feeding efficiency Increase the fraction of food energy that goes into the production of animal body mass CAFO Animals Fed Antibiotics Antibiotics and nutrient supplements fed to animals to reduce the risk of adverse health effects and diseases, which would normally be high in such a highly concentrated population Contributing to the increase in antibiotic-resistant strains of micro-organisms that affect humans An average CAFO produces over 2,000 tons of manure annually (as much as a 5,000 person town) Manure runoff can cause eutrophication Manure can contaminate nearby waterways 20

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22 Free-Range Chicken and Beef Free-range meat- chicken or cow that has wandered free for the duration of its life cycle Spread out=less likely to spread disease Reduce or eliminate the use of antibiotics Animals graze or feed on natural productivity of land Less fossil fuel goes into the raising of free-range meat Manure and urine dispersed over the range area and naturally processed by detritivores and decomposers Drawback: Uses more land than CAFOs Cost of meat is significantly higher 22