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Agriculture and Global Food Security

Agriculture and Global Food Security. APES notes. In the beginning…. All humans got their food by hunting, gathering and fishing Then humans invented agriculture, changing natural ecosystems into ones devoted to the production of food, fiber and fuel

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Agriculture and Global Food Security

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  1. Agriculture and Global Food Security APES notes

  2. In the beginning… • All humans got their food by hunting, gathering and fishing • Then humans invented agriculture, changing natural ecosystems into ones devoted to the production of food, fiber and fuel • A population explosion followed; agriculture gave us food security but was also one of the most environmentally damaging human activities • And now even our food security is at risk

  3. The DEMAND for agriculture is increasing due to: • Increasingpopulation (about 9 Billion people by 2050, all needing food • Increasing need for food for livestock as affluent humans demand more meat protein • Increasing demand for biofuels (food crops that can be converted to ethanol, biodiesel and methane)

  4. But the SUPPLY OF FOOD IS THREATENED BY 3 THINGS: • Increasing temperatures due to climate change • Decreasing water supply due to overpumping of aquifers • Increasing soil erosion due to overplowing and poor farming techniques • Some MEDC, such as South Korea and China have taken the unusual step of buying or leasing arable land in other countries to grow their own food. These have been called LAND GRABS and occur in very poor countries, mostly in Africa, where unscrupulous leaders lease land to foreigners for as little as $1 per acre per year. That the governments of poor countries are willing to sell land to foreign interests while their own people are hungry is a sad commentary on their leadership!

  5. More on the LAND GRABS • WHO BENEFITS? The foreign investor since they supply the equipment, the fertilizer, the pesticides, the seeds and then ship the food back to their own country. At best locals will work as farm hands but most farming is mechanized so jobs will be few. Host countries might get more roads and ports (infrastructure) however • WHO LOSES? The host country village farmers since they are removed from the land, plunging them into food insecurity but also increased water scarcity and soil erosion after the foreign countries farm the land then take the food

  6. HOW DO WE INCREASE CROP YIELDS TO MEET THE INCREASED DEMANDS? • BEFORE 1950 greater demand for food was met by taking more land into cultivation and improving farming technology. Today, there is little likelihood of more arable land becoming available or a rapid increase in technology. Yet we still have to double crop production to keep ahead of current demand

  7. There is no more arable land • ANY INCREASE IN THE AMOUNT OF ARABLE LAND TODAY involve habitat destruction: DEFORESTATION, OR draining wetlands Adding farming land by deforestation would a)lower biodiversity B) increase Green House Gases (GHG), contributing to climate change, C) reduce ecosystem services such as flood control, food and shelter for young animals…

  8. Practice questions • At the current rate of growth, Earth’s human population will double in about 50 years. Which of the following is the LEAST viable strategy for ensuring adequate nutrition for a population of this size? • Increasing the number of new food crops from the great diversity of plant species • Doubling the area of arable land on a global basis • Developing systems for making the global distribution of food more equitable

  9. In reality, we are LOSING arable LAND to desertification, salination, erosion and urbanization But agriculture is essential Without agriculture there would not be enough food to keep up with demand Agriculture is also important economically (a country’s GDP) and for personal livelihoods of family farmers

  10. Practice 3 types of elaboration in your writing… • Agriculture (CAUSE) lowers biodiversity (EFFECT) therefore (CONSEQUENCE)… • Agriculture (CAUSE) increases the amount of greenhouse gasses in the air (EFFECT) because (EXPLANATION)… • Agriculture (CAUSE) reduces the ecosystem services of forests (EFFECT) such as (SUPPORTING DETAIL)

  11. Today we depend on just 3 crops … • WHEAT • RICE • CORN Are the top crops for supplying calories and nutrients globally, as people increasingly eat the same types of food. Diets are far less nutritionally diverse. In recent years, the use of grain, such as corn as an energy source (biofuel) has increased food prices and contributes to world hunger and land grabs

  12. About 1 billion people worldwide lack access to adequate QUANTITY of food • Undernourishment means not consuming enough calories to be healthy. An average person needs approx. 2000 kcal/day for proper growth, learning abilities, physical work and to cope with infections • Most undernourished people are ruralpoor, living on less than $1.25/day, so even a small increase in food prices drive millions more into hunger

  13. Health impact of undernourishment • Marasmusis a form of severe emaciation leading to loss of energy and large numbers of deaths. • Undernourishment reduces the capacity to fight disease- Diarrhea, measles, malaria and respiratory diseases are common in the developing world. Well fed people can fight them off.

  14. Starvation • Lack of food calories causing exhaustion of the body. • When starvation occurs on an epidemic scale, accompanied by increasing mortality, we call it a FAMINE

  15. Practice question • Deficiencies in protein and other key nutrients is known as: • A) undernutrition • B) malnutrition • C) hunger • D) calorie overdraft • E) starvation

  16. Health impact of Lack of sufficient QUALITY of food • Malnourishment is the lack of sufficient protein or vitamins or other nutrient regardless of the number of calories they consume • Malnourished people may get enough calories (quantity), but poor quality food

  17. Health impact of Malnutrition (examples) • Kwashiokor is the result of inadequate protein and vitamins in the diet • Anemia (iron deficiency) is the most widespread nutritional deficiency in the world. Anemic women are more likely to die in childbirth

  18. More Malnutrition impacts • Vitamin A deficiency: • can cause blindness, especially in children • Reduces ability of immune system to cope with infections • Zinc and Iodine deficiency: • Decreased immunity to disease • Iodine deficiency is the single greatest cause of preventable mental retardation and learning disability • Stunted growth

  19. As global incomes increase, more people demand better quality food • There is a strong correlation between income (GDP) and the consumption of meat and diary protein • Growing meat is environmentally damaging

  20. The importance of animal source food • Meat and diary proteins are more digestible than plant sources. • Animals also provide many key micronutrients such as zinc, iron and vitamin B-12 In a nutrition intervention study of Kenyan children the addition of meat increased the lean body mass (growth) by 80% and improved cognitive development (on-the-spot reasoning and problem solving abilities) over 2 years

  21. THE FOOD WE NEED • A food calorie or kilocalorie (kcal) is the amount of energy needed to raise the temperature of 1kg of water by 1°C and is acquired through digestion and oxidation (respiration). • Carbohydrates are the main source of energy, yielding about 2kcal/g • Fats are a secondary energy source, yielding about 9kcal/g. Fats are essential to growth in early life and are essential to absorbing some vitamins, such as vitamin A, but can lead to heart disease and increased cholesterol • Proteinsare necessary for muscle and bone growth

  22. 2. Even with enough calories, chronic malnutrition can lead to: I. compromised mental development II. Increased susceptibility to nonfatal infectious disease III. Stunted growth a) I only b) II only c) I, II and III Practice questions

  23. Diseases from overnutrition • Obesity: is the result of ingestion of too many calories and improper foods causing individuals to be more than 20% above their ideal weight. • Obesity can lead to type 2 diabetes, heart disease and stroke • Excess meat in the diet can lead to cancer or high cholesterol which may in turn lead to a heart attack

  24. LESS ACCESS OF FOOD: • Poverty- Much of the world exists on less than $1.25 per day (economic access) • Political factors such as civil unrest, poor infrastructure or natural disasters that interrupt distribution (and/or production) • Diversion of resources to feed livestock rather than people (physical access) • Diversion of food crops for use as biofuel (physical access) • Climate change: every 1°C rise in temperature = 10% loss of grain

  25. Living on $1/day • Americans in Haiti • http://youtu.be/VGeFpz10baw • NOTE- about 52% of all people living in the HAITI are undernourished (source-NatGeo, 2014) the highest rate in the world. Haitians have endured an earthquake (2010), a hurricane (2012) and a drought (2014), all impacting food security

  26. Practice question • The factor that indicates the GREATEST cause of malnutrition and hunger is: • A) poverty • B) age • C) location • D) gender • E) blood pressure

  27. GOVERNANCE-Federal Domestic Food Assistance Programs: short term solutions • The Food and Nutrition Service administers all of its programs in partnership with the states. • 94% of all federal expenditures for food assistance went to five programs: • Food Stamp Program (EBT) • National School Lunch Program • Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) • Child and Adult Care Food Program • School Breakfast Program

  28. International food aid: short term solution • Within the UN, specialized agencies from the WHO to the FAO foster international cooperation. • The FAO (food and agriculture organization) collects and analyzes global agricultural data and provides technical assistance • Food assistance is done by the World Food Programme

  29. Long term solutions for sustainability in food for people • produce higher crop yields that are drought tolerant, disease resistant and conserve fertile soils. • Diversify food production to include local , indigenous vegetables to feed families if the imported crop is threatened by disease, flood or drought • Lower food waste to get surplus food to people who need it • stabilize the world population and shift to smaller family size

  30. THE GREEN REVOLUTION-the first attempt at food security • Started in 1960s as a way to end famine by increasing crop yield per hectare (1ha= 2.5 acres) in Asia and Latin America • The USAID distributed packets of- • High yielding crop varieties of corn, rice and wheat • Inorganic fertilizer required to maximize growth • Improved irrigation technologies • Pesticides and herbicides to reduce competition and insect pests

  31. Breeding high yielding crops • By selectively cross breeding varieties, new strains of grains were developed. Seeds from all over the world were crossed to produce grain that could grow in all microclimates and at all times of the year • This genetic modification was easier once specific genes were recognized in plants

  32. Effectiveness of 1st green revolution • Allowed Asia and Latin America to become self sufficient in grain production- more income (GDP) with no further need to import grain • Farmers doubled their yields and incomes. In Vietnam, rice became known as Honda Rice since profits paid for motorcycles.

  33. Impacts of 1st Green Revolution • Major environmental consequences: • Increased inorganic fertilizer use which are manufactured using fossil fuels and themselves emit potent GHG when they are applied to fields. Excess fertilizer can also cause cultural eutrophication • Major environmental consequences: • Increased water use depleted natural river flow altering habitats; contributed to soil salinization; loss of habitats such as wetlands; changing the flow of rivers by damming or channelizing rivers so affecting the transport of sediments downstream…

  34. Impacts of 1st green revolution • An increased pesticide use which can cause a loss of beneficial insect species; secondary pest infestations as natural predators of insects are killed; rise in pesticide resistant pests; release of HAAs, like Atrazine, into aquatic ecosystems • Fertilizers and pesticides are very expensive for poor farmers and farmers with very small farms so many small farmers did not benefit from this first revolution

  35. PESTICIDES increase yield/ha Pesticides are valuable for preventing crop loss due to herbivory by insect, rodent or viral pests and competition with weeds They include insecticides (for bugs), herbicides (weeds) and fungicides (mold, spores) and rodenticides (mice) Although initially effective, pesticide use ultimately fails and necessitates increased dosage over time (the pesticide treadmill)

  36. 1. They save human livespreventing premature deaths from insect transmitted diseases such as malaria, yellow fever, zika, west nile and dengue. 2. They increase crop yields, work fast and can be stored, controlling most pests quickly, with a long shelf life, and are easily shipped and applied. With less arable land, increasing crop yield is essential! Pesticides have some advantages and will probably always be used to some extent

  37. Disadvantages of insecticides • Cause nerve damage in farm workers and birds, leading to spasms and death when the spray is inhaled • Some, like DDT, are persistent, lasting for many years after spraying • Pesticides can bioaccumulate and biomagnify in tissues of animals, increasing in concentration up the food chain. Pesticides are suspected carcinogens and hormone/endocrine disruptors • Some pesticides have been implicated in egg shell thinning, lowering the population of some birds and alligators

  38. Disadvantages of herbicides • Herbicides, such as Atrazine, used to kill weeds also have negative impacts: • Cause male de-masculinization of frogs and fish • May be responsible for the drastic reduction in frog populations worldwide

  39. The effect of herbicides on the environment • Some herbicides such as atrazine are linked to endocrine cancers in humans and frogs • They are also HAA (hormonally active agents) that cause the feminization of fish by turning on a gene that changes testosterone into estrogen • Atrazine is used as a weed killer in agriculture. About 1.2 million pounds per year is carried by runoff and river flow into the Gulf of Mexico. Atrazine can also attach to dust particles.

  40. Early pesticides • Salt, sulfur and arsenic are naturally occurring in rocks and were the first generation pesticides used in agriculture • They were deadly but effective because they were applied on a much smaller scale

  41. Post WWII pesticides • Organochlorines (aka chlorinated hydrocarbons) and organophosphates are second generation pesticides used on large scale agriculture and household pests • DDT, aldrin, dieldrin and heptachlor are some examples. They were applied indiscriminately

  42. PESTICIDES also impact human health • Organochlorines such as DDT, exposure causes headaches, dizziness, vomiting and abdominal pain. They interfere with the production of ATP when the spray is inhaled

  43. Harmful DIRECT Effect of pesticides on human health • Organophosphates cause damage to the nervous system and convulsions. They block acetylcholinesterase enzymes from deactivating nerve impulse transmission. Farm workers spasm uncontrollably and can die from inhaling the spray

  44. Rachel Carson and her book Silent Spring • https://youtu.be/SeJNRaE11A0 • Looked at the significance of pesticide use on the environment and human health beyond the mere killing of insect pests

  45. Pesticides are mobile • Pesticides can also be carried by migrating birds and animals and by ocean currents • Pesticides used in tropical regions can make their way to the arctic through the atmosphere (called the grasshopper effect) Pesticides end up in the soil, over time they evaporate and are carried by wind to the north. When temperatures drop the pesticides condense and fall to earth. This process only takes a few days! The arctic is becoming a chemical sink

  46. Disrupting food chains on the farm • Using a pesticide to eliminate a pest can have unintended consequences such as, a drop in the population of birds or other predators of the target insect or an increase in the numbers of secondary pests • Secondary pests develop when the prey of the target insect grow to huge numbers without their predator. Secondary pests may also develop when competitors of the target insect suddenly find themselves without competition for the crops

  47. Insects eventually become resistant to chemical pesticides • In the 1970s organochlorines were replaced with less toxic, less persistent pesticides. • But insects develop resistance to pesticides, so they eventually become ineffective. • Today, hundreds of species of insects and weeds are resistant to pesticides and herbicides, encouraging farmers to put more and more pesticides into the environment. This is known as a pesticide treadmill

  48. Farms should be placed farther away from surface water bodies to limit the amount of agricultural runoff and drift from aerial spraying that enters streams. Many pesticides dissipate rapidly in soil as microbes utilize the pesticide as a source of carbon. A natural riparian zone between farmland and stream could act as buffer. Bacteria in the soil can break down some pesticides before they enter waterways. 3. Reduce the amount of pesticide used, turning to IPM instead which use mechanical and biological alternatives 4. Promote organic farming which, by definition, does not use pesticides 5. Require training and licensing in the proper use of pesticides Ways to Mitigate pesticide pollution

  49. AGROECOSYSTEMS • Sustainable agriculture relies on resources internal to the ecosystem to increase yield- using different species that benefit each other. For example, trees and shrubs provide shade for herbs, legumes provide nitrogen and livestock can furnish manure. Mixtures of crops can also deter pests. The more diverse the farm, the more resilient and sustainable. Sustainable farms do not require as much input into the system

  50. WHAT IS AN ECOSYSTEM? An ecosystem is a community of organisms and its nonliving environment in which chemical elements cycle and energy flows. Ecosystems can be natural or artificial.Natural ecosystems carry out public service functions for us and are considered natural capital in an economic and social sense. Treating a farm as an ecosystem will use some of these services to maximize crop yield

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