Chapter 13: Food, Soil Conservation, and Pest Management January 09, 2014
3 major food challenges of the world: 1) Poverty (land and money) 2) Providing and distributing food 3) Accomplishing food security in an environmentally sustainable manner (soil and water) Food Security http://www.theguardian.com/news/datablog/2012/jul/10/food-security-index
*Global food production has stayed ahead of population growth, but 1/6 people in developing countries cannot grow or buy the food they need. Root cause of hunger and malnutrition is poverty. can't afford to grow or buy food war and corruption can deny poor people access to food http://www.theguardian.com/news/datablog/2012/jul/10/food-security-index
Food Security: every person in a given area has daily access to enough nutritious food to have an active and healthy life National Level Government programs > help poor help themselves > family planning > education* *Women > jobs* > microloans > *India's National Food Security Bill
Food Security: every person in a given area has daily access to enough nutritious food to have an active and healthy life International Level developing countries do not produce enough food to feed their people, too poor to import food Developed nations and international lending institutions (World Bank) provide: > Technical advice > Funding
Food Security: every person in a given area has daily access to enough nutritious food to have an active and healthy life At all levels: Need to reduce harmful environmental effects of agriculture
Food Security: every person in a given area has daily access to enough nutritious food to have an active and healthy life What do people need to eat? Macronutrients: protein, carbohydrates, fats Micronutrients: vitamins and minerals Chronic undernutrition or hunger: not enough food to meet basic energy need Malnutrition: deficiencies of key nutrients Diet of poor consists mostly of grains (low-protein, high carbohydrate)
Famine: severe shortage of food in an area accompanied by mass starvation, deaths, economic chaos, and social disruption deplete seed grain stored for future crops eat breeding livestock mass migration Causes drought flooding war *Sudan civil war
Millennium Development Goal: Reduce # of hungry and malnourished people to 400 million by 2015 Statistics Today: Increased average daily food intake calories/person 1961-2000 Reduced # chronically undernourished or malnourished people from 918 million (1970) to 852 million (2005) 6 million children die/year due to under/malnutrition and increased susceptibility to disease 1/3 suffer from deficiency of vitamins/minerals US: 35 million people went hungry at times mostly due to poverty
What are the consequences of undernutrition and malnutrition? January 09, 2014
Iron Deficiency iron is a component of hemoglobin, which transports oxygen in RBC anemia > fatigue > increase susceptibility to infection > increases chance of dying from hemorrhage in childbirth Iodine Deficiency Iodine essential for thyroid gland: produces hormones to control body's metabolism. Stunted growth mental retardation goiter: swollen thyroid gland *Iodized salt
Possible solutions to reducing childhood deaths from hunger and malnutrition?
Possible solutions to reducing childhood deaths from hunger and malnutrition? Immunizations Encouraging breast-feeding Oral rehydration (sugar and salt in water to prevent dehydration from diarrhea) Vitamin A capsule Family planning (space births 2 years) Increasing education for women: nutrition, drinking water sterilization, contraception, childcare
Overnutrition: Food energy intake exceeds energy use *Suffer similar health problems as underfed people > lower life expectancy, more disease and illness, lower quality of life 60% American adults are overweight 33% American adults are obese 1 billion people face health problems from not eating enough 1.2 billion people face health problems from eating too much January 09, 2014
Food Production Asia, coastal areas 29% land area 11% land area Since 1960: Increase in global food production. *technological advances Challenges: > Environmental harm: pollution, irrigation, overgrazing, overfishing, etc.) > Loss of biodiversity* Destruction of natural ecosystems 14 plants and 9 animals provide 90% of world's food Wheat, corn, and rice provide more than half calories
Distribution of Types of Food Production January 09, 2014
Industrialized agriculture or high-input agriculture uses large amounts of fossil fuel energy, water, commercial fertilizers, and pesticides to produce monocultures and livestock animal for sale 1/4 cropland, produces 4/5 of world's food Greenhouses > *moving water plantation agriculture: growing cash crops on large monoculture plantations, mostly for sale in developed countries feedlots: Densely populated animal factories, fed grain > *waste, water, energy
US Agribusiness giant, multinational corporations control growing, processing, distribution, and sale of food 18% GDP Efficiency > Increase in yield/hectare prevent forests, grasslands, wetlands from being converted to farm > Reduced input of labor and resources (except pesticide) Food is cheaper > Taxes to subsidize food producers and distributors Availability of cheap energy (oil) to use machines, process food, produce fertilizers and pesticides January 09, 2014
http://en.wikipedia.org/wiki/file:florida_chicken_house.jpg January 09, 2014
http://www.globalagriculture.org/report-topics/industrial-agriculture-and-small-scale-farming.html January 09, 2014
*Agriculture is world's largest industry and most environmentally harmful January 09, 2014
Traditional agriculture Low input polyculture Traditional subsistence agriculture: uses mostly human labor and animals to produce only enough crops/livestock for farm family's survival Traditional intensive agriculture: use more human and animal labor, fertilizer, and water to get higher yield. Produce enough food to feed family and sell
Traditional agriculture Interplanting: Grow several crops on same plot simultaneously > biodiversity = sustainable. Won't lose crops to pests, weather, etc. > 4 types 1. polyvarietal cultivaton: planting plot with several genetic varieties of the same crop 2. intercropping: two or more different crops are grown at the same time on a plot (wheat and legume) 3. agroforestry/alley cropping: crops and trees grown together 4. polyculture: many different plants are planted together «mature at different times, keep soil covered, less need for fertilizer, pesticides, herbicides http://permaculturenews.org/2013/05/22/next-generation-polycultures/
January 09, 2014 Corn and Soy Hedges, Kathryn. mvc-308s.jpg. 1999. Pics4Learning. 8 Jan 2014 <http://pics.tech4learning.com> How often do you eat corn and soy? http://en.wikipedia.org/wiki/file:soybean.usda.jpg
Corn and Soy The US is the world's largest producer of corn (32%) and soybean (more than 50%) 84 million acres ~ size of Germany
Corn and Soy The US is the world's largest producer of corn (32%) and soybean (more than 50%) Distribution of corn use: > 40% ethanol (growing demand) > 37% feed livestock > 11% food *mostly as HFCS > 8% exported > rest for other industrial uses Large amounts of resource (fertilizer, water, etc.) are used, with environmental tolls Large demand for corn for ethanol is reducing diversity of American farms. Costs taxpayers: $90 billion between 1995-2010 88% of corn and 93% of soybeans grown in the US is genetically modified
Brainstorm 5 negative impacts of conventional agriculture with your elbow buddy. Be ready to share. January 09, 2014
Part II: Where does your food come from? January 09, 2014
According to the EPA, the average gasoline vehicle in the US has a fuel economy of about 21 miles/gallon. every gallon of gasoline creates about 8887 grams of CO2 every mile driven creates about 423 grams of CO2 http://www.foodemissions.com/foodemissions/calculator.aspx We have only looked at the distance that food has traveled to get to our table, but what other impacts can food have, espeically the way it is grown, distributed, and eaten today?
Soil Erosion: movement of soil components (esp. surface litter and topsoil) > wind and water > roots of plants anchor topsoil, prevent erosion > human activities increase soil erosion > Lose soil fertility + water pollution topsoil = renewal resource (slow!)
Types of erosion: sheet erosion rill erosion gully erosion *Using a renewable resource unsustainably
Desertification: productive potential of drylands falls by 10% or more because 1. natural climate change 2. human activities that reduce or degrade topsoil *Classified as moderate to very severe depending on drop in productivity
Desertification affects people's livelihood: loss of soil productivity = unable to grow food displaces people (Dust Bowl, Midwestern US) January 09, 2014
Repeated irrigation can lead to salinization and waterlogging. January 09, 2014
Soil conservation: ways to reduce soil erosion + restore soil fertility *Keep soil covered in vegetation! Why? 1. Conservation-tillage farming: Modern machinery can plant crops w/o disturbing the soil Increases crop yields raises soil carbon content lowers use of water, pesticide, tractor fuel
January 09, 2014 Other methods of reducing soil erosion: *Reduce runoff and erosion 1. Terracing 2. Contour farming 3. Strip Cropping http://en.wikipedia.org/wiki/file:terraced_fields_sa_pa_vietnam.jpg Planting on steep slopes! Planting on slopes!
January 09, 2014 Other methods of reducing soil erosion: 4. cover crops 5. alley cropping 6. windbreaks or shelterbelts http://commons.wikimedia.org/wiki/file:2004_0609_italian_ryegrass_cover_crop.jpg
Fertilizer: replace nutrients that have been removed from soil from repeated crops or washed, blown, leached out of soil. Organic fertilizer Animal manure green manure compost Commercial inorganic fertilizer N, P, K *doesn't replace organic matter Other alternative: crop rotation
http://www.amusingplanet.com/2010/07/hungry-planet-what-world-eats-by-peter.html