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World population expected to rise to 10 billion. Demand for food and water will rise. Next topics covered in class are about food and water. Concern that population growth would continue after food production levels off. Food Production. Amount. Population Growth. Time.
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World population expected to rise to 10 billion Demand for food and water will rise Next topics covered in class are about food and water
Concern that population growth would continue after food production levels off Food Production Amount Population Growth Time
Changes brought about by modern agriculture and the Green Revolution • Temporarily closed the gap between food production and need in some countries– food production has increased (& fertility starting to come down) • Heavy reliance on irrigation and fertilizers • Negative impact on small farmers and culturally specific crops
Fig. 9-3. Yield of several major crops increased greatly with modern agriculture techniques
Subsistence Farming • Labor intensive • Use of marginal lands • Clearing of tropical rain forests • Can cause environmental degradation
Industrial Agriculture mechanization: fossil fuels new lands: best land already in production (~25% in US, ~38% world wide) little new land available in US, land still cleared in developing countries agro-chemicals: fertilizers & pesticides increased irrigation: conflicting water uses, irrigated land produces ~40% of worlds food selected cultivars: loss of diversity
Global Population and Grain and Meat Consumption Fig. 9-9 here
How have we increased world food production? • Traditional agriculture • small farms • animal labor • low use of chemicals and irrigation • natural plant varieties • Industrialized agriculture • large farms • fossil-fuel driven machinery • intense use of pesticides, fertilizer and irrigation • high-yield plant varieties
Green Revolution Father of green revolution (Norman Borlaug) won Nobel Peace Prize in 1970 Very positive effect on world hunger Many high yield crops require high water and fertilizer Favors non-traditional cultivation methods Many traditional African crops not affected
Bio tech crops & Genetically Modified Organisms Insert genetic material (DNA) from one organism into another to provide a desired trait
Examples of desired traits Insect resistance Herbicide resistance Drought/heat/salt tollerance Improved nutritional value Vaccine delivery
Problems Spread of genes to non-crops: super weeds, harm wild species Food safety: ex, allergies, big concern in Europe Access to technology: yearly seed purchase & dependence on foreign technology in developing countries
Burden of proof Should regulators need to prove that food is not safe? Should companies have to prove that food is safe?
[per capita gross national product – 1999-2000] High income countries: Too much meat, salt, fat. Not enough fiber. Food processing may reduce mineral and vitamin content. Low income countries: Lack of proteins and vitamins (malnutrition) and lack of calories (undernutrition)
Why do the fries taste so good? Read excerpt from Fast Food Nation. Potato farming is example of trends towards industrial farming The story of one potato baron- and lots of other potato farmers For each $1.5 spent on fries in restaurant, $0.02 goes to farmers Fast food companies purchase potatoes for $0.03 per pound and sell fries at $6.00 per pound
Why do the fries taste so good? “natural and artificial flavoring” is made in NJ 1950’s processed food sales increased dramatically 10,000 processed foods introduced every year in US “flavorists” (chemists) create compounds that give processed foods taste
U.N. World Health Organization: Undernourished: People who receive less than 90% of their minimum dietary intake on a longterm basis. Seriously undernourished: People who receive less than 80% of their minimum dietary intake on a longterm basis. Overnourished: People who take in excess calories on a routine basis over the longterm. Malnourished: A nutritional imbalance caused by the lack of specific dietary components or an inability to absorb or utilize essential nutrients.
U.S. Department of Agriculture Food Guide Pyramid; http://www.mypyramid.gov/index.html North Americans consume on average about 35% of their daily calories as fat.
Distinguishes between healthy and unhealthy types of fat and carbohydrates. • Fruits, vegetables, healthy fats and whole grain foods are encouraged. • Consumption of refined carbohydrates, butter and red meat should be limited. Source: Scientific American 2002
Essential dietary requirements • Complex carbohydrates • Usually 80% of daily caloric intake • Proteins • About 40 grams/day needed. Essential aminoacids • Enzymes, cell structures, nervous tissue • Lipids (fats, oils, etc.) • Energy storage; cellular membranes • Minerals (ex. calcium, iodine, iron, etc.) • Component of cellular structures; regulation of cellular reactions • Vitamins • Organic molecules we cannot synthesize and have to get from our diet.
Major Crops • Wheat, rice, maize • 60 % of the calories and 56 % of the protein that humans consume directly from plants. • staple of most of the 4 billion people in developing countries • Potatoes, barley, oats, rye • grow well in cool, humid climates • staple of mountainous and higher latitude regions • Cassava, sweet potatoes and other root crops • grow well in warm wet climates (South America, Africa, South Pacific region) • Meat/milk • Uneven distribution • Fish • Important source of protein
Causes of Famine and Hunger Hotspots • Civil Wars • Drought • Government Incompetence
Life boat Ethics (same author as Tragedy of the Commons) Some lifeboats crowded & people keep falling out Some not crowded- could pick up the people in the water but Then the uncrowned boats would be crowded and unsafe and everyone could die ?