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We can’t solve problems by using the same kind of thinking we used when we created them. –Albert Einstein 7-1 Global Trends in Food and Nutrition • Food production has been transformed from small-scale, diversified, family operations to expansive farms of thousands of hectares, growing one or two genetically modified crops, with abundant inputs of fuel and fertilizer, for a competitive global market. 7-2 Hunger around the world 7-3 Food security is unevenly distributed • Four decades ago, hunger was one of the world’s most prominent, persistent problems. • In 1960, nearly 60 percent of people in developing countries were chronically undernourished, and the world’s population was increasing by more than 2 percent every year. • Today, some conditions have changed dramatically; others have changed very little. • The world’s population has risen from 3 billion to over 6.5 billion, but food production has increased even faster. 7-4 Food security is unevenly distributed… • Food security is the ability to obtain sufficient, healthy food on a day-to-day basis, is a combined problem of economic, environmental, and social conditions. • In wealthy countries such as the United States, millions lack a sufficient, healthy diet. • In the poorest countries, entire national economies can suffer from a severe drought, flood, or insect outbreak. 7-5 Famines usually have political and social roots • Globally, widespread hunger arises when political instability, war, and conflict displace populations, removing villagers from their farms or making farming too dangerous to carry on. • Famines are large-scale food shortages, with widespread starvation, social disruption, and economic chaos. 7-6 7-7 Eating Right to Stay Healthy • A good diet is essential to keep you healthy. • You need the right nutrients, as well as enough calories for a productive and energetic lifestyle. 7-8 A healthy diet includes the right nutrients • Malnourishment is a general term for nutritional imbalances caused by a lack of specific nutrients. 7-9 The Harvard food pyramid 7-10 Overeating is a growing world problem • Increasing world food supplies and low prices cause increasing overweight and obese populations. • In the U.S., and increasingly in Europe, China, and developing countries, highly processed foods rich in sugars and fats have become a large part of our diet. • Some 64 percent of adult Americans are overweight, up from 40 percent only a decade ago. About one-third of us are seriously overweight, or obese (generally considered to mean more than 20 percent over the ideal weight for a person’s height and sex. 7-11 The Foods We Eat • Of the thousands of edible plants and animals in the world, only a few provide almost all our food. 7-12 A boom in meat production brings costs and benefits • Because of dramatic increases in corn and soy production, meat consumption has grown in both developed and developing countries. • Meat is a concentrated, high-value source of protein, iron, fats, and other nutrients that give us the energy to lead productive lives. 7-13 Meat is a good indicator of wealth 7-14 Confined animal feeding operation (CAFO) 7-15 Seafood is both wild and farmed • Overharvesting and habitat destruction threaten most of the world’s wild fisheries. • The problem is too many boats using efficient but destructive technology to exploit a dwindling resource base. • Aquaculture is providing an increasing share of the world’s seafood. 7-16 Fish pins • Net pens anchored in nearshore areas allow spread of diseases, escape of exotic species, and release of feces, uneaten food, antibiotics, and other pollutants into surrounding ecosystems. 7-17 Increased production comes with increased risks • There are many environmental worries about this efficient production. – Land conversion from pasture to soy and corn fields raises the rate of soil erosion. – Constant use of antibiotics raises the very real risk of antibiotic-resistant diseases. 7-18 Other Agricultural Resources • Irrigation is necessary for high yields – Agriculture accounts for the largest single share of global water use. – Salinization: mineral salts accumulate in the soil due to evaporating water from irrigation. • Fertilizer boosts production – Much of the doubling in worldwide crop production since 1950 has come from increased inorganic fertilizer use. • Modern agriculture runs on oil • Pest control saves crops 7-19 How We Have Managed to Feed Billions • In the developed countries, 95 percent of agricultural growth in the twentieth century came from improved crop varieties (the green revolution) or increased fertilization, irrigation, and pesticide use, rather than from bringing new land into production. 7-20 The green revolution has increased yields • Most of this gain was accomplished by use of synthetic fertilizers along with conventional plant breeding: geneticists laboriously hand-pollinating plants and looking for desired characteristics in the progeny. • Starting about 50 years ago, agricultural research stations began to breed tropical wheat and rice varieties that would provide food for growing populations in developing countries. 7-21 Genetic engineering could have benefits and costs • Genetic engineering: splicing a gene from one organism into the chromosome of another. • Genetically modified organisms (GMOs): organisms with entirely new genes, and even new organisms, often called “transgenic” organisms. 7-22 Is genetic engineering safe? • The greatest danger is the ecological effects if these organisms spread into the native populations. • There are social and economic implications of GMOs. Will they help feed the world, or will they lead to a greater consolidation of corporate power and economic disparity? • Are GMO’s required if we hope to reduce malnutrition and feed eight billion people in 50 years. 7-23 Alternatives in Food and Farming • Soil conservation is essential – With careful husbandry, soil is a renewable resource that can be replenished and renewed indefinitely. – Water runoff can be reduced by grass strips in waterways and by contour plowing, plowing across the hill rather than up and down. – Terracing is shaping the land to create level shelves of earth to hold water and soil. 7-24 Soil conservation is essential 7-25 Consumer Choices Can Reshape Farming • You can be a locavore – Locavore: a person who consumes locally produced food. • You can eat low on the food chain – Since there is less energy involved in producing food from plants, you can reduce your impact by eating more grains, vegetables, and dairy and a little less meat. • You can eat organic, low-input foods – If you buy organic food, you are supporting farmers who use no pesticides or artificial fertilizers. 7-26