The Race to Feed the World Growing Human Population and the Green Revolution Although human population has slowed, we can still expect our numbers to swell to 9 billion by the middle of this century. For every 2 people living today there will be 3 in 2050 We must figure out a way to feed the 50% increase in people while protecting the integrity of soil, water, and ecosystems. This could involve approaches as diverse as organic farming and genetically modified crops

We are producing more food per person, but… Food Security 1960’s and Paul Ehrlich Our ability to produce more food has grown faster than the global population, however, largely because of political obstacles and inefficiencies in distribution, today 850 million people in developing countries do not have enough to eat. Every 5 seconds, somewhere in the world, a child starves to death Food Security: the guarantee of an adequate and reliable food supply available to all people at all times. Food security is the goal of agricultural scientists and policy makers. This depends on maintaining healthy soil, water and biodiversity. Starting in the 1960’s, scientists, including Ehrlich predicted widespread starvation and a catastrophic failure of agricultural systems, arguing that the human population could not continue to grow without outstripping its food supply. We surprisingly did better than these predictions. The number of people starving in less developed nations has actually decreased by over 100 million since 1970. We have reduced hunger by half, from 26% of the population in 1970 to 13% today. We have done this by increasing our ability to produce food.

How did we do it? Devoting more fossil fuel energy to agriculture Planting and harvesting more frequently Increasing the use of irrigation, fertilizer, and pesticides Increasing the amount of cultivated land Developing (through crossbreeding and genetic engineering) more productive crop and livestock varieties We have achieved these advances in part by increasing our ability to produce food However, with grain crops, the world’s staple foods, we are producing slightly less food per person each year. Since 1985, world grain production per person has fallen by 9%. Moreover, the world’s soils are in decline, and nearly all the planet’s arable land has already been claimed.

We face undernourishment, overnutrition, and malnutrition “The quantity of food a person eats in important for health, and so is the quality of food.” Although many people lack access to adequate food, others are affluent enough to consume more than is healthy. Undernourished: receive less than 90% of their daily caloric needs, live in the developing world. For most people who are undernourished, the reasons are economic. 1/5 of the world’s people live on less than $1 per day, and over half live on less than $2 per day. Overnutrition: people in the developed world receive too many calories each day. In the U.S.: food is available in abundance, junk food is cheap, and people tend to lead sedentary lives with little exercise. More than three out of five adults are technically overweight and over one out of four is obese. Worldwide, obesity now affects over 300 million people. Hunger is a problem even in the United States, where the U.S. Department of Agriculture has classified 31 million Americans as “food insecure”, lacking the income required to procure sufficient food at all times.

Malnutrition Kwashiorkor Bloating of the abdomen Deterioration and discoloration of hair Mental disability Immune suppression Developmental delays Anemia Reduced growth Malnutrition: a shortage of nutrients the body needs, occurs when a person fails to obtain a complete complement of vitamins and minerals. Malnutrition can afflict both undernourished and overnouristed individuals and it can lead to disease When people eat a high-starch diet, but not enough protein or essential amino acids, then kwashiorkor results. Children who have recently stopped breast-feeding are most at risk for developing kwashiorkor, which causes bloating of the abdomen, deterioration and discoloration of hair, mental disability, immune suppression, developmental delays, anemia, and reduced growth. Protein deficiency together with a lack of calries can lead to marasmus, which causes wasting or shriveling among millions of children in the developing world

Quick Note Check What kinds of techniques have people employed to increase agricultural food production? What did Paul Ehrlich and other scientists predict and how are their predictions not entirely correct? What is the difference between undernourishment, overnutrition, and malnutrition? Switch papers and highlight the answers to these questions in your peer’s notes. If you can locate answers to all three questions, place a 3/3 on the top of their page.

The Green Revolution

The “Green Revolution” Boosted Agricultural Production Mid and late 20th C Norman Borlaug—1940’s The desire for greater quantity and quality of food for our growing population led in the mid-and late-20th century to the green revolution. Realizing that farmers could not go on indefinitely cultivating more land t increase crop output, agricultural scientists devised methods and technologies to increase crop output per unit area of existing cultivated land. Industralized nations dramatically increased their per-area yields The average hectare of U.S. cornfield during the 20th C upped its corn output fivefold Many thought this would end starvation in developing nations Norman Borlaug (1940’s): The transfer of technology to the developing world that marked the green revolution began in the 1940’s with Borlaug, U.S. agricultural scientists who introduced Mexico’s farmers to a specially bred type of wheat This strain of wheat produced large seeds heads, was short in stature to resist wind, was resistant to diseases, and produced high yields. Within two decades of planting and harvesting this specially bred crop, Mexico tripled its wheat production and began exporting wheat He won the Nobel Peace Prize for his work His work spread to India and Pakistan and helped transform agriculture there Soon many developing countries were increasing their crop yields using selectively bred strains of wheat, rice, corn and other crops from industialized nations

Benefit vs. Harm Benefits of the Green Revolution Harm from the Green Revolution Intensified use of already cultivated land reduced the pressures to convert additional natural lands for new cultivation. Between 1961 and 2003, food production rose 150% and population rose 100%, while area converted for agriculture increased only 10% Prevented some degree of deforestation and habitat conversion Intensive application of water, fossil fuels, inorganic fertilizers, and synthetic pesticides worsened pollution, erosion, salinization, and desertification Monocultural planting has reduced biodiversity over huge areas Along with new grains, developing nations imported the methods of industrialized agriculture They began applying large amounts of synthetic fertilizers and chemical pesticides on their fields, irrigating crops with generaous amounts of water, and using heavy equipment powered by fossil fuels From 1900-2000, humans expanded the world’s total cultivated area by 33% while increasing energy inputs into agriculture by 80 times. Allowing farmers to harvest more corn, wheat, rice, and soybeans from each hectare of land Intensive agricultures saved millions in India from starvation in the 1970’s Turned nations into exporters of grain Monocultures Many fewer wild organisms are able to live in monocultures than in native habitata or in traditional small-scale polycutures When all plants in a field are genetically similar all will be equally susceptible to viral diseases, fungal pathogens, or insect pests that can spread quickly from plant to plant Monocultures bring significant risks of catastrophic failure Monocultures have also contributed to a narrowing of the human diet. (Globally, 90% of the food we consume now comes from just 15 crop species and eith livestock species) The nutritional risks of such dietary restriction have been alleviated by the fact that expanded global trade has provided many people access to a wider diversity of foods from around the world. However, this has benefited wealthy people far more than poor people.

Quick Note Check What is the “Green Revolution”? How did agricultural scientist Norman Borlaug help inaugurate the green revolution? How is the green revolution both a benefit and harm to society?