FEEDING THE WORLD

E N V I R O N M E N T A L S C I E N C E C H A P T E R 1 5 S E C T I O N 1

FEEDING THE WORLD

• Famine • Widespread starvation caused by a shortage of food.

• Occurred in 1985 in Ethiopia due to lack of rain, loss of soil, and war.

• By 2050, the world’s farmers will need to feed about 9 billion people.

• 50% more than they feed today.

HUMANS AND NUTRITION

• Food is necessary as a source of energy and to build and maintain body tissue.

• Major nutrients we get from food are carbohydrates, proteins, and lipids.

• Need smaller amounts of vitamins and minerals.

HUMANS AND NUTRITION

• Malnutrition • Do not consume enough Calories.

• • Do not eat a sufficient variety of foods to fulfill all of the body’s needs.

Many forms of malnutrition.

• Protein-energy malnutrition can affect the normal physical and mental development of children.

HUMANS AND NUTRITION

• Sources of Nutrition • Diet – the type and amount of food that a person eats.

• • Healthy diet maintains a balance of the right amounts of nutrients, minerals, and vitamins Grains are the most produced worldwide (carbohydrates).

HUMANS AND NUTRITION

• Sources of Nutrition

HUMANS AND NUTRITION

• Diets Around the World • People generally consume the same major nutrients and eat the same basic kinds of food.

• • Diets vary by region People in developed countries eat more food and a larger proportion of proteins and fats than those in less-developed countries.

HUMANS AND NUTRITION

• Diets Around the World

THE ECOLOGY OF FOOD

• Food Efficiency • The measure of the quantity of food produced on a given area of land with limited inputs of energy and resources.

• Basically, producing large amounts of food with little negative impact on the environment.

THE ECOLOGY OF FOOD

• Food Efficiency • • On average, more energy, water, and land are used to produce a Calorie of food from animals than to produce a Calorie of food from plants.

Animals are usually fed plant matter.

• 10% of the energy from the plant is stored in the animal.

• Land is more efficient when used to grow crops.

THE ECOLOGY OF FOOD

• Old and New Foods • Yield – the amount of food that can be produced in a given area.

• Researchers hope to improve the efficiency of food production by studying plants and animals with high yield.

• Want organisms that can survive in various climates and do not require large amounts of fertilizer, pesticides, or fresh water.

WORLD FOOD PROBLEMS

• Poverty • Malnutrition is almost entirely a result of poverty.

• • The world’s hungry are nearly all farm workers and subsistence farmers (grow enough only for local use).

Generally do not have access to enough water for irrigation.

• • Most live on an income of less than $1 per day.

Mainly in Africa, Asia, and the mountains of South America.

WORLD FOOD PROBLEMS

• More Income and More Food • Number of people living in extreme poverty has declined by nearly a half billion since 1980.

• • Rapid economic development in East Asia (China and India).

Grain production has not grown as fast as the population.

WORLD FOOD PROBLEMS

• More Income and More Food

THE GREEN REVOLUTION

• Between 1950 and 1970, Mexico increased its production of wheat eight-fold and India doubled its production of rice, without increasing the area of farmland used.

• New varieties of grain allowed this.

• Mostly from large farms.

• Still not improving much for subsistence farmers.