Transcript Feeding the World

Feeding the World
Chapter 14
Feeding the World
Chapter 14
14.1 Human Nutrition
• Macronutrients – provide energy to body.
– Ex. Carbohydrates, proteins, and fats.
• Micronutrients – provide the body with small amounts of
chemicals needed for biochemical reactions.
Humans need energy to carry out their life
processes.
Kilocalorie (Kcal) –
unit of measurement
for the energy
contained with in
macronutrients.
• Humans are omnivores (plant and animal)
•Human diets
should include
more vegetables
than meats.
Nutrition
• There are 8 Essential Amino Acids that must
be obtained by food.
• Carbohydrates – provide the body with the
quickest source of energy.
– EX. Bread, grain, or veggies
• Foods with complex carbohydrates are
starches.
Malnutrition
• Caused by the lack of a specific nutrient.
• A healthy vegetarian diet includes protein
from a combination of grains and legumes
(soy, bean, peanuts).
• Foods that come
from plants usually
lack some essential
amino acids.
14.2 World Food Supply
• More food is available per person than at
any point in history.
The Green Revolution
refers to a series of research, development,
and initiatives, occurring between the 1940s
and the late 1970s, that increased
agriculture production around the world,
beginning most markedly in the late 1960s.[
The Green Revolution
Characteristic
1. Development of new strains of wheat and rice,
the two main foods of the world.
The Green Revolution
Characteristic
2. Faster growth, resistance to disease, climate
diversity.
The Green Revolution
Characteristic
3. Crop yields can increase as much as 4 times
the normal yield.
The Green Revolution
Characteristic
4. Fertilizers and Modern Machinery.
The Green Revolution
Problem
Poor farmers can’t afford these advances so
they don’t make as much money for their
product.
Cash Crops
• A crop grown for the purpose of sale.
• Developing countries would rather export
crops for livestock than provide food for
their starving nation.
• Money is used to support government
(weapons and political leaders).
Food from the Water
• Increased harvesting of ocean fish has led to
endangerment of fish species.
• Aquaculture involves the controlled commercial
production of fish and mollusks.
• An alternative to fishing in the open oceans for
food is to raise fish in confined pools.
Fish Farm
Fish Farm
14.3 Improving Modern Farming
Techniques
• Modern farming 1 farmer can feed 78 people, 1850 1
farmer could feed 5.
• Industrialized Agriculture (I.A.)
– Highly efficient and
productive.
• I.A. uses large amounts of energy, pesticides, and
fertilizers.
• Agribusinesses – Farms run by large corporations.
• Large fossil fuels consuming equipment
replaced human powered tools.
Agribusinesses have several stages:
1. food production
2. packaging
3. transport.
Modern Farming Techniques
• Monoculture –
growing one or two
crops instead of a
variety.
• High amounts of
pesticides and fertilizers were necessary due to
the single crop. Growing only one crop drains
the soil and attracts a high concentration of
pests..
Problems with
Modern Farming
Techniques
1. Plants are vulnerable to the same diseases
2. Mineral depletion from the soil
3. Soil ability is reduced which decreases the
crop yield.
4. Overusing pesticides has lead to insect
resistance
Modern Farming Techniques
Historic Farming Techniques
14.4 Sustainable
Agriculture
Sustainable Agriculture
crop rotation, reduced
soil erosion, integrated
pest management,
and a minimal use
of soil additives.
Some Methods of Sustainable
Agriculture
1. Crop rotation – changing crop on a regular
cycle. 1 – 6 Years to prevent the minerals
from becoming depleted from the soil.
2. Cover Crops – nonfood plants grown
between growing seasons.
3. Return nitrogen naturally and prevent
erosion.
Some Negative Effects of Nonsustainable techniques:
1.
2.
3.
4.
5.
Soil Erosion
Deforestation
Desertification
Hunger
War
Reducing Erosion
1. Natural process by which valuable topsoil
and nutrients are carried away.
2. Drip irrigation delivers small quantities of
water at the root, reducing erosion by
water.
3. Reduced tilling can increase crop yields.
4. Extensive tilling is beneficial to the soil,
but it increases erosion from water and
wind.
Erosion
Pest
Management
1. IPM – Integrated
Pest Management
2. Reduces pesticides
by as
much as 90%.
3. Natural Predators – Wasps, ladybugs, and a
variety of viruses and bacteria.
4. Insects were becoming immune to insecticides
and crops were suffering.
5. Farmers using IPM have higher crop yields.