Transcript Document

Food, Soil, and Pest Management
Chapter 12
12-1 What Is Food Security and
Why Is It Difficult to Attain?
 Concept 12-1A Many of the poor suffer health
problems from chronic lack of food and poor
nutrition, while many people in developed countries
have health problems from eating too much food.
 Concept 12-1B The greatest obstacles to
providing enough food for everyone are poverty,
political upheaval, corruption, war, and the harmful
environmental effects of food production.
Many of the Poor Have Health Problems
Because They Do Not Get Enough to Eat
 Food security – means that every person in a
given area has daily access to enough nutritious
food to have an active and healthy life.
 Global food production has stayed ahead of
population growth.
• However :
• One of six people in developing countries cannot grow
or buy the food they need.
 Food insecurity – living with chronic hunger and
poor nutrition.
Key Nutrients for a Healthy Human Life
 We need large amounts of macronutrients
• (protein, carbohydrates, and fats)
 We also need smaller amounts of micronutrients
• (vitamins such as A,C, and E and various minerals)
Many People Suffer from
Chronic Hunger and Malnutrition
 Some people cannot meet their basic energy needs
• Chronic undernutrition or hunger
 Others lack proteins and key nutrient needs
• Chronic malnutrition
 The root cause of hunger and malnutrition is poverty.
• In 2006, 862 million were undernourished worldwide.
• A 2005 estimate says 6 million children die annually from
undernutrition or nonfatal diseases made worse by their
poor diet.
Many People Do No Get
Enough Vitamins and Minerals
 One in three people has a deficiency of one or
more vitamins and minerals, especially:
• iron – anemia
• vitamin A – blindness
• iodine – goiter or enlarged thyroid gland
 Can lead to deafness
 Famine – a shortage of food in an
area along with mass starvation,
economic and social chaos
• Usually caused by crop failures
from drought, flooding, war, or
other catastrophic events
Many People Have Health Problems
from Eating Too Much
 Overnutrition – excess calories and lack of exercise
can lead to reduced life quality, poor health, and
premature death…same as undernutrition
 A 2005 Boston University study:
• 60% of American adults are overweight
• 33% are obese
 Americans spend $42 billion a year
trying to lose weight.
 Estimates are that $24 billion per year would
eliminate world hunger.
12-2 How Is Food Produced?
 Concept 12-2A We have sharply increased crop
production using a mix of industrialized and
traditional agriculture.
 Concept 12-2B We have used industrialized and
traditional methods to greatly increase supplies of
meat, fish, and shellfish.
Food Production Has Increased Dramatically
 Wheat, rice, and corn provide more than half of
the world’s consumed calories
 Fish and shellfish are an important source of food
for about 1 billion people mostly in Asia
 Of all the biodiversity on the planet, only 14 plant
and 9 animal species make up 90% of the world’s
consumed calories.
Food Production Has Increased Dramatically
 Three systems produce most of our food:
• Grain from croplands: 77%
• Meat from rangelands, pastures, and feedlots: 16%
• Fish from fisheries/Aquaculture: 7%
 Dramatic increase in global food production since 1960.
• Why?
• Technological advances
• More sophisticated farming techniques
• Expanded use of inorganic chemical fertilizers, irrigation,
pesticides, high-yield crops
• Intense farming methods, densely populated feedlots,
breeding/growing pens, aquaculture ponds or ocean cages
Two Types of Agriculture
 Industrial Agriculture (High Input Agriculture)
• A relatively small group of farmers produce large
quantities of a single crop or livestock
• Mostly in developed countries
 Traditional Agriculture (Low Input Agriculture)
• Traditional subsistence agriculture
• Produces enough crops or livestock to feed family
• Traditional intensive agriculture
• Produces enough crops or livestock to feed the
farmer’s family and maybe some to sell
• Mostly in developing countries
Industrialized Crop Production Relies on
High-Input Monocultures
 About 80% of the world’s food supply is produced by
industrialized agriculture.
• Goal is to steadily increase crop yield
• Uses large amounts of fossil fuel energy, water, commercial
fertilizers, and pesticides to produce monocultures.
 Plantation agriculture primarily in tropical developing
countries (bananas, coffee, sugarcane)
• Cash crops – crops intended for sale, not consumption or animals
Traditional Agriculture Often Relies on
Low-Input Polycultures
 Many farmers in developing countries grow a variety
of crops on the same plot of land
• Polyculture: different plants are grown together
 Limited technology, limited equipment, limited impact
on the environment
 Slash-and-burn agriculture – burning underbrush to
provide nutrients to the soil
A Closer Look at Industrialized
Crop Production
 The Green Revolution represents the 88% increase
in food production per unit of area since 1950.
• Monocultures of high-yield key crops
• Selectively breed or genetically engineered crops
• Large inputs of fertilizers, pesticides, water
 The Second Green Revolution involves fast
growing rice/wheat bred for tropical regions.
 Early in the century, one American farmer could
produce food for 2.5 people.
 By 1999, a single farmer could feed over 130 people.
A Closer Look at Industrialized
Crop Production
 Since 1950, high-input agriculture has produced
more crops per unit of land.
• Grain production has tripled during this timeframe
 Why has per Capita grain production gone down
since the early 1980’s?
Crossbreeding and Genetic Engineering Can
Produce New Crop Varieties
 Gene Revolution – increased crop yields, as a
result of mixing organisms’ genes
• Artificial selection has been used for centuries to
develop genetically improved varieties of crops.
• Genetic engineering develops improved strains at
an exponential pace compared to artificial
selection.
• Add beneficial genes
• Delete negative genes
Crossbreeding and Genetic Engineering Can
Produce New Crop Varieties
 Age of Genetic Engineering
• developing crops that are
resistant to:
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Heat and cold
Herbicides
Insect pests
Viral diseases
Drought
Salty or acidic soil
 Controversy has arisen over
the use of genetically modified foods (GMF’s).
• Critics fear that we know too little about the long-term
potential harm to human health and the environment.
Meat Production and Consumption
Have Grown Steadily
 Meat production increased fourfold from 1961–2007
 Industrialized livestock production:
• Densely populated feedlots are common
• System uses a lot of energy and water and produce
huge amounts of animal waste
Industrialized Meat Production Has Harmful
Environmental Consequences
Fish and Shellfish Production
Have Increased Dramatically
 Aquaculture – raising large numbers of fish and
shellfish in ponds and cages
• world’s fastest growing type of food production.
 Fish farming involves cultivating fish in a controlled
environment and harvesting them in captivity.
Producing Fish Through Aquaculture Can
Harm Aquatic Ecosystems