Transcript Oct25NutritionFood

Environmental Science
PowerPoint Lecture
Principles of Environmental
Science - Inquiry and Applications,
1st Edition
by William and Mary Ann Cunningham
Chapter 7 - Topics
• Nutrition and Food Supplies
• Major Food Sources
• Introduce Soils (covered in book)
•
•
•
•
Ways We Use and Abuse Soil
Other Agricultural Resources
New Crops and Genetic Engineering
Sustainable Agriculture
Objectives of Chapter 7
• Describe world food supplies and some
causes of chronic hunger in midst of growing
food surpluses
• Explain some major human nutritional
requirements and consequences of nutrient
deficiencies
• Differentiate between famine and chronic
under-nutrition, and understand relation
between natural disasters and social and
economic forces triggering food shortages
Historical view of health – strong
environmental links
Field macrobioarchaeology – looking at indicators of health by examining
skeletons (e.g. cemetaries) for 7 basic indicators of health, in the western
hemisphere from 5000 BC to late nineteenth century (ref: The Backbone of History. Health and Nutrition in the
Western Hemisphere. Edited by Richard H. Steckel and Jerome C. Rose. Cambridge University Press. 2002) .
•Age at death
•Stature
•Arthritis
•Dental health – dental decay and tooth loss indicate nutrition
•Osteoporosis – indicate degree of regular strenuous activity, quality of life
•Trauma. Patterns healed fractures indicate activities including living on difficult
terrain, hazardous occupations, extent of warfare, interpersonal violence
•Infections (extracting DNA from pathogens to identify) – differences in contact with
bacteria & level of resistance. People living larger groups more problems infections
Spanish Conquest traumatic for history of natives in
Ecuador - introduction of Old World diseases to population not getting enough
food (Book reference: The Backbone of History. Health and Nutrition in the Western Hemisphere. Edited by Richard H.
Steckel and Jerome C. Rose. Cambridge University Press. 2002) :
1524-1527 smallpox epidemic; 1531-1533 measles,
possibly plague; 1546 plague, possibly typhus; 1558
smallpox, measles, possibly influenza; 1585-1591
smallpox, measles, possibly mumps; 1604 unidentified
epidemic; 1606 diphtheria; 1611 measles, and typhus;
1612 scarlet fever, measles, typhus; 1614 typhus,
diphtheria; 1618 measles, dysentery; 1634 typhus; 16441645 German measles, diphtheria; 1648-1649 smallpox,
german measles; 1667 typhus; 1676-1677 smallpox; 1680
plague; 1683 plague etc.
Implications of examining over 13,000
skeletons and health index: connection
between political development and
agriculture, Steckel & Rose 2002 said
“life became “nasty, brutish and
short” for the typical person with the
rise of agriculture, government and
urbanization. The hunter-gatherers
and those living in dispersed
settlements were the healthiest
groups” (
Book reference: The Backbone of History. Health and Nutrition in the Western
Hemisphere. Edited by Richard H. Steckel and Jerome C. Rose. Cambridge University Press. 2002)
Environmental Health Hazards with
Non-sustainable Industrialization
In some parts of Eastern Europe & former USSR, ~ 90%
children suffer from environmentally linked diseases.
Iron deficiency anemia,
Vitamin deficiencies,
Mineral deficiencies,
Toxicities, Poor resistance
to disease
Importance of Diet
• At least half of all Americans are considered
overweight.
• Strong correlation between cardiovascular
disease and the amount of salt and animal
fat in one’s diet
• Fruits, vegetables, whole grains, complex
carbohydrates, and dietary fiber have
beneficial health effects.
• Eating too much food has negative effects
on health.
Part 1: Nutrition, Food Supplies
World grain production 1950-2000
Average daily
diet:
1950 = 2,000
2000 = 3,500
calories / person
2002 India –enough
food but cities 36%
children stunted,
40% underweight
1 billion people chronically
undernourished
All ofEnergy
these Pyramid
are
food sources for
humans
Cunningham, Cunningham 2004
What is a
decomposer
MUSHROOMS
food source for CHEESE
humans?
WINE, BEER
Mycorrhizal –
symbiotic
relationships
between fungus
and tree.
Similar to truffles
collected using pigs,
dogs
Sporocarps tasty
and favorite of
humans –
Japanese,
Germans etc.
will pay a lot of
money for them
Part 1: Nutrition, Food Supplies
World food supply 1960-1998
Asia
Relative
food
production
by regions
Lat Amer
World
Africa
Former
Soviet
Union
Part 1: Nutrition, Food Supplies
In richer countries, the most common dietary problem
is over-nutrition (too many calories).
Average daily caloric
intake in North America
and Europe is 3,500
calories (1/3 more than
needed to be healthy)
~ 20% Americans are
over weight (10/2002
data - a third are over
weight)
http://www.nordictrack.com/cgibin/ncommerce3/ExecMacro/product/nt/product_v4.d2w/report?prmenbr=153&prrfnbr=105197&cgrfnbr=46526&rootcat
=46525
Part 1: Nutrition, Food Supplies
• Sub-Saharan Africa:
food production not
kept pace with rapid
population growth
(reasons: Droughts,
War, Poverty,
Government
mismanagement)
• In sub-Sahara, 35
out of 40 countries
had decreasing food
production last 20
years
Food Security
• Food security - the ability to obtain
sufficient food on a day-to-day basis
• About 800 million people chronically hungry (200
million are children) – 1 in 5 in developing world
• Chronic undernourishment in children leads to:
permanently stunted growth, mental retardation,
other social and developmental disorders
• Higher incidence of infectious diseases when
undernourished
• Poverty is the greatest threat to food security
• Within families that don’t get enough to eat,
women and children have the poorest diets
Countries at risk for food shortages –
high risk in orange color, low risk in white
High
Risk
High
Risk
Little Risk
Greatest risk: sub-Sahara Africa, Southeast & South
Asia, parts of Latin America.
Little risk: US, Canada, Europe, Japan, Australia
Countries at risk for food shortages – high risk
= orange color, low risk = white
What BIOMES are found in locations with
the greatest risk for food shortages?
What BIOMES are found in areas with little
risk for food shortages?
Essential Nutrients
• Malnourishment - a nutritional imbalance
caused by a lack of specific dietary components
or an inability to utilize essential nutrients
• Richer countries eat too much meat, salt, fat and
not enough fiber, vitamins etc since foods are so
processed
• The number of people with allergies has gone up
and has not been helped by the chemicals
(hormones) used to speed up the rate at which
animals accumulate biomass (the food source).
Essential Nutrients
• Starchy foods (corn, polished rice) tend to
be low in several essential nutrients
• Protein deficiency diseases - kwashiorkor,
marasmus
• Iron deficiency - anemia - most severe in
India (80% pregnant women)
• Iodine deficiency - goiter, hyperthyroidism;
HOW DEAL WITH THIS DEFICIENCY?
WHY DO DEFICIENCIES EXIST
– esp. when caloric input high?
goiter
Kwashiorkor
– West African
word for
displaced child
Marasmus –
Greek word ‘to waste
away’ (diet low in
calories, proteins)
http://www.healthcentral.com/mhc/img/img1164.cfm
Famines: Some Causes
• Environmental
conditions drought, insects,
natural disasters
• National politics corruption,
oppression
• Armed conflict
• Economics - price
gouging, poverty,
landlessness
Dealing with
Underlying
Causes of
Famine?
Famine causes
people to use
up their
productive
Aid policies of rich countries often capacity (killing
serve to: get rid of surplus food,
animals, eating
without dealing with root causes of stored grains),
starvation; set up feeding camps – mass
not deal growing own crops, etc.
migrations
Part 2: Major Food Sources
Of 1,000s edible plants & animals,
humans use only:
•
•
•
•
•
~12 types seeds, grains
3 root crops
~20 fruits, vegetables
6 mammals
2 domestic fowls, few fish
Part 2: Major Food Sources
Crops
• Three major crops - wheat, rice, maize
(wheat & rice = 60% of calories
consumed globally)
• Mountains & High latitudes - potatoes,
barley, oats, rye
• Warm, wet areas (tropics) - roots and tubers
• Dry regions Africa – sorghum, millet
(drought resistant)
• Fruits and vegetables
Meat, Milk, and Seafood
• Milk and meat highly prized, but
distribution inequitable
• About 90% of the grain grown in North
America is used to feed cattle, hogs,
poultry, and other animals!
• Seafood - important protein source in
many countries - threatened by
overharvesting and habitat destruction
Eating a
Balanced
Diet
USDA Food
Pyramid
What most
eaten in
past?
The Challenge of Choosing Foods – Variety!
Soil Profile
You
cannot
just grow
any crop
– the soil
type
limits this
capacity
Part 1: Nutrition, Food Supplies
• Asia experienced
Limited
most
rapid land base available
increase
in crop
means
conversion
of
production (esp.
China,
Indonesia
natural
systems to crops
tripled food
production in less
Remember
10% of globe
than
decade).
• Ex.
In Indonesia, land
in
terrestrial
area used
4 years had worlds
biggest
riceto grow agricultural
today
reserves from
crops,
being
worlds28% in US
Malaysia, palm oil
biggest importer
Few options for what
crops to grow for food
because of limitations of
the soil – can be limited
by low nutrients, toxins,
high salts
Land conversion for food
production is not always
a good idea
Photo: K Vogt
Cassava /
manioc,
Brazilian
Amazon,
TROPICAL
FOREST
Values of
international
organizations
attempt stop
shifting
agriculturalists in
Amazon to increase
carbon storage in
forests, place
farmers in intensive
agricultural farms
(nutrient poor soils
would not allow this
to be sustainable)
Amazon – water buffalo owned by large landowners with economic
power destroying the varzea (floodplains) used by indigenous people