food and agriculture final.pptx - DrUnfried

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Food and Agriculture

Chapter 9

Tara Condren & Brian Corset (woops! Briana
Corso
)

Food & Nutrition


Increase in food supplies
corresponding to increase
in human numbers


Past 40 years


Population growth : 1.7%


World Food Production:
2.2%

Not Enough FOOD?!


1960: 60% of residents in
developing countries were
considered
chronically
undernourished


Not even 2,200 kcal per day
(average)!


If today’s food supply was
equitably distributed


2,800 kcal
per person per day


United States: too much food?!


Farmers PAID $$$$$ to NOT grow
crops!

HUNGER


852 million people


NOT ENOUGH FOOD


95% chronically undernourished
-

developing
countries


Transition Countries


Bad weather


Poor management


Social crises


Even in rich countries!

FALLING
AGRICULTURAL
PRODUCTION

Poverty


#1 threat to
food security

(ability to
obtain food daily)


Poorest Countries: hunger affects
almost EVERYONE


Other countries: specific
communities/families struggle .


How the family works:


Males


largest share & most
nutritious food


Women & children
-

poorest diet
(they need it the most!)


6 million children under 5 die every
year from hunger & malnutrition

The Future


Robert
Fogel

(Nobel Prize
-
winning economist):


Reducing hunger


$120 billion in economic growth


700 million people’s lives would improve


2003 UN World Food Summit


Reducing number of chronically undernourished from 850 million

400 million by 2015


WE ARE OFF TRACK!


47 countries
-

number of chronically underfed people has
INCREASED


Need to recognize the role of women!


50
-
70% of the farming


LAND, CREDIT, EDUCATION, ACCESS to MARKETS


Family
nutrition


FAMINES


Large
-
scale food shortages, massive starvation, social
disruption, and economic chaos


Mass migrations of the starving to refugee camps (food &
medical aid)


2005: 60 million people in 36 countries needed
emergency food aid


2004 Indian Ocean Tsunami


Politics


Economics


Bad Weather


Insect Outbreaks (ex/ the Locusts)


Natural Disasters

Crop
failures &
food
shortages

The RIGHT food!


We need proteins, vitamins, & certain trace minerals


Its not all about the calories!


Malnourishment
-

nutritional imbalance caused by
a lack of specific dietary components or an
inability to absorb or utilize essential nutrients


That’s not healthy!


Poor people cannot afford the
essentials!


FAO: nearly 3 billion (HALF
THE WORLD’S POPULATION
suffer from vitamin, mineral, or
protein deficiencies


Illness & Death OCCUR!


Reduced mental capacity,
developmental abnormalities, &
stunted growth

Mommy was right!


Anemia


Most common nutritional problem in
the world (2 billion people)


Eat more red meat, eggs, legumes &
green veggies!


Iodine Deficiency


Iodine: Synthesis of thyroxin (endocrine
hormone that regulates metabolism &
brain development


Causes goiter, stunted growth, and
reduced mental ability


Iodine added to salt in developed
countries

Goiter: swelling of thyroid
gland at the base of the neck


OFTEN CAUSED BY IODINE DEFICIENCY

There are Vitamins and
Minerals in every bite!


NOT in starchy foods!!!!


Maize (corn), polished rice, and
manioc (tapioca)
-

much of the
poor people’s diet


100
-
140 million children affected
by vitamin A deficiencies


350,000 go blind every year


Folic acid (yes in those dark, green
veggies) are VITAL for early fetal
development


Neurological problems


Microencephaly (small head)


Anencephaly (lacking a brain)


Protein Protein Protein!


Essential to growth & development


Kwashiorkor
-

a young child is displaced


and deprived of nutritious breast milk


when
a new baby is born


Young children eat cheap starchy food
-

lack
protein


Reddish
-
orange hair, puffy, discolored skin,
bloated belly


Marasmus


Diet low in calories & protein


Thin, shriveled: like a tiny, old, starving person


Let’s talk about obesity!


Rich Countries: 1/3 more calories than needed & too little
exercise


62% of all adult Americans are overweight


1/3 of adults are
obese

(seriously overweight: body mass
greater than 30 kg/m
2
)


Raises your risk of hypertension, diabetes, heart attacks,
stroke, gallbladder disease, osteoarthritis, respiratory
problems, and cancers


300,000 die per year in the USA from obesity
-
related illnesses


1
st

time in history
-

MORE overweight people THAN
underweight!







Trans Fat is not recommended


People will have proper nutrition if they combine this
food pyramid with regular, moderate exercise

The cream of the crop!


Wheat, rice, & corn (maize)


60% of calories consumed by humans come
from wheat & rice


Potatoes, barley, oats, & rye


staples in
mountainous regions & high latitudes


Fruits, Vegetables, and Vegetable Oils



High levels of vitamins, minerals, dietary
fiber, and complex carbohydrates

Beef & Milk


Protein
-
rich foods! (Meat & Dairy)


Rise in meat consumption in developing
countries


Increased soybean production in Brazil:
fueled the growth in meat consumption


North American livestock:


Concentrated animal feeding operations
(
CAFOs
):
diet rich in grain, oil & protein
-

fattens animals quickly & produces meat
preferred by many consumers


680 million metric tons of cereals
-

livestock
feed each year


Beef & Milk...continued...


Social & Environmental concerns


Local air & water pollution


500 million metric tons of manure annually


Contaminates groundwater supplies


Respiratory Illnesses


Animal Wastes (ex/hog farms) stored in lagoons


If they leak/rupture

poison local surface water


Deoxygenates the water, kills millions of fish, can
create a “dead zone”


25 million pounds of antibiotics fed to animals in US

Bubba Gump


140 million metric tons of seafood eaten every year


¾ of world’s edible ocean fish, crustaceans, & mollusks
species
-

IN DECLINE!


4 million boats harvesting wild fish exceed sales by $50
billion


Aquaculture (growing aquatic species in net pens or
tanks)


¼ of the world’s seafood


Polyculture systems help reduce aquaculture problems


Ex/ China: ponds & rice paddies to raise fish




FARM POLICY


Rich Countries: pay about $350 billion to their farmers


U.S. Farm Bill: $180 billion in payments over the next ten years for
American farmers


Corn, wheat, cotton, rice & soybeans


Milk, sugar, and peanuts


Subsidies: maintain “family farms”


10% of all farms received 70% of all support


Agricultural Subsidies


Encourage surpluses


American farmers : sell products 20% below actual cost of production


World Trade Organization (WTO) ruled American farm subsidies illegal!

SURPRISE! Case Study Time!


A Soybean Revolution


South America: The Cerrado (savanna Bolivia

Paraguay)


Inexpensive land, new crop varieties, government policies


Red
-
iron rich soils: ACIDIC & poor in nutrients


Humid climate


insects & plant diseases; OH MY!


Lime & Phosphorus
-

4x the previous yield of soybeans, maize, cotton & others


60 million acres planted with soy!


Brazil:
Producing soy for less than half the cost in the U.S.


China: consuming more soy (1/3 of total global soy shipments)


Forest Destruction Crisis


70% of all arable land is owned by less than 3% of the population


74 year old
-

Sister Dorothy Sang shot by gunmen hired by rancher!


Resented her advocacy for native people, workers, and environmental
protection

Soil: A renewable source


Has a terrible reputation!


SOIL
-

complex mixture of
weathered mineral
materials from rocks,
partially decomposed
organic molecules, and a
host of living organisms


Over 15,000 different types
of soils in the U.S.


Parent material, time,
topography, climate &
organisms on soil formation


It’s a mixture!


Soil:


Half mineral; the rest: plant &
animal residue, air, water & living
organism


Particle size affects the soil!


Ex/ heavy VS light soil


Heavy: high clay content


Light: mostly sand or silt


Sandy loam: best cultivating soil!


Majority of organic material in
soil:


Humus: sticky, brow, insoluble
residue from partially
decomposed bodies of dead
plants & animals


Develops the structure of soil


Living Organisms’ Importance


Create structure, fertility, & tilth!


Soil organism: close to surface


Thousands of species & billions of individual organisms


1 gram of soil: hundreds of millions of microscopic cells


What smells so good?!


Actinomycetes
-

bacteria that grow in fungus like strands &
give us the antibiotics streptomycin & tetracyclines


Micorrhizal Symbiosis


Roots & fungi

Crazy Animals!

Mind the Worms!




Animals be wildin!


Soils are Layered


Most soils are stratified into horizontal layers called soil horizons


They reveal much about the history and usefulness of the soil


Soil profile


The thickness, color, texture, and composition of each horizon are
used to classify the soil


The soil surface is covered with a layer of leaf litter, crop residues, or
other decomposed organic material


This is known as the O horizon


Topsoil


Below the O horizon


Composed of mineral particles mixed with organic material


Regolith


It is beneath the subsoil


Made of weathered rock fragments with very little organic material



Soils are classified according to
their structure and composition:


In the United States, soils are classified into 12 soil orders:


Mollisols

and
alfisols


Spodosols


Oxisols

and
ultisols


Aridosols


Andisols


Vertisols


Histosols


Entisols

and
inceptisols


Gelisols


WAYS WE USE AND ABUSE SOIL



Only about 12.5% of the earth’s land area is currently in
agricultural production


Parts of the world lack suitable soil, topography, water, or
climate to sustain our levels of productivity


The cropland available for agriculture is shrinking


1970
-
global average of 0.38 ha per person


2002
-
0.21 ha per person


2030
-
0.16 ha per person


Asia
-
30 years from now
-
0.09 ha per person


The largest increases in cropland over the last 30 years
occurred in South America and Oceania where forests and
grazing lands are rapidly being converted to farms


Land degradation reduces
agricultural potential


The International Soil Reference and Information Centre
in the Netherlands estimates that every year 3 million ha
of cropland are ruined by erosion, 4 million ha are
turned into deserts, and 8 million ha are converted to
nonagricultural uses such as homes and highways


We generally consider the land degraded when the soil is
impoverished or eroded, water runs off or is
contaminated more than is normal, vegetation is
diminished, biomass production is decreased, or wildlife
diversity diminishes


Water and wind erosion provide the motive force for the
vast majority of all soil degradation, worldwide


Soil erosion is widespread


Erosion is an important natural process, resulting in
the redistribution of the products of geologic
weathering, and is part of both soil formation and
soil loss


Erosion is a disaster only when it occurs in the
wrong place at the wrong time


The total annual soil loss from croplands is thought
to be 25 billion metric tons


About twice that much soil is lost from rangelands,
forests, and urban construction sites each year


Wind and water are the main
agents that move soil



A thin layer taken off the land surface is called sheet erosion


Rill erosion
-
the process when little rivulets of running water gather together and cut small
channels in the soil


Most soil loss on agricultural land is sheet or rill erosion


Summer dust storms in the Sahara Desert of North Africa carry about 1 billion tons of soil in
massive airborne dust plumes over the Atlantic and Mediterranean every year


Some of the highest erosion rates in the world occur in the United States and Canada


Intensive farming practices are largely responsible for this situation


Row crops, such as corn and soybean, leave soil exposed for much of the growing season


Continuous monoculture cropping can increase soil loss tenfold over other farming patterns


Soil study in Iowa showed that a three
-
year rotation of corn, wheat, and clover lost an
average of only 6 metric tons per hectare

Deserts are spreading
around the world


According to the United Nations, about one
-
third of the earth’s
surface and the livelihoods of at least one billion people are
threatened by desertification


Contributes to food insecurity, famine, and poverty


Rangelands and pastures, which generally are too dry for
cultivation, are highly susceptible to desertification


80% of the world’s grasslands are suffering from overgrazing
and soil degradation, and three
-
quarters of that area has
undergone some degree of desertification


China is trying to fight the spread of deserts with an ambitious
ecological restoration program


Since 1985, more than 40 billion trees have been planted
over an area the size of Germany


OTHER AGRICULTURAL
RESOURCES

All plants need water to grow


Agriculture accounts for the largest single share of global water use


About two
-
thirds of all fresh water withdrawn from rivers, lakes, and
groundwater supplies is used for irrigation


Farmers often tend to over
-
irrigate because water prices are relatively low and
because they lack the technology to meter water and distribute just the amount
needed


In the United States and Canada, many farmers are adopting water
-
saving
technologies such as drip irrigation or downward
-
facing sprinklers


Excessive use not only wastes water; it often results in water
-
logging


Waterlogged soil is saturated with water, and plant roots die from lack of
oxygen


Salinization

occurs particularly when soils in dry climates are irrigated with
saline water



Plants need fertilizer


In addition to water, sunshine, and carbon dioxide, plants need
small amounts of inorganic nutrients for growth


The major elements required by most plants are nitrogen,
potassium, phosphorus, calcium, magnesium, and sulfur


Farmers may over fertilize because they are unaware of the
specific nutrient content of their soils or the needs of their crops


What are some alternative ways to fertilize crops?


Manure and green manure (crops grown specifically to add
nutrients to the soil) are important natural sources of soil
nutrients


Interplanting

or rotating beans or some other leguminous crop
with such crops as corn and wheat are traditional ways of
increasing nitrogen availability


Farming consumes energy


Farming as it is generally practiced in the industrialized countries is
highly energy
-
intensive


Fossil fuels supply almost all of this energy


After crops leave the farm, additional energy is used in food
processing, distribution, storage, and cooking


It has been estimated that the average food item in the American diet
travels 2,000 km between the farm that grew it and the person who
consumes it


Altogether the food system in the United States consumes about 16%
of the total energy we use


Farmers could assist in moving to a renewable energy future by
growing energy crops that can be converted into
biofuels


Encouraged construction of corn
-

or soy
-
based ethanol factories


Mixing ethanol with gasoline helps reduce air pollution

NEW CROPS AND
GENETIC ENGINEERING


Many new or unconventional varieties might be
valuable human food supplies, especially in areas
where conventional crops are limited by climate,
soil, pests, or other problems


Winged bean


A perennial plant that grows in hot climates


Edible, resistant to diseases, and enriches the soil


Tricale


A hybrid between wheat and rye that grows in
light, sandy, infertile soil

The “green revolution” produced
dramatic increases in crop yields


A century ago, when all corn in the United States was open
-
pollinated,
average yields were about 25 bushels per acre


In 1999, average yields from hybrid maize were around 130 bushels
per acre


Most of this gain was accomplished by conventional plant
breeding


Geneticists laboriously hand
-
pollinating plants, moving selected genes
from one variety to another


Starting about 50 years ago, agricultural research stations began to
breed tropical wheat and rice varieties that would provide food for
growing populations in developing countries


It is one of the main reasons that world food supplies have more
than kept pace with the growing human population over the past
few decades


Poor farmers who can’t afford the expensive seed, fertilizer, and water
required to become part of this movement, usually are left out of the
green revolution


May be driven out of farming altogether


Genetic engineering uses molecular
techniques to produce new crop varieties


Genetic engineering


Involves removing genetic material
from one organism and splicing it
into the chromosomes of another


Has the potential to greatly increase
both the quantity and quality of our
food supply


It is now possible to build entirely new
genes, and even new organisms


GMOs

(genetically modified organisms


Research is now underway to improve
yields and create crops that resist
drought, frost, or diseases


Genetic Engineering
Continued


Other strains are being developed to tolerate salty, waterlogged, or low
-
nutrient soils


All of these could be important for reducing hunger in developing countries


Plants that produce their own pesticides might reduce the need for toxic chemicals


Attempts to remove specific toxins or allergens from crops also could make our food
safer


Crops such as bananas and potatoes have been altered to contain oral vaccines that can
be grown in developing countries where refrigeration and sterile needles are
unavailable


It may soon be possible to create animals with human cell
-
recognition factors that could
serve as organ donors


Opponents
-
could create a host of problems, some of which we can’t even
imagine


GMO’s

might escape and become pests or they might interbreed with wild relatives


This technology may be available only to the richest countries or the wealthiest
corporations, making family farms uncompetitive and driving developing countries
even further into poverty


About 82% of all soybeans, 71% of the cotton, and one
-
quarter of all corn grown in the
United States are
GMOs


Most
GMOs

have been engineered for
pest resistance or weed control


Biotechnologists recently have created plants with
genes for endogenous insecticides


Allows farmers to reduce insecticide spraying


Arizona cotton farmers report reducing their use of
chemical insecticides by 75%


Is genetic engineering
safe?


In 2002, while millions of its people faced famine, Zambia’s
government refused to accept thousands of tons of genetically
modified corn from the United States, claiming that it might be
unsafe for human consumption


Most European nations have bans on genetically engineered
crops


The first genetically modified animal designed to be eaten by
humans is an Atlantic salmon containing extra growth
hormone genes from an oceanic pout


Greatest worry: the ecological effects if the fish escape from
captivity


People argue that the government should be more careful
when it comes to genetically engineered animals


SUSTAINABLE
AGRICULTURE


Sustainable agriculture


Regenerative farming, or
agroecology
, all of
which aim to produce food and fiber on a
sustainable basis and repair the damage caused
by destructive practices


Soil conservation is
essential


Soil is a renewable resource that can be replenished and
renewed indefinitely


There is evidence that American soil conservation
programs are having a positive effect


Water runoff can be reduced by leaving grass strips in
waterways and by contour plowing


Plowing across the hill rather than up and down


Strip farming


Planting of different kinds of crops in alternating strips along the
land contours


When one crop is harvested, the other is still present to protect the soil
and keep water from running straight downhill


Terracing


Involves shaping the land to create level shelves of earth to hold water
and soil


This is an expensive procedure, requiring either much hand labor or
expensive machinery


Soil Conversion Continued


Providing Ground Cover


Annual row crops such as corn or beans generally cause the highest
erosion rates because they leave soil bare for much of the year


Cover crops


Mulch


Reduced Tillage


Finding that less plowing and cultivation often makes for better
water management, preserves soil, saves energy, and increases crop
yields


There are several major reduced tillage systems


Minimum till involves reducing the number of times a farmer disturbs the soil
by plowing, cultivating, etc


Often involves a disc or chisel plow rather than a traditional moldboard plow


No
-
till planting is accomplished by drilling seeds into the ground directly
through mulch and ground cover


Soil

Cover

and

Soil

Erosion

Cropping System

Average Annual Soil Loss
(Tons/Hectare)

Percent Rainfall Runoff

Bare soil (no crop)

41.0

30

Continuous corn

19.7

29

Rotation: corn, wheat, clover

2.7

23

Continuous bluegrass

0.3

12

Low
-
input agriculture can
be good for farmers and
their farms


Some farmers are going back to a more natural,
agroecological

farming style


Antibiotics are used only to fight diseases


Low
-
input farms typically don't turn out the
quantity of meat or milk that their intensive
agriculture neighbors do, but their production
costs are lower, and they get higher prices for
their crops


THE END!

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