Transcript Chapter 15 Land and Agriculture

Chapter 15 Topics
• 15.1
– Nutrition and malnutrition
– Food Production
– The Green Revolution
• 15.2
– Traditional vs Modern agriculture
– Sustainability - Soil conservation
& pesticide use
– Genetic engineering
• 15.3
– Aquaculture
– Livestock
15.1 Feeding the WORLD
• By 2050 farmers must feed ~9 billion people…50% more than
are fed today!
– Famine: widespread starvation b/c of shortage of food; often
related to prolonged drought
• Nutrition: energy from food
– Calories= 1 kilocalorie (1,ooo calories)
How does the NA diet compare
with the African diet?
– Malnutrition: not enough calories are consumed and/or
insufficient variety to meet the body’s needs; usually related to:
– Poverty & Income: Africa, Asia, S.America (less than $1 a day)
ex: only eating corn or rice
– GOAL: abolish poverty and famine
Sources of Nutrition
• Diet: type and amount of
food eaten
– Balanced- protein {amino acids},
fats, carbs , minerals, vitamins
Food Efficiency
• A measure of the quantity of food (yield)
produced in a given area of land with limited
inputs of energy and resources
– Efficiency - Produce the highest yield (amount of
food) with the least negative impact
– More energy, water and land are used to produce a
Calorie from animals than from plants
•Remember the energy pyramid (10% law)
– Meat often provides more nutrients/gram…however,
not 10 times more!
What are the hidden impacts/costs of growing food?
World Grain Production, 1950-2005
We are producing more grain than ever but there
is less to go around…why?
The GREEN revolution
• New varieties with higher yields
– Mexico 1950-1970 (wheat 8-fold) & India (rice doubled)
– Subsistence farmers – those who grow what
they need with just a bit more to sell:
•Need $ for chemicals and water for new varieties
•Machinery – not useful on tiny farms
•Therefore often remain in or close to poverty
Agricultural Subsidy
• Paid to farmers and agribusiness to supplement income,
manage supply of commodities, influence cost and
supply of commodities
– Corn, wheat, grain, oats, barley, cotton, milk, rice, peanuts,
sugar, tobacco, oilseeds, soybeans
– “From 1995-2009 the largest and wealthiest top 10 percent of farm program
recipients received 74 percent of all farm subsidies with an average total
payment over 15 years of $445,127 per recipient
– hardly a safety net for small struggling
farmers. The bottom 80 percent of farmers
received an average total payment of
just $8,682 per recipient.”
-http://farm.ewg.org/summary.php
Led to industrialization of food…FOOD, Inc.
Why are the bad foods so cheap?
Section 15.2 – Crops and Soil
How do you grow stuff?
Steps
Plow/dig – to mix
nutrients
Fertilize
Water
Control pests and
weeds
Harvest
Past
Farmer, animal,
hand tools
Organic – manure,
compost
Flows through
fields in ditches
Present
Machinery with
fossil fuels
Synthetics with
fossil fuels
Overhead
sprinklers or drip
By hand, hoe, and Chemicals
natural predators
Farmers
Machinery with
fossil fuels
How can we balance efficiency with stewardship?
Past to Present
• Agriculture has changed dramatically, especially since the
end of World War II.
– new technologies, mechanization, increased chemical use,
specialization and government policies that favored maximizing
production.
– allowed fewer farmers with reduced labor demands to produce
the majority of the food and fiber in the U.S. at lower cost
• Although these changes have had many positive effects
and reduced many risks in farming, there have also been
significant costs:
–topsoil depletion,
–groundwater contamination from
fertilizer
–genetic engineering and loss of species
variety
–Chemicals, chemicals, chemicals – you are
what you eat!
–the decline of family farms,
–increasing costs of production,
–neglect of living and working conditions
for farm laborers,
–disintegration of economic and social
conditions in rural communities.
SOIL
• Fertile Soil – supports healthy
plants
– Topsoil – contains the most organic
matter
– More rock the deeper you go
• Soil Conservation –reducing
erosion
–
–
–
–
Terracing -levels
Contour plowing – follow land shape
No-till farming – new crops with old
Composting – enriches soil by
adding organic matter: manure,
grass clippings, fruit and vegetable
scraps
• Salinization – naturally salty soil
creates salty irrigation water
where rainfall is low; big problem
in southern CA
Sustainable Farming
• How do we achieve sustainability?
– Goals—
• environmental health - soil, water, energy
• economic profitability – for farm owners and laborers
• social and economic equity – poverty, animal care and stewardship:
maintaining or enhancing vital resources for future generations
– Agriculture• crop variety avoids soil depletion,
• Biological pest and weed control,
• Sustainable use of water
– Livestock• Selection, nutrition, health, grazing, confinement issues
Demand drives supply…what choices can you make with your food $$$?
What About Pests? – any
No, organism
not like your
thatlittle
grows
brother!
where
you don’t want it and causes economic damage
• Pests destroy a lot of crops…13% in US and 33% worldwide!
Slugs
Stink Bugs
Aphids
Cabbage Looper Moth Caterpillar
What About Pests? – any organism that grows where
you don’t want it and causes economic damage
Wild plants have:
•Variety
•Natural enemies
•Evolved defenses
Pesticides:
•Harmful to beneficial
plants and insects and
people, too!
•Pests develop
resistance
•Pollute water and soil
•Bioaccumulation
Pesticide Industry Ramps Up Lobbying in Bid to Pare EPA Rules
February 24, 2011
By ANNE C. MULKERN of Greenwire
The pesticide industry is applying extra doses of lobbying in an
effort to eradicate federal requirements it considers harmful.
CropLife America - the trade group for Dow
Chemical Co., DuPont, Monsanto Co. and other pesticide
makers - aims to influence dozens of measures, from safe
food and drinking water rules to toxic chemical regulations and
antiterrorism laws. The organization in the last three months of
2010 significantly ramped up persuasion efforts. CropLife
America in that period spent nearly $751,000 on lobbying, a 58
percent increase from a year earlier.
"In the first two years of the Obama
administration… they were going to push for more
precautionary oversight of chemicals."
Environmentalists said CropLife America is
moving to eliminate regulations that are needed to protect
human health and wildlife and could have more success with
the current Congress.
"They seem to have quite a bit of influence with
EPA," Miller said. "The EPA has been really careful to not do
anything that would really step on the toes of the pesticide
industry."
Genetic Engineering – changing DNA in one organism by
combining it with genes from another
Ex: genes from bacteria able
to resist an insect
Arguments for GMOs:
•Increases yield
•Just like crossbreeding but
more efficient
•Desirable traits – resistance,
add. nutrients, fresher longer
Concerns:
•Foods are not labeled
•Not fully tested
•Can invade wild species
•Mixing plant/animal genes
corn
15.3 – Aquaculture and Livestock
Domesticated Animals – animals
bred and managed for human use
Food From Water
Overharvesting resulted in
depletion of fish stocks
Aquaculture – raising fish or
shellfish on farms in water or
ranches (temporary); circulated
water brings O2 in, waste out
Issues: excessive waste
degrades water and wetlands;
disease
North Atlantic Cod
Livestock – animals raised on a
farm or ranch to be sold for profit
What concerns should we
have if this trend continues?
Livestock is important even in
cultures where they aren’t part
of the diet:
•Milk
•Dung for fuel
•Fertilizer
•Work
List 5 issues with livestock as food from Food Inc.