ES 137 Ch. 10 Presentation

Chapter 10
Henry Dhonau, Josh Becker, Kristen Eiswerth,
Kristin Benusa
● Agriculture has drastically changed the
Brazilian Cerrado (opening case study)
o Humans have been farming for a long time
o Landscapes vary in sustainability
● A renewable and nonrenewable resource
● A very complex substance
● Many different varieties
Soil Fertility
● Many different organisms help to fertilize soil
● Health depends on environmental factors as
Soil Layers
Using and Losing Soil
● Earth’s land area - how much for farming?
● Arable land
● Many different causes of soil and land loss
Effects of Erosion
● Desertification
● Mississippi Dead Zone
Water and Irrigation
● Agriculture accounts for the largest share of
global water use
● How much of fresh water do you think is
used for irrigation (%) ?
● How much cropland (%) do you think is
irrigated worldwide?
Water and Irrigation
● Efficiency (20% - 95%)
● Over-irrigation
● Minnesota Department of Agriculture focus
-The Clean Water Fund
● Nitrogen, potassium, phosphorus, calcium,
magnesium, and sulfur
● N, K, P (limiting nutrients) -- fertilizer
● 20 kg av. (1950)
to 91 kg av.(1990)
● Increased crop yields
● Environmental issues
● Runoff (eutrophication)
● Minnesota Department of Agriculture
monitoring, training, fees,
soil and water quality testing,
nitrogen fertilizer
recommendations and
regulations [how, when, where,
how much to apply (
Alternatives to synthetic fertilizers
● manure
● green manure
-crops grown with the purpose of adding
nutrients to the soil (nitrogen-fixing bacteria
on legumes)
● crop rotation
● organic farming at STOGROW, local farms
(Spring Wind Farm, Open Hands Farm)
● use less fertilizer: Europe vs. North America
conventional farming is energy intensive
reliance on fossil fuels with machinery
nitrogen fertilizer made from natural gas
food processing and transportation
this energy can add up to being much more
than the energy the food actually provides us
● MN Dept. of Ag. -- promotes biodiesel,
= a chemical that kills pests
- biocides ⇢ wide variety of living things
- herbicides ⇢ plants
- insecticides ⇢ insects
- fungicides ⇢ fungi
Other Pest Controls
- salt
- sulfur
- mercury
- arsenic
- spices
- certain plants
- fermented alcohols
- predatory ants
- acids
- oil sprays
- ash
- lime
Benefits vs. Problems
Fun Facts
According to the EPA, total pesticide use per year in the
US amounts to about...
5.3 billion lbs.
Wood preservatives
15.1%Specialty biocides
Source: EPA 2000
3/4 of all American homes
use some sort of pesticide.
Types of Pesticides
organic (!)
toxic metals & halogens
...Roundup Ready…
fumingants = gas for fungus
natural organic pesticides = extracted from plants
inorganic pesticides = use compounds of toxic materials
microbial agents & biological controls = living organisms
or toxins from them
Another Fun Fact
The United Farm Workers of America claims
that 300,000 farmworkers in the US alone
suffer from pesticide-related illnesses every
year. Worldwide, the WHO estimates that 25
million people suffer from pesticide poisoning,
and 200,000 die each year from improper use
of storage of pesticides.
Negative Effects
- exposure to nontarget organisms
- pest resurgence = rebound of resistant pop.
- pesticide treadmill
- some pesticides don’t break down easily
For example...
- Canadian researchers found the levels of
organochlorines in the breast milk of Inuit
mothers in remote arctic villages compared
to women from Canada’s industrial to be 5
times higher.
- Canada’s beluga whales suffer from
pesticide-related illnesses, and their
carcasses have to be treated as toxic waste.
So Many Fun Facts
12 banned pesticides in other countries, but not
in the US, made their way back (after we shipped
them out to countries with lax regulations) to us
in bananas and other crops. Only 8 of them
were banned after the fact. Unfortunately, other
compounds just as toxic as the banned ones are
replacing them.
Health Effects
poisoning & illnesses
birth defects
neurological problems
blurred vision
nausea & headaches
stillbirths & miscarriages
12 Most Contaminated Foods
1. Strawberries
2. Bell peppers
3. Spinach
4. Cherries (US)
5. Peaches
6. Cantaloupe (Mexican)
7. Celery
8. Apples
9. Apricots
10. Green beans
11. Grapes (Chilean)
12. Cucumbers
Organic and Sustainable Agr.
What’s your food’s story?
Lack of harmful chemicals
Local farming
Substitutes for common pesticides
Purely organic vegetables and meats
Organsmic Foods
The rules
No hormones
No antibiotics
No pesticides
No synthetic fertilizers
No genetically modified crops
Animals must be raised on organic feed
no steroids
antibiotics only for sickness
Happy farmer
Happy animals
Happy stomach
Benefits and drawbacks of Organic
● Lower energy costs
● More expensive
● Less erosion
● More difficult to start
● Proven to provide more cancer
fighting foods
● Takes a while to get certified
● crop rotation reduces pests
● Local organic farms
Does anybody here pay attention to
organic vs. inorganic foods?
Brain twister:
What if anti GMO arguments are being
made by organic food industries??
How to farmify and preserve yo land
- Crop rotation to reduce pests
- IPMs (integrated pest management)
- An alternative to pesticides
- Introducing pests to eliminate other
- Plants to eliminate pests
Did you know that!?: In Costa Rica the use of
IPMs removed pesticides entirely from banana
plantations in one region.
Farming methods
Contour planting
o Plowing across a hill instead of up and down
Strip farming
o Different crops in strips, Terracing- different levels of land
Perennial species
o Plants that grow more than two years (To keep soil in place)
Cover crops
o To preserve the soil and its nutrients
o Protective soil cover
Reduced tillage systems
o Less tillage equals more organisms left on the soil to provide nutrients
How does Minnesota farm?
For your viewing pleasure
Contour Farming
Minnesota Department of Agriculture Promoting the change to No-till, Ridge-till, and Mulch-till. All
conservation tillage practices.
Local farms
Community Supported Agriculture
Spring Wind Farm
- Locavore
A person who eats locally
- Economic Threshold
Potential economic damage justifies
Pros and Cons of CSAs?
Why are there not more CSA farms around?