Soil, agriculture, and the future of food by Kiersten Lippmann

Soil, Agriculture, and the
Future of Food
Environmental Science,
Spring 2017

Aldo Leopold
“There are two spiritual
dangers to not owning a
farm. One is the danger of
supposing that breakfast
comes from the grocery,
and the other that heat
comes from a furnace.”
Kiersten Lippmann, 2017

Local, sustainable
agriculture in
MWV
• Farmers markets in Tamworth,
Conway, Ossipee
• Brownsfield market
• Sherman’s Farm Dairy
• Maple syrup houses
• Local breweries
• Apple orchards
• Blueberries/strawberries
• Many options and growing
• “Eat Local”

The Race to Feed the World
• Population will swell to 9-10 billion by 2050
• Feeding 2 billion more people while
protecting soil, water, and ecosystems will
require large scale changes to more
sustainable farming
• Food Security- guarantee of adequate, safe,
nutritious and reliable food to all people at
all times.
• Huge challenge!
• Our ability to produce food has grown
faster (so far) than the global population
• Primary reason behind human population
growth

Undernutrition, overnutrition,
and malnutrition
• Despite rising food production, about 870 million
people suffer from undernutrition
• Receiving fewer calories than the minimum dietary
energy requirement
• Every 5 seconds, a child dies because he didn’t get
enough to eat
• Due to poverty, political obstacles, conflict, and
inefficiencies in distribution
• Energy choices like biofuels affect food supply
• Number and percentage of undernourished people
has been falling since 1960
• Drop in food prices
• People in poor nations might spend 70% on food,
while rich nations spend 10- 15% on food
• Food prices have been rising since 2002.

Overnutrition
• Although 1.1 billion people lack access to
nutritious food, many consume too much
• Overnutrition causes unhealthy weight
gain
• Cardiovascular disease, diabetes, other
health problems
• USA- 1 in 3 adults are overweight
• 500 million obese
• Growing availability of highly processed
foods which are often calorie-rich,
nutrient poor, and affordable (Twinkies,
pizza, chips, sodas).
• Michael Klump (continuing with the
Office theme).

How much food does one
person eat in a year?
• Americans eat about one-ton of food per year (2,000 lbs)
• 31 lbs of cheese, sweets, and lot of starchy foods like
potatoes and grains
• 141 lbs of sweeteners (sugar) per year

The sneaky psychology of
supermarkets
• Music calms you
• Enter at the bakery and produce sections- which makes you
think the store is clean, fresh, welcoming
• Dairy is as far away from the entrance as possible, so you
have to walk by lots of enticements to get there.
• No windows, no clocks, make you lose track of time
• Most expensive items are at eye level, you have to search for
generics.
• Commonly sought after items are mid-aisle, so you can’t just
rush in and out but have to walk by lots of enticing foods
• Most creepy- the eyes of the cartoon characters on cereal
boxes are designed to make eye contact with children… ugh!

Creepy Cereal boxes

So that is something
you know now…
• Sugar is now considered worse for you than
saturated fats, and the single greatest cause
of obesity and obesity related diseases.
• So beware Cap’n Crunch and Tony the Tiger

Malnutrition
• Quality of food is also important
• Malnutrition is a shortage of nutrients the body needs, and occurs when a person
fails to obtain a complete complement of proteins, essential lipids, vitamins, and
minerals
• Can lead to disease
• Kwashiorkor occurs when people eat lots of starch but deficient protein
• Often affects children who recently stopped breast feeding
• Kwashiorkor causes bloating of the abdomen, immune suppression, developmental
delays, and stunted growth
• Protein deficiency and lack of calories can cause marasmus, which causes wasting
or shriveling among millions of children in developing world
• Dietary deficiencies also prevalent
• iron deficiency and anemia
• iodine deficiency and swelling of the thyroid and brain damage
• Vitamin A deficiency and blindness

Melinda Gates Foundation- link between birth
control, overpopulation, and starvation
• The average global fertility rate is 4.17!
• Rwanda, Yemen, and Libya have some of
the highest rates
• US and UK are at around 1.8
• Women in Africa say they are most
concerned about getting pregnant, will
walk 100s of miles for contraceptives
• Can not use condoms, indicates they may
have AIDS- men must comply
• Ties in to childhood starvation and
incidences of nutrition illness
• Big part of reducing world hunger is
reducing birth rates for women in areas
most affected
OUR GOAL:
• to bring access to high-quality contraceptive
information, services, and supplies to an
additional 120 million women and girls in the
poorest countries by 2020 without coercion or
discrimination, with the longer-term goal of
universal access to voluntary family planning

Americans eat
the most
calories per day
• Average
• Most people need at least 2,000
calories a day to function- average
around 2500 depending on age,
gender, activity level, genetics.

Changing face of
agriculture
• To enhance global food security, we need to
examine how we produce foods
• Agriculture- practice of raising crops, and
livestock for human use and consumption
• Most of food and fiber comes from
cropland- land used to raise plants for
human use
• Rangeland- land used for grazing livestock
• Amounts of land used for food production
have increased with human pop. Growth
• 38% of Earth’s surface devoted to
agriculture, uses more land area than any
human activity
• 26% rangeland
• 12% cropland

Industrial Agriculture is a recent human
invention
• For most of human species 200,000 years
existence, we were hunter-gatherers
• About 10,000 years ago, as glaciers
retreated, climate warmed, some people
began to raise plants from seed and
domesticate animals
• For thousands of years, ag work was human
and animal muscle powered- Traditional
Agriculture
• Planted polycultures (many types) of
different crops on small plot of farmland
• Still practiced today in many areas

Industrial agriculture
• Industrial revolution introduced large-scale
mechanization and fossil fuel combustion to
agriculture
• Farmers replaced horses and oxen with
tractors that were faster and more powerful
• Industrial Agriculture- boosed yields by
intensifying irrigation, synthetic fertilizers.
• Industrial Ag.now on 25% world’s cropland
• Use of machinery lead to monocultures-
which reduces biodiversity
• In monoculture all plants are genetically
similar, and equally susceptible to bacterial
and viral diseases.

Industrial Agriculture
• Reliance on genetically similar crops leads to
concerns over crop failure
• Conserve wild relatives of crop plants and crop
varieties which contain genes we may need to
reintroduce to commercial crops
• Seeds banks- store 1- 2 million different seed
types
• Preserve the natural gene combinations of plants
well adapted to their environment
• Monocultures narrow the human diet
• 90% of food we eat comes from 15 crop species
and 8 livestock species
• Only 30% of maize varieties in Mexico from the
• In US the varieties of some fruits and vegetables
have decreased by 90%

The Green Revolution boosted
production- and exported
industrial agriculture
• Desire for greater quantity and quality of food
• Green Revolution- new technology, crop varieties, and farming
practices introduced to developing world
• Drastically increased food production in these nations
• Began in 1940s
• Norman Borlaug- American agricultural scientist introduced a
specially bred type of wheat to Mexico with large seed heads, disease
resistance, high yields
• Success inspired similar projects in India, Pakistan…
• Soon developing countries were doubling, tripling yields of wheat,
rice, corn, other crops
• Millions avoided starvation
• Borlaug celebrated as having saved more lives than anyone in history

Mixed Effects of Industrial
Agriculture
• Allowed food production to keep pace with growing population
• Many adverse environmental and social impacts
• Between 1961 and 2010, food production more than tripled, and
per-person food production rose 48%, while amount of land
converted for ag. increased by just 10%
• Negatives- intensive application of water, fossil fuels, pesticides,
inorganic fertilizers worsened pollution, top soil losses, and soil
quality.
• Far more energy intensive
• Displaces low-income farmers
• Migration of poor and rural people to cities

Sustainable Agriculture Reduces
Environmental Impacts
• Industrial ag. has allowed food production
to grow but has many negative effects
• New land suitable for farming is running
out
• Sustainable Agriculture- maintains
healthy soil, clean water, and genetic
diversity for long-term crop and livestock
production
• Maintains high yields into the future
• Treats ag. Systems as ecosystems
• Reduces use of fossil fuels
• Low input ag. uses lesser amounts of fuel,
energy, water, pesticides, antibiotics, and
growth hormones than industrial ag.

Soils- not just dirt
• Complex system of disintegrated
rock, organic matter, water, gases,
nutrients and microorganisms
• Vital for ag. , forests and
functioning of Earth’s natural
systems
• Composition of soil can have as
much influence on ecosystems as
do climate, latitude and elevation

Soil forms slowly
• Forms over geologic time
• Parent material- base geological material at a location
• Ash, lava, glacial deposits of rock or sediment
• Bedrock- continuous mass of solid rock that makes up Earth’s crust
• Weathering- physical, chemical, biological processes that convert large
rock particles to smaller particles
• Once weathering produces fine particles, biological activity contributes
to soil formation through decomposition, deposition, and
accumulation of organic matter
• Eg. Leaf litter in a forest
• Humus- dark, spongy, crumbly mass of material made up of complex
organic compounds
• Soils with high humus content hold moisture well and are productive
for plant life
• Forming just 1 inch of soil can require hundreds or thousands of years,
so we need to conserve what we have
• Forms so slowly that we cannon regain fertile soil once it is lost.
Hummus

Soil profiles consist of layers (horizons)
• As wind, water, and organisms move and sort
the fine particles weathering creates, distinct
layers develop
• Each layer is a horizon
• Entire cross section from soil to bedrock is a
soil profile
• Degree of weathering and concentration of
organic matter decrease down the soil profie
• Minerals are transported down due to
leaching, where solid particles suspended in
liquid are transported to another location
• Topsoil- crucial horizon for agriculture and
ecosystems “A horizon”
• Over time unsustainable agriculture will
deplete organic matter, reducing soil fertility
and ability to hold water

Regional differences in soil traits affect
agriculture
• Soils vary with location and are greatly affected by
climate and other variables
• Tropical rainforest – heavy rainfall quickly leaches
minerals and nutrients out of the topsoil and E
horizon
• Warm temps speed up decomp so only small
amounts of humus remain in the thin topsoil
• In US Midwest, less rainfall and less leaching keeps
nutrients within reach of plants’ roots.
• Thick, rich topsoil of the prairies
• Low nutrient content in tropical soils- swidden
agriculture- where a farmer clears a plot of forest,
cultivates for 1-2 years, then clears another plot
after soil is no longer fertile (slash and burn).
• Many cleared plots never grow back to forest and
are used for grazing livestock

Maintaining Healthy Soils
• Over time soils have deteriorated in quality
and declined in productivity
• Soil Degradation
• Each year we gain 85 million people yet lose
12-17 million acres- size of W. Virginia) of
productive cropland to degradation
• Soil erosion, nutrient depletion, water
scarcity, salinization, waterlogging, chemical
pollution, changes in soil production and pH,
loss of organic matter from soil.
• Reduced potential rates of global grain
production on cropland by 13%
• Dangerous trend as we need to soon feed 2
billion additional people (by 2050)

Erosion can degrade soil ecosystems
• Erosion- transport of material from one place
to another by action of wind or water
• Deposition- when eroded material is
deposited at a new location
• Natural processes that help create soil
• Flowing water across a river delta deposits
rich soils (loam)
• Erosion is a problem when it occurs more
quickly than soil is formed
• Thins topsoil
• Overcultivating fields, excessive tilling,
overgrazing, and clearing forests on steep
slopes make land more vulnerable to erosion

Soil erosion is a global problem
• Humans have accelerated erosion
rates
• Human activities move over 10
times more soil than all other
natural processes combined
• More than 19 billion ha of world
croplands suffer
erosion/degradation
• Farmlands in US lose 5 metric tons
of soil for every ton of grain
harvested
• Sustainable farming slows erosion
rates vs. industrial farming

Desertification reduces productivity of arid
lands
• Much of the world lives and
farms drylands, arid and semi
arid, cover 40% of Earth
• Prone to desertification- where
more than 10% of productivity is
lost as a result of erosion, soil
compaction, forest removal,
overgrazing, drought,
salinization, climate change, etc.
• Wind and water erosion
• Endangers food supply of 1
billion people
• Costs tens of billions of $$

The Dust Bowl prompted US to fight erosion
• Prior to cultivation, on Great Plains, native prairie grasses held soils in
place
• In late 19th, early 20th centuries, settlers arrived in Oklahoma, Kansas,
Texas, New Mexico and Colorado, to farm
• Grew abundant wheat, and grazed cattle, leading to erosion and altering
soil structure
• In 1930s, a drought exacerbated human impacts- strong winds began to
erode millions of tons of topsoil
• Dust storms traveled up to 1250 miles, blackening train and snow as far
as NY and DC.
• Some areas lost 4 inches of topsoil in a few years
• Most affected region in Great Plains is known as “Dust Bowl”
• Forced thousands of farmers off their lands
• US Congress passed the Soil Conservation Act of 1935 in response
• Work with farmers to develop conservation plans for individual farms
• Model for other nations where farmers fight erosion

Sustainable Agriculture begins with soil
management
• Farming techniques can reduce
impacts of conventional
cultivation on soils and combat
soil degradation
• Some are very old techniques

Crop Rotation
• Farmers alternate the type of
crop grown in a field from one
season or year to the next
• Returns nutrients to soil
• Break cycles of disease
• Minimize erosion
• US farmers rotate between
wheat or corn and soybeans
• Reduces insect pests
• Plant cover crops

Terracing and Intercropping
• On steep terrain, terracing is an
effective method to prevent erosion
• Terraces are level platforms cut into
hillsides
• Transforms slopes into a series of
staircases
• Intercropping- plant different crops in
alternating bands
• Slows erosion by providing more
ground cover than single crop
• Reduces disease, insect, and
replenishes soils when legumes are
planted

Shelterbelts or windbreaks
• Rows of trees or tall plants along
edge of fields slow the wind
• Can be combined with
intercropping
• Trees also provide fruit, wood,
and wildlife habitat

Conservation Tillage
• Approaches that reduce the amount of tilling relative to conventional farming
• No-till farming- rather than plowing the field after harvest, farmers leave crop residues atop their fields, keeping the soil covered with plant material at all
times. To plant the next crop, they cut a thin, shallow groove in the soil and drop in seeds, covering them with a “no-till drill”.
• Increases organic matter and soil biota, while reducing erosion
• Improves soil quality
• Combats climate change by storing carbon in soils
• In US, ¼ farmland no-till
• 40% conservation tillage

Conservation Tillage and No-till Farming
• Methods are also catching on in
subtropical S. America
• Brazil, Argentina, Paraguay, over
half cropland is no-till
• Especially important in these areas
because heavy rainfall promotes
erosion of tilled soils
• Crop yields increased
• Erosion reduced
• Soil quality enhanced
• Pollution declined
• Costs to farmers dropped 50%

Costs and Benefits of no-till farming
• Critics claim no-till requires more
chemical herbicides because weeds are
not removed prior to planting
• No-till also requires synthetic fertilizers
because non-crop plants take up some
nutrients
• True in many industrialized nations
• In developing nations, farmers rely on
green manures- dead plants as fertilizers-
and rotate cover crops including nitrogen-
fixing legumes
• Allows less use of fertilizers or herbicides
because cover crops reduce weeds and
legumes and manures nourish the soil.
• Applicable to smaller scale agriculture
Video- No till farming

Grazing can contribute to soil
degradation
• Raising livestock impacts soil
• Humans keep 3 billion sheep, cattle, goats that
graze on the open range
• If livestock do not exceed the range’s carrying
capacity, grazing may be sustainable
• Grass can regrow
• Overgrazing happens when there is no
regeneration of plant biomass

Grazing and soil degradation
• Cattle also churn up soil and cause
erosion
• This is a positive feedback cycle-
where erosion makes it difficult for
vegetation to regrow, promoting
further lack of cover and more
erosion
• Promotes growth of non-native
vegetation
• Compacts soils and alters their
structure
• Further decreases plant growth
and survival

Grazing and soil degradation
• Millions of acres of Federal US
lands are open to private cattle
grazing
• Video: Bundy “take-over” of
Federal wildlife refuge
• 70% of world’s cropland are
considered degraded by cattle
• Greatest cause of desertification
• Lost productivity on degraded
lands costs $23 billion a year

Agricultural Subsidies Affect Soil Degradation
• Nations spend billions of dollars on
government subsidies to support
agriculture
• Roughly 1/5 of the income of average
farmer comes from subsidies
• Help compensate farmers for bad years
• But -encourage people to cultivate land
that would otherwise not be farmed
• Produce more food than needed, driving
down prices
• Practice unsustainable farming methods
• Some suggest a better approach is for
farmers to buy insurance

US and international programs support soil
conservation
• WWF, other NGOs
• US Congress passes farm bills with
provisions requiring farmers to adopt
soil conservation practices before
receiving government subsidies
• Conservation Reserve Program (1985)
• Pays farmers to stop cultivating highly
erodible cropland, and instead place
in conservation reserves
• Reserves now cover an area the size
of Iowa
• UN promotes soil conservation
through a variety of programs by Food
and Ag. Organization (FAO)

Watering and Fertilizing Crops
• Irrigation boost productivity but can damage soil
• Plants require water for optimal growth
• Irrigation- artificial provision of water to support agriculture
• Maintain high yields through drought
• Turn unproductive, dry regions to farmlands
• 70% of water withdrawn by people goes to crops worldwide
• May deplete aquifers and dry up lakes
• Excessive irrigation may degrade soils
• Waterlogging- when over-irrigation drowns roots, suffocating
plants
• Salinization- build up of salts in surface soil layers
• Common in dry areas with minimal rainfall, where irrigation,
then evaporation pulls salts up from lower soil horizons
• Salinization reduces productivity on 1/5 of irrigated
croplands, costs $11 billion a year

Sustainable Approaches to Irrigation
Maximize Efficiency
• Better match crops to climate
• Subsidies encourage farmers to
grow water intensive crops in dry
areas (water and cotton)
• Wastes lots of water, bean or
wheat would be better choices
• Improve irrigation efficiency
• Currently plants use just 40% of
irrigation water
• Drip irrigation increase efficiencies
to 90%

Fertilizers boost crop yields but can be over
applied
• Plants require nitrogen, phosphorus and potassium to grow, along with other
nutrients
• Leaching and plants remove these from the soil, reducing crop yields over time
• Fertilizer- substances that contain essential nutrients for plant growth
• Inorganic fertilizers- mined or synthetically made nutrient supplements
• Organic fertilizers- remains or wastes of organisms (manure, crop residiues,
fresh vegetation- green manure, compost
• Inorganic fertilizer use during Green Revolution enhanced crop yields and
global food production
• Caused increasingly severe pollution problems
• Leaching, contaminates ground water
• Nitrogen and phosphorus run-off spurs algal blooms in Chesapeake Bay, killing
animal and plant life
• Also affects many ponds and rivers
• Nitrogen air pollution causes acid rain, and photochemical smog

Chesapeake Bay Dead Zone- Video

Sustainable Fertilizer Use involved monitoring
and targeting nutrients
• Target delivery to plant roots to
avoid overapplication of fertilizer
• Can be added to drip irrigation
systems
• No-till and conservation can inject
fertilizer with seeds
• Farmers monitor soil nutrients,
fertilize only when low
• Organic fertilizers more sustainable
because they add material to the
soil

Controlling pests, preserving pollinators
• Pest- any organism that damages
crops we value
• Weed- any plant that competes
with crops
• Insects, fungi, viruses, rodents,
weeds that eat, infect, or
compete with crop plants

We have developed thousands of chemical
pesticides
• Insecticides- kill insects
• Herbicides- kill plants
• Rodenticides-kill rodents
• Fungicides- kill fungi
• All above are pesticides
• Necessary because the modified ecosystems of
farms, limit natural mechanisms to control pests.
• 900 million lbs of pesticides used in US a year
• ¾ on agricultural lands
• Since 1960, use has increased 4X
• Leveled off in developed nations, rising in
developing world
• Exposure can have health consequences on people
and other organisms

The DDT Saga- Video

Pests Evolve Resistance Pesticides
• Despite their toxicity, pesticides tend to decline in
effectiveness with time
• Pests evolve natural resistance
• A small fraction of the many many individuals in a
population of weeds, insects, microbes are
naturally genetically resistant to a pesticide
• Over time, those pests with resistant genes
become more prevalent
• Pesticides cease to be effective
• “Pesticide Treadmill” arms race between pests and
chemists
• Currently, there are 9,000 cases of resistance
among insects
• Many have evolved resistance to multiple
chemicals

Process of Pesticide Resistance

Biological Control pits one organism against
another
• Because of the problems with
pesticides (health risks, resistance,
toxicity) pests are often battled with
organisms that eat or infect them
• Biological control/biocontrol is more
sustainable
• Example- parasitoid wasps are natural
enemies of many caterpillars. Lay eggs
on caterpillar, infect them, larvae eat
the caterpillar killing it
• Reduces pesticide use
• Cactus moth controlled invasive
cactus in Australia

Problems with biological
controls- cane toad,
• The cactus moth has spread to Florida,
killing native and rare Cacti
• Could devastate cacti in southwest US
• Cane Toads- video
• Introduced to control insect pests-
took over. Poisonous to animals, took
over.

Bigger Picture – bats, white-nose syndrome,
and pest control
• Video- white nose
• By eating insects, bats save farmers
$53 in pesticide costs a year
• Bats eat about 1,200 insects per
hour!
• In many caves in New England
many species are dying at rates of
80 to 90 %
• Bats are not related to rodents,
more closely related to primates
• Live up to 40 years, have one to
two pups a year, do not thrive in
captivity

Integrated pest management combines varied
approaches to pest control
• Combine the best chemical and
biocontrol approaches
• Integrated Pest Management-
incorporated numerous techniques
• Close monitoring of pest populations
• Biocontrol approaches
• Use of synthetic chemicals when
needed
• Habitat alteration
• Crop rogation, transgenic crops,
alternative tillage, mechanical pest
removal

Integrated Pest Management in Indonesia
• Subsidized pesticide use for years
• But pesticides were actually
making pest problems worse
• Killing natural enemies of the
brown planthopper, devastated
rice fields
• Indonesian government banned 57
pesticides and promoted IPM
• In four years, pesticide use
dropped by half, rice yields rose by
13%, and approach has spread
through rice-growing regions of
Asia

Pollinators are beneficial “bugs” worth
preserving
• Some insects are essential to agriculture
• Insects that pollinate crops are vital to
food production
• Pollination- process where male sex cells
of a plant (pollen) fertilize female sex cells
of a plant (plant sex).
• Pollinators- animals that move pollen
from one flower to another
• Plants attract pollinators with flower,
nectar, and sweet smells
• Over 800 types of cultivated plants rely
on bees, wasps, beetles, moths,
butterflies and other insects for
pollination

Decline of bees and colony collapse disorder
• Honeybee in decline due to parasitic mites
• Entire hives inexplicably dying off in mid 2000s
• Die-offs continue, and up to one-third of
honeybees have died off in colony collapse
disorder
• Scientist racing to discover cause
• Hypotheses include pesticide use, new parasite, or
combo of stresses that weaken the bee’s immune
system
• While controlling “bad” bugs we need to be careful
not to control the “good”
• Honeybees pollinate crops that comprise one-third
of US diet, an provide $15 billion in annual services
• Video- colony collapse disorder

Raising Animals for Food
• As wealth and global commerce
increases, so does consumption of meat,
milk, eggs, and other animal products
• Domestic animals raised for food rose
from 7.3 billion in 1961 to over 27 billion
today
• Most are chickens
• Global meat production increased 5X
since 1950
• United Nations FAO, estimates that as
more developing nations go through the
demographic transition, and become
wealthier, total meat consumption will
double by 2050.
Per-person production of meat
from farmed animals and seafood
has risen steadily worldwide

Food choices are energy choices
• What we eat affects how we use
energy and the land that supports
agriculture
• Every time one organism consumes
another, only about 10% of the
energy moves from one tropic level
to the next
• Most is used up in cellular
respiration
• Eating meat is far less energy
efficient than vegetarian
• Greater ecological footprint
Producing different animal food
products requires different
amounts of animal feed

Eating meat and energy consumption
• Some animals convert grain feed
into milk, eggs or meat more
efficiently than others
• Impacts land use, some animals
require more land and water than
others
• Eggs and chicken require least
space and water
• Beef requires the most
• What we choose to eat, is also how
we choose to use resources such as
land and water
Producing different types of
animal products require different
amounts of land and water

How much oil in a hamburger?

Feedlots have benefits and costs
• Feedlots- huge warehouses or pens
designed to deliver energy-rich
food to animals living in extremely
high densities
• Nearly half world’s pork and most
poultry come from feedlots
• Make meat affordable
• Reduces grazing impacts
• 45% of grain production goes to
feeding livestock and poultry
• Elevates prices of staple grains

Feedlot Costs
• Livestock produce huge amounts of manure
and urine, and their waste can pollute water
• Heavy use of antibiotics to control disease
• Antibiotic resistance
• Major source of greenhouse gases, such as
methane, that lead to climate change
• Livestock contributes 14% of greenhouse gas
emissions worldwide
• Meat, eggs, and dairy are “free-range” but
that is a broad definition
• For example in poultry, the only certification
requirement is birds are given access to the
outdoors
• More costly than conventional

We raise seafood with aquaculture
• Most marine fisheries are
overharvested
• Wild fish populations are plummeting
• Fish farms may be the only way to
meat demand
• Aquaculture- cultivation of aquatic
organisms for food
• 220 freshwater and marine species
are cultivated
• Open water in net-pens, or in ponds
and holding tanks
• Has increased 5X in past 20 years

Costs and Benefits of Aquaculture
• Helps reduce fishing pressure on wild stocks
• Consumes fewer fossil fuels, safer work
environment
• Energy efficient- 10X as many fish per unit
area.
• Can produce prodigious amounts of waste
• Fish are fed grain, affects food supplies for
people
• Fed fish meal, placing pressures on wild
populations
• If farmed aquatic organisms escape (eg. Carp),
can outcompete with native species
• Salmon genetically engineered for rapid
growth could spread disease or introduce
genes to wild salmon

Video- fish farming for salmon

Genetically Modified Food
• A type of genetic engineering, where scientist
directly manipulate an organism’s genetic
material in a lab by adding, deleting, or
changing segments of its DNA
• Genetically Modified Organisms (GMOs) are
organisms that have been genetically
engineered using recombinant DNA of
multiple organisms
• Goal is to place genes that code for desirable
traits (rapid growth, disease resistance) into
organisms lacking these traits
• Organism that contains DNA from another
species is called transgenic, and genes moved
between them called transgenes

Genetically Modified Organisms (GMOs)
• The creation of transgenic organisms is one
type of biotechnology, an application of
biological science to create products derived
from organisms
• Helps develop medicines, clean up pollution,
understand cancer, make better beer and
cheese.
• We have always modified organisms with
artificial selection
• But GM organisms are created by mixing DNA
of organisms that are different, like bacteria
and plants, or spiders and goats.
• Selective breeding selects from a combination
of genes that come together naturally-
genetic engineering creates novel
combination directly in a lab
Several Notable GM foods

Biotechnology is transforming the products
around us
• In just three decades, GM foods are now
mainstream agriculture
• Most GM foods are modified to resist
herbicides, so farmers can kill weeds but
not crops
• Resist insect attack
• GM foods are grown on 11% of all
cropland in the world
• In US roughly 90% of corn, soybean,
cotton, and canola are genetically
modified
• Over 70% of processed foods in US
contain GMs
• You eat GMs on a daily basis

Impacts of GM foods
• Advance yields by producing crops with high drought
tolerance for use in arid regions
• Developing high-yield crops to feed growing population
• Most of this has not happened because companies that
develop GM seeds do not profit from selling seeds to small
farmers in developing nations
• Instead, GM seeds are mostly developed for insecticide and
herbicide resistance in developed nations
• GM crops actually increase herbicide use due to evolved
weed resistance
• GM plants can interbreed with wild plants, to distances of at
least 20 miles- ecological impacts as yet unknown
• Many experts feel GMs crops are so new that we should
proceed with caution and use the precautionary principle, to
wait on taking action until the ramifications are understood
In just over a decade, weed
resistance to glyphosate spread
across North America
(www.weed-science.com)

Public Debate Over GM foods continues
• Ethical and economic concerns drive
the public debate
• Tinkering with food seems morally
wrong or dangerous to many
• Global supply is dominated by large
corporations, Monsanto, Bayer
CropScience, Syngenta, Dow..
• These corporations threaten family
farmers- farmers have been required
to pay damages for cultivating
patented GM crops (some by
accident)
• More than 60 nations require labelling
of GM foods, but not the US
Video- Monsanto and GMs

Growth of Sustainable
Agriculture
• Organic agriculture is booming
• Uses no synthetic fertilizers, insecticides,
fungicides or herbicides
• 1990 Congress passed the Organic Food Production
Act to establish national standards for organic
products
• Certified “organic” standards went into effect in
2002
• Benefits for farmers- lower costs, high value
produce, reduced chemical pollution and soil
degradation
• Farmers must use organic practices for three years
before certifying- risk
• Price is a big obstacle- organic foods are 10 to 30%
more expensive than conventional
• Some (milk) can cost twice as much

Organic Foods and Farming
• 3 of 4 Americans buys organic at
least occasionally
• Sales have tripled worldwide
between 2000 and 2013
• Production of organic food is
increasing along with demand
• Organic farming can be at least as
profitable for farmers as
conventional
• Increasing especially rapidly in
developing nations
Sales of organic food rise over
time

Locally supported Agriculture is growing
• Reduces use of fossil fuels in transport
• Average food product sold in a US
supermarket travels 1,000 miles
between farm and grocery
• Produce is often chemically treated to
preserve freshness
• “think global, eat local”
• Farmers’ markets- where consumers
buy meats and fresh fruits and veggies
from local farmers
• Often offer organic, local varieties not
found in supermarkets
Farmers’ markets local to MWV

Locally supported ag.- CSA
• Community supported
agriculture (CSA) where
consumers pay a farmer in
advance for a share of their
yield, usually a weekly delivery
of produce
• Consumers get fresh produce,
farmers get a guaranteed
income stream
CSAs

Sustainable Agriculture provides a roadmap
for the future of food
• Best way to make the agricultural system
sustainable is to mimic natural ecosystem
functions
• Ecosystems are sustainable because they operate
in cycles and are stabilized internally through
negative feedback loops
• Provide a model for agriculture
• Crucial for us as we continue to grow in
population
Ecosystem approach to agriculture

Conclusion
• Over our 10,000 year history with agriculture
methods of food production have changed
substantially
• Intensive agriculture exerts many negative
environmental impacts but have boosted food
supplies and helped reduce land pressure
• To support 9 billion people by 2050 without
degrading soil, water, and pollinators we must
shift to sustainable agriculture
• Biological pest control, organic agriculture,
pollinator conservation, preservation of
native crop diversity, sustainable aquaculture,
and some degree of GM of food
• All part of the game plan for a sustainable
future

Soil, agriculture, and the future of food by Kiersten Lippmann

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