AP Exam

1
AP Exam

• Part III

2
Marine Ecosystems

• Coastal- occur near shore where tides and
  currents are always changing, causing a mixture
  of nutrients.
• Zone is from the high tide mark of shorelines to
  the continental shelf.
• Organisms include coral (in tropical regions),
  zooplankton, phytoplankton, crustaceans,
  echinoderms, dolphins, sharks, etc..

3
Marine Ecosystems

• Esturaries- Animals in these areas must be able
  to adapt to a rapid and constant change in
  salinity.
• Rich in nutrients
• Excellent spawning and breeding grounds for fish,
  crustaceans and birds.

4
Inland Wetlands

• Water levels vary from standing water in the wet
  season to none during the dry season or during
  droughts. Include marshes, swamps and bogs.
• Differentiate between a marsh, swamp and bog

5
Marine Ecosystems

• Open Ocean- These areas occur beyond the
  continental shelf .
• Deep water up to 11,000 meters
• Zones below 200 m are dark, cold, and poor in
  nutrients.

6
Legislation Regarding Aquatic Environments

• Alaska National Interest Lands Conservation Act,
  1980
• Designated certain public lands in Alaska as
  units of the National Park, National Wildlife
  Refuge, Wild and Scenic Rivers, National
  Wilderness Preservation, and National Forest
  Systems, resulting in general expansions of all
  systems.
• Created 79.54 million acres of refuge land in
  Alaska.
• 27.47 million acres were designated as wilderness.

7

• Anadromous Fish Conservation Act, 1965
• Conservation, development and enhancement of
  anadromous fish, including those in the Great
  Lakes
• Anadromous fish are those that are born in fresh
  water, migrate to salt water to grow into adults
  and return to fresh water to spawn.
• Examples salmon, smelt, striped bass, sturgeon
• Catadromous fish- live in fresh water and enter
  salt water to spawn.

8
Additional Legislation

• Convention for the Conservation of Antarctic
  Marine Living Resources (CCAMLR), 1980-
• Management of all southern ocean fisheries.
• Fish Wildlife Act, 1956
• Emphasis on the commercial fishing industry, but
  also adheres to every citizens right to fish for
  pleasure and enjoyment.

9

• Fish and Wildlife Coordination Act, 1980
• Authorized financial and technical assistance to
  the states for the development, revision, and
  implementation of conservation plans and programs
  for non-game fish and wildlife
• Great Lakes Fish and Wildlife Restoration Act,
  1998
• Marine Mammal Protection Act, 1972
• Conservation of marine mammals with management
  vested in the Department of Commerce for
  cetaceans (whales, dolphins, and porpoises) and
  pinnipeds (seals, sea lions, walrus) other than
  the walrus.

10

• A sterile male technique of pest control
• A. relies on the use of phermones, chemicals that
  attract fertile males away from reproductively
  capable females.
• B. Is often effective because females of many
  insect species breed only once during their
  lifetime.
• C. Relies upon genetic engineering techniques to
  produce infertile males.
• D. Uses male animals that are sterilized by
  treatment with Bacillus thuringiensis bacterium.
• E. Can cause eggshell thinning in some bird
  species.

11
Aquatic Review

• A mixture of fresh and saltwater is known as
• A. brackish
• B. Gray water
• C. Black water
• D. Connate water
• E. Lentic water

12
International Acts

• Antarctic Treaty signed Dec. 1, 1959/ enforced
  June 23 1961
• Antarctica is the only continent with no
  nations.  While seven nations (not including the
  United States) have made claims to Antarctica, no
  single nation controls any part of the continent.
  The Antarctic Treaty governs the actions of
  people in Antarctica. 12 nations listed in the
  preamble signed the Antarctic Treaty on 1
  December 1959 at Washington, D.C. The Treaty
  entered into force on 23 June 1961.

13

• Cairo Conference on Population Development-
  Sept. 1994
• The United Nations International Conference on
  Population and Development (ICPD) was held from
  5-13 September 1994 in Cairo, Egypt. During this
  two week period world leaders, high ranking
  officials, representatives of non-governmental
  organizations and United Nations agencies
  gathered to agree on a Programme of Action.
  Main Point- Population Control

14

• Kyoto Conference-1997
• Sponsored by the United Nations
• Held in Kyoto, Japan
• Result
• 1)Agreement among 10 nations requiring greenhouse
  gas emissions reduction, especially carbon
  dioxide, to 5 below 1990 emissions by 2010.
  Developing nations reductions are voluntary.
• 2) Long term objective was to prevent emissions
  from human sources from interfering with the
  natural climate system.

15

• Montreal Protocol- 1987 (Amended in 1990, 92)
  
• Agreement to reduce air pollutants that destroy
  stratospheric ozone. CFCs, halons, carbon
  tetrachloride, and methyl chloroform--are to be
  phased out by 2000 (2005 for methyl chloroform).

16

• Rio Earth Summit- 1992
• Held in Rio de Janeiro, Brazil.
• Attendees worlds leaders, politicians,
  diplomats, etc.
• Result of Summit
• 1)Attempts will be made to reduce greenhouse gas
  emissions by the year 2000 to the 1990 levels
• 2) Developing countries will be given more and
  easier access to technology that minimizes
  environmental damage.

17

• UN Conference on the Human Environment, Stockholm
  (Capital of Sweden)- 1972
• The United Nations Conference on the Human
  Environment, having met at Stockholm from 5 to 16
  June 1972,having considered the need for a common
  outlook and for common principles to inspire and
  guide the peoples of the world in the
  preservation and enhancement of the human
  environment

18

• Cities Treaty- 1976
• Adopted by Congress in 1976, in an effort to
  maintain and protect endangered populations in
  ancestral habitats, prohibits the removal of
  Asian elephants and other endangered species from
  the wild and their importation into the United
  States. The stresses on habitat and space,
  poaching and unregulated hunting have severely
  limited the ability of native populations to
  maintain enough genetic diversity to survive.

19

• Hadley cell model
• Resides over the equator to the subtropics. It
  causes dry are to absorb moisture as it descends
• The major environmental result of creating power
  through nuclear fuel is
• Storing its waste
• Nuclear breeder reactors convert
• Nonfissable U238 into plutonium
• Integrated pest management is the concept that
• All insects can be controlled by using a natural
  biological or other natural controls

20
Pesticides

• Biocide - Kills wide range of organisms.
• Herbicide - Kills plants.
• Insecticide - Kills insects.
• Fungicide - Kills fungi.
• Acaricide - Kills mites, ticks, and spiders.
• Nematicide - Kills nematodes (round worms)
• Rodenticide - Kills rodents.
• Avicide - Kills birds.
• Algicides Kills algae

21

• Chemical Classes
• Inorganic Pesticides - Broad-spectrum, generally
  highly toxic, and essentially indestructible.
  (arsenic - copper)
• Generally neurotoxins
• Natural Organic Pesticides (Botanicals) -
  Generally plant extracts. (nicotene - phenols)
• Fumigants - Small molecules that gasify easily
  and penetrate materials rapidly. (carbon
  tetrachloride - ethylene dibromide)
• Chlorinated Hydrocarbons - Fast acting and highly
  toxic to sensitive organisms. (DDT - mothballs)
• Inhibit nerve membrane ion transport and block
  nerve signal transmission.
• Persistent - Tend to biomagnify.
• Organophosphates - Extremely toxic to mammals,
  birds and fish. (Malathion)

22

• 1939- DDT- dichlorodiphenyltrichloroethane
  created by Mueller. He received a Nobel Prize in
  1948.
• Advantage of DDT Cheap, stable, soluble in oil,
  and easily spread over a large area.
• Highly toxic to insects, but relatively nontoxic
  to mammals.

23
The Ecological Niche

• The role as species plays in an ecosystem
• Habitat the actual physical location where a
  species lives
• N-dimensional hypervolume- many conditions and
  resources influence the maintenance, growth, and
  reproduction of an organism
• Fundamental Niche full potential range of
  conditions and resources it could theoretically
  use if no competition
• Realized Niche part of a fundamental niche an
  organism occupies

24
Generalists vs Specialists

• Generalists
• Have broad niches
• Live in many different places, eat variety of
  foods, wide range of environmental conditions.
• Specialists
• Narrow niches
• One type of habitat, only one or two types of
  food
• More prone to extinction
• Advantage in constant environmental conditions

25
Types of Species

• Native species, exotic/alien species
• Indicator Species species that serve as early
  warnings that a community or ecosystem is being
  damaged (Birds)
• Keystone role in ecosystem is more important
  than abundance, play pivotal roles in structure,
  function, and integrity of ecosystem b/c
  critically linked to large number of other
  species

26
Competition and Predation

• Interspecific competition two or more species
  compete for limited resource, can harm competing
  species
• Predation one species feeds directly on all or
  part of living organisms. Predator benefits, prey
  is harmed
• Symbiosis long-lasting relationships, species
  live in intimate association
• Parasitism parasite feeds on host
• Mutualism both benefit
• Commensalism one benefits, other is neither
  harmed nor helped

27
How do species compete?

• Interspecific competition results when niches
  overlap. One species must
• Migrate to another area
• Shift its feeding habits
• Suffer a sharp population decline
• Become extinct in that area
• Species compete in two ways
• Interference one species limits another's
  access to resource, member establish a territory
• Exploitation competing species have access

28
Principle of Competitive Exclusion

• Two species require the same resource cannot
  coexist indefinitely in ecosystem where there is
  not enough of that resource to meet the needs of
  both species.
• Species have reduced competition by
• Resource partitioning the dividing up of
  available resources
• Character displacement species develop physical
  or behavioral characteristics or adaptations
  allowing them to use diff resources

29
Predator and Prey Interaction

• Predators feed on prey, do not live in or on
  prey. () feedback system for predator limited by
  (-) feedback when prey populations fall below
  certain minimum.
• benefits prey eliminates sick, weak, aged
• Predators increase chances of getting meal
• Pursuit run fast to catch prey, keen eyesight,
  hunt in packs
• Ambush camouflage
• Prey defend themselves against predators by
• Run, swim, fly fast, keen sight or sense of smell
• Chemical warfare chemicals that are poisonous
• Warning coloration predators know animal is bad
  tasting
• Mimicry species take on appearcnce of poisonous
  animal

30
Symbiotic species Interactions

• Parasitism
• Parasitoids parasites that kill hosts as part
  of life cycle (used by farmers for pests)
• Endoparasites live inside host
• Ectoparasites live outside host
• Mutualism
• Nutritional Mutualism lichens photosynthetic
  algae and chlorophyll- lacking fungi. They
  cannot live apart, aka obligatory mutualism.
• More common when resources are scarce
• Commensalism
• Redwood sorrel benefits from growing in the shade
  of tall redwood trees

31
Ecosystem Structure

• Physical appearance
• Niche structure
• Species diversity
• Species abundance

32
An ecosystems respond to change

• Ecological succession gradual change in species
  composition of given area.
• Primary gradual establishment of biotic
  communities (lifeless, soil-less area)
• Pioneer species lichens and mosses
• Early successional plants close to ground,
  break up rock and make soil
• Midsuccessional- herbs, grasses, low shrubs
• Late successional - trees
• Secondary reestablishment of biotic community.
  Begins where natural community has been
  disturbed, but soil sediment remains. Ex.
  Abandoned farmlands, burned forests etc.

33
How do species replace each other?

• Facilitation species behave in such a way that
  facilitates growing of other species. Ex
  legumes convert nitrogen to nitrates making soil
  more suitable
• Inhibition early species hinder establishment
  and growth of other species
• Tolerance ate successional plants are
  unaffected by plants at earlier stages of
  succession
• What is the role of Disturbance in succession?
• A disturbance is a discrete event in time that
  disrupts an ecosystem
• Natural disturbance fires, hurricanes, floods
• Intermediate disturbance hypothesis communities
  that experience frequent disturbance have
  greatest diversity of species

34
Ecological Stability and Sustainability

• Stability is maintained only by constant dynamic
  change in response to changing environmental
  conditions
• Inertia ability of living system to resist
  disturbance
• Constancy ability of system to maintain certain
  size within limits imposed by available resources
• Resilience ability of system to bounce back
  after external disturbance
• The signs of ill health in a stressed ecosystem
• Drop in primary productivity
• Increased nutrient loss
• Decline of indicator species
• Increased populations of insect pests
• Decline in species diversity
• Present of contaminants

35
General Information

• Pests any species that competes with us or food,
  invades lawns and gardens, destroys wood in
  houses, spreads disease, or is a nuisance
• Pesticides Chemicals developed to kill organisms
  that we consider undesirable
• Insecticides insect-killers
• Herbicides weed-killers
• Fungicides fungus-killers
• Nematocides roundworm-killers
• Rodenticides rat- and mouse-killers

36
Co-evolution

• Plants have been producing chemicals to ward off
  herbivorous predators for 225 million years. As
  herbivores adapt, so thy dont starve, plants
  adapt so that they survive. This is an example
  of co-evolution.

37
First Generation Pesticides

• Sulfur used as an insecticide since 500 BC
• Arsenic (As), lead (Pb), and mercury (Hg) by the
  1400s
• Nicotine sulfate extracted from tobacco leaves
  in the 1600s
• Pyrethrum obtained from the heads of
  chrysanthemum flowers
• Rotenone from the root of the derris plant

38
Second Generation Pesticides

• About 2.5 million tons of pesticides are used
  yearly worldwide. In the US, about 630 different
  biologically active (pest-killing) ingredients
  and 1,820 inert (inactive) ingredients are mixed
  to make 25,000 different pesticides products.
• DDT 1939, entomologist Paul Mueller discovered
  that DDT was a potent insecticide. It soon
  became the worlds most-used pesticide.
• Broad-spectrum agents toxic to many species
• Selective-spectrum agents effective against a
  narrowly defined group of organisms
• Persistence length of time in which pesticides
  remain deadly in the environment
• Biomagnification

39

• Spoil
• Unwanted rock and other waste materials produced
  when a material is removed from the earth's
  surface or subsurface by mining, dredging,
  quarrying, and excavation
• Overburden
• Layer of soil and rock overlying a mineral
  deposit. Surface mining removes this layer
• Open-pit mining
• Removing minerals such as gravel, sand, and metal
  ores by digging them out of the earth's surface
  and leaving an open pit.
• Area strip mining
• Type of surface mining used where the terrain is
  flat

40

• Dredging
• Type of surface mining in which chain buckets and
  draglines scrape up sand, gravel, and other
  surface deposits covered with water
• Contour strip mining
• Form of surface mining used on hilly or
  mountainous terrain
• Depletion time
• The time it takes to use a certain fraction,
  usually 80, of the known or estimated supply of
  a nonrenewable resource at an assumed rate of use

41

• Petrochemicals
• Chemicals obtained by refining (distilling) crude
  oil. They are used as raw materials in
  manufacturing most industrial chemicals,
  fertilizers, pesticides, plastics, synthetic
  fibers, paints, medicines, and many other
  products
• Tar sand
• Deposit of a mixture of clay, sand, water, and
  varying amounts of a tarlike heavy oil known as
  bitumen. Bitumen can be extracted from tar sand
  by heating. It is then purified and upgraded to
  synthetic crude oil

42

• Ore
• Part of a metal-yielding material that can be
  economically and legally extracted at a given
  time
• Shale oil
• Slow-flowing, dark brown, heavy oil obtained when
  kerogen in oil shale is vaporized at high
  temperatures and then condensed. Shale oil can be
  refined to yield gasoline, heating oil, and other
  petroleum products
• Breeder nuclear fission reactor
• Nuclear fission reactor that produces more
  nuclear fuel than it consumes by converting
  nonfissionable uranium-238 into fissionable
  plutonium-239

43

• Kerogen
• Solid, waxy mixture of hydrocarbons found in oil
  shale rock. Heating the rock to high temperatures
  causes the kerogen to vaporize. The vapor is
  condensed, purified, and then sent to a refinery
  to produce gasoline, heating oil, and other
  products
• Net energy
• Total amount of useful energy available from an
  energy resource or energy system over its
  lifetime, minus the amount of energy used (the
  first energy law), automatically wasted (the
  second energy law), and unnecessarily wasted in
  finding, processing, concentrating, and
  transporting it to users

44
How do minerals form?

• Magma crystallizes
• Sedimentary process
• Sedimentary sorting
• Precipitation
• Groundwater evaporates, leaving salts that
  precipitate
• Weathering process
• Water dissolves and removes soluble ions
• Residual deposits form

45
What are the environmental impacts of using
mineral resources?

• Scarring of land
• Collapse of land over underground mines
• Erosion of toxic mineral wastes
• Acid mine drainage

46
How is oil extracted and processed?

• Primary oil recovery
• Drill well, pump out lighter crude oil that flows
  out through pores
• Secondary oil recovery
• Pump high-pressure water into well to force out
  heavier crude oil
• Tertiary oil recovery
• Superheated steam forces out oil
• Detergent dissolves heaviest oil, which can then
  be pumped out

47
What are components of a nuclear fission reactor?

• Core contains fuel rods
• Uranium oxide fuel uranium-238
• Control rods move in and out of reactor to
  absorb neutrons
• Moderator slows neutrons so that chain reaction
  keeps going
• Coolant circulates to remove heat and produce
  steam for electricity

48
What types of energy do we use? Global and in U.S.

• Oil 30 (40 in US)
• Coal 22 (22 in US)
• Natural gas 23 (22 in US)
• Nuclear power 6 (7 in US)
• Hydropower, geothermal, solar, wind 6 (5 in
  US)
• Biomass 12 (4 in US)

49
Laws and Treaties
Chapter 15 1. CAFE (Corporate Average Fuel
Economy) requires new cars to meet certain
average fuel efficiency standards, averaged over
all cars produced. Between 1973 and 1985, the
average fuel efficiency doubled for new American
cars and rose 37 for all passenger cars on the
road because of CAFE.
50
Laws and Treaties Cont.

• Chapter 17
• NAPAP (National Acid Precipitation Assessment
  Program) established in 1980 to 1. coordinate
  government acid deposition research, 2. assess
  the costs, benefits, and effectiveness of the
  countrys acid deposition legislation and control
  program, and 3. report its findings to Congress.
• Clean Air Act passed in London in 1952, then by
  Congress in 1963, but did not have much effect
  until a stronger version of the law enacted in
  1970. The Clean Air Act of 1970empowered the
  federal government to set air pollution emission
  standards for automobiles and industries that
  each state was required to enforce. Stricter
  emissions standards were imposed by amendments to
  the Act in 1977 and 1990. Emissions of the six
  most common outdoor air pollutants decreased by
  31 between 1970 and 1998

51
The Case for Pesticides

• Pesticides save human lives Since 1945, DDT and
  other insecticides have probably prevented the
  premature deaths of at least 7 million people
  from insect-transmitted diseases.
• Pesticides increase food supplies and lower food
  costs About 55 of the worlds potential human
  food supply is lost to pests before or after
  harvest. Without pesticides, these losses would
  be worse, and could cause the prices of food in
  the US to rise nearly 50.
• Pesticides increase profits for farmers Overall,
  for every dollar spent on pesticides, there is an
  increase in US crop yields worth approximately
  two dollars.
• Pesticides work faster and better than
  alternatives Pesticides control most pests
  quickly and at a reasonable cost.
• The benefits overpower the health risks Safer
  and more effective pesticides are being developed.

52
The Case Against Pesticides

• Genetic resistance Insects can develop
  immunities to pesticides in just a few years.
• Broad-spectrum insecticides kill good organisms
  This includes killing natural predators and
  parasites that may have been maintaining the
  population of a pest species at a reasonable
  level.
• Unexpected outcome wiping out natural predators
  can also unleash new pests whose populations the
  predators had previously held in chick, causing
  other unexpected effects
• The pesticide treadmill A situation where
  farmers are forced to pay more for a pest control
  program that often becomes less effective as a
  genetic resistance develops
• Although the use of synthetic pesticides has
  increased 33-fold since 1942, it is estimated
  that more of the US food supply is lost to pests
  today than in the 1940s.
• The estimated environmental, health, and social
  costs of pesticide use in the US range from 4
  billion to 10 billion per year
• Alternative pest control practices could halve
  the use of chemical pesticides on 40 major US
  crops without reducing crop yields.
• A 50 cut in US pesticide use would cause retail
  prices to rise by only about .2 but would raise
  average income for farmers about 9.

53
Environmental Effects

• Less than 2 of the insecticides applied to crops
  by aerial spraying or by ground spraying actually
  reach the target pests
• Some pesticides can harm wildlife DDT had
  harmful effects in the environment when it
  biologically magnifies in food webs. This
  resulted in certain birds being listed on the
  endangered species list in the US because of
  fatal effects.
• Each year 20 of honeybee colonies in the US are
  wiped out by pesticides, while another 15 are
  damaged, costing farmers over 200 million
  annually.

54
Human Health Effects

• An estimated 25 million agricultural workers in
  developing countries are seriously poisoned by
  pesticides each year. 220,000 deaths result.
• In developed countries an estimated 300,000 farm
  workers suffer from pesticide-related illnesses
  yearly. 250,000 Americans get sick each year
  from home misuse of pesticides.
• Approximately 13 of vegetable and fruits
  consumed in the US may contain illegal pesticides
  and levels of approved pesticides above their
  legally allowed limits.
• At least 75 of the active ingredients approved
  for use in US pesticide products cause cancer in
  test animals.

55
Pesticide Regulation in the US

• All commercial pesticides must be approved by the
  EPA for general or restricted use
• When a pesticide is legally approved for use on
  fruits or vegetables, the EPA sets a tolerance
  level, which specifies the amount of toxic
  pesticide residue that can legally remain on the
  crop when the consumer eats it.
• According to a National Academy of Sciences
  study, federal laws regulating the use of
  pesticides in the US are inadequate and poorly
  enforced by the EPA, FDA, and USDA
• Exposure to pesticide residues in food causes
  4,000-20,000 cases of cancer per year in the US
• A 1993 study of pesticide safety by the US
  National Academy of Sciences urged the government
  to do the following things
• Make human health the primary consideration for
  setting limits of pesticide levels allowed in
  food
• Collect more an better data on exposure to
  pesticides for different groups, including farm
  workers, adults, and children
• Develop new and better test procedures for
  evaluating the toxicity of pesticides, especially
  for children
• Consider cumulative exposures of all pesticides
  in food and water, especially for children,
  instead of basing regulations on exposure to a
  single pesticide

56
Progress Made with the Passage of the 1996 Food
Quality Protection Act

• Requires new standards for pesticide tolerance
  levels in foods, based on a reasonable certainty
  of no harm to human health
• Requires manufacturers to demonstrate that the
  active ingredients in their pesticide products
  are safe for infants and children
• Allows EPA to apply an additional 10-fold safety
  factor to pesticide tolerance levels to protect
  infants and children
• Requires the EPA to consider exposure to more
  than one pesticide when setting pesticide
  tolerance levels
• Requires the EPA to develop rules for a program
  to screen all active and inactive ingredients for
  their estrogenic and endocrine effects by 1999.

57
Solutions

• Cultivation practices
• Crop rotation
• Planting rows of hedges or trees around fields to
  hinder insect invasions
• Adjusting planting times so that major insect
  pests either starve or get eaten by their natural
  predators
• Planting trap crops to lure pests away from the
  main crop

58
Solutions cont.

• Genetically resistant plants
• Plants and animals that are genetically resistant
  to certain pests insects, fungi, and diseases can
  be developed
• Genetic engineering can be used to build pest
  resistance into crops and thus reduce the need
  for pesticides
• Using natural enemies to help control pests
• Biological control using predators, parasites,
  and pathogens to regulate pest populations
• Using biopesticides to control pests

59
Solutions cont.

• Insect birth control, sex attractants, and
  hormones
• Males of some insect pest species can be raised
  in the laboratory, sterilized by radiation or
  chemicals, and then released into an infested
  area to mate unsuccessfully with fertile wild
  animals
• Hot water the Aqua Heat machine sprays boiling
  water on crops to kill weeds and insects
• Radiation exposing certain foods after harvest
  to gamma rays emitted by radioactive isotopes
  will extend food shelf life and kill harmful
  insects, parasitic worms, and bacteria

60
Integrated Pest Management

• Integrated pest management (IPM) in this
  approach, each crop and its pests are evaluated
  as parts of an ecological system. Then a control
  program is developed that includes a mix of
  cultivation and biological chemical methods
  applied in proper sequence with the proper
  timing.
• The overall goal is not to eliminate pest
  populations but to reduce crop damage to an
  economically tolerable level.
• IPM requires expert knowledge about each pest
  situation, and is much slower acting than
  conventional pesticides.
• Although long-term costs are typically lower than
  the costs of using conventional pesticides,
  initial costs may be higher.
• Scientists urge the USDA to promote IPM by the US
  by
• Adding a 2 sales tax on pesticides and using
  revenue to fund IPM research and education
• Setting up a federally supported IPM
  demonstration project on at least one farm in
  every county
• Training USDA field personnel and county farm
  agents in IPM so that they can help farmers use
  this alternative
• Providing federal and state subsidies to farmer
  who use IPM
• Gradually phasing out subsidies to farmers who
  depend almost entirely on pesticides, once
  effective IPM methods have been developed for
  major pest species