Chapter 50 Ecology

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Chapter 50Ecology The Biosphere

• By Justin Martinez, Izabela Kolodziejska, Anne
  Simonetti, Ashley Davis

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Ecology is the study of interactions between
organisms and their environment. Rachel Carson
shows her readers that in an environment one
poisoned creature could upset the whole system.
Carson states In this unseen world, minute
causes produce mighty effects.

• Ecology and evolutionary biology are closely
  related sciences. Events that occur in the
  framework of ecological time (minutes, months,
  and years) will translate into effects over the
  longer scale of evolutionary time ( decades,
  centuries , millennia).
• In Silent Spring, Rachel Carson writes about the
  shocking and dangerous reduction of all the
  earths natural resources for balancing insect
  populations. She recognized that chemical
  poisoning kills insects only for a short span of
  time the insects will begin the develop
  resistance to these chemicals, an evolutionary
  effect. The chemicals kill the natural predators
  of the insects and allow insects to grow greater
  and greater in number.

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• A population is a group of individuals of the
  same species living in a particular geographic
  area. Population ecology focuses on factors that
  affect how many individuals of a particular
  species live in an area. A community contains all
  the organisms of all the species that inhabit a
  particular area.
• Throughout Silent Spring, Rachel Carson discusses
  various populations and communities that were
  affected greatly by the use of pesticides. The
  massive spraying operations had caused most of
  the bird population to die. These birds were
  killed in massive number because the birds ate
  the insects and worms that contained DDT. The
  salmon population of the Miramichi river
  community was also greatly affected by a massive
  spraying campaign that was supposed to kill off
  the spruce budworm that was threatening forest
  life. A massive amount of the salmon population
  was killed by these pesticides. The whole river
  community was affected. Even the salmon that
  werent killed were affected since their food was
  killed.

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• The environment of any organism includes abiotic
  and biotic components. Abiotic components are
  nonliving components such as temperature, light,
  water, and nutrients. Biotic components are
  living components including all organisms.
• In her book, Rachel Carson writes about the
  affects of the insecticides on abiotic and biotic
  components.
• An abiotic component that was affected, for
  example, was water. The use of pesticides caused
  water pollution. The chemicals from these
  pesticides were washed into bodies of water and
  seeped into the soil.
• Carson tell us that it is not possible to add
  pesticides to water anywhere without threatening
  the purity of water everywhere.
• Biotic components were also affected by the
  pollution of the groundwater. An example of this
  in the book is when poisonous chemicals flowed
  through the groundwater from a manufacturing
  plant in Colorado to a farming district. The
  wells became poisoned, thus causing the death of
  animals and crops.

• Environmentalism is advocating for the protection
  or preservation of the natural environment. We
  need to understand the complicated relationships
  between organisms and the environment in order to
  address environmental problems. These
  relationships could be understood through the
  science of ecology. 
• In 1962, our society became aware of certain
  environmental issues through Rachel Carsons
  Silent Spring. Rachel Carson warned the public
  that the widespread use of pesticides caused
  population declines in many organisms that were
  non-target species. These pesticides contaminated
  soil, water, and food.
• Carsons says the control of nature is a phrase
  conceived in arrogance born of the Neanderthal
  age of biology and philosophy, when it was
  supposed that nature exists for the convenience
  of man.

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Interactions between organisms and the
environment limit the distribution of species

• Biotic Factors
• In Silent Spring by Rachel Carson, DDT and other
  insecticides were the cause of countless deaths
  amongst flourishing species.
• The insecticides would poison the animals once
  they encountered the deadly chemicals, attacking
  their nervous systems and causing them to die
  slowly from the outrageous amounts of poison that
  their bodies took in.
• The insecticides were somewhat like what a
  disease would do if it were naturally occurring
  and not introduced by man. Like a disease, the
  insecticides caused the rapid deaths of animals,
  and the unstoppable spreading of these life
  threatening chemicals through the interaction of
  species with one another. The insecticides caused
  a mass disturbance, which is a force that changes
  a biological community and usually removes
  organisms from it.
• An example in the book where insecticides portray
  a deadly disease that cause life long effects
  occurs when Endrin was used to have a house
  sprayed for cockroaches. The child was removed
  from the house during the spraying of the
  chemical. The house was then cleaned and the
  child was taken back inside the house. The child
  went into convulsions and lost consciousness
  causing him to go into a vegetative state
  permanently.

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S o I l

• Soil limits the distribution of plants and thus
  of the animals that feed upon them. In streams
  and rivers, the composition of the substrate can
  affect water chemistry, which in turn influences
  the resident organisms.
• Soil is created from living and non-living
  things. Without it land plants wouldnt exist,
  and without plants animals wouldnt survive.
• Insecticides damage the soil and prevent it from
  following through with vital processes one of
  these being nitrification which makes nitrogen in
  the air available to plants to help them grow.

Insecticides also alter the soil by killing off
certain organisms while allowing the organisms
who survive to ultimately become over populated
and pestilences. Pesticides remain in the soil
for up to twelve years after one spraying
therefore after countless sprayings it is almost
impossible to remove the chemicals from the soil,
which contaminates the crops growing in this
soil.
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• Water
• -The dramatic variation in water availability
  among habitats is another important factor in
  species distribution. Freshwater and marine
  organisms live submerged in aquatic environments,
  but most are restricted to either freshwater or
  saltwater habitats by their limited ability for
  osmoregulation. Water is essential for the
  well-being of all organisms, and in Rachel
  Carsons Silent Spring, the gruesome effects of
  radioactive wastes, nuclear explosions, domestic
  waste, and chemical sprays are shown.
• -Because chemical sprays are carried through the
  air from forest spraying, or seep into nearby
  rivers and streams, water is contaminated,
  causing the innumerable deaths of fish and other
  species living in these waters. Chemicals were
  found stored in the fat of fishes.
• -Ground water is the most disturbing case of all.
  Ground water comes from rain fall that settles in
  the earth and creates its own underground sea.
  This water is contaminated with chemicals, thus
  poisoning the earth and whatever streams and
  rivers it enters. All the water on earth was once
  ground water, therefore all the water on earth is
  being affected by pesticides.
• -An example of this was when the Rocky Mountain
  Arsenal of the Army Chemical Cops, located near
  Denver, began to manufacture war materials. Eight
  years later the facilities of the arsenal were
  leased to a private oil company for the
  production of insecticides. After this,
  mysterious reports came in stating that farmers
  several miles away from the plant began to report
  unexplained sickness among livestock and crop
  damage. The irrigation waters on these farms were
  derived from shallow wells. When the well waters
  were examined they were found to contain an
  assortment of chemicals including 2,4-D, thus
  explaining the mysterious events happening on
  near by farms.
• -A second example includes the case of Clear Lake
  where DDD was dumped into the lakes to stop gnats
  and other unwanted organisms in or around the
  lake. The pesticide was stored in all the animals
  of lake from plankton to birds. Species were
  dying off rapidly and the chemical couldnt be
  detected because it had gone into the fabric of
  life the lake supports. Twenty-three months went
  by, and still the chemical was still present in
  plankton.

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• As previously mentioned, Rachel Carson brings up
  the problem of water pollution by pesticides in
  her novel Silent Spring.

90 of wetlands have been destroyed in some
regions due to draining and filling. Many lakes
are now faced with algal blooms, oxygen deletion,
and fish kills because pollution by runoff from
fertilized land and dumping of wastes. Filling,
dredging, and pollution from upstream have
disrupted estuaries worldwide.
Pollution of our waterways comes from
laboratories, reactors, and hospitals that
release radioactive wastes. Chemical wastes are
discharged from factories and domestic wastes are
yielded from towns and cities. Chemical spraying,
as Carson writes, has added more chaos to this
mess.
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• The human race is too ingenious for its own good
  Man has acquired the power to alter the nature
  of his own world.
• -Rachel Carson