Chapter 50
Ecology & The
Biosphere
By: Justin Martinez,
Izabela Kolodziejska, Anne
Simonetti, Ashley Davis
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 earth’s 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.
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 weren’t killed were
affected since their food was killed.
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
Carson’s 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.
Carson’s 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”.
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.
SoIl
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 wouldn’t
exist, and without plants animals
wouldn’t 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.
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 Carson’s
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 couldn’t
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.
•
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.
“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