Environmental Science
I.
Environmental Science is the study of how humans
interact with the environment.
a.
Many aspect of environmental science is solving
environmental problems
b.
ENVIRONMENT refers to everything that surrounds us
1.
Natural Resources are substances that living
things can use which can include sunlight, air, water, soil, minerals, plants,
and animals, and of course, fossil fuels
·
Nonrenewable Resources
are resources that cannot be replaced in a timely manor such as fossil fuels
·
Renewable Resources
are resources that are continually being replaced such as sunlight
After World War II, many
people moved to what were called the “Suburbs”. This term actually means “below urban”. Many wished to move from fast city paced lifestyles to a slower country
pace. In doing so, construction, and
many urban comforts were brought to these areas. This growth continued for over 40 years and now we are seeing
problems that were at one time only issues in the cities. These problems include over crowding of humans,
destruction of animal habitats, pollution, limited water supplies, and other
resource depletion.
I.
Resource Depletion
can occur in several different ways
a.
Pollution
is the introduction of harmful levels of chemicals, or waste materials into the
environment
b.
Extinction
means that the last individual member of a species has died and the species is
gone forever; this can occur by natural means or by pollutants
II.
Biosphere is the layer of life around the Earth.
a.
The Biosphere extends from the surface of the Earth
to about 5 miles above the surface
b.
The Biosphere supports many different populations
of both plant and animal.
·
Human populations can be divided into two
categories;
~ Developed countries
have highly industrialized areas and high incomes
~ Developing countries
are less industrialized and the have a much lower average income.
What
is Science?
a.
Pure Science seeks to answer questions
about how the natural world works such as Research Biology
b.
Applied Science uses the information provided by
pure science to solve problems such as technology
·
Environmental Scientist use information provided
by the Pure Science to answer questions, hence, an Environmental Scientist is
an Applied Scientist
II.
Communicating and using Science
a.
There are several steps used to answer scientific
questions;
·
Observing
·
Hypothesizing
·
Predicting
·
Experimenting
·
Data (which can be in graph form; log book, or
illustration)
·
Conclusion
I.
Ecosystems are all the different organism living
in a certain area along with their physical environment and factors.
a. Biotic
Factors are the living parts of an ecosystem such as animals, plants and
microorganisms
b. Abiotic Factors are the nonliving parts of
the ecosystem that influence living things such as temperature, sunlight,
humidity, water supply, soil type and mineral nutrients
The
Breakdown of the Ecosystem
1.
The Organism is the one
individual living thing
2.
The Species is a group of
organisms that are able to produce fertile offspring and share common genes,
which cause them to resemble each other.
3.
The Population is a group of
individuals of the same species living in a particular place.
4.
A Community is a group of
interacting populations of different species.
5.
An Ecosystem is all living
organisms in a certain area as well as their physical environment.
·
A Niche is it’s way of life
(“lifestyle”)
·
A Habitat is the actual place
an organism
Lives
1. Predation
is one organism kills and eats another organism.
·
Prey is the organism that is eaten by the predator
·
Predators are the animals that do the eating
2. Competition
occurs when two or more organisms of the same or different species attempts to
use the same limited resource.
3. Parasitism
is the relationship between a parasite and it’s host
·
Parasites
are organisms that live in or on another organism and feed on it without
immediately killing it
·
Hosts
are the organisms that the parasites take their nourishment from
4. Mutualism
is a cooperative partnership between two species in which both species benefit.
5. Commensalism
is a relationship in which one species benefits and the other is neither harmed
nor helped such as the interaction between remoras and sharks.
Evolution by Natural Selection
1.
All organisms have the ability to produce more
offspring than can possibly survive
2.
The environment contains things that kill
organisms; it is often hostile, hot or cold, dry or flooded, Predators are
common, and the resource needed to survive and reproduce are often in short
supply and because of this individuals compete for these limited resources so
there is a “struggle for existence”.
3.
Individuals vary, or differ in their traits. They may differ in size, coloration, running
speed, resistance to disease and many other traits. This variation must be inherited for it to influence natural
selection.
4.
Some inherited traits give individuals an
advantage in coping with environmental challenges, allowing them to survive
longer and produce more offspring.
Organisms with these traits are “naturally selected”
5.
Because individuals with advantageous traits have
more offspring, each new generation contains a greater proportion of the
offspring with these traits than did the precious generation. Since these traits are inherited, offspring
of individuals without the trait become less numerous. Gradually, over generations, the population
contains more and more individuals with the advantageous trait. This process is
Evolution by Natural Selection.
a.
Producers
is an organism that makes its own food .
·
Autotrophs
is another term for producer
b.
Herbivores
are consumers that eat only producers
c.
Carnivores
are consumers that eat only other consumers
·
Omnivores are consumers that eat both consumers
and producers
d.
Decomposers
are consumers that get their food by breaking down dead organisms
II.
Food Chains are a sequence in which energy is
transferred from one organism to the next as each organism eats another.
a.
Typically, the energy is reduced as it is passed
on to each organism.
Water Cycle
I.
The Water Cycle is the process where the Earth’s
water moves between the Earth’s Surface and Atmosphere.
a. The
energy for this process is provided by the Sun, which powers it.
Carbon Cycle
I.
Carbon is essential for the production of
proteins, fats and carbohydrates
a.
Carbon enters the ecosystem when producers take in
Carbon dioxide from the atmosphere during photosynthesis.
b.
When consumers break down the food molecule during
cellular respiration, the carbon is released back into the atmosphere as carbon
dioxide.
II.
Fossil fuels such as coal, oil, and natural gas
are stored carbon left over from the bodies of plants and animals that died
millions of years ago
a.
When these fossil fuels are burned they release
the carbon into the atmosphere and returns to the original form of carbon
dioxide.
The Nitrogen Cycle
I.
Nitrogen is one of the most plentiful elements in
our ecosystem.
a.
It is used for building proteins
b.
Nitrogen in it’s natural form in the atmosphere is
useless to us and many other organisms
c.
Organisms such as Nitrogen Fixing Bacteria are
able to convert nitrogen as in a useable form
Ecosystem Change
I.
Succession is a regular pattern of changes over
time in the types of species in a community.
a.
Succession
may take hundreds or thousands of years
b.
Each new community that forms make it difficult
for the previous community to survive
c.
Climax Communities
are the ones that eventually form if the land is left undisturbed.
d.
Primary Succession is succession
that occurs on surfaces where no ecosystem existed before
·
This is much slower than secondary succession
because it begins where there is no soil.
e.
Secondary Succession
occurs in areas where a community existed previously.
f.
Old Field Succession
occurs when farmland is abandoned
·
Pioneer plants
are the plants that move in to a newly available area and start the process of
succession
a.
The Jack Pine can only release it seeds unless it
is exposed to the intense heat of fire
b.
Fire also clears out the underbrush that can
inhibit the growth of other plants
Various Ecosystems
I.
Biomes are areas that have distinctive climates an
organisms
a.
Tropical rainforests
occur in a belt around the Earth near the Equator.
·
They are humid and warm and get about 100 inches
of rain per year.
·
There is little seasonal variation per year.
·
Because of such a warm moist environment, decay of
plants and animals is rapid; these released nutrients are immediately used so
there is little build up on the forest floor.
~This is why the soil
level are shallow
~Trees develop prop
roots as they need extra support in the thin soil.
·
One plant adaptations is the Canopy;
·
This is formed from the taller trees of 100 feet
or more
·
They filter out up to 95% of the sunlight
·
Animal adaptations include camouflage, hunting and
gathering techniques, and poisons
b.
Temperate Forests
occur in North and South America, Australia and New Zealand
·
The Pacific Northwest is home to North America’s
only Temperate Forest.
~These forests have
dense undergrowth of ferns, heavy moss cover and large evergreen trees.
~They are cool, humid
forests
c.
Temperate Deciduous Forests are located in areas
where there are extreme seasonal changes.
·
They receive between 30 – 100 inches of rain per
year
·
Many of the trees will loose their foliage at one
point during the year.
·
Plants and animals adapt to the climate changes by
migrating, camouflage, hibernating, or becoming dormant
d.
Taiga is also known as the “Boreal Forest” and is
located in the Northern hemisphere just below the Arctic Circle
·
This region may have a warm season as short as 50
days
·
Most of the trees are conifers which can stand the
extreme cold
·
Many of the larger animals migrate to adapt to the
extreme climate
e.
Savannas are
found in the tropics near the equator but they get to little rain to support
trees
·
The west African plains contain the greatest
collection of large grazing animals on earth
f.
Temperate Grasslands
are found in the interiors of continents where there is too little rainfall for
trees to grow.
·
the names of this kind of area can be various such
as steppes, shortgrass prairie, and pampa
·
The height of the grassland plants depends on both
the roots of the grasses and the rainfall
g.
Chaparral is a biome that occus in the mid
latitudes about 30 degrees north and south of the equator.
·
this area is known for dry hot summers and mild
wet winters.
·
The plants have adapted by being low lying evergreen shrubs; the leaves are tough to
reduce water loss and they contain oils.
~these oils also make
them flammable which takes advantage of natural fires
~when fires occurred,
the low lying shrubs could regenerate before any type of tree that could
inhibit their growth
·
Animals adapt mostly by camouflage
h.
Deserts are areas that receive less than 10 inches
of precipitation per year.
·
plant adaptations include methods of saving and
conserving water
~plant roots are usually
very shallow and spread out widely
~this allows them to be
Drought Resistant
·
animals often adapt by Estivating
~this is burying
themselves in the ground and sleeping through the dry season
~most animals are active
only at night
i.
Tundra is
a biome without tall trees that lies north of the arctic circle.
·
underneath the top few inches of soil, there is a
layer called permafrost which is permanently frozen soil
~plants have adapted to
this by spreading their roots above this line
~these plants grow and
flower very quickly to make good use of the short season
·
animal adaptation includes migration, camouflage,
and hibernation
Freshwater Ecosystems
I.
Freshwater ecosystems include lakes and ponds,
rivers, streams and wetlands.
a.
Lakes and ponds are broken down in zones
·
Littoral Zones
is the shallow area close to shores
1. this
area is very nutrient rich
·
Benthic zones are the
areas of the bottom of the body of water
1. this
area is typically covered with dead and decaying organisms
2. this area is inhabited by decomposers, insect
larva, and clams
b.
Plant adaptations include the ability to root in
muddy bottoms and grow tall enough that they extend above the surface such as
cattails
c.
Animal adaptations are varied; an example could be
the catfish whiskers used to sense food in the murky waters
II.
Wetlands are areas of land that are covered with
water for at least part of the year.
a.
Many of our commercial and recreational fishing
depends on wetlands
b.
Wetlands also act as a sponge and filter for
runoff
1. Swamps
contain woody plants and/or shrubs
2. Marshes
contain non-woody plants
c.
Plants often adapt according to the type of
wetland but don’t change their identity
1. arrowhead
plant changes in according to the flow of the water
~grasslike and
completely submerged for fast flowing river
~floating like a
Lilly pad for slower water
~aerial which
rises above the water line in calm waters
Marine Ecosystems
I.
Estuaries are areas where freshwater and salt
water mix
a.
Animals and plants must adapt to both fresh and
salt water environments
b.
Organisms also must adapt to the constant change
in these factors
II.
Coral reefs are limestone island in the sea that
are built by coral animals in colonies
a.
These animals have a symbiotic relationship with
algae which provides food
b.
Due to this they need to be in shallow enough
water to photosynthesize
c.
They are also sensitive to temperature so the
water must be warm
d.
They are generally omnivores so there must also be
plankton present
III.
The ocean covers over 70% of the earth’s surface
a.
it is a mixture of organic and inorganic
substances
b.
it balances itself with a delicate chemical
buffering system
1.
this system is also sensitive to temperature
changes also
c.
Human exploration has only delved into the first
30% of the ocean
Freshwater Pollution
I.
Water pollution is the introduction of chemical,
physical, or biological agents into water that degrades the quality of the
water and affects the organisms that depend on it
a.
Water pollution generally has two causes
1.
industrialization
2.
human population explosion
b.
Point pollution is pollution that is discharged
from a single source
1.
generally these are easy to trace and address
c.
Nonpoint Pollution is pollution that comes from
many sources rather than from a single specific site.
1.
It can come from almost anywhere; such as lawns,
pesticides, fertilizers etc
2.
It is very difficult to locate, regulate and
control
d.
Pollutants can come in many forms and some don’t
have to be chemical
1.
Thermal Pollution is caused when water discharge
is at a temperature higher than the surrounding ecosystem
e.
Pollutants can cause damage immediately or at a
later date
1.
Some pollutants can cause immediate damage such as
acids
2.
Some will cause an increase of nutrients in
the water, which will over feed the present organisms, which will in turn
increase their waste products: this is
called Artificial Eutrophication
3.
Biological magnification can occur and cause
a delayed effect such as DDT.
~DDT was used in the
1950s to control flying pests in the suburbs; Birds ate the dying insects,
built up the toxin in their systems and eventually it presented itself when the
birds tried to hatch clutches of eggs; when they incubated them by sitting on
them the shells were too thin and would crack.
I.
Waste water is water that has been used and then
(hopefully) treated before returning it to a water body
Pathogens
I.
Pathogens are disease causing organisms usually
bacteria, viruses, and parasitic worms.
a.
Pathogens can enter water in untreated wastewater
or animal feces
1.
Cholera, hepatitis, and typhoid are typical
Air Pollution
I.
Air Pollution occurs when harmful substances end
up in the air at unhealthy levels.
a.
Most air pollution is the result of human
activities
b.
Natural sources of air pollution include
volcanoes, dust, pollen, and spores
II.
There are several types of pollutants
a.
Primary pollutants
are pollutants that is put directly into the air by human activity such as soot
from smoke
b.
Secondary pollutants
are formed when a primary pollutant comes into contact with other primary
pollutants such as ozone
1.
Ozone
is created when the emissions from cars, truck and natural sources react with
the u.v. rays of the sun and then mingle with the oxygen gas in the atmosphere.
III.
Causes of Air pollution
a.
1/3 of our air pollution comes from gas burned in
motor vehicles
1.
Carbon Dioxide
is formed from this combustion and interferes with the bloods ability to carry
Oxygen and if in large enough quantities can cause death
2.
Carbon Dioxide
in high quantities can also cause possible birth defects
b.
Industrial Air Pollution
is caused by the burning of fuels to provide the energy needed.
1.
Over one third of all nitrogen oxides
and one third of the particulates that pollute the air
2.
Nitrogen Oxide
can make the body vulnerable to respiratory infections, lung disease and
possible cancer
~this contributes to
acid rain and can cause corrosion
3.
Sulfur Dioxide
contributes to acid rain, kill plants and cause respiratory irritation
4.
Volatile Organic Compounds(VOC)
vaporize readily and can contribute to smog formation; can also cause serious
health problems such as cancer and harms plants
5.
Particulate matter (P.M.)
are tiny particles of liquid or solids such as smoke, dust, or acid droplets
~they can form clouds
that reduce visibility are cause respiratory ailments
~there is thought that
some particulates can cause cancer
c.
Thermal Inversions
can concentrate air pollution in areas
1.
When air pollution hangs over urban areas
and reduces visibility it is called SMOG
2.
Cities that suffer most from smog have dense
traffic and are located in dry sunny areas
3.
Typically, the higher in the atmosphere you go,
the cooler the temperature
4.
With Thermal Inversions the air above is warmer
than the air below and traps pollutants near the Earth’s surface
Acid Rain
I.
Acid Precipitation is highly acidic precipitation
(rain, sleet, or snow) that results from the burning of fossil fuels
a.
When fossil fuels are burned they relate oxides of
sulfur and nitrogen’s by-products
1.
When the oxides combine with water in the
atmosphere they form sulfuric acid, and nitric acid
2.
It is considered Acidic if the pH is less than 5.6
~Often in the U.S. rain
is recorded at 3.5 to 4.0 and is considered “soda-pop” as it is the pH of many
drinks
II.
How Acid Rain affects Ecosystems
a.
When acid precipitation falls on a lake and
changes the water’s pH it can kill aquatic plants, fish and other animals
1.
It will also cause the aluminum to leach out of
the soil surrounding the area
~The aluminum accumulates on the gills of
fish, which stimulate mucus production
~Many fish slowly
suffocate from the buildup of mucus on their gills
b.
Acid Shock
can occur when acidic snow that accumulated all winter melts and rushes into
lakes and other bodies of water
1.
Because of this Spring is often the toughest time
of the year for acid precipitation
2.
It can wipe out whole populations of fish
3.
Acid Shock
can affect the reproduction of the amphibians and they will produce fewer eggs
and many of these do not hatch
c.
Lime (the mineral) is one solution for small-scale
pollution.
1.
This substance can be sprayed in small amounts to
neutralize the affected waters
Atmosphere and Climate
I.
Atmosphere is a thin layer of gases that covers
the earth
a.
Composition of the Atmosphere
1.
78% Nitrogen
2.
21% Oxygen
3.
1% other substances such as water vapor, argon,
carbon dioxide, neon, helium
II.
Five layers of the Atmosphere
a.
Troposphere
extends from the surface to about 6 miles
1.
this contains about 90% of the Earth’s gasses
2.
this is where most weather occurs
b.
Stratosphere extends
about 30 miles above the Earth
1.
The winds in the stratosphere don’t swirl and are
not as dramatic in this layer
2.
Commercial airliners usually travel in the lower
levels of this layer
3.
The Ozone is contained in this
layer, which protects us from harmful u.v. Radiation
c.
The Mesosphere extends to approx. 50
miles above the Earth’s surface
d.
The Thermosphere extends after the Mesosphere
up to 310 miles
e.
The Exosphere and Ionosphere
then fade out to space beyond the Thermosphere
Climate
I.
Climate
is the average weather in an area over a long period of time
a.
Weather is
what is happening in the atmosphere at a particular place and time
b.
Climate is determined by factors including latitude,
air circulation, ocean currents, and geography
1. Latitude strongly influences
climate because the amount of solar energy an area receives
·
Latitude is the distance from the equator,
measured in degrees north or south of the equator.
·
More solar energy falls on the areas closest to
the equator
2.
Circulation affects
climate by three basic principles which are;
~Cold air sinks and
warms as it sinks
~Warm air rises and
cools as it rises
~Warm air can hold
more water vapor than cold air can
·
Solar energy will warm the ground which warms the
air above it
·
Warm air rises and cooler air moves in to replace
it which causes wind
·
This circulation pattern determines global
precipitation
3.
Ocean Circulation
redistribute warm and cool masses of water and these are triggered by the
moving masses of air above the water
4.
Geography
can alter or re-route the patterns of wind and precipitation; elevation can
change local temperature
Greenhouse Effect
I.
The Greenhouse Effect occurs when sunlight streams
through the atmosphere and heats the Earth.
a.
As heat radiates up from the Earth, some of it
escapes into space
b.
The rest of the heat is trapped by gases in the
troposphere and warms the air
1.
only certain gases can trap heat this way, they
are called Greenhouse Gases
·
Water vapor
·
Carbon dioxide
·
Chlorofluorocarbons (CFC)
·
Methane
·
Nitrous oxide
II.
Ozone is our barrier to the damaging u.v. rays of
the sun
a. CFC’S were determined in the 1970’s to be
damaging the ozone layer and creating a “hole”