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Ecosystems and Biomes
Table of Contents
Energy Flow in Ecosystems
Cycles of Matter
Biogeography
Biomes
Aquatic Ecosystems
Ecosystems and Biomes
Energy Roles
Recall that a self-sustaining ecosystem has four
characteristics:
1. A constant source of energy (usually the sun)
2. Transfer of energy into organic compounds
(usually through photosynthesis)
3. Interactions between biotic factors
(predator/prey, mutualism, commensalism)
4. Cycling of materials (water cycle, nitrogen
cycle, oxygen/carbon dioxide cycle,
nutrient cycle)
Ecosystems and Biomes
Energy Roles
In order for these four factors to be met, organisms within an
ecosystem must fit into one of three roles:
Decomposers
Producers
Consumers
Ecosystems and Biomes
Producers
Producers —organisms
that make (produce) their
own food.
-Usually, producers use
energy from the sun to turn
water and carbon dioxide
into sugar.
-This process is called
photosynthesis.
-Producers include:
Plants
Algae
Cyanobacteria
Ecosystems and Biomes
Consumers
Consumers —organisms that
get energy by feeding on other
organisms. Three types:
Herbivores —eat only plants
Carnivores —eat only animals
Omnivores —eat both plants
and animals
Ecosystems and Biomes - Energy Flow in Ecosystems
Consumers
Click the Video button to watch a movie about consumers.
Ecosystems and Biomes
Decomposers
Decomposers —break down
wastes and dead organisms
and return raw materials to
the ecosystem.
Decomposers include mostly
bacteria and fungi such as
mushrooms.
Ecosystems and Biomes
Food Chains and Food Webs
To sustain any ecosystem, energy must
be transferred through the many
organisms that live in the ecosystem.
The movement of energy through an
ecosystem can be shown in diagrams
known as food chains and food webs.
Food chain —shows a series of events
in which one organism eats another and
obtains energy. Food chains always
start with a producer. Each organism
that follows is known as a first, second,
and third level consumers etc. Food
chains show just one path of energy.
C3
C2
C1
Ecosystems and Biomes
Food Webs
Food webs —show
the many overlapping
food chains in an
ecosystem. In a food
web, an organism can
play more than one
role.
Who is the only
C5 consumer? Is there a
C7?
Can you find this
food chain in the
food web?
Can you find an animal that
is both a C2 and C3
consumer?
Ecosystems and Biomes
Ecosystems and Biomes - Energy Flow in Ecosystems
Food Chains and Food Webs
The movement of energy though an ecosystem can be
shown in diagrams called food chains and food webs.
Ecosystems and Biomes
Food chain/food web
Flip chart
Ecosystems and Biomes
Energy Pyramids
Energy Pyramids show
the amount of energy that
moves from one feeding
level to another in a food
web.
The most amount of
energy is available at the
producer level.
The amount of energy
decreases at each level.
Ecosystems and Biomes
Only 10% of the energy
available at one level is
transferred to the next
level.
The other 90% is used
by the organism or lost
to the environment in
the form of heat.
Therefore, each level
can support fewer
and fewer organisms.
Ecosystems and Biomes - Energy Flow in Ecosystems
Building Vocabulary
A definition states the meaning of a word or phrase by telling
about its most important feature or function. After you read
the section, reread the paragraphs that contain definitions of
Key Terms. Use all the information you have learned to write
a definition of each Key Term in your own words.
Key Terms:
Examples:
energy
food
chain
pyramid
consumer
food
web
herbivore
producers
omnivore
carnivore
scavenger
Anaenergy
In
food chain,
pyramid
a consumer
shows how
could
much
beenergy
an herbivore,
moves
an omnivore,
from
one level or
to a
another
carnivore,
in a food
including
web,abeginning
scavenger.
with the producers.
decomposer
Decomposers are nature’s recyclers.
Ecosystems and Biomes - Energy Flow in Ecosystems
Links on Food Chains and Food Webs
Click the SciLinks button for links on
food chains and food webs.
Ecosystems and Biomes
End of Section:
Energy Flow in
Ecosystems
Ecosystems and Biomes
Cycles of Matter
Remember that one of the four characteristics of a selfsustaining ecosystem is the cycling of matter. This happens
through three main processes:
The Water Cycle—the process by which water
moves from the Earth’s surface to the
atmosphere and back.
The Carbon/Oxygen Cycle—carbon dioxide
and oxygen are recycled through processes that
are linked together by producers and consumers.
The Nitrogen Cycle—nitrogen cycles from the
air, to the soil, into living things and back into the air.
Ecosystems and Biomes - Cycles of Matter
The Water Cycle
The processes of evaporation, condensation, and
precipitation make up the water cycle.
Ecosystems and Biomes - Cycles of Matter
Water Cycle Activity
Click the Active Art button to open a browser window and
access Active Art about the water cycle.
Ecosystems and Biomes - Cycles of Matter
The Carbon and Oxygen Cycles
In ecosystems, the
processes by which
carbon and oxygen are
recycled are linked.
Producers, consumers,
and decomposers play
roles in recycling carbon
and oxygen.
What do you notice about
the amounts of carbon
dioxide and oxygen in this
diagram?
Ecosystems and Biomes - Cycles of Matter
The Nitrogen Cycle
In the nitrogen cycle, nitrogen moves from the air to the soil,
into living things, and back into the air.
Ecosystems and Biomes - Cycles of Matter
Sequencing
Sequence is the order in which a series of events occurs. As
you read, make a cycle diagram that shows the water cycle.
Write each event of the water cycle in a separate oval.
The Water Cycle
Water
evaporates.
Precipitation runs off
or becomes
groundwater.
Clouds form.
Precipitation
falls.
Ecosystems and Biomes
End of Section:
Cycles of Matter
Ecosystems and Biomes
Biogeography
Biogeography is the study of where organisms live.
From the Greek words:
Bio = life Geo = earth Graph = description
Biogeographers also try to figure out why they live there
and how they got there.
One factor that affects how species are spread out on the
Earth is Continental Drift —the movement of the
continents on top of large continental plates of rock.
Ecosystems and Biomes
Continental Drift
225 million years ago = all continents were joined
together in one large land mass called Pangea.
180-200 million years ago = Pangea broke into two
large land masses known as Laurasia and
Gondwanaland
135 million years ago = Laurasia and Gondwanaland
begin to break apart into the seven continents seen
today. They continue to drift apart every year.
Ecosystems and Biomes - Biogeography
Continental Drift
One factor that has affected how species are distributed is
the motion of Earth’s continents.
Ecosystems and Biomes - Biogeography
Continental Drift Activity
Click the Active Art button to open a browser window and
access Active Art about continental drift.
Ecosystems and Biomes
Maps like this one (by Alfred Wegener, 1915) support
the idea that the continents were once connected. They
show how identical fossils of certain plants and animal
that have been found on two sides of an ocean could
have gotten there when the continents were joined.
Ecosystems and Biomes
Dispersal
Dispersal —the movement of organisms from one place to
another. It is caused by:
Wind —disperses light weight organisms such as
seeds, spores, tiny insects or spiders
Water —disperses organisms that float such as
coconuts, leaves or animals floating on them
Other living things —many things are carried by other
living things to new places—either
accidentally or intentionally
Ecosystems and Biomes - Biogeography
Limits to Dispersal
The typical weather pattern in an area over a long period of
time is the area’s climate.
Ecosystems and Biomes
Limits to Dispersal
Three factors limit dispersal.
Physical barriers —water, mountains and deserts
can be hard to cross.
Competition —if one species out-compete
another, the other must move somewhere
else to survive.
Climate —only certain species can survive in certain
climates. This limits where they can disperse
to. Places with similar climates have species
that occupy similar niches.
Ecosystems and Biomes - Biogeography
Relating Cause and Effect
As you read, identify three causes of dispersal. Write the
information in a graphic organizer like the one below.
Causes
Wind
Effect
Water
Living things,
including humans
Dispersal of
species
Ecosystems and Biomes
Ecosystems and Biomes
End of Section:
Biogeography
Ecosystems and Biomes
Biomes
Biome —a group of land ecosystems with similar
climates and organisms.
Biomes are determined by their climate: meaning their
and precipitation amounts and temperature.
There are six major biomes in the world.
rainforest
deciduous forest
desert
boreal forest
grassland
tundra
Ecosystems and Biomes
Land Biomes and their Climates
Biome
Rainforest
Deserts
Grasslands
Deciduous
forest
Boreal
forest
Tundra
Ave. Yearly Rainfall
200-450 cm
less than 25 cm
25-75 cm
75-125 cm
35-75 cm
less than 25 cm
Ave. Yearly Temp.
25oC to 28oC
.
24oC to 40oC
.
0oC to 25oC
.
6oC to 28oC
.
-10oC to 14oC
-25oC to 4oC
.
.
Ecosystems and Biomes
Rainforest
Biome Map
Deciduous Forest
Boreal Forest
Grasslands
Desert
Tundra
Ecosystems and Biomes - Biomes
Rain Forest Biomes: Two Types
Tropical rain forests are wet, warm biomes located near
the equator. They support more than ½ of all plant and
animal species on the Earth.
Ecosystems and Biomes
Tropical Rainforests
Characteristics:
Warm all year with at least 200 cm of rain/year
Trees do not lose their leaves, creating a
dense canopy that supports much of the animal
life
Ecosystems and Biomes - Biomes
Rain Forest Biomes
Temperate rain forests receive 300 cm of rain and have
moderate temperatures. They are located in northeast U.S.
Huge cedars, redwoods and firs grow there.
Ecosystems and Biomes - Biomes
Desert Biomes
A desert is an area that receives less than 25 cm of rain per
year. Not all deserts are hot. Some are hot in the day and
cold at night (Sahara, Africa). Others are cold all the time
(Gobi, Mongolia).
Ecosystems and Biomes - Biomes
Grassland Biomes
A grassland is an area that is populated mostly by grasses
and other nonwoody plants. Grasslands close to the
equator are called savannas. They have shrubs and trees
along with grass. Most have fertile soil and grow good
crops.
Ecosystems and Biomes - Biomes
Deciduous Forest Biomes
Many of the trees in the deciduous forest are deciduous
trees, which shed their leaves and grow new ones each
year. A deciduous forest receives at least 50 cm of
precipitation each year. Temperatures vary greatly through
the year.
Ecosystems and Biomes - Biomes
Deciduous Forests
Click the Video button to watch a movie
about deciduous forests.
Ecosystems and Biomes - Biomes
Boreal Forest Biomes
Most of the trees in the boreal forest are coniferous trees,
trees that produce their seeds in cones and have leaves
shaped like needles. Winters in the boreal forest are cold
and very snowy, but summers are warm and rainy enough
to melt all the snow. This biome is also know as the Taiga.
Ecosystems and Biomes - Biomes
Tundra
The tundra is an extremely cold and dry biome. Most of the
soil in the tundra is permafrost, which is frozen all year.
Winters are long and cold with almost no daylight.
Summers are short and cool with 24 hrs. of daylight.
Ecosystems and Biomes - Biomes
Mountains and Ice
Some areas of land are not part of any major biome. These
areas include mountain ranges and land that is covered
with thick sheets of ice.
Ecosystems and Biomes - Biomes
Earth’s Biomes Activity
Click the Active Art button to open a browser window and
access Active Art about Earth’s biomes.
Ecosystems and Biomes - Biomes
Biome Climates
An ecologist collected climate
data from two locations. The
graph shows the monthly
average temperatures in the
two locations. The total yearly
precipitation in Location A is
250 cm. In Location B, the total
yearly precipitation is 14 cm.
Ecosystems and Biomes - Biomes
Biome Climates
Reading Graphs:
What variable is plotted on
the horizontal axis? On the
vertical axis?
Month is plotted on the
horizontal axis; temperature
is plotted on the vertical
axis.
Ecosystems and Biomes - Biomes
Biome Climates
Interpreting Data:
Look over the graph. How
would you describe the
temperature over the course
of a year in Location A? In
Location B?
Location A temperatures are
steady; Location B
temperatures fluctuate.
Ecosystems and Biomes - Biomes
Biome Climates
Drawing Conclusions:
Given the precipitation and
temperature data for these
locations, in which biome
would you expect each to be
located? Explain your
answers.
Location A: tropical rain
forest
Location B: desert
Ecosystems and Biomes - Biomes
Biome Climates
Predicting:
What would you expect a
temperature graph for your
biome to look like? Draw a
temperature graph for the
biome in which you live.
Answers will vary but should
reflect whether local climate
is hot or cold, seasonal or
steady.
Ecosystems and Biomes - Biomes
Comparing and Contrasting
As you read, compare and contrast the different biomes by
completing a table like the one below.
Characteristic
Temperature
Tropical
Rain
Forest
Warm all
year
Tundra
Temperate
Rain
Forest
Desert
Grassland
Deciduous
Forest
Boreal
Forest
Cold all
year
Cool
winters,
warm in
summer
Usually hot
with great
daily
extremes
Temps
vary
throughout
the year
Warm in
summer,
cold in
winter
Warm to cool
in summer,
cold in winter
Dry all year
Mostly dry
with a wet
season
Moderate
rainfall
Abundant
rain and
snow
Gamble’s
quail
Grasses
Red fox
Lynx
Precipitation
Wet all year
Dry all year
Rather wet
all year
Typical
organisms
Orangutan
Mosses
Mule deer
Ecosystems and Biomes
End of Section:
Biomes
Ecosystems and Biomes
Aquatic Ecosystems
Water covers 75% of Earth’s surface. There are two
basic types of aquatic ecosystems:
Freshwater
Marine (saltwater)
Ecosystems and Biomes
Freshwater Ecosystems
Freshwater ecosystems can be divided
into two major groups:
Running water ecosystems —streams
and rivers.
Still water ecosystems —lakes and
ponds.
Ecosystems and Biomes
Running Water Ecosystems
The amount of dissolved oxygen
determines what organisms live in
these ecosystems.
Fast-moving streams or rivers
are usually cool and therefore
have a lot of dissolved oxygen.
Little plankton is available so
dead leaves and insect larva are
important sources of food.
Fish such as trout are common.
Fast-moving stream
Ecosystems and Biomes
Running Water Ecosystems
In slow-moving streams or
rivers, plankton is the base of
the food-chain. Catfish and
bass are common.
Slow-moving stream
Ecosystems and Biomes
Still Water Ecosystems
Lakes and ponds make-up the still-water biomes.
Algae and plankton are abundant and support the
other animal life.
Ecosystems and Biomes - Aquatic Ecosystems
Marine Ecosystems
The ocean is home to a number of different ecosystems.
Factors such as water temperature and the amount of
sunlight determine what types of organisms can live in each
zone.
Ecosystems and Biomes - Aquatic Ecosystems
Open Ocean Zone—
Surface receives most
sunlight: tuna, whales,
algae.
Deep Zone —little light
passes: giant squid,
glow in the dark animals
Marine Ecosystems
Neritic Zone – Area extending
to the end of the continental
shelf. Large schools of fish,
algae, coral reef habitats
Intertidal zone --Area
between high-tide line
and low-tide line.
Barnacles, sea stars,
crabs, clams etc.
Ecosystems and Biomes - Aquatic Ecosystems
Outlining
As you read, make an outline
about the different types of
aquatic ecosystems. Use the
red headings for the main
ideas and the blue headings
for the supporting ideas.
Aquatic Ecosystems
I. Freshwater Ecosystems
A. Streams and Rivers
B. Ponds and Lakes
II. Marine Ecosystems
A. Intertidal Zone
B. Neritic Zone
C. Open Ocean
Ecosystems and Biomes
End of Section:
Aquatic
Ecosystems
Ecosystems and Biomes
Graphic Organizer
Free nitrogen is
present in air.
Bacteria release
some free
nitrogen back into
the air.
Decomposers
break down
wastes and
remains of
organisms.
Nitrogen Cycle
Bacteria in root
nodules fix free
nitrogen into
compounds.
Consumers obtain
nitrogen by eating
plants.