Ecological Succession and Biodiversity

The members of a species that live in a
specific ecosystem are known as a
population

Buffalo

population

Rabbit

population

Grass

population

The group of populations that live in an area and
interact together form a _____________.

community

Prairie

Community

An ecosystem includes all of the biotic (living) and
abiotic (non-living) factors.

Prairie

Community

Levels

of

Organization

Organism (Species)

The role (job) that each species has in an ecosystem is
known as its ______. This includes where the species
lives, what it eats and what it provides to the rest of
the community.

niche

Photo by Donar Reiskoffer

Photo by Snežana Trifunović

Time

Most environments are not static; they change over time.

Ecological succession is the natural, gradual change in the
types of species (community) that live in an ecosystem over
time.

1.Primary Succession

• Defined: Establishment and development of an

ecosystem in an uninhabited environment

• Starts with bare rock

1. New lifeless land is still created today. The

formation of this land is often the result of
____________ eruptions and receding
___________.

volcanic
glaciers

Pioneer Species

2. Pioneer species: First organisms to inhabit new land

– Moss and lichen (which is fungi and algae in a symbiotic

relationship) grow on bare rock

– Dead matter and crumbling rock → first layer of soil.

The Process Continues

3. Seeds grow in the new soil.
4. Small flowers & shrubs build up more
organic matter
5. Small animals and insects inhabit land

The Process Continues

6. As plants and animals die, the soil gets more
nutrients and is able to support larger plant life
7. Animals use the trees as a habitat

The Process Continues

8. Large trees take root, compete with smaller trees
9. Large animals inhabit new forests

Time

Succession ends once a climax community is established. A
climax community is a stable group of plants and animals in the
ecosystem.

Because it starts from bare rock, primary succession can take
hundreds to thousands of years to reach a climax community.

Barren rock

Lichens and mosses

(Pioneer species)

Annuals

Grasses and Ferns

(Perennials)

Shrubs and

Bushes

Softwoods
Hardwoods

Secondary Succession

• Defined: Rebuilding an ecosystem after a natural

disaster
– Includes forest fires, floods, and deforestation

Secondary Succession

• Secondary succession follows most of the same

major steps of primary succession; however, it
occurs at a much faster rate

• This is because in secondary succession, the soil

already exists, so plants can immediately start
growing

Secondary Succession

• Secondary succession usually only takes decades to

occur, and the climax community can be achieve in
as little as 50 years

Multiple Choice

In which of these places can one observe primary succession?

• tropical rain forest

• abandoned field recently

• burned forest

• recently created volcanic island

Multiple Choice

What is the correct order from oldest (happened first) to youngest (happened last) in this pond succession?

• A, B, C, D

• D, C, B, A

• B, A, D, C

• C, D, A, B

Multiple Choice

After a volcanic eruption, lava covers the land. What is the order that plants grow to repopulate the area?

• Lichens → Shrubs → Grasses → Trees

• Lichens → tree → shrubs→Grasses

• Grasses → Lichens → Shrubs → Trees

• Lichens → Grasses → Shrubs → Trees

Multiple Choice

This is an example of...

• Secondary Succession

• Primary succession

• Utter and complete destruction! RAWR!

• Climax Communities

Multiple Choice

This is an example of...

• Climax communities

• Secondary succession

• Primary succession

• Pioneer species

Multiple Choice

This is an example of...

• Climax communities

• Secondary succession

• Lichen

• Pioneer species

Multiple Choice

This is an example of...

• Primary Succession

• Secondary Succession

• Climate Community

• Pioneer Species

Multiple Choice

reaches a climax community quicker because soil is already present

• primary succession 

• secondary succession

• both types of succession

Multiple Choice

starts with bare rock followed by lichen

• primary succession 

• secondary succession

• both types of succession

Multiple Choice

a stable ecological community that has reached equilibrium

• ecological succession 

• climax community

• secondary succession

• pioneer speciles

Multiple Choice

the first organisms that appear in an ecological community

• ecological succession 

• primary succession 

• secondary succession

• pioneer speciles

Multiple Choice

succession that occurs in an area where soil is already present

• ecological succession 

• primary succession 

• secondary succession

• pioneer speciles

Multiple Choice

succession that occurs in an area with no soil

• ecological succession 

• primary succession 

• secondary succession

• pioneer speciles

Reorder

Reorder the following (1 is earliest stage)

• Bare Rock

• Lichen

• Herbs

• Shrubs

• Oaks

1

2

3

4

5

• 1
• 2
• 3
• 4
• 5

Multiple Choice

What are examples of pioneer species in a primary succession?

• Bushes and Shrubs

• Oak trees

• Mossess and Lichens 

• A rose Bush

Multiple Choice

Rocky material left behind by a retreating glacier forms what is called a moraine. When primary succession occurs the moraine, which life-forms will help create the soil by breaking down bare rock?

• Insects

• Lichens

• Grasses

• Deciduous trees