Factors that shape an environment. Abiotic and Biotic, organisms niche, interactions between species in communities, succession (primary and secondary).

1.  Order from largest to smallest: organism,
community, biosphere, ecosystem, biome,
population.
 What is the difference between an ecosystem
and a community?
Catalyst:

2. Shaping of an
Ecosystem
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I will be able to identify what shapes an ecosystem
in regards to biotic and abiotic factors, niches, and
biological succession.

3. What shapes an ecosystem?
 Ecosystems are shaped by a combination of
biological and physical factors.
 Biological factors are living, or were once alive,
are known as biotic factors.
 Ex: birds, trees, grass, mushrooms, bacteria, etc.
 Physical, or nonliving factors are called abiotic
factors.
 Ex: temperature, wind, precipitation, rocks, soil,
water, mountains, etc.

4.  Together, biotic and abiotic factors determine
the survival and growth of an organism and
the productivity of the ecosystem in which the
organism lives.
 The area in which an organism lives is called its
habitat. The habitat includes both abiotic and
biotic factors.
What shapes an Ecosystem?

5. Alive or Not? Biotic v. Abiotic

6. Alive or Not? Biotic v. Abiotic

7. Alive or Not? Biotic v. Abiotic

8. Alive or Not? Biotic v. Abiotic

9. Alive or Not? Biotic v. Abiotic

10. Alive or Not? Biotic v. Abiotic

11. By the way, these are
Ligers…

12.  A niche is the full range of physical and
biological conditions in which an organism
lives and the way in which the organism uses
those conditions.
 Basically an organisms role, or job in its habitat!
 Maybe its niche is the organisms place in a food
web, or maybe the temperatures it needs to
survive.
 BTW; biotic and abiotic factors often determine
the number of niches in an ecosystem.
The Niche

13. The Niche

14.  Competition: when organisms of the same or
different species attempt to use an ecological
resource in the same place at the same time.
 Water, nutrients, light, food or space=resources.
 Predation: when one organism captures and
feeds on another organism.
 Symbiosis: a relationship in which two species
live closely together.
 Mutualism, Commensalism, and Parasitism.
Community Interactions

15. Examples of
community
interactions!

16.  Dominant species in a community are species that are
the most abundant or have the highest biomass. They
exert control over the abundance and distribution of
other species.
 Ex: Sugar Maples, they affect the abiotic factors (shade
and soil nutrients), which in turn, provide special habitats
for many other species.
 Keystone species are not abundant in a community.
However, they exert major control over other species in
the community.
 Ex: Sea otters, are high in the food chain and feed on sea
urchins, which feed on kelp (remember Planet Earth?)
Where the sea otters are abundant, there are few sea
urchins, and kelp forests are abundant. In contrast, when
sea otters are eaten by Orcas, sea urchins are abundant,
and kelp is rare.
Dominant and Keystone
Species

17.  Hey class! Remember when I told you that
ecosystems change, and therefore carrying capacity
changes? Well, it’s back.
 Most communities are dynamic (changing), not
stable.
 They change in response to natural and human
activities, but we’ll call them disturbances.
 Ex: volcanic eruptions, strip mining, clear-cutting a
forest, forest fires, etc.
 This causes older inhabitants to die out, and new
organisms to move in, causing further changes in
the community. This is called…..SUCCESSION.
Succession

18.  If rebuilding begins in a lifeless area where
even the soil has been removed, the process is
called primary succession.
 THE ESSENTIAL AND DOMINANT
CHARACTERISTIC OF PRIMARY
SUCCESSION IS SOIL BUILDING!
 After the ecosystem has been destroyed, the
first organisms to inhabit a barren area are
pioneer organisms.
 Lichen (algae and fungi together) and mosses are
examples.
Primary Succession

19.  Soil develops as rocks, weather, and organic
matter accumulate from the decomposed
remains of pioneer species.
 Once soil is present, pioneer organisms are
overrun by other larger organisms: grasses,
bushes, and then trees.
 The final and stable community that remains is
called the climax community.
Primary Succession Cont..

21.  Happens when a disturbance of some kind
changes an existing community without
removing the soil.
 When land is cleared and plowed for farming,
then abandoned, or a wildfire.
 Some plants have even adapted to a regular cycle
of fire and regrowth.
Secondary Succession