1. ( major
autotrophic community )
(Biotic
community)

2. -
-
-
-

3. (biodiversity)
:
3

4. 1. (genetic
diversity)
2. (species
diversity)
3.
(ecosystem diversity)

5. (
species diversity index )
( Simson’s index )
D = N ( N –
N ( n -
D =
N =
n =

6. Shannon Wiener index
H = - s
i=1 Pi ln Pi
H =
Pi =
S =

8. dominance
species
-
-
-
-

9. ( ecotone )
( edge

10. Changes in Ecosystems:
Ecological Succession

11. Definition:
• Natural, gradual changes in the types of
species that live in an area; can be
primary or secondary
• The gradual replacement of one plant
community by another through natural
processes over time

12. (community succession)
(sere)
(
climax community )

13. Climax Community
• A stable group of plants and animals that
is the end result of the succession process
• Does not always mean big trees
– Grasses in prairies
– Cacti in deserts

15. 1.
primary succession

16. Primary Succession
• Begins in a place without any soil
– Sides of volcanoes
– Landslides
– Flooding
• Starts with the arrival of living things such
as lichens that do not need soil to survive
• Called PIONEER SPECIES

17. xerosere
crustose lichen
foliose lichen
fructicose lichen
herbs
shrub
tree

18. Succession

19. pioneer stage
floating stage
submerged
vegetation stage
emerging
vegetating stage
marsh temporary pond
stage
pond succession

23. As the lake
becomes smaller
and smaller, it
may not be able
to provide enough
oxygen or food for
some fish But this
happens so slowly
that they have
plenty of time to
move on to other
lakes, if the lake ishttp www kidfish bc ca o

24. interactive usask ca/.../forest_succession.html

25. secondary succesion)

26. Secondary Succession
• Begins in a place that already has soil and
was once the home of living organisms
• Occurs faster and has different pioneer
species than primary succession
• Example: after forest fires

27. Succession

29. -
protozoa
succession