hopefully, this could help you to understand much better in this chapter..... biology is fun!!

2. 8.2 COLONISATION AND
SUCCESSION IN AN ECOSYSTEM
A community of organisms which interact
Ecosystem
with their non-living environment and
function as a unit
Biotic components are well balanced with
Dynamic Ecosystem
one another and with the abiotic
components
- Natural environment where organisms live
Habitat
-Provides basic resources og life such as food,
shelter, living space, nesting sites and mates

4. Species
A group of organisms that:
look alike and have similar characteristics
share the same roles in an ecosystem
capable of interbreeding to produce fertile offspring

5. population
A group of organisms of the same species
living in the same habitat at the same time

6. Community
- A several populations of different species
living in the same habitat of an ecosystem
-Interpendent and interact with one
another in order to survive

7. NICHE
-A niche of an organism is its role in the
ecosystem
-Niche of a population:
ranges of temperatures at which it lives
the type of food it eats
the space it occupies
-animals that undergo metamorphosis in
their cycle occupy different niches.
A tadpole lives A frog lives mainly
entirely in water on the land

9. BARE GROUND
• An environment of bare rocks and sand left
behind by a forest fire is not suitable for most
organisms.
• After the ground cools down, water re-enters
the environment. When water, air, nutrients
and sunlight are available, spores and seeds of
certain plants start to germinate and grow.

10. PIONEER SPECIES
• The first colonizers
• Special adaptations is enable to survive on dry
and nutrient-poor soil
• Hardy plants which usually have dense root
system to bind the sand particles and hold
water and humus
• Short life cycle
• When die, they remains add to the humus
content of soil

11. Successor species
• Modify the environment, eventually creating
conditions which are less favorable to themselves
• Grow bigger than pioneer species, thus reducing
the amount of sunlight that reaches them and
gradually replacing them
• Have small wind-dispensable seeds which are
able to spread and grow rapidly
• Change the structure and quality of the soil,
making it more conductive for larger plants to
grow

12. Dominant species
• Can grow faster and so they out-compete the
pioneers which grow at a slower rate
• Turn modify the environment which allows
larger trees to grow
• The larger trees out-compete the shrubs,
which are replaced by forest-floor species
which require low light intensit
(succession)

13. • Ecological success leads to a relatively stable
community which is in equilibrium with its
environment
• Example: tropical rainforest in Malaysia
• A stable community that undergoes little or
no change in its species composition

14. Colonisation
• A process whereby a species invades and
occupies a newly formed area where no
life has existed previously

15. Succession
• The gradual process through which one
community changes its environment so that it
is replaced by another community