Zusammenfassung der Ressource
Distribution
of organisms
- Organisms live in different places
because the environment changes.
- A habitat is the place where an animal lives.
- The distribution of an organism is where that
organism is found e.g in part of a playing field.
- Where an organism is found is
affected by environmental factors.
- Such as: Temperature, Amount of
light, availability of water, oxygen,
carbon dioxide and nutrients.
- An organism might be more common in one
area than another due to differences in
environmental factor between the 2 areas.
- For example, in a field you might find that daisies
are more common in the open than under trees,
as there is more light available in the open.
- There are a couple of ways to study
the distribution of organisms.
- You can: Measure how common an organism is in
2 sample areas and compare them or Study how
the distribution changes across and area.
- Quadrants are used to study the
distribution of small organisms.
- A quadrant is a square frame enclosing a known
area e.g 1m square. Used to compare how how
common an organism is in 2 sample areas by:
- 1) Place a 1m square quadrant
on the ground at random point
within the first sample area.
- E.g divide the quadrant up into a grid and
use a number generator to pick a square.
- 2) Count all the organisms
within that quadrant.
- 3) Repeat steps 1
and 2 as many
times as you can.
- 4) work out the mean number of organisms
per quadrant within the first sample area.
- 5) Repeat steps 1 - 4 in another sample area.
- 6) Finally compare the 2 means. E.g you might find 2 daisies
per m square in tthe shade and 22 in the open (a lot more).