1. QCOBASS
The Freshwater Stream habitat

2. The Freshwater Stream habitat
Station 1 : Fast Running Water
Station 2 : Slow Running Water

3. Abiotic factors Physical factors Chemical factors Light intensity
Temperature
Current speed
Chemical factors

4. Light intensity Physical factors
Light intensity in different regions of 2 stations
Physical factors

5. Temperature Physical factors
Temperature in different regions of 2 stations
Physical factors

6. Chemical factors
Physical factors

7. Current speed
Physical factors

8. Biotic Factor Station 1~Fast Running Water
Found in:
Station 1~Fast Running Water
Station 2~Slow Running Water

9. Biotic Factors Animals Mayfly nymph
Large stream snail & Reservoir snail
Damselfly nymph
Freshwater crab
Common freshwater shrimp & Long-armed shrimp
Caddisfly nymph
Blood worm
Water skater

10. Mayfly nymph Location: Under rock Number:~ Fast water: 10
Slow water:15
Adaptive Features:
~3 long tail filaments
~lateral abdominal feathery gills
Biotic factor

11. Damselfly nymph Location: Under rock Number:~ Fast water: 0
Slow water: 2
Adaptive features:
~carnivore, easy to catch
Biotic factor

12. Caddisfly larva Location: Under Rock Number:~ Fast water: 15
Slow water:13
Adaptive features:
~live in case made of sand with hooked by its terminal claspers
Biotic factor

13. Blood Worm Location: Under Rock/ in bottom sediments Number:~
Fast water: 7
Slow water:10
Adaptive features:
~blood gills
~red in colour
Biotic factor

14. Water Skater Location: On water surface Number:~ Fast water: 0
Slow water: 5
Adaptive features:
~long, thin legs
~hair on legs
~thin, flattened body
Biotic factor

15. Large stream snail & Reservoir snail
Location:
Under Rock
Number:~
Fast water: 5
Slow water: 9
Adaptive features:
~have operculum
~get chemical to make
operculum
Biotic factor

16. Common freshwater shrimp & Long armed shrimp
Location:
On bottom
Number:~
Fast water: 0
Slow water: 3
Adaptive features:
~white, creamy pink or grey brown in colour
~more than 3 pairs of legs
~flattened body
Biotic factor

17. Freshwater crab Location: On bottom Number:~ Fast water: 0
Slow water: 1
Adaptive features:
~have abdomen greatly reduced
~males have a narrow abdomen with the first pair of appendages modified into a penis
~females have a broad abdomen under which the egg-mass is carried at breeding time
Biotic factor

18. Mosquito fish Location: Free swimming Number:~ Fast water: 12
Slow water: 35
Adaptive features:

19. Guppy Location: Free swimming Number:~ Fast water: 7 Slow water: 13
Adaptive features:
~female is drab olive-brown in colour
~male show a tremendous diversity in colour
Biotic factor

20. Goby Location: On water bottom Number:~ Fast water: 0 Slow water:4
Adaptive features:
~the pelvic fins are united into an oval disc which serves as a sucker
~mouth is large for attacking

21. Loach Location: On bottom Number:~ Fast water: 8 Slow water: 15
Adaptive features:
~elongated and compressed body
~3 pairs of barbels
Biotic factor

22. Plant
Algae
Taro
Spirodela polyrhiza schleid

23. Algae Type: Algae At any one time, a particular species of alga
may be very abundant, forming
an algal “bloom”

24. Taro
Type: Waterside
These plants grow at the side of the water or else are rooted in the shallow water at the edge, but have all or most of their foliage protruding aerially.

25. Spirodela Polyrhiza Schleid
Type:
Floating freely on water
These plants are not
associated with the sea bed
at all and have roots dangling
in the water.

26. Hong Kong Newt
Goby
4o consumer
Crab
Guppy
3o consumer
2o consumer
Water skater
Damselfly nymph
Mosquito fish
Blood worm
Mayfly nymph
Large stream snail
Caddisfly larva
Shrimp
loach
1o consumer
Detritus
Phytoplanton
Algae
Producer

27. Hong Kong newt Location : on the of river Behavior : nocturnal habit
Characteristic:
orange red pot on the ventral side

28. Thanks to our tutors:
~Mr. Wai
~Mr. Kan
and all the technicians