5)Ecological succession Flashcards
1
Q
Primary succession (basic) ?
A
- beaches
- larva flows
- sever landslips
- ponds
- bare rock
2
Q
Secondary succession (basic) ?
A
-disturbance removes species
3
Q
What determines community structure ?
A
1) Disturbances
- physical disasters ( storms , floods)
- humans and animals
- climate change
2)Competitive interactions
4
Q
Pioneer species stage?
A
- Hardy to withstand extreme variations in temperature
- establish rapidly
- have spores and seeds to disperse over long distances
- do not grow in shade
5
Q
How do pioneers help ?
A
1) build up , stabilize and enrich soil
2) alter amount of light by producing shade
6
Q
Primary succession ?
A
- Lichen = become established on a rock after a disturbance
- soil starts to form as lichens and physical weathering break down rocks
- mosses , ferns , grasses and annuals
- faunal pioneer species (mites , ants and spiders)
7
Q
Secondary succession ?
A
- Annuals (herbs and weeds)
- grasses and perennials
8
Q
Intermediate species stage ?
A
- soil can hold more water and be more fertile
- temperatures are less extreme = more shade
- grasses remain
- large herbivores and small carnivores
- snakes
9
Q
Climax community ?
A
- last semi-stable stage
- endpoint of succession
- everything is in a state of transition as anything could change
10
Q
What factors determine an endpoint ?
A
1) rainfall
2) overgrazing
3) climate change
4) draining of wetlands
5) Invasion by aliens (triffid weed and orange lantana)
