Tropical Rainforest Flashcards
(15 cards)
1
Q
A
2
Q
Features of a tropical rainforest?
A
- Tall, mostly evergreen trees (due to low seasonality)
- High rainfall
- High light levels -> increased primary productivity = more food energy to rich food web
- High temps
- Low seasonality
3
Q
What allows plants to grow all year, providing constant reliable food sources?
A
- High light levels
- High amounts of rainfall
- High temps
4
Q
What is the importance of rainforests?
A
- High biodiversity
- Resources
- Carbon sequestration
- Hydrological cycle
- Soil maintenance
5
Q
What are the benefits of high biodiversity in the rainforest?
A
- Estimated half of all terrestrial species live there and rainforests cover 10% of earths surface
- Increased chance of finding species useful to humans eg: new food species, medicine, biomimetics
6
Q
What resources can come from the rainforest?
A
- Timber -> house construction, tools
- Fibres -> cotton
- Resin, oil, wax -> rubber, palm oil
- Food -> chocolate from cacao, bushmeat
- Medicines -> Mexican wild yams produce diosgenin used for arthritis medication
7
Q
What is carbon sequestration?
A
- Plants absorb CO2 for photosynthesis
- Stored in woody tissues (if plant has any) and builds up a store of carbon
- reduces atmospheric CO2
8
Q
How is the rainforest important to the hydrological cycle?
A
- Important for downwind rainfall
- Over half rainfall in Amazon rainforest comes from transpiration elsewhere in the forest instead of evaporation from seawater
9
Q
How does the rainforest maintain soil?
A
- Warm, moist conditions = fast DOM decay = quick reabsorption of nutrients
- Because of this soils are shallow
- Vegetation cover protects from rain and roots bind soil together
10
Q
What are the threats to the rainforests?
A
- Deforestation
- Agricultural expansion
- Cattle grazing
- Mineral extraction
- Reservoirs
- Global climate change
- Exploitation of individual species
- Tourism
11
Q
What causes agricultural expansion?
A
- Farmers clear rainforests for agriculture due to fertile soils
- Continuous farming depletes biomass and soil fertility = more deforestation
- Habitats removed and soil quality reduced
12
Q
A
13
Q
What are the effects of deforestation?
A
- Disrupts ecosystem due to habitat loss for species
- Habitat fragmentation -> isolated populations and increased edge effects
14
Q
What is the reason for deforestation?
A
- For fuel, timber -> construction, furniture
- Valuable hardwoods (teak, mahogany) targeted = long lasting damage
- Space for settlements and agriculture
15
Q
How does cattle grazing threaten the rainforest?
A
- Trees cleared for grazing land for cattle -> overgrazing, soil compaction
- Trees cleared for soy farms for soy based feeds
- All cause deforestation, decreased soil quality, habitat destruction
