3.1.2.2 Tropical Rainforests Flashcards
What is the temperature like in tropical rainforests?
temp = high and constant throughout the year due to sun overhead most of the time
What is the rainfall in tropical rainforests like?
- rainfall = high due to global atmospheric circulation causing an area of low pressure to form, the rising air creates clouds and triggers heavy rain, 2000mm of rainfall per yr
- rainfall varies throughout the year, with distinct wet season lasting 6 months due to period of intense rainfall when the equatorial low pressure area is directly overhead
How many mm of rainfall are there per yr?
2000mm
What climates do TRF’s thrive in?
warm and wet/equatorial climate
What temperature do TRF’s experience throughout the year?
experiencing high temps of approx. 28 degrees C throughout the year
What is the soil quality of TRF’s?
infertile
Where are most nutrients found in the soil in a TRF?
Most nutrients are found at the surface, where dead leaves decompose in hot and humid conditions - humus layer of soil
What % of nutrients from plants are found in the humus layer?
80% of nutrients from plants found in this layer
How does leaching affect soil quality?
- Heavy rainfall can quickly dissolve and carry the nutrients away – known as leaching
- It leaves behind an infertile, iron-rich (browny-red) soil known aslatosol
What stores are nutrients found in, in the TRF?
- The biomass – living vegetation and animals
- The litter – dead wood and leaves and animal remains
What do warm, humid conditions cause in the TRF?
Warm, humid conditions cause litter to decompose very quickly
What does the little rain that reaches the RF floor do?
washes away the nutrients
What specific plants are nutrients stored in?
Nutrients are stored in the trees
What are the layers of a TRF?
- Forest Floor/Shrub Layer
- Under Canopy
- Canopy
- Emergents
What % of sunlight reaches the forest floor/shrub layer?
Less than 2% of sunlight
Describe the climate conditions in the forest floor/shrub layer of a TRF:
- Little grows except plants adapted to low light
- High humidity
Describe the decomposition that takes place on the forest floor/shrub layer of a TRF:
- On the floor is a thin layer of fallen leaves, seeds, fruits and branches that vey quickly decompose
- Only a thin layer of decaying organic matter is found, unlike in temperate deciduous forests
Describe the trees in the under canopy of a TRF:
- Relatively open and containsyoung trees (20m) and leafy herbaceous plants that tolerate low light
- Many popular house plants from this layer
- Only along rivers, roadways and in only in tree fall cut areas is sunlight sufficient to allow growth to become thick and impenetrable
What is the approximate height of trees in the under canopy in a TRF?
20m
What % of light reaches the under canopy in a TRF?
Receives 2-15% of sunlight that falls on canopy
Describe the climate conditions of the under canopy in a TRF:
- Dark place
- Lower temps
Describe the trees in the canopy layer: of a TRF
Broad, irregular crowns of these trees form a tight, continuous canopy
What is the approximate height of trees in the canopy layer of a TRF?
60-90 ft
What are branches in the canopy layer of a TRF covered with?
Branches often densely covered with plants (epiphytes) and tied together with vines (lianas)
What % of organisms in the RF is the canopy layer home to and what are they seeking?
Home to 90% of organisms found in rainforest – many seeking brighter light in the tree tops
Describe the trees in the emergent layer of a TRF:
Giant trees above dense canopy – have huge mushroom shaped crowns
How tall can trees in the emergents layer in a TRF grow?
Up to 50m in height
Describe the climate conditions in the emergent layer in a TRF:
- get most sunlight – have to endure high temps
- Low humidity
- Strong winds
Adaptations:
actions taken to adjust to natural events such as climate change, to reduce potential damage and limit the impacts
Name all the plant adaptations for plants in a TRF:
- Buttress roots
- Stilt roots
- Red leaves
- Leaf angling
- Drip tips
- Epiphytes (ivy)
How do buttress roots help plants adapt to a TRF?
- rainforest soils are very thin and therefore shallow roots are needed to soak up nutrients in these thin soils
- since trees in the rainforest grow very tall (many 30m + tall in the canopy layer) massive buttress roots form to give these roots extra stability
How do stilt roots help plants adapt to a TRF?
similar to buttress roots, these provide tall RF trees with support as they are anchored in the shallow RF soils
How do red leaves help plants adapt to a TRF?
- young RF plant saplings may have these tp give them protection from the sunlight whilst their internal organs for photosynthesis are still developing
- they act as a sunscreen by reflecting red light whilst the leaf is still young
How do lianas (vines) help plants adapt to a TRF?
- these plants have their roots in the ground and use other trees to climb up th RF canopy to maximise the sunlight they receive
- many start life in the canopy before sending roots down to the ground
How does leaf angling help plants adapt to a TRF?
leaves are often arranged at different angles so that a plant avoids shading its own leaves - important in RF’s where competition for sunlight is intense
How do drip tips help plants adapt to a TRF?
- leaves often have a waxy surface with painted tips at the end to enable excess water to run off easily
- important because this prevents the growth of algae, which if able to grow would block out any sunlight and reduce plants ability to photosynthesise
How do epiphytes help plants adapt to a TRF?
- these plants live on the surface of other plants, mostly tree trunks and branches
- this allows them to make the most of the sunlight in the canopy layer
How is a poisoned art frog adapted to the TRF?
the poison dart frog is brightly coloured to deter predators
How are toucans and parrots adapted to the TRF?
toucans and parrots have strong beaks for cracking hard nuts
How are chameleons adapted to the TRF?
chameleons have thick, leathery foot pads to protects from heat
Where are sloths found?
Tropical Rainforest e.g. Amazon, Brazil
Biodiversity:
the variety of plant and animal life in the world or in a particular habitat - a high level of which is usually considered to be important and desirable
Deforestation:
the chopping down and removal of trees to clear an area of forest
For every one mahogany tree cut down how many fall down by accident?
For every one mahogany tree cut down 28 fall down by accident
How many species go extinct every day?
137 species go extinct every single day
What % of medicine comes from TRF’s?
around 25% of all medicines come from rainforest plants
How much of the worlds plants and animals do TRF’s contain?
TRF’s contain half of the worlds plants and animals
How do indigenous people live with the TRF?
indigenous people live in harmony with the RF
What are TRF’s known as?
known as “the lungs of the world”
What % of the worlds O2 comes from TRF’s?
28% of the world’s O2 comes from RF’s
What sorts of resources do TRF’s provide?
TRF trees provide valuable resources e.g. hardwood, nuts, rubber, fruits etc.
What % of the world’s fresh water comes from the Amazon Basin?
20% of the world’s fresh water comes from the Amazon Basin
How do TRF’s prevent climate change?
RF’s absorb and store CO2 - reducing greenhouse gas effect
Name all the things TRF’s are valuable for:
- medicine
- biodiversity
- people
- climate
- resources
- water
- climate change
