Paper 1: Tropical Rainforest Flashcards
Describe the distribution of tropical rainforests
-Most found close to equator
-All are found between the tropics
climatic characteristics of a rainforest
-no seasonal temp diff
-high annual rainfall
-‘hot and wet’
-high humidity
Why do the rainforests have high solar insolation
-located between tropics
-sun directly overhead all year
-heats air = rises
-low pressure = rain
biomass importance in maintaining soil fertility
-leaf litter decomposes
-releases nutrients
ideal conditions for decomposition
-warm and humid
-moisture
fertile soil importance in rainforest
-allows plants to survive
-support organisms at other trophic levels
Nutrient Cycle: stores
-biomass
-soil
-litter
Nutrient Cycle: inputs
-weathering of parent rock
-rainfall
Nutrient Cycle: ouputs
-surface runoff
-leaching
Nutrient Cycle: flows
-plant uptake
-decomposition
-littering
poor nutrients is because of
-plant competition for nutrients
-nutrients stay in soil briefly
-heavy rainfall = leaching
leaching
washing out of nutrients from soul giving it low fertility
Emergent layer
-tallest tress
-emerge above canopy
-absorb best sunlight
Canopy
-densest layer
-50% of wildlife is here
-below emergent layer
undercanopy
-bare tree trunks and lianas
-younger tress grow toward canopy but not all are successful
lianas
vines that climb vegetation in a bid to reach sunlight
shrub layer
-shrubs and ferns
-plants that need less light
-sapling are here
saplings
young trees
forest floor
-dar
-damp
-layers of dead organic matter (leaf litter)
Plant adaptation: leaves waxy surface + drip tips
-shed excess rainwater quickly
-prevents mould in humid climate
Plant adaptation: flexible bases
-turn to face sun
-maximise light for photosynthesis
Plant adaptation: emergent tress are tall + fast growing
-maximise light for photosynthesis
-grow above main canopy
Plant adaptation: trees’ shallow roots
-maximise nutrient uptake
-absorb rapid decomposing leaf litter on soil
Plant adaptation: emergent trees’ wide buttress roots
-width = extra support
-as roots are shallow
Plant adaptation: lianas use trees for support
-grow quickly towards main canopy
-more light = photosynthesis
Plant adaptation: colourful fleshy fruits with seeds
-animals consume seeds
-disperse widely over rainforest
-germination
Animal adaptation: toucan’s strong beaks
-hard shells of nuts can be cracked
-curved shape = accessibility to hard to reach food
Animal adaptation: Apes have strong limbs
-strength to climb to tops of trees
-most food and sunlight here
Animal adaptation: red-eyed tree frog = long sticky tongue
-hide in canopy
-swallow insect species whole
Animal adaptation: poison dart frog is bright blue
-colour acts as a warning
-poisonous to predators
Animal adaptation: sloths can camouflage
-hide to protect themselves
-from predators
Social value of rainforests:
-medicines are derived from here (2/3 for cancer)
-indigenous tribes who depend on rainforest