tropical rainforests Flashcards
what are the three forest layers
emergent
canopy
undergrowth
what is the annotation for the emergent layer
(clue: very tall)
comprises of very tall trees that can grow up to 80m to reach for sunlight
what is the annotation for the canopy layer
(clue: continuous)
the trees form a continuous layer, blocking out sunlight
what is the annotation for the undergrowth layer
(clue: very little sunlight)
the plants here receive very little sunlight, and are hence shorter. lianas and epiphytes are also present here
what are lianas
they are thick woody vines that twine up trees
found mainly in the canopy and undergrowth layer
what are epiphytes
plants that perch themselves on trees
found mainly in canopy and undergrowth layer
what are buttress roots
large roots that are usually found on large tall trees
they grow 1-5m above ground
what are shallow roots
roots that are mostly found in the topsoil/top layer of the soil
why are shallow roots okay in rainforests
there is high rainfall in rainforests throughout the year
water is available all year round
hence, no need for roots that grow deep underground for water
what is the use of drip tips in leaves?
allows water to run off easily
this prevents the growth of fungi and bacteria
what is the use of waxy/leathery/hairy leaves
prevent loss of moisture through transpiration
temperature is high in rainforests, so the more water, the better for leaves
what is the use of broad leaves
capture more sunlight for photosynthesis
vegetation in rainforests is very dense
what are the three reasons tropical rainforests are important
they are carbon sinks (and also generate oxygen)
they ensure a clean water supply
the habitat to flora and fauna, and indigenous people
how do tropical rainforests help with climate change
they absorb carbon dioxide and generate oxygen
reducing the greenhouse effect
and hence helping climate change
how do tropical rainforests ensure a clean water supply
the soil help to trap impurities in the water before it flows into water sources
where are tropical rainforests located
between the tropic of cancer and tropic of capricorn
what are the four causes of deforestation
agricultural activities
commercial logging
mining
urbanisation/growth of settlements
what are agricultural activities
agricultural activities is the growing of crops and raising of animals to provide food
why do agricultural activities cause deforestation
agricultural activities (cattle ranching and crop cultivation both require large tracts of land to be cleared
this increases the rate of deforestation
what is commercial logging
the cutting down of trees for timber
what is mining
it is the clearing of forests to establish mines and construct roads
why does urbanisation cause deforestation
(include negative effects of roads)
land is cleared to make space for infrastructure and roads
roads have even more negative effects, such as providing access to previously inaccessible areas, promoting logging, mining and other rainforest damaging activities
they also attract settlements to develop and expand
what causes the deforestation of mangroves
mangroves are seen as smelly and unproductive, and hence are cleared to make room for agricultural land, settlements and infrastructure
they are also over harvested for wood, pulp charcoal and animal fodder
what is the MAIN cause of deforestation
the increasing demand/consumption of food and resources all around the world
