tropical rainforests Flashcards
3 facts about tropical rain forest
occupy 7% of worlds surface
they contain many useful resources
help the fight against global warming
where are rainforests mainly situated
south east asia
maazon basin in brasil
central africa
which is the largest tropical rain froest
amazon
what are the 2 main characteristics of the tropical rainforest
climate and vegetation
describe the climate of the rainforest
warm and wet as they are close or on the equator
average temperature is 26 degrees
annual rainfall above 2500m
describe the vegitation
rich cover, tall trees
describe the soil
1 thin and poor 2 nutrients are rapidly recycled 3 litter decomposes quickly 4 nutrients are washed away before they join the soil so they are infertile 4 nutrients are stored in tree trunks
how is the rainforest interdependent
the climate soils vegetation and animals interact
1 nutrients fall to ground when plants and animals die
2 the nutirnts become part of the soil plants take up the nutirents disolved in the soil
what are indiginous people
natives
are they interdependent
yes but human activity can upset the balance
how much biodiversity is there in the rainforest
more than 2/3 of world plants and 1/2 of known animals are found in the rain forest
what are the effects of humans on bio diversity
they exploit resourses reducing biodiversity endangering species some becoming extinct
what is the effect of loss of biodiversity
decline in ecosystym productivity
if soil in the rainforest is poor how do plants cope
1 rapid recycling of nutrients
2 absorb sunlight for photosynthesis
3 warm humid climate is ideal for plant growth
4 plants adapt to compete for sunlight and nutrients
how have plants adapted
leaf canopy catches rain stops it hitting the ground hard and eroding the soil
they have shallow roots to take water and nutrients from the litter
waxy leaves allow water to run off
leaves are flexible to move to the sun to maximise photosyntheis
what are the 4 layers of the tropical rainforest
continuous canopy
under canopy
dense shrub layer
shrub layer
what do plants adjust to
the physical conditions particulaly the available sunlight
where is most and least sunlight available and what is the result of little sunlight
most - top of the trees
least- forest floor
result little photosynthesis
if only a little photosynthesis takes place where do plants get their food
from soil or parasitic plants attaching to host trees to share food and water
there are many trees in the rainforest what does this impact on
a lot of competition for food
give examples of how animals are adapted to get food
parots have sharp beaks for hard nuts some animals are camoflaged to avoid being eaten
what is scale of deforestation
estimated 1/2 of worlds tropical rainforests have been cleared at a rate of 1 hector per second
where has brazilian rainforests clearance been
to south of amazon
what have indiginous tribes used rainforests for
harvest fruit, cut wood for fuel and timber, discover cures
what methods of clearance did indienous people use
slash and burn or subsistence farming
what is the impact of slash and burn or subsistence farming - clearance methods used by indiginous people
little lasting damage, when soil in one area is exhausted they move else wheremso forest degenerates - so human use doesnt always cause deforestation
what is forest degradation
ecosystems change in a negative way and the supply of resources decline
name 2 ways brazilian rainforests are being exploited
using resources- timber water minerals
clearing the forest to make way for livestock and crops
what are the main exploiting activities in the brazilian rainforests
1 logging - for furniture or fuel
2 mine extraction - rainforest cleared to extract gold
3 energy development - dams built for hydroelectric power so large areas of rain forest flooded
4 illegal trade in wildlife - endangering species and upsetting ecosystem
what activities are causing forests to be cleared
1 subsistence farming - moving to another area when area is exhausted
2 commercial cattle farming- cleared to make way for rearing livestock
3commercial farming- forest cleared to make way for crops
4 road building - roads need to bring in equipment and transport products
5 settlement and population growth - the workers for other activities need homes and serves so forest is cleared for settlements
what are the global impacts of deforestation
global warming and loss of diversity
what are the local impacts of global warming
decline of indiginous tribes soil erosion river polution conflicts local climate change
how does deforestation cause global warming
tress felled so they cant absorb CO2 from atmosphere
fire is often used for clearing so carbon returns to the atmosphere
how does deforestation cause loss of biodiversity
individual species become endangered or extinct so reduces biodiversity
as species disappear do do possible cures for disease
what is the local impact of climate change (5)
1 deforestation disrupts water cycle
2 top soil is removed by rain so nothing can grow
3 mercury is used to separate gold it enters and pollutes rivers poisons fish and people
4 tribes are forced to leave they find it hard to adjust to change - they take with them the knowledge of the rainforest
5 conflicts arise betwen indiginous and loggers
what goods come from rain forst
cocoa sugar bananas spices vanilla
why is it in the interest of global health care to protect the rainforests
there are plants used to treat diseases
what are 3 levels of sustainable action that could be taken to protect the rainforest
1 international agreements to protect resources
2 debt reduction most countries with rainforests are LICs and have large debts HIC could run debt for 2 2 nature swaps
3 conservation and education
what should governments do to protect rainforests
create protected areas
stop abuse by developers
make environmental studies part of the curriculum
why dont governments take action to protect the rainforest
slows economic development
what can be done at a local level for sustainability
1 respect environment and culture of locals 2 use traditional skills and knowledge 3 give people control over their land 4 generate income from locals 5 use appropriate technology
what can be done for stainability at a local level in areas of logging
selective logging - fell only fully grown trees
stop illegal logging
replant and collect seeds
