Living world - tropical rainforests Flashcards
Where are tropical rainforest found?
a few degrees either side of the equator between the Tropics of Cancer and Capricorn
What is the rainforest climate like?
- equatorial climate
- high temperatures throughout the year (avg 27C) because sun is mostly overhead
- lots of rainfall (>2000mm per year) because global atmospheric circulation causes an area of low pressure over the equator creating clouds and heavy rain
- variation in rainfall caused by months where low pressure area moves directly overhead causing a distinct wet season
what are rainforest soils known as?
latosols
what are rainforest soils like?
- old, deep, iron-rich and red
- very infertile because nutrients are rapidly lost through leaching (minerals lost in solution) due to rain
- rapid nutrient cycling here
what are the 3 major nutrient stores for nutrient cycling?
- soil
- biomass
- litter
what are the important things about nutrient cycling in tropical rainforests?
- majority of nutrients are stored in biomass - lush vegetation
- few nutrients stored as biomass - rapid decomposition by fungi and bacteria
- few nutrients stored in soil - rapid uptake by plants + lots of leaching
how biodiverse are tropical rainforests?
- very - they only cover 7% of earth’s surface yet are home to 50% of all living organisms
- consists of plants, micro-organisms, fungi, insects, birds and animals
what are the layers of a tropical rainforest? (top to bottom)
- emergent layer - 35-50m - trees here get the most light but are also the most exposed to the wind
- canopy layer - 20-35m - 90% of all organisms live here. Some super productive trees with wide crowns for more SA, others waiting to take advantage of the next light space
- understory layer - 10-20m - only receives 2-15% of all sunlight. Lots of young leafy plants waiting to grow when they get light + ferns + woody plants
- forest floor - 0-10m - <2% of all sunlight - plants have to be well adapted here. Thin layer of fallen leaves, seeds, fruit and decomposing matter
how are plants adapted for the tropical rainforest?
- epiphytes - plants which live on trees high up in the air that get their nutrients from the air and water - make the most of sunlight
- lianas - woody vines growing from the ground but having leaves and flowering in the canopy
- tree trunks are thin and straight to allow trees to grow quickly
- bark is thin because trees don’t have to retain water - its already s humid
- drip tips - allow water to run off leaves quickly without damaging/breaking the leaf
- buttress roots - large roots have ridges to create large SA and help spread the weight of massive trees
what are adaptations?
actions taken to adjust to natural events such as climate change to reduce potential damage and limit the impacts
how are animals adapted to the rainforest?
- camouflage - creatures can blend into the surroundings and hide from potential predators/prey - eg. sloth
- mimicry - pretend to be something else - eg. grasshoppers looking and behaving like stinging wasps
- limiting diets - only eating food that other animals can’t access - eg. toucans and fruit
- habitat adaptation - having adaptations to make the creature well suited to that particular part of the rainforest - eg. spider monkeys have long, strong limbs to move through the canopy
what is biodiversity?
the variety of plant and animal life in the world or in a articular habitat, a high level of which is usually considered important and desirable
how is biodiversity under threat in rainforests?
- deforestation - rainforest trees -> pasture, commercial plantations or settlements
- water pollution - mining poisons rivers reducing aquatic life and killing wildlife
- climate change - deforestation reduces evapotranspiration causing climactic drying
where is Malaysia located?
- in South-East Asia
- spread across Peninsular Malaysia and Malaysia in Borneo
- bordered by Thailand and Indonesia
- South China Sea separates 2 parts of Malaysia
what is the current rate of deforestation in Malaysia?
- one of the highest rates in the world - losing 1 football pitch every 4 minutes
- lost almost 16% of primary rainforest between 2002 and 2018
