The Living World - Tropical Rainforests Flashcards
Distribution/Location of TRFs
Found in the belt close to the equator
South America, West Africa, South-East Asia, North Australia
Climate of TRFs
High temperature - 27 degrees Celsius
High rainfall - 2,000mm per year
High Humidity
No seasonal Difference
Plants and Animals in the TRF
Highest level of biodiversity
Huge range of habitats available
Home to over Half the worlds plants and animals
Water in TRFs
Distinct wet season
High rainfall lasting several months
Excess water = local rivers flood
Water soaks into soil = leaching
Soils in TRFs
Not very fertile
Nutrients are in the upper top soil
Trees and plants have shallow roots
Intense leaching removes nutrients from soil
People in TRFs
Traditional tribes live in the rainforest in harmony with the natural environment
Exploitation of rainforest for commercial gain - deforestation
Harmful to rainforest - reduces biodiversity and destroys habitats
Different plant layers in a tropical rainforest
Emergents
Canopy
Under canopy
Forest Floor
Species in each layer of the rainforest
Emergents - bats
Canopy - Birds
Under canopy - Mammals - sloths/monkeys
Forest Floor - Deer
Nutrient cycling process
- Nutrients in soil are taken up by tree roots
- They are stored in the leaf (biomass) of the tree
- When the leaves die they fall to the forest floor (Litter)
- Moist + warm conditions cause the leaf to decompose - returns nutrients to the soil
How do people rely on plants and animals in the tropical rainforest
Animals help the nutrient cycle and keep the TRF healthy
Plants produce 20% of Earth’s oxygen
What resources are species competing for in topical rainforests
Space
Sunlight
Nutrients & water
3 adaptations plants have made in order to cope in TRFs
Lianas
Drip tips
Buttress roots
Lianas
Woody vines that climb up trees to reach the sunlight
Grown in the CANOPY
Buttress Roots
Large roots which create a large SA to support trees
Absorb more nutrients from soil
FOREST FLOOR
Drip Tips
Leave that have pointy tips
Water can run off leaves quickly without damaging or breaking them
EMERGENTS
Two animals that have adapted to the physical conditions of TRFs
Poison Dart Frog
Three-toed sloth
How has the poison dart frog adapted to the physical conditions
When they eat poisonous insects, they absorb the toxins in their mucus
Feet have extra-strong suction cups to climb and hold slippery branches
How has the three-toed sloth adapted to the physical conditions of the TRFs
Extra vertebrae to be able to turn neck 270* to check for predators above/below
Can swim in floods
Grown green algae in fur to camouflage
Socio-economic value of rainforest
Resources
Tribes
Energy
Employment
Socio-economic value of resources from the rainforest
Medicine - 120 prescription drugs are derived from rainforest plants
Food - fruit, nuts, spices, wild meat and fish
Minerals - gold, silver, iron ore
Fuel source - energy
What employment opportunities do TRFs offer
Tour guides for tourists
Primary Sector - Mining, logging, farming, construction
How do tribes value the TRF
Well being and survival depend on a balanced ecosystem
How is energy generated in TRFs
High rainfall = hydroelectric power - dams and resovoirs
Helps LICs to supply demand
Environmental value of TRFs
Water
Biodiversity
Climate
Climate CHange
Soil Erosion
Explain the Environmental value of the Rainforest
Water - vital source of fresh water
Biodiversity - 50% of the world’s animals and plants exist in TRFs
Climate - 28% of the worlds xylem in from TRFs
Climate change - Carbon sink
Soil Erosion - Roots bind to tropical soils, reducing risk of soil erosion - reduce risk of flooding
What are the threats facing Biodiversity
- Slash and burn agriculture
- Mining and subsequent pollution of water supplies from toxic metals
- Unsustainable timber harvesting
- Development of roads and settlements
If biodiversity declines, what issues does this lead to?
- Indigenous tribes are unable to survive - have to abandon their traditional lifestyle
- Plant & animal species become extinct
- Important medical plants may be extinct
Why do rates of deforestation vary
Different national governments have different policies, whether they exploit TRF for resources of conserve the delicate ecology of the TRF
Case study of a TRF
The Amazon Rainforest
Location of The Amazon Rainforest
South America
Covers Columbia, Peru, Brazil, Bolivia, Venezuela
Which direction does the amazon river flow
West to East
The source starts in the west and the mouth is in the east
Causes of Deforestation in the Amazon
Subsistence Farming
Commercial Famring
Logging
Road Building
Illegal trade in wildlife
Mineral Extraction.
Settlement & population growth
Energy Development
Subsistence farming
Farming of crops is used to maintain the farmer + families leaving little for scale or trade
3 million landless people in Brazil
Commercial Farming
Faring of crops and cattle for sales in markets
Logging
Logging is cutting trees to sell wood to companies
In the Amazon only 3% of deforestation comes from logging
Road Building
Construction of Transamazon highway allows access to remote areas
Illegal trade in wildlife
Poaching and hunting
Upsets the natural balance ofd the rainforest ecosystem
Mineral extraction
Mining means trees are cleared and top soil is removed - damages whole ecosystem
The largest iron ore mine in the world is at Caracas, it is worked by 3,000 people 24 hours a day
Settlements and population growth
As the industry develops, it brings economic oppurtunities, people migrate to the rainforest
Increase demand for homes = deforestation
Energy Development
High rainfall creates ideal conditions for hydroelectric power
Belo Monte Dam will block a river tributary flooding of more than 40,500 HC and displacing 15,000 people
Issues with commercial farming
Land can only sustain cattle and crops for a short period of time before soil loses nutrients
Land is cleared more regularly to ensure the source of income is stable
Local Impact of deforestation
Water cycle is disrupted by deforestation
Less moisture is returned to atmosphere, fewer clouds and drier climate
Water is a cooling system - without it the climate gets warmer
Regional impact of deforestation
Biodiversity loss
Deforestation = loss of habitat
Endangered animals and threat of extinction
National impact of deforestation
Decline of Indigenous tribes
Threatens homes, food supply and traditional way of life
Knowledge of culture is lost
Global impact of deforestation
Climate change
CO2 is released back into the atmosphere
Carbon sink to carbon source 🙁
Small scale forestry strategies to reducing deforestation
Selective Logging - reduces number of valuable trees cut down - takes 30 years
Agroforestry - planting trees and crops together to save resources
Replanting - saving seeds from original trees and replanting them - takes time
Global scale strategy to manage deforestation
2006 International Tropical Timber Agreement
+ Prevents people illegally cutting down valuable wood/trees
- Often goes unnoticed because remote parts of the rainforest are unmonitored
Management strategy - Debt reduction
+ Encourages countries to invest in sustainable management of TRF by making it economically neutral to do so
- Money might not be used correctly, reliant on HIC investments
Management Strategy - Ecotourism
+ Uses the ecosystem to attract tourists, Monet generated is invested in conservation projects
Management strategy - Education add conservation
+ Teaches people the threats on the rainforest and how to protect these vulnerable areas
- May not get enough volunteers or donations
