Ecosystems

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Ecosystems: area identified by its dominant vegetation cover

Understanding how ecosystems work:

Requires - energy from sun, water and nutrients

Primary producers ---> Primary consumer ---> Secondary consumer ---> Tertiary consumer

Life Support Systems:

Water cycle

Green Lungs

Energy/sun

Nutrient Cycle

Green Lungs:

Forests remove CO2 from the atmosphere. This reduces global warming

Forests give out oxygen - purifying the atmosphere

More than 20% of the worlds oxygen is produced in the Amazon rainforests

Deforestation is responsible for 18 - 25% of global CO2 emissions

Nutrient Cycling:

Forests provide leaf litter which forms humus. This makes the soil more fertile for growing crops

Hydrological Cycle:

Forests protect watersheds from soil erosion and intercepts precipitation preventing flash flooding

By trapping silt forests keep water pure

Reefs and mangroves provide protection from coastal storms

Amazon rainforests store over half of Earth's rainwater

Goods:

121 prescription drugs sold come from plant derived sources

25% pharmaceuticals come from rainforests

3000 plants from rainforests are active against cancer cells

How do different people value the rainforest?

Tribes - their home (source of food/medicine), their culture/traditions

Environmentalists - valuable life support system - climate change

MEDC's - have TNC's and might want to protect to regulate cycles to not increase global warming

LEDC's - resources

Tourists - tourism, holidays - places for them to visit