Biodiversity Under Threat Flashcards
What is the definition of ecosystem biodiversity?
The number and variety of organisms in a given area and has 3 components, species diversity, habitat diversity and genetic diversity.
What are the main threats facing rainforests?
Climate Change, Acid Rain ad invasion by non-native species.
Why are rainforests so fragile?
They have incredibly high biodiversity, but the loss of an ecological niche can affect the entire web.
What are the other concerns facing rainforests?
Biomass loss reduces capacity for sequestration.
Nutrients in biomass are lost due to deforestation.
Deforestation reduces organic matter input.
Loss of canopy due to deforestation results in more leaching and overland flow.
What is an example of climate change affecting rainforests?
Decreased rainfall = decreased humidity so plants that have adapted to survive on high humidity die.
How is resource extraction an issue facing rainforests?
Gold mining in the Amazon is ‘open pit’ rather than shaft mining, resulting in pits over 3km wide.
How is resource extraction an issue facing rainforests?
Gold mining in the Amazon is ‘open pit’ rather than shaft mining, resulting in pits over 3km wide.
What are the main indirect threats facing rainforests?
Demographic - increased housing requirements in Manaus, plus with increased population comes heavier demand on resources and subsistence farming.
Scientific advancement - Amazon a source of lithium + cadnium - required for Tesla & Hyundai batteries.
Economic Growth/Demand - de Barros sold off logging permits for financial gain.
Where are coral reefs located?
Between 30N and 30S with <30m deep water and must have Zooanthellae present to provide oxygen.
What is the main risk facing coral reefs?
Warmer and more acidic seas as a result of climate change.
Surface pH has increased by 0.1 since the Industrial Revolution - already becoming too acidic for delicate corals.
What is the main chemical that corals rely on for growth that there is not enough of currently?
Calcium carbonate saturation.
What are secondary/indirect threats facing coral reefs?
SE Asian reefs suffer from overfishing and destructive fishing practices (cyanide and dynamite released).
Demographic - increased burning of fossil fuels results in increased acidification.
Why are coral reefs so important?
They support 1/4 of marine life despite taking up 0.1% of seabed.
Their vertical growth creates natural habitats for a large share of biodiversity.
They support valuable fish stocks.
How can coral reefs recover from their current degradation?
If water temperature and acidification return to normal and algae can grow again.
What is super coral?
Lab-engineered coral which is currently in development that has higher resistance to temp and acidity - can completely integrate with normal coral and increase herd immunity. This is known as assisted evolution.