11.6 - Factors affecting Biodiversity

Question 1

What human influence is there on biodiversity?

Answer 1

To create space for housing, industry and farming to supply an increasing population…

• Deforestation and logging - provide wood for building and fuel, also to create real estate space.
• Agriculture - increasing amount of land is farmed, large amounts of land are cleared for monoculture (cultivation of single crop in an area)
• Climate change - due to the release of greenhouse gases causing global temperature rises
• Other forms of pollution from industry and agriculture causes chemical pollution of waterways. Improper disposal of waste & packaging causes littering.

Question 2

What are ways in which deforestation affects biodiversity?

Answer 2

• Directly reduces number of trees - reduction in number of animal species as their habitat is destroyed
• If a specific tree type is felled, species diversity is reduced.
• Animals forced to migrate to ensure survival – increases biodiversity of neighbouring areas

Question 3

How does monoculture affect biodiversity?

Answer 3

• Farms specialise in one species of crop over large acres of land
• Lowers plant biodiversity (low species richenss)
• Unlikely that many animal species can be supported by one crop, results in low overall biodiversity
• E.g. large pail oil plantations leads to deforestation, leads to habitat loss for critically endangered species (e.g. rhino)

Question 4

What is the effect of climate change (global warming) on biodiversity?

Answer 4

• Polar ice cap melting → to extinction of plant and animal species (habitat loss)
• Increasing global temperatures ⇒ temperate plant and animal species to live further north
• Higher temperatures/lower rainfall, results in plant species (mainly xerophytes) becoming dominant. The loss of non-drought resistant plants ⇒ to loss of animal species that depend on them as food source
• Insect cycles and populations will change - adapt to climate change. Insects are plant pollinators, if range of an insect changes it could affect the plants it pollinates – causing extinction.
• Insects carry plant & animal pathogens - tropical insects spread, disease could spread to poles.
• Climate change is slow = species may adapt, biodiversity may not be lost as some species migrate as well.