A4.2 Conservation of biodiversity

What are the 3 levels of biodiversity?

1. Genetic

2. Species

3. Ecosystem

What does high biodiversity lead to?

Greater resilience and stability

What does low biodiversity lead to?

Low genetic diversity → inbreeding risk

What are the anthropogenic causes of extinction?

• Habitat destruction (farming, urbanisation)

• Invasive species outcompete natives

• Pollution (plastics, toxins, CO2)

• Climate change exceeds adaptive capacity

• Over-harvesting (fishing, hunting, logging)

What are the causes of ecosystem loss?

• Agriculture + deforestation

• Urbanisation

• Overexploitation (fuelwood, bushmeat, cod fishing)

• Mining and smelting → acid rain, toxic soils

• Dams and irrigation → rivers/lakes collapse

• Wetland drainage e.g. Mesopotamian marshes

• Fertiliser runoff → eutrophication

• Climate change → biome shifts e.g. forest → shrubland

What are the causes of the current biodiversity crisis?

• 75% terrestrial and 66% marine ecosystems altered

• Human population ~8 billion = driver of demand

What is the in situ conservation strategy?

Protect species in habitats (parks, reserves, rewilding)

What is the ex situ conservation strategy?

Zoos, seed banks, captive breeding and release

What is the rewilding conservation strategy?

Restore minimal-management ecosystems

What does EDGE stand for?

Evolutionarily Distinct and Globally Endangered

What is the priority of the EDGE programme?

Species with few or no relatives and high extinction risk

What is the purpose of the EDGE program?

Preserve unique branches of evolutionary history