Threats to Biodiversity - Environmental Science Section 1EG Spring 2025 CO

The primary threat to biodiversity and consequently human welfare is human population growth and the resource consumption associated with it.
Essential resources for human survival and growth are being extracted unsustainably.

Three main proximate threats to biodiversity:
- Habitat Loss: Deforestation, urban sprawl, and environmental modifications lead to the destruction of ecosystems where species live.
- Overharvesting: Extracting more resources from nature than can be replenished. This includes overfishing and unsustainable logging practices.
- Introduced Species: Non-native species brought into new environments can disrupt local ecosystems and outcompete native species.
These threats are largely direct consequences of human population pressure and resource use amplified by increased mobility and trade.

Climate Change: Although not yet a major factor in extinction rates, the impact of human-induced climate change is predicted to increase in significance. This is due to human demands for energy and reliance on fossil fuels.
Toxic Pollution: While significant, the effects of pollution are generally targeted and not on the same scale as other threats.

Recent historical data show dramatic increases in atmospheric carbon dioxide levels.
Current levels are unprecedented and contribute to climate change, impacting biodiversity significantly.

Human technology modifies environments to accommodate us, often resulting in habitat loss for other species.
Critical habitats include forests, coral reefs, grasslands, and rivers; the elimination of any of these can lead to extinction of the resident species.
Example: The exceptional biodiversity in Sumatra, which is home to critically endangered species like orangutans and Sumatran tigers, has significantly diminished due to habitat destruction.
- Forest Loss in Sumatra and Borneo: Both islands have experienced massive deforestation, with ongoing destruction for timber extraction and palm oil plantations.
- Statistics: From 2000 to 2005, an estimated 3.1% of global forest cover was lost, primarily in tropical regions, driven by timber extraction and plantations. This loss also represents a high risk of species extinction in these areas.