20.2 Habitat Destruction

Biodiversity refers to the number of different species that live in a specific area. It is a measure of the variety of life forms present in an ecosystem. Areas with high biodiversity support many different species, while areas with low biodiversity have fewer species.

High biodiversity indicates a healthy ecosystem with:

• Many different species coexisting
• Complex food webs and interactions
• Greater ecosystem stability and resilience

Habitats such as tropical rainforests and coral reefs have exceptionally high biodiversity due to favorable environmental conditions that support numerous species.

Habitat destruction occurs when natural environments are damaged or removed, threatening the species that depend on them. The main reasons for habitat destruction include:

Housing Development

• Growing human populations require more space for residential areas
• Natural habitats are cleared to build houses, towns, and cities

Crop Plant Production

• Land is cleared to grow crops for food or commercial sale
• Forests and grasslands are converted into agricultural fields
• This often involves removing native vegetation

Livestock Production

• Areas are cleared to create grazing land for cattle, sheep, and other livestock
• Natural habitats are replaced with pastures

Large-scale industrial activities cause significant habitat damage:

Mining Operations

• Extraction of minerals like copper, gold, and coal requires massive excavation
• Open pit mines dramatically alter landscapes
• Example: Huge open pit copper mines in Chile significantly change the terrain and destroy existing habitats

Timber Extraction

• Logging companies cut down large numbers of trees for wood products
• This removes entire forest ecosystems

Marine Pollution

• Collecting live corals from coral reefs damages the entire habitat
• Pollution from chemicals, plastics, and oil spills harms aquatic ecosystems
• Coral reefs are particularly vulnerable as they support hundreds of species

Freshwater Pollution

• Contamination of rivers, lakes, and streams affects aquatic life
• Agricultural runoff and industrial waste damage freshwater habitats