Brainlag PlusWhy biodiversity matters, how pollution, eutrophication, land use, deforestation and peat burning reduce it, global warming, and the percentages and graphs used to measure the change.
Biodiversity under pressure
Biodiversity is the variety of all the species in an ecosystem or on Earth.
High biodiversity makes an ecosystem more stable, because species rely less on any one other species.
A growing human population uses more land and resources and makes more waste:
- Water: sewage, fertiliser and toxic chemicals.
- Air: smoke and acidic gases.
- Land: landfill and toxic chemicals; building, quarrying and farming.
- Deforestation (for cattle, rice and biofuel crops) and burning peat release carbon dioxide and destroy habitats.
Carbon dioxide and methane add to global warming, which shifts where species can live and changes migration.
Protecting biodiversity: breeding programmes, protecting rare habitats, hedgerows and field margins, less deforestation, recycling, peat-free compost.
Some species only survive in clean conditions (lichens in clean air, mayfly nymphs in clean water). Counting them is a cheap way to monitor pollution.
The rest of this lesson and its 14 practice questions are in Plus.
Screen 1 of 4, free to read.
- 14 exam-style questions, marked as you go, each with a worked solution
- Anything you get wrong is saved to your flashcards