This deep dive covers Global Warming and Biodiversity within Biodiversity and Human Impacts for GCSE Biology. Topic 5: Biodiversity and Human Impacts on Ecosystems It is section 5 of 16 in this topic. Use this deep dive to connect the idea to the wider topic before moving on to questions and flashcards.
🌡️ Global Warming and Biodiversity
Deforestation and burning fossil fuels increase the concentration of greenhouse gases — mainly CO₂ and methane — in the atmosphere. These gases trap outgoing infrared radiation from Earth's surface, causing the planet to warm. This is the greenhouse effect.
The consequences for biodiversity include:
- Habitat loss — rising sea levels flood coastal habitats; melting ice destroys polar ecosystems
- Species migration — species shift their ranges toward the poles or to higher altitudes as temperatures rise; those that cannot migrate fast enough face extinction
- Disrupted food webs — if one species in a food web is disrupted by climate change (e.g., a plant flowering earlier, a bird arriving late from migration), the knock-on effects spread through the entire community
- Food production changes — altered rainfall and temperature patterns affect crop yields, putting pressure on humans to farm more land, further reducing natural habitats
- Ocean acidification — oceans absorb excess CO₂, making them more acidic; this damages coral reefs and shell-forming organisms, devastating marine biodiversity
Practice questions for Biodiversity and Human Impacts
What is the best definition of biodiversity?
Explain why deforestation leads to a reduction in biodiversity.
Quick recall flashcards
What is biodiversity?
The variety of all different species of organisms on Earth, or within a particular ecosystem.
Includes the range of different habitats and genetic variation within species.
What is eutrophication and what causes it?
Eutrophication is when excess nutrients (from fertiliser or sewage run-off) enter water.
This causes rapid algae growth, blocking sunlight to underwater plants.
When algae die and decompose, oxygen is used up, killing aquatic organisms.