Cambridge IGCSE·Co-ordinated Sciences 0654·Biology
Human Influences On Ecosystems
Key knowledge — Human Influences On Ecosystems
Key facts & rules
- Deforestation: reduces biodiversity, increases CO₂ (burning), increases soil erosion, affects water cycle.
- Greenhouse gases: CO₂, methane, water vapour. Absorb and re-emit infrared radiation → warm Earth.
- Eutrophication: excess fertiliser → algal bloom → algae die → bacteria decompose → bacteria use O₂ → aquatic animals die.
- Pesticides: may accumulate along food chain (bioaccumulation/biomagnification) — highest concentration in top predator.
- Conservation strategies: nature reserves, captive breeding, seed banks, international agreements.
- Sustainable development: meeting current needs without compromising future generations' ability to meet theirs.
IGCSE Biology — Human influences on ecosystems
341 Cambridge IGCSE 0654 biology past paper questions on human influences on ecosystems, organised by subtopic. Pick a subtopic to start practising.
About human influences on ecosystems on IGCSE 0654
Pollution, deforestation, the greenhouse effect, conservation and the human impact on biodiversity.