Deforestation: land demand and ecological effects
| English | Français |
|---|---|
| biofuel/ˌbaɪəʊˈfjuːəl/ | biocarburant |
| deforestation/diːˌfɒrɪˈsteɪʃn/ | déforestation |
What would explain this observation?
- Replacing a forest with a crop can increase one useful product while removing many habitats. Food or fuel output is only one part of the decision.
- Start with a prediction. State the quantities or features you would compare, then decide what evidence could distinguish two explanations.
Build the model
- The specification identifies tropical forest clearance for cattle, rice cultivation and biofuel 生物燃料 crops. Forest removal destroys habitat and can reduce biodiversity. Burning cleared material releases carbon dioxide; later decay can also release carbon. Fewer trees can reduce photosynthetic uptake compared with the original forest, although replacement plants also photosynthesise.
- deforestation 森林砍伐: Removal of forest for another land use; biofuel: Fuel produced from biological material.
Which evaluation includes both a benefit and a biological cost?
The result depends on the replacement system, what happens to the wood and the time interval. A claim that every biofuel has no emissions ignores land-use change and production. Evaluate food, income and energy benefits alongside habitat, carbon and other environmental consequences using the supplied evidence.
Match each technical term to its precise meaning.
Use the definitions to distinguish related quantities and processes.
Choose evidence that can test it
- The result depends on the replacement system, what happens to the wood and the time interval. A claim that every biofuel has no emissions ignores land-use change and production. Evaluate food, income and energy benefits alongside habitat, carbon and other environmental consequences using the supplied evidence.
- Compare a fictional land-use proposal with retained-forest and alternative-site options. Use area, production and stated carbon-transfer records separately, avoiding double counting carbon released from the same material. Explain the biological mechanism rather than writing only deforestation is bad.
Which two habits make the investigation or model in this case more defensible?
Compare a fictional land-use proposal with retained-forest and alternative-site options. Use area, production and stated carbon-transfer records separately, avoiding double counting carbon released from the same material. Explain the biological mechanism rather than writing only deforestation is bad.
Work from known quantities
- State the known values and their units. Choose the relation because its assumptions fit this case, then rearrange before substitution.
- Known: a supplied 150-hectare region retains 105 hectares of forest after clearance. Cleared area = 45 hectares, or 30%. This describes that region; it is not a current global deforestation statistic. A biodiversity conclusion also needs information about which habitats and species were affected.
A supplied region has 240 hectares of forest and retains 168. Find the cleared percentage. Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.
A supplied region has 240 hectares of forest and retains 168. Find the cleared percentage.
The result is 30 %. Known: a supplied 150-hectare region retains 105 hectares of forest after clearance. Cleared area = 45 hectares, or 30%. This describes that region; it is not a current global deforestation statistic. A biodiversity conclusion also needs information about which habitats and species were affected.
Check the conclusion and its limits
- Trees do not store carbon only while alive: dead wood and soil can also be stores. Carbon dioxide release and reduced future uptake are different terms. A new crop’s photosynthesis does not automatically replace all original habitat or carbon storage.
- Return to the original observation. Explain what the result supports, which conditions it assumes, and one way to test a competing explanation.
Growing a biofuel crop guarantees no environmental cost from land clearance. This claim is false: Trees do not store carbon only while alive: dead wood and soil can also be stores. Carbon dioxide release and reduced future uptake are different terms. A new crop’s photosynthesis does not automatically replace all original habitat or carbon storage.
Deforestation: land demand and ecological effects: The result depends on the replacement system, what happens to the wood and the time interval. A claim that every biofuel has no emissions ignores land-use change and production. Evaluate food, income and energy benefits alongside habitat, carbon and other environmental consequences using the supplied evidence.
Growing a biofuel crop guarantees no environmental cost from land clearance.
Trees do not store carbon only while alive: dead wood and soil can also be stores. Carbon dioxide release and reduced future uptake are different terms. A new crop’s photosynthesis does not automatically replace all original habitat or carbon storage.
Removal of forest for another land use: write the technical term.
deforestation means Removal of forest for another land use.