Compare two responses on the same criteria, weigh what each gains and risks, then make a recommendation with one stated limit. A one-sided answer cannot be marked as a comparison.
This lesson is part of environmental management. The impact evidence you compare against comes from explaining environmental impacts with evidence.
How do I set up the comparison?
Write the criteria in a row: cost, effect, time and limit. Fill each response against each criterion, leaving blanks where data is missing.
Then write one sentence per criterion with both responses inside it.
Worked example: an eroding riverbank
This is an original case. A riverbank at a village loses 0.8 m of soil each year. Two responses are supplied.
| Criterion | Planting native trees | Concrete wall |
|---|---|---|
| Cost | RM15 000 | RM120 000 |
| Effect on erosion | Reduces loss to 0.3 m a year after 4 years | Stops loss at the wall |
| Time to work | 4 years | Immediate |
| Limit | Fails if a flood comes before roots form | Erosion may shift to the next bank |
Work out the saving: 120 000 − 15 000 = RM105 000 less for trees. Loss avoided by trees is 0.8 − 0.3 = 0.5 m a year, which is 0.5 ÷ 0.8 = 62.5% of the current loss.
A comparison: “Trees cost RM105 000 less than the wall, whereas the wall works immediately and trees take 4 years to cut the loss by 62.5%.”
A recommendation: “Trees suit a village with a small budget and time to wait. The data does not say how often floods occur, so if floods are common, the wall may be safer.”
The mistake that loses marks
The weak answer writes “The wall is best because it stops erosion” and never mentions trees. It names one effect and skips cost, time and limit.
| Weak | Strong |
|---|---|
| The wall is best. | The wall stops erosion at once, but costs RM105 000 more and may move the problem downstream. |
| Trees are natural. | Trees cut loss by 62.5% after 4 years at RM15 000. |
The strong version gives figures for both options.
How do I conclude fairly?
State your choice, the deciding criterion and one limit. The decider depends on the stated need: a tight budget favours trees, urgency favours the wall.
Finish with what the data leaves out. Here, it does not say how often floods happen. The graph evidence and fair-comparison lab gives a layout for writing this.
Check yourself
Two ways to cut litter in a park: bins and signs cost RM6 000 and cut litter by 20%; a weekly cleaning team costs RM30 000 a year and removes all visible litter. Compare them and choose for a park with a RM10 000 budget.
Answer
The cleaning team costs RM24 000 more than bins and signs (30 000 − 6 000). It removes all visible litter, whereas bins and signs cut litter by 20%.
With a budget of RM10 000, only bins and signs fit, so they are the affordable choice. The data does not show whether litter returns after signs are placed, so the long-term effect is uncertain.
What to study next
Next, read interpreting fieldwork data, or try the chapter practice set. For a teacher to check your recommendations, see online one-to-one Geography tuition.