O Level Geography Resources Sustainability Quiz

Answer Key - Resources Sustainability Quiz

1. Definition of Sustainable Development

• Development that meets the needs of the present without compromising the ability of future generations to meet their own needs. (2 marks)

2. Anthropocentric vs Ecocentric

• Anthropocentric: Nature is a resource to be used for human benefit.
• Ecocentric: Nature has intrinsic value regardless of its use to humans. (2 marks)

3. Intensification and Soil Degradation

• Over-use of chemical fertilizers can lead to soil acidification or salinization, reducing soil fertility over time. (2 marks)

4. Trend Description (Hypothetical Fig 1)

• Overall trend: Increasing/Decreasing/Fluctuating.
• Evidence: Cite start value (e.g., 10m tonnes in 1990) and end value (e.g., 15m tonnes in 2020).
• Rate: Mention if the increase was rapid or gradual. (3 marks)

5. HYV Seeds and Fertilizers

• HYV seeds are bred for high productivity but are "nutrient-hungry".
• They deplete soil nutrients faster than traditional varieties.
• Therefore, chemical fertilizers are needed to maintain high yields. (3 marks)

6. Process of Eutrophication

• Nutrient runoff (nitrates/phosphates) enters water body $\rightarrow$ Algal bloom (rapid growth of algae) $\rightarrow$ Algae block sunlight $\rightarrow$ Submerged plants die $\rightarrow$ Bacteria decompose plants and use up oxygen $\rightarrow$ Hypoxia/Anoxia $\rightarrow$ Fish and other aquatic life die. (4 marks)

7. Clean Water and Labor Productivity

• Reliable clean water reduces waterborne diseases (e.g., cholera, dysentery).
• Fewer sick days for workers $\rightarrow$ consistent labor supply.
• Better health/nutrition $\rightarrow$ higher physical and mental capacity for work. (4 marks)

8. Reducing Runoff

• Use of buffer strips (vegetation along water edges) to trap nutrients.
• Precision farming/controlled application of fertilizers. (2 marks)

9. Population Growth and Water Management

• Higher population $\rightarrow$ increased demand for domestic, industrial, and agricultural water.
• Pressure on existing aquifers/rivers leads to depletion.
• Necessitates sustainable management (e.g., desalination, recycling) to prevent water stress. (4 marks)

10. Non-renewable Resources

• Example 1: Fossil fuels (Coal/Oil) - take millions of years to form; used faster than they regenerate.
• Example 2: Minerals (Iron/Copper) - finite deposits in the crust; once extracted, they cannot be replaced. (4 marks)

11. Four National Taps (Singapore)

• Local catchment: Collecting rainwater via drains/reservoirs.
• Imported water: Agreements with Malaysia.
• NEWater: High-grade reclaimed water (recycling).
• Desalination: Converting seawater to fresh water.
• Together, they diversify sources and reduce reliance on a single source, ensuring resilience. (6 marks)

12. Bioaccumulation

• Pesticides (e.g., DDT) are non-biodegradable.
• Absorbed by primary producers (plankton/plants).
• Eaten by primary consumers (small fish) $\rightarrow$ concentration increases.
• Eaten by apex predators (large fish/birds) $\rightarrow$ highest concentration.
• Leads to toxicity or reproductive failure in top predators. (6 marks)

13. Extreme Weather and Food Insecurity

• Droughts: Reduce crop yields, kill livestock, dry up irrigation sources.
• Floods: Wash away topsoil, destroy harvests, cause crop diseases.
• Unpredictable patterns: Disrupt planting/harvesting cycles.
• Result: Local food shortages and price spikes. (6 marks)

14. Traditional vs Intensive Farming

• Traditional: Lower yields, less chemical use, lower environmental pollution, but higher risk of famine.
• Intensive: High yields, high chemical use, causes eutrophication/soil degradation, but ensures food supply for growing populations. (6 marks)

15. Renewable Energy in Developing Countries

• High initial capital cost for infrastructure (solar farms/wind turbines).
• Lack of technical expertise for maintenance.
• Reliance on existing cheap fossil fuel infrastructure.
• Political instability or lack of government subsidies. (6 marks)

16. Urban Farming

• Reduces "food miles" (transport distance) $\rightarrow$ lower carbon footprint.
• Uses vertical space (hydroponics/aeroponics) $\rightarrow$ land efficiency.
• Provides fresh produce to urban populations, reducing reliance on imports. (6 marks)

17. Technology and Food Security (Evaluation)

• Agree: Precision farming, GMOs (pest resistance), vertical farming increase yields and resilience.
• Disagree: Technology is expensive (inequity); doesn't solve political conflict or poverty; can cause environmental harm.
• Conclusion: Technology is a critical tool but must be paired with fair distribution and sustainable policies. (8 marks)

18. Climate Change and Water Scarcity (Evaluation)

• Agree: Altered rainfall patterns $\rightarrow$ prolonged droughts; melting glaciers $\rightarrow$ loss of long-term water storage.
• Disagree: Over-extraction for agriculture; poor governance/infrastructure; population growth.
• Conclusion: Climate change exacerbates scarcity, but human mismanagement is often the primary driver. (8 marks)

19. Economic Benefits vs Environmental Costs (Evaluation)

• Benefits: Lower food prices, higher national income, employment, food security.
• Costs: Loss of biodiversity, water pollution (eutrophication), soil degradation, greenhouse gas emissions.
• Conclusion: Short-term economic gains are high, but long-term environmental costs may undermine the very productivity the system relies on. (8 marks)

20. Eutrophication as Most Serious Impact (Evaluation)

• Agree: Creates "dead zones," destroys fisheries, affects drinking water quality, hard to reverse once systemic.
• Disagree: Soil erosion/desertification is more permanent; pesticide bioaccumulation affects entire ecosystems; loss of biodiversity is irreversible.
• Conclusion: Eutrophication is severe and widespread, but "most serious" depends on whether one values water quality over soil fertility or biodiversity. (8 marks)