Natural Hazards
Explain why an earthquake can cause more damage in one area than another, even if both areas experience the same earthquake.
Damage depends on factors such as building quality, population density and preparedness. Areas with poorly constructed buildings are more likely to experience collapse, while better-prepared areas can reduce deaths and damage.
A farmer notices that crop yields have fallen even though the amount of land cultivated has stayed the same. Explain one possible reason.
Soil nutrients may have been depleted by repeated cultivation. Fertilisers can replace nutrients needed for plant growth and increase yields.
A mining company removes a large amount of soil and rock before reaching an ore deposit. What is this material called, and why must it be removed?
It is overburden. It must be removed to expose and access the mineral deposit beneath it.
A region receives plenty of rainfall but still experiences water shortages. Explain how this is possible.
Rainfall may be seasonal or unevenly distributed, and water may be lost through runoff or evaporation. The region may also lack sufficient storage and distribution infrastructure.
Explain why volcanic eruptions can sometimes be predicted more successfully than earthquakes.
Volcanoes can produce warning signs such as increased seismic activity, changes in gas emissions and swelling of the ground as magma rises. Earthquakes generally provide fewer reliable warning signs before sudden movement occurs
Explain why fertilisers can increase crop yields but may also create environmental problems.
Fertilisers supply nutrients such as nitrogen and phosphorus, promoting plant growth and increasing yields. However, excess fertiliser can be washed into rivers, causing eutrophication and reducing water quality.
A country has a large mineral deposit but decides not to mine it. Suggest two factors that could make extraction uneconomic.
The ore may have a low concentration of the valuable mineral, making extraction expensive. The deposit may also be difficult to access, requiring expensive infrastructure or deep mining.
Explain how over-abstraction of groundwater can create a long-term water supply problem.
Removing groundwater faster than it is naturally replaced lowers the water table. Wells may eventually dry up and less water becomes available for people, agriculture and ecosystems.
A coastal city is located near an active plate boundary. Analyse why the city may face several different hazards from one earthquake
Ground shaking can collapse buildings and damage infrastructure. If the earthquake occurs beneath the sea and causes vertical movement of the seabed, it may generate a tsunami. Strong shaking can also trigger landslides, while damaged electricity or gas infrastructure may cause fires. Therefore, one earthquake can produce several primary and secondary hazards
A farmer replaces traditional farming with intensive agriculture using irrigation, fertilisers and pesticides. Analyse two benefits and two environmental costs of this change.
Irrigation provides water during dry periods, while fertilisers replace soil nutrients and pesticides reduce crop damage, increasing yields and food production. However, excessive irrigation can cause waterlogging or salinisation, while pesticides may contaminate water and harm non-target organisms. The overall benefit depends on how sustainably these inputs are managed
A mining project will provide thousands of jobs but will also remove vegetation and create waste material. Evaluate whether the project should be approved
The project could provide employment, government revenue and minerals needed for industry. However, vegetation clearance can cause habitat loss, while waste can pollute soil and water. Approval could be justified if strict environmental controls, waste management and land restoration are required
A government must choose between building a large dam and developing several smaller water-storage projects. Analyse one advantage and one disadvantage of each option.
A large dam can store substantial amounts of water and may provide hydroelectric power, but it can flood large areas and disrupt river ecosystems. Smaller projects may have less environmental impact and can be distributed closer to communities, but individually they may provide less storage
A country has limited money to reduce earthquake deaths. It can either spend most of the money on earthquake prediction technology or on improving building standards. Which should it prioritise? Justify your answer
Improving building standards should generally be prioritised because earthquake prediction remains limited, whereas stronger buildings can reduce deaths whenever an earthquake occurs. Retrofitting buildings, enforcing building codes and improving construction quality directly reduce vulnerability. However, prediction and education can still complement protection by allowing people to prepare and evacuate where possible
A farming region is experiencing declining soil fertility, falling yields and increasing food demand. Compare two strategies that could improve food production without causing further environmental degradation.
Crop rotation can maintain soil fertility by varying crops and, where appropriate, including nitrogen-fixing crops. Organic matter such as compost can improve soil structure and nutrient availability. These approaches can maintain productivity while reducing dependence on excessive fertiliser use. However, their effectiveness depends on local soils, climate and farming practices
A country is heavily dependent on exporting minerals. Analyse why increasing mineral extraction may improve its economy in the short term but create problems in the long term.
Mining can generate export earnings, employment, tax revenue and foreign investment. However, mineral resources are finite and prices can fluctuate, making the economy vulnerable to changes in global demand. Environmental damage from mining can also create long-term costs. Recycling, diversification and restoration can help make mineral use more sustainable.
A rapidly growing city is experiencing increasing water demand. Evaluate two strategies the government could use to reduce pressure on freshwater supplies.
Improving water efficiency through leak reduction, efficient appliances and public awareness can reduce demand without requiring a new water source. Reusing treated wastewater can provide water for irrigation or some urban uses and reduce demand for freshwater. However, wastewater treatment requires investment, while conservation measures depend on public cooperation. A combination is likely to be more effective than relying on one strategy.
A densely populated coastal region is located near a destructive plate boundary. The government has enough money to introduce only three major measures to reduce future disaster losses. Using your knowledge of hazard prediction, preparation, protection and emergency response, decide which three measures should receive priority. Justify your decision and explain why the other possible approaches are less important.
Priority should be given to earthquake-resistant buildings, effective evacuation/emergency planning and hazard monitoring/early-warning systems where possible. Strong buildings reduce deaths when ground shaking occurs and provide protection regardless of whether an earthquake can be predicted. Emergency planning, drills and clearly identified evacuation routes improve people's responses and reduce confusion. Monitoring can provide useful warnings for some hazards and improve preparedness, although exact earthquake prediction remains difficult. Simply relying on prediction would therefore be less effective because an accurate prediction may not be possible. The best strategy is to reduce vulnerability before the event while ensuring people can respond quickly when a hazard occurs.
A country needs to increase food production because its population is growing rapidly. One proposal is to expand farmland into forests. Another is to intensify production on existing farmland using irrigation, fertilisers and pesticides. Evaluate both options and recommend the approach that is more sustainable in the long term.
Expanding farmland may increase the area available for food production, but clearing forests causes habitat loss, reduces biodiversity and can increase soil erosion. It may also release stored carbon. Intensification can produce higher yields from existing land, reducing the need for further clearance. However, excessive irrigation can cause waterlogging or salinisation, while fertilisers and pesticides can cause pollution. Therefore, sustainable intensification is generally the better option, provided inputs are carefully managed. Techniques such as efficient irrigation, appropriate fertiliser application, integrated pest management and soil conservation can maintain yields while reducing environmental damage
A mineral-rich region must decide whether to allow a new large-scale mine. The mine would provide employment, export income and minerals for industry, but it would require vegetation clearance, generate waste and could contaminate nearby water supplies. Evaluate whether the economic benefits justify the environmental costs. Your answer should consider both short- and long-term consequences and reach a justified conclusion.
The mine could provide significant short-term economic benefits through employment, export earnings, government revenue and the supply of raw materials. These benefits may improve infrastructure and living standards if the revenue is managed effectively. However, mining can remove vegetation, disturb habitats and produce waste that may contaminate soil and water. Water pollution can affect ecosystems, agriculture and human health, creating costs that continue after extraction ends. The project could be justified if environmental management is strictly enforced, including safe waste disposal, pollution monitoring, water protection and restoration of the land after mining. Therefore, the mine should not automatically be rejected, but approval should depend on whether its economic benefits can be achieved without unacceptable long-term environmental damage.
A semi-arid country is facing increasing water demand from households, agriculture and industry, while rainfall is becoming less reliable. The government is considering building a dam, expanding irrigation, recycling wastewater and introducing water-conservation measures. Evaluate these options and recommend the combination that would provide the most sustainable water supply.
A large dam can provide reliable storage and help manage seasonal shortages, but it may flood land, displace communities and alter river ecosystems. Expanding irrigation can increase agricultural production, but inefficient irrigation may waste water and cause waterlogging or salinisation. Wastewater recycling can provide an additional supply without depending entirely on rainfall, although treatment infrastructure is expensive. Water conservation is often highly sustainable because reducing demand means less water needs to be extracted in the first place. Therefore, the most sustainable approach would be a combination of conservation, efficient irrigation and wastewater recycling, with additional storage used where necessary. Relying on a dam alone would increase supply but would not address the underlying problem of rising demand.