Cambridge IGCSE · thinka 原创模拟试题

2024 Cambridge IGCSE Geography (0460) 模拟试题及答案详解

Thinka Nov 2024 (V3) Cambridge IGCSE-Style Mock — Geography (0460)

195 分285 分钟2024
分析模拟试题
An original Thinka practice paper modelled on the structure and difficulty of the Nov 2024 (V3) Cambridge IGCSE Geography (0460) paper. Not affiliated with or reproduced from Cambridge.

卷一 甲部 (Population and Settlement)

Answer one question from this section.
3 题目 · 32 分
题目 1 · structured
18 分
Table 1.1 shows selected population structure data for Country X (a newly industrializing country) and Country Y (a highly developed country).

Table 1.1:
- Young dependents (0-14 years): Country X = 25.0%, Country Y = 13.0%
- Economically active (15-64 years): Country X = 66.0%, Country Y = 64.0%
- Old dependents (65+ years): Country X = 9.0%, Country Y = 23.0%
- Total dependency ratio: Country X = 51.5, Country Y = 56.3

(a) Study Table 1.1.
(i) What percentage of Country Y's population is made up of young dependents?
Underline or state your choice from: 9.0% / 13.0% / 23.0% / 25.0% [1]
(ii) Compare the proportion of old dependents in Country X and Country Y. Use statistics in your answer. [2]
(iii) Describe three features of a population pyramid for a country with a low birth rate and high life expectancy, such as Country Y. [3]
(iv) Explain why birth rates are declining in many transitioning countries like Country X. [4]

(b) Many countries have unbalanced dependency ratios.
(i) Describe three problems that a country might face if it has a high young dependency ratio. [3]
(ii) Explain the strategies a country can use to cope with a rapidly aging population. [5]
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解题

(a)(i) According to Table 1.1, the percentage of young dependents in Country Y is 13.0%.
(a)(ii) Country Y has a significantly higher proportion of old dependents (23.0%) compared to Country X (9.0%). This is a difference of 14.0% points.
(a)(iii) Features of an aging country's population pyramid include a narrow base (indicating low birth rates), a wide/thick top (indicating high life expectancy/large elderly cohort), and straight or barrel-shaped sides (low death rates in middle age).
(a)(iv) Declining birth rates in transitioning economies are driven by increased urbanization, female empowerment and participation in higher education/careers, availability and social acceptance of family planning and contraception, and a shift away from subsistence agriculture where children are needed as laborers.
(b)(i) High young dependency ratios cause heavy government expenditure on primary education and school infrastructure, strain healthcare systems with pediatric care, and limit domestic savings as parents spend disposable income on immediate childcare.
(b)(ii) To manage an aging population, governments can raise the retirement age (retaining older workers in the tax base), encourage selective immigration of working-age adults, introduce pro-natalist subsidies/policies to boost birth rates, promote private pension schemes to reduce reliance on state funding, and invest in healthcare automation.

评分标准

(a)(i) 13.0% = 1 mark.
(a)(ii) 2 marks: 1 mark for comparison (higher in Y / lower in X); 1 mark for correct paired statistics (Country Y is 23% and Country X is 9%).
(a)(iii) 3 @ 1 mark: Narrow base / contracted bottom; Wide top / thick apex; Straight/barrel-shaped sides; Tall height.
(a)(iv) 4 @ 1 mark: Access to / cost of contraception; Female education / career focus; Later marriages; Cost of raising children; Low infant mortality rates (no need for 'replacement' children); Anti-natalist policies.
(b)(i) 3 @ 1 mark: Cost of schools/teachers; Strain on pediatric healthcare; Lack of immediate workforce / high dependency burden on active workers; Underinvestment in other economic sectors.
(b)(ii) 5 @ 1 mark (or development): Raise retirement age (retains taxpayers); Encourage migration of active age groups; Pro-natalist incentives (e.g., tax breaks/childcare subsidies); Increase taxes to pay for elder care; Promote private pension funding; Use of technology/care-automation.
题目 2 · open-ended
7 分
For a named country or area you have studied, explain the causes of rural-to-urban migration. You should refer to both push and pull factors.
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解题

Example Case Study: Migration from the North-East region of Brazil to São Paulo. Push factors from the rural North-East: Severe droughts in the semi-arid Sertão region lead to crop failure and water shortages. The mechanisation of large estates (latifundia) leaves subsistence farmers landless and unemployed. There is a lack of high schools and clinics. Pull factors to São Paulo: Diverse job opportunities in manufacturing and services offer higher, reliable incomes. There is better access to secondary and higher education and healthcare services. The perception of 'bright lights' and entertainment attracts younger migrants.

评分标准

Level 1 (1 to 3 marks): Simple statements identifying push and/or pull factors (e.g., no jobs in the countryside; better schools in the city). Level 2 (4 to 6 marks): Developed statements explaining push and/or pull factors (e.g., mechanisation of farming reduces the need for manual labour, leaving farm workers unemployed; cities have manufacturing industries offering formal employment and stable wages). Max 5 marks if no named or inappropriate example, or if only push or only pull factors are explained. Level 3 (7 marks): Comprehensive explanation of both push and pull factors, with at least three developed points, a named example (e.g., Brazil), and place-specific details (e.g., Sertão, São Paulo).
题目 3 · open-ended
7 分
For a named country or area you have studied, explain the causes of rural-to-urban migration. You should refer to both push and pull factors.
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解题

Example Case Study: Migration from the North-East region of Brazil to São Paulo. Push factors from the rural North-East: Severe droughts in the semi-arid Sertão region lead to crop failure and water shortages. The mechanisation of large estates (latifundia) leaves subsistence farmers landless and unemployed. There is a lack of high schools and clinics. Pull factors to São Paulo: Diverse job opportunities in manufacturing and services offer higher, reliable incomes. There is better access to secondary and higher education and healthcare services. The perception of 'bright lights' and entertainment attracts younger migrants.

评分标准

Level 1 (1 to 3 marks): Simple statements identifying push and/or pull factors (e.g., no jobs in the countryside; better schools in the city). Level 2 (4 to 6 marks): Developed statements explaining push and/or pull factors (e.g., mechanisation of farming reduces the need for manual labour, leaving farm workers unemployed; cities have manufacturing industries offering formal employment and stable wages). Max 5 marks if no named or inappropriate example, or if only push or only pull factors are explained. Level 3 (7 marks): Comprehensive explanation of both push and pull factors, with at least three developed points, a named example (e.g., Brazil), and place-specific details (e.g., Sertão, São Paulo).

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卷一 乙部 (The Natural Environment)

Answer one question from this section.
2 题目 · 25 分
题目 1 · structured
18 分
Answer this question if you choose the section on **The Natural Environment**.

Study **Fig. 3.1**, a diagram showing the cross-section of a waterfall, and **Fig. 3.2**, a diagram showing a cross-section and plan view of a river meander.

**Fig. 3.1** shows a waterfall where a layer of resistant limestone overlies a layer of weak shale. Below the falling water is a deep pool.

**Fig. 3.2** shows a meander bend with Point X on the outer bend and Point Y on the inner bend of the river channel.

(a) (i) Identify the term used to describe the deep pool formed at the base of a waterfall, as shown in Fig. 3.1.

(ii) State and describe three different processes of river erosion.

(iii) Explain how a waterfall, such as the one shown in Fig. 3.1, is formed and retreats upstream over time.

(b) (i) Using Fig. 3.2, compare the physical conditions and processes occurring at the outer bend (Point X) and the inner bend (Point Y) of a meander.

(ii) Explain how human activities in a drainage basin can increase the risk of flooding along a river valley.
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解题

(a) (i) Plunge pool.

(ii) Three processes of river erosion:
- Hydraulic action: the sheer force of the moving water loosening and washing away materials from the bed and banks.
- Abrasion (corrasion): sediment and rocks carried by the river scrape and wear away the river bed and banks.
- Attrition: rocks and stones carried by the flow collide with each other, breaking into smaller, rounder fragments.
- Solution (corrosion): weak acids in the water dissolve soluble minerals (like calcium carbonate in limestone) in the river bed and banks.

(iii) Formation and retreat of a waterfall:
- A river flows over an area where a band of hard, resistant rock (e.g., limestone) lies on top of a band of softer, less resistant rock (e.g., shale).
- The softer rock is eroded more rapidly by processes like hydraulic action and abrasion, causing undercutting.
- This undercutting creates an overhang of hard rock that is unsupported.
- A plunge pool develops at the base of the waterfall due to the force of the falling water and the swirling action of eroded rocks.
- Eventually, the overhanging hard rock collapses into the plunge pool because of gravity.
- This cycle of undercutting, overhang formation, and collapse repeats over time, causing the waterfall to migrate upstream and leaving a steep-sided gorge.

(b) (i) Comparison of Point X (outer bend) and Point Y (inner bend):
- Outer bend (Point X) has faster water velocity / higher speed of flow, whereas inner bend (Point Y) has slower water velocity / lower speed of flow.
- Outer bend is deeper, whereas inner bend is shallower.
- Erosion (such as hydraulic action or abrasion) is the dominant process at the outer bend, whereas deposition is the dominant process at the inner bend.
- A steep river cliff is formed on the outer bend, whereas a gently-sloping slip-off slope (or point bar) is formed on the inner bend.

(b) (ii) How human activities increase flood risk:
- Deforestation (clearing trees) reduces interception rates, which increases surface runoff and speeds up the delivery of rainwater to the river channel.
- Urbanisation (building roads, houses, and concrete surfaces) creates impermeable surfaces that prevent infiltration, leading to a rapid rise in river discharge.
- Inefficient urban drainage networks channel stormwater directly and rapidly into rivers, reducing the lag time.
- Intensive farming / overgrazing compacts soil, reducing its permeability and increasing overland flow.
- Straightening river channels elsewhere can speed up flow downstream, causing sudden surges of water in lower-lying areas.

评分标准

(a) (i) 1 mark for identifying:
- Plunge pool

(ii) 3 marks for naming and describing three distinct processes (1 mark per process):
- Hydraulic action: Force of water wears away river bed/banks / forces air into cracks.
- Abrasion: River cargo / rocks wear away the bed/banks like sandpaper.
- Attrition: Stones collide and break down into smaller/rounder particles.
- Solution: Acids in water dissolve soluble rocks (e.g., limestone).

(iii) 5 marks total for explaining waterfall formation and retreat:
- Hard rock lies over soft rock (1 mark)
- Soft rock is eroded faster / undercut (1 mark)
- Creates an overhang of hard rock (1 mark)
- Overhang collapses due to lack of support / gravity (1 mark)
- Plunge pool forms at the base due to swirling rocks/water force (1 mark)
- Process repeats causing waterfall to retreat upstream / leaves a gorge (1 mark)

(b) (i) 4 marks total for comparing outer and inner bends (must contain comparative points):
- Outer bend is faster-flowing / high velocity AND inner bend is slower-flowing / low velocity (1 mark)
- Outer bend is deeper AND inner bend is shallower (1 mark)
- Outer bend undergoes erosion AND inner bend undergoes deposition (1 mark)
- Outer bend forms a river cliff AND inner bend forms a slip-off slope / point bar (1 mark)

(b) (ii) 5 marks total for explaining human activities increasing flood risk (max 1 mark per point; 1 additional mark for developed reasoning):
- Deforestation / clearing forests (1) leads to less interception / more surface runoff (1)
- Urbanisation / concrete surfaces (1) increases impermeable surfaces / reduces infiltration (1)
- Agriculture / plowing up and down slopes (1) creates quick paths for runoff (1)
- Channelisation/straightening upstream (1) increases velocity of water sent downstream (1)
- Climate change from greenhouse emissions (1) increases frequency of intense storm events / rainfall (1)
题目 2 · free-response
7 分
Using a named river you have studied, explain how human activities have increased the risk of flooding.
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解题

Case Study: River Ganges / Brahmaputra (Bangladesh). Human activities have severely exacerbated the risk of flooding along the Ganges-Brahmaputra river system. Firstly, extensive deforestation in the foothills of the Himalayas (Nepal and Northern India) has removed vast areas of forest canopy. This drastically reduces interception and evapotranspiration, meaning a much greater volume of monsoon rainwater immediately becomes surface runoff, rushing into the tributaries and reducing the lag time of the river. Secondly, the removal of vegetation has led to severe soil erosion on steep slopes. This eroded sediment is washed downstream and deposited on the river bed in the flat plains of Bangladesh, raising the river bed level, which greatly reduces the channel's carrying capacity and makes it spill over its banks much more easily. Finally, rapid urbanisation in cities like Dhaka has replaced natural wetlands and soil with impermeable concrete and tarmac. This prevents infiltration, creating high volumes of rapid urban runoff through drains directly into the river system, significantly raising peak discharge during storm events.

评分标准

Level 1 (1 to 3 marks): Simple statements explaining human causes of flooding. [e.g., Cutting down trees makes it flood more; building cities with concrete stops water sinking in; building embankments can trap water.] Level 2 (4 to 6 marks): Developed statements showing how these human activities physically increase flood risk. [e.g., Deforestation in the drainage basin reduces interception, which increases surface runoff and decreases the lag time of the river; urbanisation creates impermeable concrete surfaces, preventing infiltration and causing rapid overland flow into the channel, raising peak discharge.] Level 3 (7 marks): Comprehensive explanation with three or more developed points, naming a specific river, with place-specific details. [e.g., Named river: Ganges/Brahmaputra River. Details include: Deforestation in Nepal/Himalayas, soil erosion raising the river bed in Bangladesh, urbanisation in Dhaka creating impermeable surfaces, or referencing specific severe floods like 1998/2004.]

卷一 部分 C (Economic Development)

Answer one question from this section.
3 题目 · 32 分
题目 1 · structured
18 分
Study the following data representing the percentage of electricity generated from different sources in a country between 2005 and 2025: Coal (2005: 60%, 2015: 45%, 2025: 25%), Natural Gas (2005: 20%, 2015: 25%, 2025: 30%), Hydroelectric Power (HEP) (2005: 15%, 2015: 18%, 2025: 20%), and Wind & Solar (2005: 5%, 2015: 12%, 2025: 25%). (a)(i) What percentage of electricity was generated from Coal in 2015? [1] (a)(ii) Using the data provided, compare the changes in electricity generated from Natural Gas with Wind & Solar between 2005 and 2025. Do not use statistics. [2] (a)(iii) Suggest three reasons why many countries are increasing their use of renewable energy sources such as wind and solar power. [3] (b)(i) Suggest three physical factors that need to be considered when choosing a site for a large solar power farm. [3] (b)(ii) Explain how the construction and operation of a large hydroelectric power (HEP) scheme can affect the local natural environment and communities. [4] (b)(iii) Explain the disadvantages of relying heavily on fossil fuels (such as coal and oil) to generate electricity. [5]
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解题

(a)(i) 45%. (a)(ii) Both energy sources increased their share of generation over the 20-year period. However, Wind & Solar grew at a much faster rate / had a larger overall increase compared to the slower, more steady growth of Natural Gas. (a)(iii) 1. Renewable sources are sustainable and will not run out, unlike finite fossil fuels. 2. They do not emit greenhouse gases like carbon dioxide during generation, reducing the impact on global warming. 3. Running costs are minimal once the initial infrastructure is set up, and they help countries achieve energy independence. (b)(i) 1. High levels of solar insolation with long daily hours of clear, unobstructed sunshine. 2. Flat or gently sloping terrain to make the installation of large solar arrays easier and cheaper. 3. Large open areas of low-value land, such as deserts or arid scrubland, to minimize land-use conflict. (b)(ii) The construction of a large reservoir floods vast areas of land upstream, which destroys natural forest ecosystems, causes loss of biodiversity, and displaces local villages or farmlands. Downstream, the dam alters natural river flows and blocks migratory pathways for fish species, while decaying organic matter in the new reservoir can release substantial amounts of methane gas. (b)(iii) Burning fossil fuels releases carbon dioxide into the atmosphere, which traps heat and intensifies the greenhouse effect, leading to rising global temperatures and extreme weather events. It also releases sulfur dioxide and nitrogen oxides, which combine with atmospheric moisture to form acid rain, harming forests and aquatic life. Additionally, fossil fuel extraction physically scars the landscape, and transporting oil carries severe risks of spills that can devastate marine and coastal environments.

评分标准

(a)(i) 45% = 1 mark. (a)(ii) 2 @ 1 mark: One mark for recognizing that both increased; One mark for recognizing that Wind & Solar increased much faster/by a larger margin. (a)(iii) 3 @ 1 mark: Accept points such as: Finite nature of fossil fuels / renewable sources will not run out; Mitigation of global warming / reduces carbon footprint / no greenhouse gases; Lower operational costs / no fuel costs after setup; Government policies / international environmental treaties. (b)(i) 3 @ 1 mark: Accept points such as: High solar radiation/sunny climate; Flat/gently sloping land; Large open areas/cheap land; Low risk of shading from trees or high-rise buildings. (b)(ii) 4 @ 1 mark (or development): Upstream flooding drowns habitats / loss of flora and fauna; Forced displacement of local residents / loss of agricultural livelihoods; Disruption to downstream river hydrology / impact on downstream agriculture or fishing; Interference with fish migration routes; Methane emissions from drowned decaying vegetation. (b)(iii) 5 @ 1 mark (or development): Releases carbon dioxide [1] leading to global warming/climate change [1]; Releases sulfur dioxide/nitrogen oxides [1] which causes acid rain [1]; Fossil fuels are finite/will run out [1]; Extraction scars the landscape (e.g., open-cast mining) [1]; Transportation risks like oil spills pollute aquatic habitats [1].
题目 2 · essay
7 分
With reference to a named country or region you have studied, describe and explain the advantages and challenges of a specific scheme used to produce renewable energy.
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解题

An excellent response will focus on a specific, real-world renewable energy project. Candidates should name both the country/region and the specific scheme (e.g., Three Gorges Dam in China, Itaipu Dam in Brazil/Paraguay, or London Array wind farm in the UK).

For a high-scoring answer (Level 3):
1. Clearly state the country and the named renewable energy scheme (e.g., Three Gorges Dam, China).
2. Provide at least three developed points (Level 2) that explain either an advantage or a challenge.
3. Include place-specific details (e.g., Yangtze River, 22,500 MW capacity, 1.3 million people displaced, etc.).

Example Level 3 Response:
In China, the Three Gorges Dam HEP scheme on the Yangtze River was built to meet the country's soaring demand for electricity. One major advantage is that it has a massive capacity of 22,500 MW, providing clean electricity to major industrial hubs like Shanghai and reducing coal consumption by millions of tonnes annually. Additionally, the dam helps regulate river flow, preventing severe seasonal floods that historically devastated communities downstream in the Middle Yangtze plains. However, the scheme faced massive challenges; the filling of the 600 km long reservoir drowned valuable agricultural land, forcing the relocation of more than 1.3 million residents from cities like Wanxian. Furthermore, it has severely disrupted river ecosystems, blocking the migration routes of the endangered Chinese sturgeon.

评分标准

Generic Marking Principles for Case Studies:
- Level 1 (1-3 marks): 1 to 3 simple statements.
- Level 2 (4-6 marks): 1 developed statement = 4 marks; 2 developed statements = 5 marks; 3 or more developed statements = 6 marks. (Max 5 marks if no named or inappropriate example is used).
- Level 3 (7 marks): 3 or more developed statements + named example + at least one piece of place-specific detail.

Acceptable schemes include:
- Three Gorges Dam (China)
- Itaipu Dam (Brazil/Paraguay)
- Kariba Dam (Zimbabwe/Zambia)
- Aswan High Dam (Egypt)
- London Array Wind Farm (UK)
- Geysers Geothermal Complex (USA)

Do not credit non-renewable schemes (e.g., coal, gas, nuclear).
题目 3 · essay
7 分
With reference to a named country or region you have studied, describe and explain the advantages and challenges of a specific scheme used to produce renewable energy.
查看答案详解

解题

An excellent response will focus on a specific, real-world renewable energy project. Candidates should name both the country/region and the specific scheme (e.g., Three Gorges Dam in China, Itaipu Dam in Brazil/Paraguay, or London Array wind farm in the UK).

For a high-scoring answer (Level 3):
1. Clearly state the country and the named renewable energy scheme (e.g., Three Gorges Dam, China).
2. Provide at least three developed points (Level 2) that explain either an advantage or a challenge.
3. Include place-specific details (e.g., Yangtze River, 22,500 MW capacity, 1.3 million people displaced, etc.).

Example Level 3 Response:
In China, the Three Gorges Dam HEP scheme on the Yangtze River was built to meet the country's soaring demand for electricity. One major advantage is that it has a massive capacity of 22,500 MW, providing clean electricity to major industrial hubs like Shanghai and reducing coal consumption by millions of tonnes annually. Additionally, the dam helps regulate river flow, preventing severe seasonal floods that historically devastated communities downstream in the Middle Yangtze plains. However, the scheme faced massive challenges; the filling of the 600 km long reservoir drowned valuable agricultural land, forcing the relocation of more than 1.3 million residents from cities like Wanxian. Furthermore, it has severely disrupted river ecosystems, blocking the migration routes of the endangered Chinese sturgeon.

评分标准

Generic Marking Principles for Case Studies:
- Level 1 (1-3 marks): 1 to 3 simple statements.
- Level 2 (4-6 marks): 1 developed statement = 4 marks; 2 developed statements = 5 marks; 3 or more developed statements = 6 marks. (Max 5 marks if no named or inappropriate example is used).
- Level 3 (7 marks): 3 or more developed statements + named example + at least one piece of place-specific detail.

Acceptable schemes include:
- Three Gorges Dam (China)
- Itaipu Dam (Brazil/Paraguay)
- Kariba Dam (Zimbabwe/Zambia)
- Aswan High Dam (Egypt)
- London Array Wind Farm (UK)
- Geysers Geothermal Complex (USA)

Do not credit non-renewable schemes (e.g., coal, gas, nuclear).

卷二 Map Work

Compulsory topographical map question.
1 题目 · 20 分
题目 1 · subjective
20 分
Study the map extract for Oakford Valley. The scale is 1:25 000.

(a) Study the sketch map (Fig. 1.1) below, which shows some of the features in the northwest of the map extract.

[Fig. 1.1 Sketch Map details:
- Grid lines: Eastings 20 to 24, Northings 45 to 49
- A: A main dual-carriageway road crossing grid square 2148
- B: A river named 'Oakford River' flowing southwards
- C: A spot height in grid square 2247 labeled '182'
- D: A steep escarpment/cliff line on the west side of the river
- E: A small nucleated village named 'Westwood' in grid square 2049
- F: A lookout tower located at Easting 21.8, Northing 47.5]

Using the map extract, identify the following features shown in Fig. 1.1:
(i) the type of road at A [1]
(ii) the name of the river at B [1]
(iii) the height above sea level of the spot height at C [1]
(iv) physical feature D [1]
(v) the name of the settlement at E [1]

(b) Give the six-figure grid reference of the lookout tower, F, shown in Fig. 1.1. [1]

(c) Find the settlement of 'Hillview' in grid square 2346.
(i) Identify the settlement pattern of Hillview. Choose from: linear, nucleated, dispersed. [1]
(ii) Give a reason for this settlement pattern. [1]

(d) Find the orange secondary road (Route 404) in the east of the map extract.
(i) What is the distance in metres along the orange secondary road 404 between the bridge in grid square 2445 and the road intersection in grid square 2447? [1]
(ii) What is the compass direction from the bridge in grid square 2445 to the campsite in grid square 2448? [1]

(e) Fig. 1.2 is a cross-section along northing 47 from 200470 to 240470.
(i) Identify the feature at X (located at 208470). [1]
(ii) Identify the feature at Y (located at 215470). [1]
(iii) The cross-section shown in Fig. 1.2 is incomplete. Describe how to complete the cross-section line between Eastings 22 and 24, where it crosses a hill reaching a peak of 310m. [2]

(f) Study the river flowing between the north and south of the map extract. Describe the physical (natural) features of the river and its valley. Do not refer to land use beside the river. [6]
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解题

(a) (i) Dual-carriageway / Main arterial road (accept: primary road / A-road)
(ii) Oakford River
(iii) 182 metres
(iv) Cliff / Escarpment / Ridge / Steep slope
(v) Westwood

(b) 218475 (accept 217475 to 219475)

(c) (i) Dispersed
(ii) Located on rugged, steep terrain where flat building space is limited and farms are widely spread out.

(d) (i) 1500 metres (accept 1400 m to 1600 m)
(ii) North / N (accept NNE)

(e) (i) Railway line
(ii) Oakford River / River channel
(iii) Draw/describe a line rising steadily from 270m at Easting 22 to a peak of 310m at Easting 22.8, then falling back to approximately 260m at Easting 23.5 before matching the end slope.

(f) River Features:
- Meandering course / sinuous pattern
- Flows generally southwards
- Varying width (narrower in northern valley, wider in south)
- Presence of tributaries / confluences
- Minor islands / shingle banks
Valley Features:
- Steep-sided in the upper / northern valley
- Flat valley floor / floodplain in the south
- Asymmetrical slopes (steeper east side, gentler west side)
- U-shaped valley floor in lower course

评分标准

(a) (i) Dual-carriageway / Primary road = 1 mark
(ii) Oakford River = 1 mark
(iii) 182 (metres) = 1 mark
(iv) Cliff / steep slope / escarpment = 1 mark
(v) Westwood = 1 mark

(b) 218475 (allow Eastings: 217-219, Northings: 474-476) = 1 mark

(c) (i) Dispersed = 1 mark
(ii) Steep slopes / rugged relief / lack of flat land / agricultural farms spread out = 1 mark

(d) (i) 1500 (metres) (allow 1400m to 1600m) = 1 mark
(ii) North / N / NNE = 1 mark

(e) (i) Railway (line) = 1 mark
(ii) Oakford River / River = 1 mark
(iii) Peak drawn/described at 310m (+/- 10m) = 1 mark; Line passes through 260m (+/- 10m) at Easting 23.5 = 1 mark

(f) Max 4 marks for river or valley features individually. Total max 6 marks.
River features (max 4 marks):
- Meandering / sinuous / winding course (1)
- Flows southwards / south-southwest (1)
- Variable width (1)
- Confluence / tributaries join (1)
- Presence of slip-off slopes / river cliffs (1)
Valley features (max 4 marks):
- Steep sides (1)
- Flat floor / presence of floodplain (1)
- Asymmetrical cross-section (1)
- V-shaped in north / U-shaped in south (1)
- Narrow / variable width of valley floor (1)

卷二 短題目

Answer all questions in this section.
5 题目 · 40 分
题目 1 · short
8 分
Table 1.1 shows demographic data for Country X between 1990 and 2020. Table 1.1: 1990: Birth Rate = 38 per 1000, Death Rate = 14 per 1000; 2000: Birth Rate = 32 per 1000, Death Rate = 9 per 1000; 2010: Birth Rate = 24 per 1000, Death Rate = 6 per 1000; 2020: Birth Rate = 15 per 1000, Death Rate = 5 per 1000. (a) (i) Calculate the natural increase per 1000 for Country X in the year 2010. [1] (ii) Identify the year in which Country X experienced the highest rate of natural increase. [1] (b) Describe how and suggest why the death rate of Country X changed between 1990 and 2020. [3] (c) Suggest three reasons why birth rates decrease as a country develops. [3]
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解题

(a)(i) Natural increase = Birth Rate - Death Rate = 24 - 6 = 18 per 1000. (a)(ii) 2000 (Natural increase was 32 - 9 = 23 per 1000, which is the highest). (b) The death rate fell from 14 to 5 per 1000 (a decrease of 9 per 1000). This decrease occurred because of improvements in medical technology, more clinics/hospitals, better diets/nutrition, and more reliable access to clean drinking water. (c) Reasons for decreasing birth rates: 1. Higher availability/use of contraception. 2. Higher female literacy/career focus, delaying childbirth. 3. Decreasing infant mortality rates, meaning fewer replacement births are needed. 4. High costs of raising children in industrial societies. 5. Government pension schemes reducing the need for children to support parents in old age.

评分标准

(a)(i) 18 / 18 per 1000 [1 mark] (a)(ii) 2000 [1 mark] (b) Description: Decreased/declined overall (from 14 to 5) [1 mark]. Explanations (max 2 marks): Improved healthcare/hospitals/clinics; immunisation/vaccinations; better sanitation/clean water; improved diet/nutrition/food security [2 marks]. (c) 1 mark per valid reason (max 3 marks): Availability/education of contraception; female emancipation/careers/later marriage; lower infant mortality; high cost of raising children; introduction of state pensions.
题目 2 · short
8 分
Fig. 2.1 shows a settlement hierarchy and service threshold model. Hamlet: Threshold population = 50, low-order services. Village: Threshold population = 500, low-order services. Small Town: Threshold population = 5000, middle-order services. City: Threshold population = 50000, high-order services. (a) (i) Define the term 'threshold population'. [1] (ii) State the minimum population required to support a middle-order service according to Fig. 2.1. [1] (b) Describe the relationship between settlement size, number of services, and sphere of influence. [3] (c) Explain why low-order services are more frequently found in villages than high-order services. [3]
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解题

(a)(i) Threshold population is the minimum number of customers/people needed to make a shop or service profitable. (a)(ii) 5000. (b) As the size of a settlement increases, both the number of services and the scale/size of its sphere of influence increase. High-order services are concentrated in larger settlements. (c) Low-order services (like a small grocery store) have a small threshold population, which can be satisfied by a village's small population. High-order services (like department stores) require a large threshold population which villages do not have. Furthermore, low-order items are used frequently, so people do not want to travel far for them.

评分标准

(a)(i) Minimum number of people/customers needed to support a service/make it profitable [1 mark]. (a)(ii) 5000 [1 mark]. (b) 1 mark per valid point (max 3 marks): Larger settlements have a larger number of services; larger settlements have a wider/larger sphere of influence; smaller settlements have fewer/low-order services; smaller settlements have a smaller sphere of influence. (c) 1 mark per valid point (max 3 marks): Villages have small populations which meet the low threshold of low-order services; villages do not have enough people to meet the high threshold needed for high-order services; low-order services are convenience goods/needed daily so people will not travel far; high-order services are comparison goods/needed less frequently.
题目 3 · short
8 分
Table 3.1 shows weather data recorded at a weather station over a 12-hour period. Table 3.1: 08:00: Temp = 18C, Pressure = 1012 mb, Wind Direction = SW, Rainfall = 0 mm; 12:00: Temp = 22C, Pressure = 1008 mb, Wind Direction = SW, Rainfall = 2 mm; 16:00: Temp = 24C, Pressure = 1004 mb, Wind Direction = W, Rainfall = 5 mm; 20:00: Temp = 19C, Pressure = 1010 mb, Wind Direction = NW, Rainfall = 1 mm. (a) (i) State the instrument used to measure atmospheric pressure. [1] (ii) Calculate the temperature range during this 12-hour period. [1] (b) Describe how wind direction and atmospheric pressure changed as the rainfall increased. [2] (c) Explain how a maximum-minimum thermometer (Six's thermometer) is used to record daily temperatures. [4]
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解题

(a)(i) A barometer is used to measure atmospheric pressure. (a)(ii) Temperature range = Maximum Temperature - Minimum Temperature = 24C - 18C = 6C. (b) As rainfall increased (from 0 to 5 mm), the wind direction shifted from SW to W, and atmospheric pressure dropped from 1012 mb to 1004 mb. (c) A maximum-minimum thermometer contains alcohol and mercury. When temperatures rise, alcohol in the left bulb expands, pushing the mercury up on the right (maximum) side, pushing a metal index up. When it cools, the alcohol contracts, and the mercury rises on the left (minimum) side, pushing another index. The bottom of each index shows the respective maximum and minimum temperature. A magnet is used to reset the indexes daily.

评分标准

(a)(i) Barometer / aneroid barometer [1 mark] (a)(ii) 6C / 6 [1 mark] (b) Wind direction changed/shifted from SW to W [1 mark]; atmospheric pressure decreased / fell [1 mark]. (c) Max 4 marks: Contains mercury and alcohol [1 mark]; expansion of alcohol when warm pushes mercury up maximum side [1 mark]; contraction of alcohol when cool causes mercury to rise on minimum side [1 mark]; metal indices/markers are pushed up by the mercury [1 mark]; indicators stay in place when the mercury retreats [1 mark]; temperatures are read from the bottom of the indices [1 mark]; reset daily using a magnet [1 mark].
题目 4 · short
8 分
Table 4.1 shows river channel characteristics at three different sites along the River Eden. Table 4.1: Site X: Width = 1.2 m, Average Depth = 0.15 m, Velocity = 0.3 m/s; Site Y: Width = 5.4 m, Average Depth = 0.60 m, Velocity = 0.7 m/s; Site Z: Width = 15.2 m, Average Depth = 1.80 m, Velocity = 1.1 m/s. (a) (i) Identify which site (X, Y, or Z) represents the upper course of the river. [1] (ii) Describe the trend in river velocity from the source to the mouth shown in Table 4.1. [1] (b) Describe how a river channel changes downstream. Use statistics from Table 4.1 to support your answer. [2] (c) State and explain two processes of river transportation. [4]
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解题

(a)(i) Site X has the smallest width and depth, which represents the upper course of the river. (a)(ii) River velocity increases downstream (from 0.3 m/s to 1.1 m/s). (b) The river channel becomes both wider and deeper downstream. This is shown by width increasing from 1.2 m to 15.2 m, and average depth increasing from 0.15 m to 1.80 m. (c) Processes of river transportation include: 1. Traction: large, heavy rocks and boulders are rolled along the river bed because they are too heavy to lift. 2. Suspension: small, light particles of silt and clay are carried along suspended in the water without touching the bed.

评分标准

(a)(i) Site X [1 mark] (a)(ii) Increases downstream / becomes faster [1 mark] (b) Channel gets wider and deeper downstream [1 mark]. Correct comparative statistics used from the table [1 mark] (e.g. width increases from 1.2m to 15.2m / depth increases from 0.15m to 1.80m). (c) State and explain any two transport processes (max 4 marks, 1 mark for state, 1 mark for explanation): Traction: large rocks/boulders rolled along the bed [2 marks]. Saltation: pebbles/sand grains bounced along the river bed [2 marks]. Suspension: fine silt/clay particles suspended/carried in the water [2 marks]. Solution: dissolved minerals carried in chemical form [2 marks].
题目 5 · short
8 分
Table 5.1 shows the percentage of water used by different sectors in Country A (an LEDC) and Country B (an MEDC). Table 5.1: Sector: Agriculture (Country A = 82%, Country B = 35%); Sector: Industry (Country A = 8%, Country B = 45%); Sector: Domestic (Country A = 10%, Country B = 20%). (a) (i) State the sector that consumes the least water in Country B. [1] (ii) Compare the industrial water use in Country A and Country B. [1] (b) Suggest reasons for the differences in domestic water use between Country A and Country B. [2] (c) Explain the methods used to manage water supply sustainably in areas facing water shortages. [4]
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解题

(a)(i) The domestic sector has the lowest water consumption in Country B (20%). (a)(ii) Country B uses significantly more water for industry (45%) than Country A (8%). (b) Developed countries like Country B have greater access to domestic plumbing, showers, flushing toilets, and household appliances like washing machines and dishwashers. In contrast, many families in LEDCs like Country A must fetch water from communal wells, limiting domestic consumption. (c) Sustainable water management techniques: 1. Rainwater harvesting: collecting precipitation on roofs to store in tanks. 2. Water recycling/reuse: filtering greywater from bathing/washing for use in irrigation or toilet flushing. 3. Reservoirs: constructing dams to capture surplus winter rainfall for summer use. 4. Water metering: charging consumers based on actual volume consumed, which encourages conservation and reduces leaks.

评分标准

(a)(i) Domestic [1 mark] (a)(ii) Country B uses more water for industry than Country A (45% vs 8%) [1 mark]. (b) 1 mark per valid reason (max 2 marks): Country B has higher living standards / more domestic appliances / washing machines / dishwashers; Country B has piped water directly connected to homes; Country A has less infrastructure / lack of indoor plumbing / must fetch water manually. (c) Max 4 marks for methods explained: Rainwater harvesting / capturing rainfall from roofs [1 mark] to use for irrigation/toilets [1 mark]; Reservoirs / dams [1 mark] to store water from wet seasons [1 mark]; Greywater recycling / recycling wastewater [1 mark] for agricultural or domestic use [1 mark]; Water metering / volumetric pricing [1 mark] to discourage wasteful usage [1 mark]; Desalination [1 mark] to convert seawater to freshwater [1 mark]; Fixing pipe leaks [1 mark] to prevent physical loss of water [1 mark].

Paper 4 Fieldwork 1

Compulsory coursework investigation simulation.
1 题目 · 30 分
题目 1 · practical
30 分
Students in Spain carried out fieldwork along a tributary of the Ebro River, called the River Jalón, to investigate how river characteristics change downstream. They selected six sites along the river course.

(a) (i) The students collected both primary and secondary data. Explain the difference between primary and secondary data. [2]

(ii) State two safety precautions that the students should take before and during their river fieldwork. [2]

(b) To investigate Hypothesis 1: River velocity increases downstream, the students used a float to measure velocity.

(i) Describe a method the students could use to measure river velocity using a float, tape measure, and stopwatch. [4]

(ii) Other students in the group used a digital flow meter to measure velocity. Suggest two advantages of using a digital flow meter instead of a float. [2]

(iii) The students recorded their velocity measurements in Table 1.1.

Table 1.1: Average velocity measurements at six sites
- Site 1: Distance from source = 1.2 km, Average velocity = 0.25 m/s
- Site 2: Distance from source = 3.5 km, Average velocity = 0.38 m/s
- Site 3: Distance from source = 6.8 km, Average velocity = 0.44 m/s
- Site 4: Distance from source = 9.2 km, Average velocity = 0.42 m/s
- Site 5: Distance from source = 12.5 km, Average velocity = 0.58 m/s
- Site 6: Distance from source = 15.1 km, Average velocity = 0.65 m/s

The students plotted these results on a scatter graph (Fig. 1.1), but they did not plot the result for Site 4. Describe how the students would plot the point for Site 4 on Fig. 1.1. [2]

(iv) What conclusion would the students make about Hypothesis 1: River velocity increases downstream? Support your answer with evidence from Table 1.1. [4]

(c) The students also investigated Hypothesis 2: Average bedload (pebble) size decreases downstream.

(i) Describe how the students could select a sample of 10 pebbles from the river bed at each site using a systematic sampling method to avoid bias. [3]

(ii) The students measured the longest axis of each pebble. Put the following steps A to D in the correct chronological order to describe the measurement process using a caliper.
- A: Read and record the measurement in millimeters on the caliper scale.
- B: Pick up a pebble from the river bed sample.
- C: Place the pebble between the jaws of the caliper.
- D: Close the caliper jaws firmly around the longest axis of the pebble.
[2]

(iii) Table 1.2 shows the average pebble length at six sites:
- Site 1: 84 mm
- Site 2: 68 mm
- Site 3: 52 mm
- Site 4: 41 mm
- Site 5: 30 mm
- Site 6: 15 mm

The students drew a bar chart to represent these results. Describe how they would construct the bar representing Site 5. [2]

(iv) What conclusion would the students make about Hypothesis 2: Average bedload (pebble) size decreases downstream? Support your answer with evidence from Table 1.2. [4]

(d) Suggest one other river characteristic (other than velocity or bedload size) that could be investigated to see how it changes downstream. Describe how the students would measure this characteristic in the field. [3]
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解题

(a) (i) Primary data is collected first-hand by the researcher/students through direct fieldwork measurement. Secondary data is already pre-existing data compiled by someone else from books, internet resources, maps, etc.

(ii) Safety precautions: Wear appropriate protective footwear/waders; check weather forecasts to avoid high-flow/flood conditions; work in pairs/groups; do not wade into water deeper than knee-level or very fast-flowing.

(b) (i) 1. Measure a fixed distance (e.g., 10m) along the river bank using a tape measure.
2. Mark the start and end lines with ranging poles.
3. Drop a floating object (e.g., an orange) slightly upstream of the start line.
4. Start the stopwatch when the float passes the start line and stop it when it passes the end line.
5. Repeat the process at least three times to find the average time.
6. Calculate velocity as distance divided by average time.

(ii) 1. Eliminates human error related to manual stopwatch starting/stopping.
2. Measures velocity below the water surface (not affected by wind or surface tension).

(iii) On the horizontal axis (Distance from source), locate the 9.2 km position. On the vertical axis (Average velocity), locate the 0.42 m/s position. Draw a dot or an 'X' where these two grid lines intersect.

(iv) Hypothesis 1 is true/partially true. River velocity generally increases with distance downstream. Evidence: Velocity increases from 0.25 m/s at Site 1 (1.2 km from source) to 0.65 m/s at Site 6 (15.1 km from source). Anomaly: Site 4 (0.42 m/s) is slightly slower than Site 3 (0.44 m/s) despite being further downstream.

(c) (i) Lay a transect tape measure across the river bed from one bank to the other. Divide the width of the river by 10 to establish equal interval points. Pick the pebble closest to the river bed directly below each calculated interval mark without looking/bias.

(ii) The correct order is B -> C -> D -> A.

(iii) Locate Site 5 on the x-axis. Draw a vertical bar centered over Site 5 up to the height of 30 mm on the y-axis. Shade the bar using the same style/color as the rest of the chart.

(iv) Hypothesis 2 is true. Average pebble size decreases with distance downstream. Evidence: Average pebble length falls steadily from 84 mm at Site 1 (1.2 km from source) to 15 mm at Site 6 (15.1 km from source).

(d) Named characteristic: Channel Width.
Method: Stretch a tape measure taut across the wet channel from one bank to the other perpendicular to the river's flow, and read the width measurement where it meets the water's edge on both banks.

评分标准

Total Marks: 30

(a) (i) 1 mark for primary data definition, 1 mark for secondary data description. [2]

(ii) 2 marks for any two logical precautions (e.g., check weather, wear waders, work in groups, avoid deep water). [2]

(b) (i) 4 @ 1 mark for key steps: measuring distance, timing float, repeats, calculation. [4]

(ii) 2 @ 1 mark for benefits of flow meter (no human reaction error, measures at depth, unaffected by wind). [2]

(iii) 1 mark for locating correct x-coordinate (9.2), 1 mark for correct y-coordinate (0.42). [2]

(iv) 1 mark for concluding Hypothesis 1 is true. 2 marks for paired supporting data (Sites 1 and 6). 1 mark for identifying Site 4 as an anomaly. [4]

(c) (i) 3 @ 1 mark for: tape across channel, calculate equal intervals, picking pebble at exact interval without looking. [3]

(ii) 2 marks for exact order: B, C, D, A. 1 mark if two are in relative order. [2]

(iii) 1 mark for drawing correct height (30 mm), 1 mark for width/shading/placement on the horizontal axis. [2]

(iv) 1 mark for concluding Hypothesis 2 is true. 2 marks for paired supporting data (Sites 1 and 6). 1 mark for stating that the downward trend is consistent. [4]

(d) 1 mark for naming an alternative characteristic (e.g., width, depth, roundness, discharge). 2 marks for describing a valid field method. [3]

Paper 4 Fieldwork 2

Compulsory coursework investigation simulation.
1 题目 · 30 分
题目 1 · theory
30 分
Students in Mombasa, Kenya, carried out fieldwork to investigate differences in water supply and sanitation between two suburbs: Nyali (a high-income residential area) and Likoni (a low-income informal settlement area). They chose two hypotheses to investigate:

**Hypothesis 1**: *Households in Likoni spend a larger percentage of their weekly income on securing water than households in Nyali.*

**Hypothesis 2**: *The use of untreated or informal water sources is associated with higher rates of stomach illnesses.*

(a) (i) The students drafted a questionnaire. One question they wrote was:

*"Do you agree that your household water is bad and too expensive?"*

Explain two reasons why this is a poorly designed question. [2]

(ii) The students conducted a pilot study with 15 households in Nyali before starting their main survey.
State two reasons why carrying out a pilot study is useful. [2]

(b) (i) The students wanted to obtain a representative sample of 100 households in each suburb. They decided to use **stratified sampling** based on housing types (e.g., apartment blocks, detached houses, informal shacks).
Describe how the students would carry out a stratified sampling method. [3]

(ii) Suggest one advantage and one disadvantage of using stratified sampling rather than random sampling in this study. [2]

(c) The results for the percentage of weekly household income spent on water are shown in Table 1.1.

**Table 1.1: Percentage of weekly household income spent on water**

| Percentage of income spent on water | Nyali (number of households) | Likoni (number of households) |
| :--- | :--- | :--- |
| Less than 2% | 75 | 5 |
| 2% to 5% | 20 | 15 |
| 6% to 10% | 5 | 45 |
| More than 10% | 0 | 35 |
| **Total** | **100** | **100** |

(i) Use the data in Table 1.1 to describe how you would complete a divided bar graph for **Likoni** (assuming a single bar represents 100 households/percent). State at which cumulative percentage values you would draw the dividing lines to separate the four categories. [3]

(ii) What conclusion would the students make regarding **Hypothesis 1**? Support your conclusion with data from Table 1.1. [4]

(d) The main sources of water used by households in both suburbs are shown in Table 1.2.

**Table 1.2: Main household water sources in Nyali and Likoni**

| Main water source | Nyali (% of households) | Likoni (% of households) |
| :--- | :--- | :--- |
| Public piped utility (tap) | 88 | 12 |
| Private borehole | 10 | 18 |
| Commuter water kiosk | 2 | 30 |
| Mobile water tanker / informal vendor | 0 | 40 |

(i) If you were to plot the data for **Likoni**'s water sources on a bar graph, state the height (in percentage) that each of the four bars should be. [2]

(ii) Using Table 1.2, compare the household water sources in Nyali and Likoni. **Do not** use statistics in your answer. [3]

(iii) Explain why relying on mobile water tankers or informal vendors can lead to both higher water costs and increased health risks for residents in settlements like Likoni. [4]

(e) Suggest two low-cost methods, other than constructing a piped water network, that residents or local groups in Likoni could use to make their drinking water safer. [2]

(f) The students decided to extend their study by testing the physical and chemical quality of water from three local boreholes.
Describe how they could measure:
- pH of the water [1]
- turbidity (clarity) of the water [2]
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解题

All sub-questions have been fully addressed with detailed solutions and marking guidelines provided directly in the marking scheme.

评分标准

**(a) (i)** Award up to 2 marks for points such as:
- It is a leading question / biased towards agreement (1)
- Double-barreled / asks two different things (quality and cost) at once (1)
- No neutral or gradient choice option provided (1)

**(a) (ii)** Award up to 2 marks for points such as:
- Test if questions are clear / easily understood (1)
- Practice survey technique / build confidence (1)
- Estimate questionnaire duration to manage fieldwork time (1)
- Identify if any response categories are missing from multiple-choice lists (1)

**(b) (i)** Award up to 3 marks for points such as:
- Determine the proportion of each housing type in the total population of the suburb (1)
- Select sample sizes for each housing type that match these proportions (1)
- Sample households within each stratum using systematic/random sampling (1)

**(b) (ii)** Award 1 mark for advantage, 1 mark for disadvantage:
- *Advantage*: Representative of all housing types / avoids underrepresenting minor groups / high accuracy (1)
- *Disadvantage*: Difficult/time-consuming to obtain background demographic data / complex to organize (1)

**(c) (i)** Award 1 mark for each correct cumulative dividing line location:
- First line at 5% (1)
- Second line at 20% (1)
- Third line at 65% (1)

**(c) (ii)** Award 1 mark for hypothesis decision, up to 3 marks for data support (including at least one set of paired comparative data):
- Hypothesis 1 is true / supported (1 - reserve mark)
- In Likoni, 80% of households spend 6% or more of their weekly income on water, compared to only 5% of households in Nyali (1)
- In Nyali, 75% of households spend less than 2% of their weekly income on water, compared to only 5% of households in Likoni (1)
- Direct comparison of a single category: e.g., 35% of Likoni households spend >10% of their income on water, while 0% of Nyali households do (1)

**(d) (i)** Award up to 2 marks for bar plot heights:
- Public piped tap: 12% and Private borehole: 18% (1)
- Commuter water kiosk: 30% and Mobile water tanker: 40% (1)

**(d) (ii)** Award up to 3 marks for comparison points (no statistics allowed):
- Piped public water is much more common in Nyali than Likoni (1)
- Kiosks and mobile tankers are much more widely used in Likoni than Nyali (1)
- Private boreholes are common to both areas, but slightly more frequent in Likoni (1)

**(d) (iii)** Award up to 4 marks (max 2 marks for cost, max 2 marks for health):
- *Cost*: Prices are unregulated / informal vendors can raise prices arbitrarily; high cost of fuel and truck transport is passed on to consumers (2)
- *Health*: Water is unregulated and may be extracted from contaminated sources; containers or tankers may be unhygienic / not cleaned (2)

**(e)** Award up to 2 marks for methods such as:
- Boiling water before consumption (1)
- Chemical treatment, e.g., chlorine tablets / water purification drops (1)
- Solar water disinfection (SODIS) / exposing transparent bottles to sunlight (1)
- Using sand, carbon, or ceramic filters (1)

**(f)**
- *pH*: Dip a digital pH meter/probe into the water and read the value OR use pH indicator paper/test strip and match the color to a reference chart (1)
- *Turbidity*: Pour water slowly into a turbidity tube (1); look down the tube until the Secchi disk at the bottom is no longer visible (1); read and record the depth of water in centimeters from the scale on the tube (1) (Max 2)

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