2024 Edexcel IGCSE Geography 模擬試題連答案詳解

Saltation is the process of transportation where small pebbles and stones are bounced along the river bed by the force of the water. This contrasts with traction (rolling of large boulders), suspension (carrying of fine sediment within the water flow), and solution (transporting of dissolved minerals).

1 mark for the correct option (b). 0 marks for any incorrect option.

Destructive waves have a strong backwash and a weak swash, meaning they remove sediment from the beach, leading to coastal erosion. Constructive waves, on the other hand, build up beaches because they have a strong swash and a weak backwash.

1 mark for the correct option (b). 0 marks for any incorrect option.

1 mark for identifying that the river's sediment load is scraped, ground, or thrown against the bed and banks. 1 mark for explaining that this physical contact wears away, chips, or erodes the channel boundaries.

Award 1 mark for identifying the physical mechanism (e.g., sediment/rocks carried by the river scraping against the bed/banks) (1) and a further 1 mark for explaining the consequence (e.g., which physically wears away and erodes the channel surface) (1).

1 mark for explaining that the swash carries sediment up the beach at an angle matching the prevailing wind direction. 1 mark for explaining that backwash pulls the sediment straight down the beach under gravity, creating a zig-zag movement.

Award 1 mark for explaining the angled movement of sediment up the beach via swash (1) and a further 1 mark for explaining the perpendicular movement down the beach via backwash (1).

1 mark for noting that shield volcanoes erupt highly fluid, low-viscosity basaltic lava. 1 mark for explaining that this lava travels great distances before it solidifies, producing broad, flat slopes.

Award 1 mark for identifying the characteristic of the lava (low viscosity / runny basaltic lava) (1) and a further 1 mark for explaining how this affects the shape (flows a long distance before cooling/solidifying) (1).

1 mark for identifying that flooding causes the river to lose velocity and deposit its coarsest/heaviest load immediately adjacent to the channel. 1 mark for explaining that multiple successive floods accumulate this material to form raised banks.

Award 1 mark for explaining that flooding causes energy loss and deposition of coarse sediment on the river banks (1) and a further 1 mark for explaining that repeated flooding events build up these deposits into raised ridges (1).

A storm hydrograph plot shows how a river's discharge changes over time following a rainfall event. This is shaped by basin characteristics:

1. **Geology**: If a drainage basin is dominated by impermeable rock (like granite or clay), water cannot easily infiltrate the ground. This leads to rapid overland flow (surface runoff), causing water to reach the river channel quickly. This results in a short lag time and a high, steep peak discharge (a 'flashy' hydrograph).

2. **Vegetation**: Areas with dense vegetation cover (such as forests) intercept rainfall with leaves and branches, delaying its descent to the ground. Furthermore, plant roots absorb moisture from the soil. This reduces surface runoff and slows down the movement of water to the river, leading to a longer lag time and a lower, flatter peak discharge (a 'subdued' hydrograph).

Award up to 4 marks for explanatory points, with a maximum of 2 marks for geology and 2 marks for vegetation.

**Geology (Max 2 marks):**
- Impermeable rock/clay reduces infiltration rates and increases surface runoff (1 mark).
- This leads to a shorter lag time and/or a higher peak discharge because water reaches the channel quickly (1 mark).
- *Accept converse for permeable geology (e.g., permits infiltration, leading to longer lag times).*

**Vegetation (Max 2 marks):**
- Vegetation intercepts rainfall and absorbs water through roots (1 mark).
- This delays the water reaching the river channel, resulting in a longer lag time and/or lower peak discharge (1 mark).
- *Accept converse for sparse vegetation/deforested basins.*

A spit is a depositional landform that develops at the coast through the following process:

1. **Longshore Drift**: Prevailing winds push waves toward the shore at an oblique angle. The swash carries sand and shingle up the beach at this angle, while the backwash pulls sediment straight back down the beach under gravity. This continuous zig-zag movement transports sediment along the coastline.
2. **Coastline Change**: Where the coastline changes direction (for example, at an estuary mouth or bay), the sediment continues to be deposited in the same direction rather than following the new line of the coast, into deeper, calmer water.
3. **Accumulation**: Over time, deposition exceeds erosion, and the sediment builds up above sea level, extending out across the estuary.
4. **Hook formation**: A secondary wind direction can cause waves to approach from a different angle, curving the end of the spit to form a hook.

Award 1 mark for each relevant explanatory point, up to a maximum of 4 marks:
- Prevailing winds drive waves to transport sediment along the beach via swash and backwash (longshore drift) (1 mark).
- At a bend or change in the coastline, the energy of the waves drops, leading to the deposition of this sediment (1 mark).
- Continued deposition builds up sediment above high-tide level, extending out into the sea/estuary (1 mark).
- Secondary winds/waves from a different direction cause the end of the spit to curve or form a hook (1 mark).
- *Accept reference to a salt marsh forming in the sheltered area behind the spit (1 mark).*

Sub-aerial processes include weathering (mechanical, chemical, and biological) and mass movement (such as slumping, landslides, and soil creep) which operate on the cliff face above the high tide mark. When cliffs are composed of soft sedimentary rock (such as clay, shale, or poorly consolidated sands), these processes are particularly rapid and destructive.

Weathering processes weaken the structural integrity of the cliff. For example, wetting and drying cycles cause clay minerals to expand when wet and contract when dry, leading to cracking and disintegration. Rainwater infiltrating the permeable layers of sandstone or clay can also lead to chemical weathering, dissolving minerals that cement the grains together.

Mass movement is heavily triggered by this water infiltration. In soft clays, rainwater saturates the rock, increasing its weight and reducing friction along internal slip planes. This frequently leads to rotational slumping, where large sections of the cliff slide downwards and outwards towards the sea. Soil creep and mudflows also transport loose sediment down the slope.

These sub-aerial processes do not act in isolation. Marine processes (such as hydraulic action and abrasion) erode the base of the cliff, removing the slumped material at the toe. This destabilises the cliff face above, triggering further mass movement and weathering, causing rapid and continuous cliff retreat.

Assessment Objectives:
- AO1 (3 marks): Demonstrate knowledge and understanding of sub-aerial processes (weathering and mass movement) and coastal cliff systems.
- AO2 (5 marks): Analyse geographical processes to explain how they interact to cause cliff retreat on soft sedimentary coastlines.

Level Descriptors:

Level 1 (1-3 marks) - Simple or generic:
- Identifies basic processes (e.g., weathering, landslides) but lacks detail.
- Description of cliff retreat is superficial, with little or no reference to 'soft sedimentary' geology.
- Limited structure and geographical vocabulary.

Level 2 (4-6 marks) - Explanatory and structured:
- Explains specific sub-aerial processes, such as freeze-thaw weathering, wetting and drying, or rotational slumping.
- Understands that soft rocks like clay are vulnerable to saturation and weight increase, leading to failure.
- Begins to connect sub-aerial processes with marine erosion (clearing the toe of the cliff), but the analysis of their interaction may be unbalanced.

Level 3 (7-8 marks) - Analytical and comprehensive:
- Detailed, well-balanced analysis of how both weathering and mass movement operate together on soft sedimentary cliffs.
- Clearly explains the mechanics of rotational slumping and clay saturation.
- Explicitly highlights the feedback loop between marine erosion (removing debris) and sub-aerial processes (weakening the cliff face), showing a sophisticated understanding of coastal systems.

A digital flow meter is placed beneath the water's surface to measure the current. This makes it more accurate than a floating object, which only measures surface velocity and can easily be affected by wind resistance or get caught in surface debris.

Award 1 mark for any of the following valid reasons:
- Measures velocity below the surface / at a specific depth (1)
- Not affected by wind or air currents (1)
- Does not get caught on surface debris or bank vegetation (1)
- Reduces human error associated with timing a float with a stopwatch (1)

Reject: 'it is faster' or 'it is more technological' without further explanation.

Systematic sampling relies on pre-determined, regular intervals (e.g., measuring sediment every 5 metres). A major disadvantage of this method is that it can miss key transitional zones or landforms (such as a storm beach or berm) that fall between the chosen sampling points.

Award 1 mark for any of the following valid disadvantages:
- It may miss important variations or features that occur between the fixed intervals (1)
- It can introduce bias if the interval coincides with a natural environmental pattern on the beach (1)
- It might under-represent certain zones of the beach if they are smaller than the interval distance (1)

Reject: 'it is inaccurate' (too vague) or 'it takes too much time'.

To find the mean velocity: 1. Sum the three readings: \(0.42 + 0.55 + 0.47 = 1.44\). 2. Divide the sum by the number of readings: \(1.44 \div 3 = 0.48\). The mean velocity is \(0.48\text{ m/s}\).

Award 1 mark for showing correct working, such as showing the addition of the three values and division by 3: \((0.42 + 0.55 + 0.47) \div 3\) or \(1.44 \div 3\). Award 1 mark for the correct final answer of \(0.48\) (accept with or without the unit \(\text{m/s}\)).

To find the mean velocity: 1. Sum the three readings: \(0.42 + 0.55 + 0.47 = 1.44\). 2. Divide the sum by the number of readings: \(1.44 \div 3 = 0.48\). The mean velocity is \(0.48\text{ m/s}\).

Award 1 mark for showing correct working, such as showing the addition of the three values and division by 3: \((0.42 + 0.55 + 0.47) \div 3\) or \(1.44 \div 3\). Award 1 mark for the correct final answer of \(0.48\) (accept with or without the unit \(\text{m/s}\)).

For (i), distance from the source is the independent variable plotted on the x-axis (18) and river depth is the dependent variable plotted on the y-axis (0.85), giving the coordinates (18, 0.85). For (ii), river depth increases downstream as more water enters the channel from tributaries, leading to a positive correlation.

1 mark for identifying correct coordinates: (18, 0.85) (accept 18, 0.85 without brackets). 1 mark for identifying positive correlation.

For (i), distance along the spit is plotted on the x-axis (120) and beach gradient is on the y-axis (8), which gives the coordinates (120, 8). For (ii), because beach gradient decreases as distance increases, the relationship is inverse, representing a negative correlation.

1 mark for the correct coordinates: (120, 8) (accept 120, 8 without brackets). 1 mark for identifying a negative correlation.

Systematic sampling involves selecting sample sites at regular, pre-determined intervals along a geographic transect. When investigating river channel characteristics downstream, this method is highly advantageous because: 1. It eliminates personal bias, as the researcher does not subjectively choose sites that are easier to access or look more interesting. 2. It ensures an even and consistent geographical coverage of the river from the upper to the lower course. 3. This consistency makes it easier to identify, plot, and analyze clear downstream trends, such as the gradual increase in channel width or decrease in bedload size, without leaving large gaps in the data.

Award 1 mark for identifying a valid advantage (e.g., eliminates subjectivity/bias, ensures even geographical coverage), plus 2 further marks for explaining how this is achieved and why it improves the investigation. Example: Systematic sampling removes researcher bias (1 mark) because sites are selected at regular, pre-determined intervals such as every 2 kilometres (1 mark). This ensures that all sections of the river are fairly represented, allowing downstream trends in channel characteristics to be accurately identified (1 mark).

When conducting a beach profile enquiry, students use a clinometer and ranging poles to measure slope angles. If they only measure at fixed distance intervals (for example, every 5 meters), they may miss significant micro-features on the beach. By measuring at every 'break of slope' (where the gradient visibly changes): 1. The profile captures precise topographical changes such as storm ridges, berms, or runnels. 2. The final plotted profile represents the actual, complex shape of the beach rather than a simplified, smoothed-out approximation. 3. This increases the accuracy of subsequent calculations, such as beach volume or cross-sectional area.

Award 1 mark for identifying how break-of-slope sampling captures topographical detail, and 2 further marks for explaining how this contrasts with fixed intervals to improve accuracy. Example: Measuring at every break of slope ensures that distinct beach features like berms or ridges are not missed (1 mark), which often occurs when using rigid, fixed-interval sampling (1 mark). Consequently, the plotted beach profile reflects the true shape and complexity of the beach gradient rather than a generalized average (1 mark).

Systematic sampling involves collecting data at regular, pre-determined intervals (for example, measuring river depth every 50 cm across a transect, or choosing study sites every 2 kilometres downstream).

Advantages of systematic sampling in this enquiry:
- It reduces researcher bias when selecting measurement locations, ensuring a more objective set of data.
- It is straightforward to plan, organize, and execute in the field, making efficient use of limited fieldwork time.
- It ensures that the entire width of the river channel or length of the river course is covered evenly, allowing clear trends (such as a velocity curve or downstream changes) to be identified.

Disadvantages of systematic sampling in this enquiry:
- It can miss key features or anomalies if they fall between the pre-determined sampling intervals (for example, missing the deepest point of a pool or a sudden change in bed roughness).
- Strict adherence to systematic intervals may be impossible or unsafe due to physical obstructions, deep/fast-flowing water, or lack of public access, requiring a shift to pragmatic sampling.
- It can lead to over- or under-representation of characteristics if there is a recurring pattern along the river that coincides with the sampling interval.

Conclusion:
Overall, systematic sampling is highly effective for measuring channel cross-sections (depth) because it guarantees an even profile. However, for downstream site selection, it must often be combined with pragmatic sampling to address safety and accessibility concerns while avoiding biased data.

Level 1 (1-3 marks):
- Demonstrates basic knowledge of systematic sampling.
- Simple, descriptive points with limited evaluation of its use in a river enquiry.
- Limited use of geographical terminology.

Level 2 (4-6 marks):
- Explains both advantages and disadvantages of systematic sampling within a river enquiry context (velocity/depth).
- Sound understanding of the method, showing some balance in the argument.
- Geographical terminology is used appropriately.

Level 3 (7-8 marks):
- Offers a detailed, balanced evaluation of systematic sampling, well-applied to the context of measuring velocity and depth.
- Reaches a logical and reasoned conclusion based on the evidence presented.
- Excellent use of geographical terminology throughout.

The secondary sector involves manufacturing and assembly. In Newly Industrialising Countries (NICs), the rapid growth of this sector is predominantly driven by foreign direct investment (FDI) and multinational corporations (MNCs) setting up manufacturing plants to benefit from lower labor costs and emerging markets.

1 mark for the correct answer B. 0 marks for any other option.

Counterurbanisation is the process of population movement from large urban areas to smaller rural settlements or villages. This is often driven by a desire for a better quality of life, cheaper housing, and improved transport links allowing commuting.

1 mark for the correct answer A. 0 marks for any other option.

An increase in the global population means more people are using household appliances, transportation, and infrastructure, all of which require energy. Alternatively, rapid industrialisation and economic development in emerging countries (like India or China) lead to a rise in factory production and higher standards of living, where more citizens can afford cars and air conditioning, thereby increasing energy demand.

Award 1 mark for identifying a valid reason, and a further 1 mark for development of the point up to a maximum of 2 marks. For example: Population growth (1 mark) leading to more domestic consumers using electricity and vehicles (1 mark). Or: Rising disposable incomes (1 mark) allowing more people to buy energy-consuming appliances like air conditioners (1 mark). Or: Industrialisation (1 mark) where expanding manufacturing sectors require substantial fuel and electricity inputs to run factories (1 mark).

Counter-urbanisation is the movement of people from urban areas to rural areas. One major pull factor is the desire for a higher quality of life, which rural areas offer through cleaner air, lower noise levels, safer neighborhoods, and larger properties with gardens. Another factor is the growth of remote working and improved transport links, allowing people to work from home or commute easily without needing to live in the city center.

Award 1 mark for identifying a valid reason, and a further 1 mark for development/explanation up to a maximum of 2 marks. For example: Quality of life factors (1 mark) such as wanting a safer, quieter, and less polluted environment for families (1 mark). Or: Technological changes (1 mark) enabling remote working/working from home, which reduces the need to live close to city offices (1 mark). Or: Transport improvements (1 mark) making commuting from distant villages more feasible and faster (1 mark). Or: High housing costs in cities (1 mark) driving buyers to rural areas where they can get larger properties for the same price (1 mark).

Farm diversification involves branching out from traditional farming activities into other areas, such as farm shops, tourism (e.g., campsites, holiday cottages), or leisure activities. Farmers do this to generate alternative sources of revenue, which provides financial security and stability when agricultural profits are low due to fluctuating crop prices, rising feed/fertiliser costs, or bad weather affecting harvests.

Award 1 mark for identifying a valid reason, and a further 1 mark for development of the point up to a maximum of 2 marks. For example: Fluctuation in farming income (1 mark) meaning alternative revenues are needed to buffer against bad harvest years or low market prices (1 mark). Or: Changing government subsidies (1 mark) forcing farmers to find new ways of surviving financially without reliance on direct agricultural support (1 mark). Or: Underutilised assets (1 mark) such as old barns which can be converted into profitable holiday lets or offices (1 mark).

Two reasons for the increasing global demand for energy are: 1) Global population growth: As the global population continues to rise, there are more people requiring energy for domestic use, such as cooking, heating, lighting, and powering appliances, which increases overall baseline consumption. 2) Economic development and rising living standards: As countries develop economically, particularly emerging economies, disposable incomes increase. This leads to a rise in consumerism, with more households purchasing energy-intensive goods such as air conditioning units, personal vehicles, and electronic devices, alongside expanded industrial factories requiring vast amounts of power.

Award 1 mark for each valid reason identified, and a further 1 mark for each reason developed (up to a maximum of 4 marks). Reason 1: Population growth (1), developed by explaining that more people means a greater total demand for basic domestic energy needs like cooking and lighting (1). Reason 2: Economic development or rising living standards (1), developed by explaining that as middle-class populations grow, they purchase more energy-consuming goods like cars or air conditioning (1). Reason 3: Rapid urbanisation (1), developed by explaining that moving to cities increases access to national power grids, boosting consumption (1).

Two environmental challenges caused by rapid urbanisation in LICs or NICs are: 1) Water pollution: Rapidly growing cities often outpace the development of municipal sewage systems and waste disposal infrastructure. As a result, untreated household sewage and chemical waste are dumped directly into local rivers, contaminating water supplies and damaging ecosystems. 2) Air pollution: The rapid increase in urban populations leads to a massive surge in vehicle ownership, often involving older, high-emitting vehicles, alongside unregulated industrial factories. This leads to severe air pollution and smog in urban areas, reducing air quality.

Award 1 mark for each valid environmental challenge identified, and a further 1 mark for each challenge developed/explained (up to a maximum of 4 marks). Challenge 1: Water pollution or contamination of water bodies (1), developed by explaining that waste management infrastructure cannot keep pace with population growth, leading to untreated waste dumped in rivers (1). Challenge 2: Air pollution or smog (1), developed by explaining that this is caused by a rapid rise in vehicles on congested roads and unregulated emissions from growing industries (1). Challenge 3: Loss of green spaces or habitat destruction (1), developed by explaining that urban sprawl leads to the clearing of surrounding forests and land to make way for housing (1).

High-tech or quaternary industries, such as biotechnology, software development, and aerospace engineering, have distinct locational requirements compared to traditional manufacturing.

Using Cambridge Science Park in the UK (a developed country) as a case study, several key factors influence where these industries locate:

1. Proximity to Universities and Research Centres: High-tech companies rely heavily on a highly skilled, specialized workforce. Cambridge Science Park is located adjacent to the University of Cambridge, providing firms with direct access to world-class graduates, researchers, and scientific breakthroughs.

2. Transport Connectivity: Global and domestic connectivity is vital for high-tech industries to move specialized components, access markets, and facilitate business travel. The Science Park is located directly off the M11 motorway, providing fast road access to London, and is close to London Stansted Airport, enabling international travel.

3. Agglomeration and Clustering: High-tech industries benefit from locating near similar firms (agglomeration). At Cambridge, over 100 businesses are clustered together. This creates a dense network of shared ideas (knowledge spillover), attracts specialized support services (like venture capitalists and intellectual property lawyers), and fosters a local pool of specialized labor.

4. Attractive, High-Quality Environment: Highly qualified professionals are internationally mobile and seek a high quality of life. The Science Park offers a landscaped, greenfield site with lakes, cycle paths, and modern architectural spaces, which helps companies recruit and retain top-tier talent.

In conclusion, the location of quaternary industries is heavily dependent on human, physical, and financial capital infrastructure, specifically access to elite knowledge hubs, rapid transport networks, and an attractive working environment.

Level Descriptors:

Level 1 (1–3 marks):
- Demonstrates isolated elements of geographical knowledge and understanding of quaternary/high-tech industry location.
- Explains only one or two factors in a generic way (e.g., 'they need workers' or 'they need roads').
- No specific developed country or case study is named, or the reference is highly superficial.

Level 2 (4–6 marks):
- Demonstrates clear geographical knowledge and understanding of several locational factors.
- Explains how these factors (such as university links, transport, and agglomeration) attract high-tech firms.
- A named HIC or specific location (e.g., Cambridge Science Park, Silicon Valley) is used, with some specific detail linked to the factors, though the analysis may be unbalanced.

Level 3 (7–8 marks):
- Demonstrates precise, detailed geographical knowledge and understanding of a range of locational factors.
- Offers a well-structured, logical analysis showing how these factors interact to influence location decisions.
- Fully integrates a relevant, detailed case study from a named HIC (e.g., Cambridge Science Park) to support all points made.

Systematic sampling involves choosing sites at regular intervals (e.g., every 100 metres). The main disadvantage of this method is that it can miss significant changes or localized features (such as a small park or a heavily polluted junction) that fall between the designated sampling points.

Award 1 mark for any valid disadvantage: - It can miss key variations/features between the sampling points (1). - It may introduce bias if the sampling interval coincides with a regular pattern in the urban environment (e.g., street blocks) (1). - It is less flexible if a chosen point is inaccessible (1). Do not accept: 'It is biased' without further explanation.

A primary data collection method to find a retail development's sphere of influence is a questionnaire or postcode survey. By asking shoppers where they have travelled from (e.g., their postcode or settlement of origin), researchers can map the catchment area or sphere of influence.

Award 1 mark for any valid primary data collection method: - Questionnaire/survey asking shoppers where they live/their postcode (1). - Pedestrian interviews about travel distance/time (1). Reject: 'Traffic count' or secondary data sources (e.g., census data).

To find the percentage of residents working in the tertiary sector:
1. Identify the number of residents in the tertiary sector: 93
2. Identify the total number of surveyed residents: 150
3. Calculate the percentage: \(\frac{93}{150} \times 100 = 0.62 \times 100 = 62\\%\)

Therefore, the percentage of residents surveyed who work in the tertiary sector is 62%.

Award 1 mark for showing a correct method (working):
- \(\frac{93}{150} \times 100\) or equivalent (e.g. \(0.62 \times 100\) or \(\frac{31}{50}\))

Award 1 mark for the correct final answer:
- 62 (%)

Note: Award full 2 marks for a correct final answer of 62 (%) even if no working is shown.

To complete the scatter graph: 1. Locate \(1.2\) km on the horizontal x-axis (Distance from CBD). 2. Move vertically to find the value of \(12\) on the vertical y-axis (EQI Score) and plot a clear cross (x) or dot at this intersection. 3. Draw a straight line of best fit that slopes downwards from the top-left to the bottom-right (reflecting a negative correlation), ensuring an approximately equal number of data points lie on either side of the line.

Award 1 mark for plotting the data point for Site 8 accurately at \(1.2\) km on the x-axis and \(12\) on the y-axis (allow tolerance of +/- \(0.1\) km and +/- \(0.5\) EQI score). Award 1 mark for drawing a suitable straight line of best fit showing a negative correlation, passing centrally through the main body of plotted points.

To complete the scatter graph: 1. Find \(18\) km on the horizontal x-axis (Distance traveled). 2. Move vertically up to \(22\) on the vertical y-axis (Hourly wage) and mark the point with a clear cross (x) or dot. 3. Draw a straight line of best fit that slopes upwards from the bottom-left to the top-right (reflecting a positive correlation), balanced so that there is an equal distribution of points above and below the line.

Award 1 mark for plotting the data point for Employee G accurately at \(18\) km on the x-axis and \(22\) on the y-axis (allow tolerance of +/- \(1\) km and +/- \(1\) £). Award 1 mark for drawing a suitable straight line of best fit showing a positive correlation, passing centrally through the distribution of plotted points.

Systematic sampling involves selecting sites at regular intervals (for example, every 150 metres along a transect from the CBD). Award 1 mark for identifying an advantage, and a further 2 marks for explanation/development: It removes researcher bias in selecting sites (1 mark) because the locations are pre-determined by a fixed interval rather than personal choice (1 mark), which means the collected data is more representative and objective, improving the reliability of the geographical enquiry (1 mark).

Award 1 mark for an advantage, and up to 2 further marks for development/explanation of how this assists the enquiry (maximum of 3 marks): Removes researcher bias / objective selection (1 mark); Sites are selected at regular, pre-determined intervals (e.g. every 100m) (1 mark); Ensures the whole area/transect is covered fairly / increases representativeness / reliability of conclusions (1 mark).

A scatter graph is used to display the relationship between two sets of continuous data (bivariate data). Award 1 mark for identifying why a scatter graph is appropriate, and a further 2 marks for explanation/development: It allows for the visual identification of a correlation or relationship between two continuous variables (1 mark) because both distance from the CBD and environmental quality score are continuous numerical scales (1 mark). This enables the researcher to easily draw a line of best fit to determine the strength and direction of the relationship (1 mark).

Award 1 mark for a valid reason, and up to 2 further marks for development/explanation (maximum of 3 marks): Shows correlation/relationship between two continuous variables (1 mark); Allows the researcher to easily see if environmental quality changes as distance from the CBD increases (e.g., positive or negative trend) (1 mark); Enables the identification of anomalies / allows a line of best fit to be drawn to test the hypothesis (1 mark).

### Model Answer

**Enquiry Aim:** To investigate how environmental quality and land-use change with distance from the Central Business District (CBD) in Town X.

**Introduction**
To investigate the variations in urban quality of life and land-use patterns across Town X, we used two main primary data collection methods: an Environmental Quality Survey (EQS) and pedestrian footfall counts. While both methods successfully provided quantitative data to analyze urban gradients, their effectiveness varied due to issues of subjectivity and temporal limitations.

**Evaluation of Method 1: Environmental Quality Survey (EQS)**
The EQS was highly effective for gathering spatial data quickly. We selected 10 sites along a transect starting from the CBD and moving outwards to the suburbs. At each site, we assessed factors such as noise levels, litter, and building maintenance on a bipolar scale of -3 to +3. This provided immediate numerical data that was easy to plot on scatter graphs and compare. However, the main limitation of the EQS was its high subjectivity. Different group members had varying perceptions of what constituted a 'littered' or 'noisy' street, which reduced the internal reliability of the data. To improve effectiveness next time, we should have carried out a pilot study together to calibrate our scoring criteria or calculated a mean score from several independent student evaluations at each site.

**Evaluation of Method 2: Pedestrian Footfall Counts**
To assess urban vitality and change along the transect, we conducted 5-minute pedestrian counts at each of the 10 sites. This quantitative method was objective, simple to implement, and provided direct evidence of urban density and activity. However, a major weakness was that the counts represented only a brief 'snapshot' in time (taken between 11:00 AM and 12:30 PM on a Tuesday). Footfall levels fluctuate dramatically depending on the time of day, day of the week, and prevailing weather conditions. For example, a count taken during rush hour or on a Saturday would yield completely different results, meaning our data had low temporal reliability.

**Evaluation of Sampling Strategy**
We used systematic sampling, choosing a site every 300 meters along our transect. This ensured a fair, unbiased coverage of the urban area. However, this rigid sampling interval occasionally forced us to collect data in atypical locations (e.g., right next to a temporary construction site), which temporarily distorted our EQS and footfall results.

**Conclusion**
In conclusion, the primary data collection methods were moderately effective. They allowed us to identify clear spatial trends, showing that environmental quality generally improved while pedestrian density decreased with distance from the CBD. However, their overall reliability was compromised by the subjectivity of the EQS and the temporal limitations of the pedestrian count. To achieve a highly reliable set of findings, these methods should be repeated at different times of day and supplemented with secondary datasets, such as census tract data on income levels.

### Marking Scheme

**Level 1 (1–3 marks): Describing and basic understanding**
* Demonstrates isolated knowledge of geographical enquiry.
* Identifies one or more primary data collection methods (e.g., questionnaires, pedestrian counts, EQS) but descriptions are generic and lack specific application to their own enquiry.
* There is little or no evaluation of effectiveness or reliability.
* Direct answers or structural progression are weak.

**Level 2 (4–6 marks): Explaining and partial evaluation**
* Demonstrates good geographical knowledge and understanding of human fieldwork techniques.
* Applies knowledge to explain how the primary data collection was carried out in their specific enquiry.
* Evaluates the methods, presenting some strengths and limitations (e.g., subjectivity, sample size, or timing), but the evaluation may be unbalanced or lack depth.
* Offers a partially supported conclusion regarding the overall effectiveness of the methods.

**Level 3 (7–8 marks): Critical evaluation**
* Demonstrates precise, detailed geographical knowledge of human fieldwork methodologies, sampling strategies, and data reliability.
* Critically evaluates the effectiveness of primary methods, clearly weighing up advantages against limitations (such as bias, subjectivity, temporal/spatial constraints).
* Comments on how sampling techniques (e.g., systematic, random, stratified) affected the validity of the results.
* Provides a well-substantiated and balanced judgment/conclusion that directly assesses how successful the methods were in meeting the enquiry's overall aim.

One natural cause of climate change is volcanic eruptions, which release large amounts of greenhouse gases such as carbon dioxide, or aerosols that reflect solar radiation.

Award 1 mark for any valid natural cause of climate change, such as: Volcanic activity, Milankovitch cycles (orbital changes), or Solar output variation. Do not accept human-induced factors.

A remittance is the transfer of money, goods, or other assets by a migrant worker back to their family or community in their home country.

Award 1 mark for a clear definition showing that money is transferred by migrants/workers back to their home country.

One social indicator of development is the literacy rate, which reflects the percentage of the population over a certain age who can read and write.

Award 1 mark for a valid social indicator, such as: Literacy rate, Life expectancy, Infant mortality rate, or Access to clean water. Reject economic indicators such as GDP or GNI.

Two human activities contributing to desertification are:

1. Overcultivation: This occurs when land is repeatedly used to grow crops without adequate fallow periods (1). This exhausts the soil nutrients, leading to a loss of vegetation cover and making the dry, degraded soil highly vulnerable to wind and water erosion (1).

2. Overgrazing: This happens when too many farm animals are kept on a piece of land, eating vegetation faster than it can naturally regenerate (1). This strips the land of protective vegetation cover, and the animals' hooves compact the soil, reducing water infiltration and preventing future plant growth (1).

For each of the two human activities explained:
- Award 1 mark for identifying a valid human activity (e.g., overgrazing, overcultivation, deforestation, unsustainable irrigation).
- Award 1 additional mark for explaining how this activity leads to soil degradation/desertification.

Example marking pathway:
- Overgrazing (1 mark) + leads to livestock stripping the vegetation cover, which exposes soil to wind erosion (1 mark).
- Deforestation for fuelwood (1 mark) + removes root systems that bind the soil together, making it easier for wind/rain to wash topsoil away (1 mark).

Two ways ICT has accelerated globalisation are:

1. Instant global communications and financial transactions: The development of high-speed internet, fibre-optic cables, and mobile networks allows businesses to transfer vast amounts of capital and data instantly across borders (1). This enables Transnational Corporations (TNCs) to coordinate complex global supply chains and outsource services to other countries in real time (1).

2. Rapid spread of global culture and media: Social media platforms and online streaming services allow people worldwide to access and share cultural products, news, and trends instantaneously (1). This creates a highly interconnected 'global village' where consumer tastes, fashions, and ideas become shared globally, breaking down geographic barriers (1).

For each of the two ways explained:
- Award 1 mark for identifying a relevant aspect of ICT development (e.g., internet, mobile technology, satellite communications, social media, online banking).
- Award 1 additional mark for explaining how this has accelerated the integration of people, businesses, or countries (globalisation).

Example marking pathway:
- High-speed internet and email (1 mark) + allow TNCs to communicate instantly with offshore offices, enabling efficient global outsourcing (1 mark).
- Social media and streaming platforms (1 mark) + facilitate the global transmission of cultural trends and ideas, leading to cultural convergence (1 mark).

An exemplary response should include:
- **Analysis of trends in Table 1**: Average annual rainfall decreased significantly by 130 mm (from 450 mm in 1990 to 320 mm in 2020). This corresponds directly with a severe loss of vegetation cover (falling from 42% to 15%) and a dramatic expansion of active sand dunes, which more than tripled from 110 km² to 380 km².
- **Explanation of physical processes**: Reduced rainfall decreases soil moisture. Without sufficient water, vegetation dies back, as evidenced by the 27% drop in vegetation cover. The absence of plant roots leaves the topsoil loose and vulnerable to wind erosion, accelerating the mobilization of sand dunes (which expanded by 270 km² over the 30-year period).
- **Integration of own knowledge (human factors)**: Human activities such as overgrazing, overcultivation, and deforestation for fuelwood further strip the land of vegetation. As the population in these fragile areas grows, these pressures intensify, creating a positive feedback loop of desertification where dry soils are easily eroded and converted into desert.

**Level 1 (1–2 marks) - Basic**
- Identifies basic trends from Table 1 (e.g., rainfall is decreasing, dunes are increasing).
- Demonstrates isolated knowledge of desertification with limited explanation.
- Simple, descriptive language with limited geographical terminology.

**Level 2 (3–4 marks) - Clear**
- Explains the connection between different variables in the data (e.g., link between falling rainfall, reduced vegetation, and dune growth).
- Incorporates some geographical knowledge of human or physical causes of desertification (e.g., overgrazing or soil erosion).
- Uses appropriate geographical terminology.

**Level 3 (5–6 marks) - Detailed**
- Offers a balanced, well-developed analysis using specific data points from Table 1 to support the argument.
- Explains the multi-causal nature of desertification, showing how physical factors (decreasing rainfall trends) interact with human pressures (such as overcultivation or fuelwood collection) to degrade fragile environments.
- Well-structured explanation with precise use of geographical terms.

Case study: The Sahel region of Africa. Local-scale (bottom-up) strategies include 'magic stones' (stone lines or bunds) and Zai pits. In Burkina Faso, stone bunds are built along contour lines to slow down surface runoff, allowing water to infiltrate the soil and trapping nutrient-rich topsoil. This cheap, community-led method has successfully restored degraded land and increased crop yields by up to 50 percent. Similarly, Zai pits trap water and organic matter, utilizing termites to naturally aerate the soil. These local, bottom-up strategies are highly successful because they require no expensive technology, are easily maintained by local farmers, and are highly sustainable. In contrast, large-scale (top-down) strategies like the Great Green Wall (GGW) initiative aim to plant an 8,000 km wide band of trees across the entire width of Africa to halt the southward expansion of the Sahara. While the GGW has massive potential to restore 100 million hectares of land and sequester carbon, its success has been highly uneven. It is limited by political instability in countries like Mali and Chad, a lack of long-term funding, and low survival rates of tree saplings when local communities are not actively involved in their upkeep. In conclusion, while large-scale regional projects offer an important long-term vision, local bottom-up strategies are currently far more successful and reliable due to their low cost, high community ownership, and immediate positive impacts on local food security.

AO2 (6 marks): Candidates demonstrate knowledge and understanding of the processes of desertification and the specific management strategies (both local/bottom-up and national/top-down) used in a named fragile environment. AO3 (6 marks): Candidates evaluate the success of these strategies, comparing their cost-effectiveness, environmental sustainability, social acceptability, and overall impact, leading to a balanced and well-supported judgment. Level 1 (1-4 marks): Simple, generic description of one or two desertification strategies. Lacks a named case study or uses it only nominally. No evaluation or very basic assertions of success. Level 2 (5-8 marks): Explains some specific strategies with reference to a named fragile environment (e.g. Sahel). Some attempt to evaluate the success of local versus large-scale strategies, but may lack balance or depth. Level 3 (9-12 marks): Comprehensive and detailed evaluation of multiple strategies in a clearly identified fragile environment. Offers a balanced argument weighing the strengths and limitations of both local/bottom-up and national/top-down strategies. Reaches a clear, logical, and fully justified concluding judgment.