2024 HKDSE Geography Answers & Marking Scheme

Destructive plate boundaries typically feature felsic/andesitic magma which has a higher silica content (1) and high viscosity. This high viscosity traps gases, building up immense pressure (3) before erupting explosively. In contrast, constructive boundary magma (basaltic) actually has a higher temperature (about 1000–1200°C) than destructive boundary magma (about 800–1000°C), making statement 2 incorrect.

Award 1 mark for selecting B. Option B correctly identifies that statements 1 and 3 are correct, while statement 2 is incorrect because destructive boundary lava has a lower temperature than constructive boundary lava.

As a river flows downstream, although the gradient decreases, the channel becomes much larger, smoother (decreasing channel roughness, so statement 2 is incorrect), and more efficient (higher hydraulic radius, statement 3 is correct). This reduction in friction causes the average velocity of the river to increase downstream (statement 1 is correct).

Award 1 mark for selecting B. Statements 1 and 3 are correct geographic trends, while statement 2 is incorrect as channel roughness decreases downstream.

Silicon Valley offers strong agglomeration economies, featuring a cluster of high-tech firms, research institutions, and venture capital, which are vital for R&D. Conversely, microchip assembly is a labor-intensive, lower-value-added process that seeks regions with abundant, low-cost labor (such as Southeast Asia) to minimize production costs.

Award 1 mark for B. The option correctly matches the high-value R&D stage with agglomeration economies and the assembly stage with low labor costs.

In tropical rainforests, high temperature and humidity promote rapid decomposition (1). Nutrients released are immediately absorbed by the extensive root networks of the dense vegetation (3). Any remaining soluble nutrients are quickly washed away deep into the soil profile by high precipitation (leaching) (2). Therefore, nutrients are stored mainly in the biomass rather than the soil, making all three statements correct.

Award 1 mark for D. All three statements correctly identify the core reasons for the nutrient-poor status of tropical rainforest soils.

A positive feedback loop amplifies the initial change. In option C, warming melts ice, which decreases the earth's albedo (reflectivity). Less reflection means more solar energy is absorbed by the dark ocean, leading to higher temperatures and further melting. Options A, B, and D describe negative feedback loops that tend to counteract or self-regulate the warming trend.

Award 1 mark for C. Only option C represents a positive feedback mechanism where the response amplifies the warming effect.

Groynes are hard engineering structures built perpendicular to the shore to trap sand moved by longshore drift. Sediment accumulates on the updrift side of the groyne, but because the sediment supply is blocked, the downdrift side is starved of sand and experiences accelerated erosion.

Award 1 mark for A. The answer correctly describes the asymmetric deposition and erosion patterns caused by groynes interrupting longshore drift.

Push factors are negative circumstances that force people to leave their origin. In rural villages of developing countries, rural overpopulation, lack of arable land, and limited employment opportunities are primary push factors. Options A is an urban push factor, B is not a primary factor, and D represents a facilitating pull/infrastructure factor.

Award 1 mark for C. The option correctly identifies a rural push factor that drives rural-to-urban migration.

The Sahel region has a semi-arid climate characterized by highly variable, unreliable rainfall and frequent droughts (physical factor). Human activities such as overgrazing and deforestation lead to desertification and severe land degradation, drastically reducing food production.

Award 1 mark for B. Correctly identifies the Sahel's specific physical vulnerability (rainfall variability) and corresponding destructive human practice (overgrazing).

REDD+ is an international climate initiative created by the UNFCCC. It provides financial incentives to developing countries to manage their forests sustainably and avoid deforestation. The payments are calculated based on verified reductions in greenhouse gas emissions compared to a historic baseline.

Award 1 mark for C. The option correctly identifies the market-based financial incentive mechanism of the REDD+ program.

First, calculate the actual horizontal distance:
\text{Ground Distance} = 6.5\text{ cm} \times 20,000 = 130,000\text{ cm} = 1,300\text{ m}.
Next, compute the gradient using the formula:
\text{Gradient} = \frac{\text{Vertical Rise}}{\text{Horizontal Distance}} = \frac{130\text{ m}}{1,300\text{ m}} = \frac{1}{10} = 1:10.

Award 1 mark for B. Calculations: 6.5 cm translates to 1,300 m on the ground. Rise/Run = 130/1300 = 1:10.

P-waves (primary waves) can travel through solids, liquids, and gases, whereas S-waves (secondary waves) can only travel through solids. S-waves are slower than P-waves. S-waves are transverse waves that vibrate perpendicular to the propagation direction. Love waves are surface waves, not body waves (P-waves and S-waves are body waves). Thus, statements (1) and (3) are correct.

Award 1 mark for the correct answer A. No marks for other options.

Downstream, the channel becomes wider and deeper, increasing the hydraulic radius and efficiency. Although the gradient decreases, the average velocity increases because of a large reduction in friction caused by a smoother bed (less channel roughness) and a greater volume of water.

Award 1 mark for the correct answer B. No marks for other options.

High-tech industries like microchip manufacturing are footloose but highly dependent on agglomeration economies near universities/research centers for R&D talent, and international airports for rapid air freight of lightweight, high-value products.

Award 1 mark for the correct answer B. No marks for other options.

In tropical rainforests, most nutrients are stored in the biomass (living vegetation) because of the dense forest structure. Rapid decomposition leads to a very small litter pool, and swift plant uptake leaves very few nutrients in the soil pool.

Award 1 mark for the correct answer C. No marks for other options.

Mitigation strategies aim to reduce the sources or enhance the sinks of greenhouse gases (Options A, C, D). Adaptation strategies aim to adjust natural or human systems to minimize the harmful impacts of climate change (Option B).

Award 1 mark for the correct answer B. No marks for other options.

Wave refraction bends waves towards headlands, concentrating energy there and causing erosion. In bays, wave crests diverge, dispersing energy and promoting deposition. This process eventually straightens the coastline as headlands retreat and bays fill up with sediment. Headlands do not widen.

Award 1 mark for the correct answer A. No marks for other options.

Map distance = \(5\text{ cm}\). Real-world horizontal distance = \(5\text{ cm} \times 20\ 000 = 100\ 000\text{ cm} = 1000\text{ m}\). Vertical height difference = \(320\text{ m} - 120\text{ m} = 200\text{ m}\). Average gradient = \(200\text{ m} / 1000\text{ m} = 1/5\) or \(1\text{ to }5\).

Award 1 mark for the correct answer A. No marks for other options.

Statements (1), (2), and (3) are natural/physical geographical factors that lead to food shortages. Statement (4) is a human activity/factor, and thus should be excluded from the category of physical factors.

Award 1 mark for the correct answer C. No marks for other options.

Rehabilitation focuses on upgrading and repairing older buildings to prevent decay, whereas redevelopment involves tearing them down. Preservation protects heritage sites, and revitalisation breathes new life into historical buildings or districts for new uses.

Award 1 mark for the correct answer B. No marks for other options.

All statements are correct. Inland iron ore resources are depleting or of low grade. Steel producers now rely heavily on imported raw materials. Locating plants at deep-water coastal ports allows massive bulk carriers to deliver materials directly, minimizing expensive domestic overland transport.

Award 1 mark for the correct answer D. No marks for other options.

Part (a): An acceptable hypothesis could be: 'The redeveloped urban green district (District X) has a lower air temperature and higher wind speed than the old high-density district (District Y).'

Part (b): To ensure reliability, students should conduct systematic sampling at multiple points within each district, and repeat measurements at least 3 times at each point to calculate an average, minimizing random errors. To ensure accuracy, they must use calibrated digital instruments (e.g., anemometer, thermohygrometer), hold instruments away from body heat/obstructions, measure at a standard height (e.g., 1.5 meters above ground), and take synchronized readings across both districts to eliminate temporal variations.

Part (c): District X has a lower mean air temperature (31.5C) than District Y (34.2C), showing a difference of 2.7C. District X has a higher relative humidity (65%) compared to District Y (55%). District X experiences much stronger wind conditions (2.4 m/s) compared to the near-calm conditions in District Y (0.5 m/s). Lastly, District X has a significantly larger Sky View Factor (0.62) than District Y (0.21).

Part (d): The urban design of District X includes more green spaces and vegetation which promotes evapotranspiration, lowering the air temperature and raising relative humidity. The larger Sky View Factor (0.62) in District X means wider street canyons and lower building density, allowing longwave radiation to escape easily into the atmosphere, reducing heat trapping. In contrast, District Y has narrow street canyons (SVF of 0.21) causing a severe urban canyon effect. District X likely incorporates planned wind corridors aligned with prevailing winds, allowing high wind speeds (2.4 m/s) to disperse heat, whereas District Y's high building density blocks air flows (0.5 m/s).

Part (e): Limitations and improvements: (1) Single afternoon data does not represent seasonal or diurnal changes. Improvement: Repeat fieldwork in different seasons (winter) or times of day (night-time). (2) Weather anomalies on that specific afternoon may skew results. Improvement: Check weather forecasts and conduct fieldwork on multiple days with similar sunny conditions. (3) Spatial coverage may be insufficient. Improvement: Increase the number of sampling points and use GIS mapping to plot microclimate variations.

Part (a): [Total: 1 mark] Award 1 mark for a clear, testable, and geographical hypothesis showing a relationship between variables/locations.
Part (b): [Total: 5 marks] Max 3 marks for reliability (sampling, repetitions, averages). Max 3 marks for accuracy (instrument calibration, standardized height, synoptic/synchronized measurement, avoiding heat bias). Must cover both aspects for full marks.
Part (c): [Total: 4 marks] Award 1 mark for each correct comparison with data support (temperature, relative humidity, wind speed, SVF). Mentioning the exact values or differences is required for the data support mark.
Part (d): [Total: 5 marks] Award marks for explaining: Evapotranspiration of green spaces (1 mark); SVF and longwave radiation escape vs trapping in narrow canyons (2 marks); Building density/height and wind corridors blocking or encouraging air flow (2 marks).
Part (e): [Total: 3 marks] Award 1 mark for each matching pair of limitation and improvement (up to 3 pairs). Deduct marks if the improvement does not directly address the identified limitation.

Part (a): In Settlement A, economic opportunities are primarily agricultural and nature-dependent. Volcanoes provide fertile volcanic soil (rich in minerals like phosphorus and potassium) that supports high-yield subsistence farming. In contrast, Settlement B capitalizes on high-value technology and service industries. It utilizes high-temperature geothermal energy for electricity generation and heating, and attracts high-income tourism through hot springs, geological parks, and educational tours.

Part (b): Socio-economic factors increasing Settlement A's vulnerability include: (1) Low income and dependence on subsistence farming mean residents cannot afford to relocate or buy insurance. (2) Low literacy rates limit public understanding of scientific hazard warnings and evacuation drills. (3) Poor infrastructure (lack of paved roads and emergency vehicles) slows down evacuation when an eruption occurs. (4) Weak local governance and lack of fiscal resources mean there are no concrete hazard maps, sirens, or temporary shelters built.

Part (c): Settlement B reduces risk through: (1) Advanced monitoring technology, such as seismometers, tiltmeters, and GPS to track magma movements and ground deformation for early warnings. (2) Strict land-use zoning that bans high-density residential developments in high-risk lava flow zones. (3) Well-planned infrastructure including volcanic debris dams (sabo dams) to redirect lahars, and clearly marked evacuation routes with regular community-wide drills.

Part (d): To a small extent / To a large extent / It depends on the capacity to cope. For Settlement A, it might seem irrational due to high casualty risk, but poor farmers have no alternative livelihood or land, making it a forced choice rather than an irrational one (the soil fertility outweighs the perceived sporadic risk). For Settlement B, living there is highly rational because the economic benefits (geothermal energy, tourism revenue) are continuous, and the advanced prediction and mitigation measures reduce the physical risk to an acceptable minimum.

Part (a): [Total: 4 marks] Award 2 marks for explaining Settlement A's opportunities (agriculture, soil fertility, mineral extraction). Award 2 marks for explaining Settlement B's opportunities (geothermal energy, tourism, advanced research).
Part (b): [Total: 6 marks] Award up to 6 marks (max 3 points with explanation) for linking socio-economic factors to vulnerability: agricultural dependency/poverty (2 marks), low literacy/poor education on warnings (2 marks), poor transport infrastructure (2 marks), and weak governance/fiscal constraints (2 marks).
Part (c): [Total: 4 marks] Award 2 marks for technical monitoring methods (instruments and warnings). Award 2 marks for administrative/planning aspects (zoning, sabo dams, evacuation planning, public drills).
Part (d): [Total: 4 marks] Candidates should express a clear stance. Award up to 2 marks for discussing the 'forced rationality' of Settlement A (resource attraction vs risk tolerance). Award up to 2 marks for discussing the 'managed risk' of Settlement B (cost-benefit balancing). Maximum 3 marks if only one settlement is discussed.

Part (a): Beach erosion is primarily caused by destructive waves, which have a high frequency, steep wave height, a weak swash, and a strong backwash that combs sediment off the beach. Additionally, longshore drift (caused by waves approaching the coast at an oblique angle) transports sediment away from the bay. If the sediment input into the bay is less than the sediment output transported away, net erosion occurs.

Part (b): [For the diagram, candidates should draw/describe: A shoreline with waves approaching at an oblique angle, groynes built perpendicular to the coast, sediment accumulating on the updrift side of the groynes, and an eroded beach on the downdrift side]. Groynes are barriers built perpendicular to the shore. They trap sediment transported by longshore drift on the updrift side, widening the beach. However, they block sediment from reaching the downdrift side. Deprived of sediment supply, the downdrift beach continues to experience erosion by waves, leading to accelerated erosion (terminal groyne syndrome).

Part (c): Environmental sustainability: Scheme P (hard engineering) disrupts the natural coastal dynamic, destroys coastal habitats, and causes visual pollution, making it unsustainable. Scheme Q (soft engineering) maintains the natural appearance of the sandy beach, preserves habitats, and allows the coast to dynamically adjust to sea-level rise, offering higher sustainability. Cost-effectiveness: Scheme P has very high initial construction costs but lower routine maintenance. However, it may cause expensive downstream damage. Scheme Q has lower initial costs but requires continuous, expensive re-nourishment over time as waves continue to wash imported sand away.

Part (d): Scheme Q is more appropriate for a high-end tourist resort. High-end tourists value natural aesthetic beauty, sandy beaches, and recreational space. Scheme P destroys the natural beach landscape with ugly concrete walls and groynes, reducing recreational space. Scheme Q preserves the natural, wide sandy beach. Although Scheme Q requires continuous maintenance and limits development in the 50m setback zone, this setback zone can be landscaped as a green park, enhancing the resort's premium ecological image.

Part (a): [Total: 4 marks] Award 2 marks for explaining destructive wave characteristics (frequency, swash/backwash dominance). Award 2 marks for explaining transport processes (longshore drift oblique angle, sediment budget deficit).
Part (b): [Total: 5 marks] Diagram: 1 mark for clear labels of longshore drift, groyne, sediment accumulation, and downdrift erosion. Text explanation: 2 marks for explaining how groynes trap sediment to protect the beach. 2 marks for explaining the blockage of sediment transport causing downdrift starvation and erosion.
Part (c): [Total: 5 marks] Sustainability (max 3 marks): Contrast hard vs soft engineering impact on coastal ecology, landscape aesthetics, and dynamic equilibrium. Cost-effectiveness (max 3 marks): Compare initial capital vs recurring maintenance costs, including downstream damage costs.
Part (d): [Total: 4 marks] Clearly state preference for Scheme Q (or Scheme P with strong justification) (1 mark). Provide 3 marks of justification focusing on tourist perception, beach usability, natural landscape value, and the zoning benefits (setback zone as recreational/green buffer).

Part 1: Impact of agricultural activities and deforestation (6 marks)\n- Deforestation reduces vegetation cover, leading to decreased interception. Direct throughfall and stemflow increase.\n- Without tree roots and organic matter, soil infiltration capacity decreases, resulting in less groundwater recharge and higher surface runoff (overland flow).\n- Agricultural practices (e.g., tillage, use of heavy machinery, overgrazing) compact the soil, further reducing infiltration and accelerating surface runoff.\n- Consequently, the lag time of the river basin is shortened. Peak discharge increases significantly and occurs much sooner after heavy rainfall.\n- Deforestation and farming expose bare soil to water erosion. Eroded soil is carried downstream as load and deposited in the lower course of the river (silting).\n- Riverbed aggradation reduces the bankfull capacity (carrying capacity) of the channel, making the lower course highly susceptible to flooding during heavy rain.\n\nPart 2: Evaluation of soft measures vs hard engineering (6 marks)\nArguments supporting the statement (Strengths of soft measures / Limitations of hard engineering):\n- Soft measures like afforestation tackle the root cause of flooding by regulating the hydrological cycle (increasing infiltration and basin lag time) and restoring natural ecosystem services.\n- Land use regulation (e.g., flood hazard zoning) prevents high-value development in floodplains, directly minimizing potential economic losses and risk to human lives.\n- Hard engineering (e.g., channelization, dykes, dams) is highly disruptive to ecosystems, destroying river habitats and potentially transferring flood risks downstream.\n- Hard engineering requires high capital investment and continuous maintenance, and might fail catastrophically during extreme events exceeding design capacities.\n\nArguments against the statement (Limitations of soft measures / Strengths of hard engineering):\n- Soft measures require huge land areas, which may conflict with agriculture or urban growth. Afforestation also takes decades to mature and become effective.\n- Land use zoning does not physically reduce floodwater volume and faces strong political/economic resistance from landowners.\n- Hard engineering measures offer immediate, highly reliable, and localized flood protection, which is essential for protecting densely populated urban areas where land is scarce and expensive.\n\nConclusion:\n- Agree to a large extent. Soft measures are more ecologically sustainable and cost-effective in the long run. However, an integrated river basin management (IRBM) approach combining both soft and hard measures is the most pragmatic solution.

Part 1 (Max 6 marks):\n- Award 1 mark for each well-explained point on hydrological process change (e.g., reduced interception, decreased infiltration, increased overland flow, shortened lag time, increased peak discharge).\n- Award 1-2 marks for explaining soil erosion and downstream channel silting leading to reduced channel capacity.\n\nPart 2 (Max 6 marks):\n- Marks are awarded based on the depth of evaluation and balanced argument.\n- Level 3 (5-6 marks): Comprehensive discussion of both soft measures (strengths and limitations) and hard engineering (strengths and limitations). Formulates a clear, well-reasoned stance (e.g., to a large extent) and integrates concepts of environmental and social sustainability.\n- Level 2 (3-4 marks): Explains some advantages/disadvantages of both measures but lacks depth or balance. The evaluation is general and lacks specific geographical terms.\n- Level 1 (1-2 marks): Brief listing of some flood control methods. Little or no evaluation/comparison.

(a)
- Greenery coverage in District Y (41%) is more than three times higher than that in District X (12%).
- Average surface albedo is much higher in District Y (0.35) than in District X (0.15).
- The runoff coefficient in District Y is much lower (0.30) compared to District X (0.85), indicating better stormwater retention and natural infiltration.
- Air quality is better in District Y with a lower average \(PM_{2.5}\) concentration (22 \(\mu g/m^3\)) compared to District X (38 \(\mu g/m^3\)).
- Overall, District Y demonstrates vastly superior environmental performance compared to District X.

(b)
- **Greenery coverage (transpiration & shading):** District Y's higher greenery coverage (41% vs 12%) means extensive plant and canopy cover. Plants undergo transpiration, absorbing latent heat and cooling the surrounding microclimate. Shading from trees prevents solar radiation from directly heating concrete pavements and building facades, reducing heat storage during the daytime.
- **Surface Albedo (reflection of solar radiation):** The higher surface albedo in District Y (0.35 vs 0.15) indicates the use of lighter-coloured, highly reflective building and paving materials. This reflects a larger proportion of shortwave solar radiation back to space, reducing the absorption of solar energy and lowering the amount of heat re-radiated as longwave thermal radiation at night.

(c)
- **Physical challenges:**
- *High-density urban layout and lack of space:* Old districts in Hong Kong (e.g., Sham Shui Po, To Kwa Wan) feature narrow streets and extremely high building density. This leaves negligible ground-level space for street greening or porous pavement construction.
- *Structural constraints of old buildings:* Many old buildings (such as 'tong laus') have compromised structural integrity and lack the load-bearing capacity to support the heavy weight of soil, water, and vegetation needed for green roofs.
- *Underground utility clutter:* Beneath old streets lies an dense network of utility pipes (gas, water, electricity, fiber-optics), making the deep excavation required for installing porous pavement systems and water storage tanks highly challenging.
- **Socio-economic challenges:**
- *Fragmented property ownership:* Old residential buildings often have multiple individual owners and lack functional Owners' Corporations. Reaching the necessary consensus for implementing retrofitted green roofs is extremely difficult.
- *High retrofitting and maintenance costs:* Upfront installation and subsequent maintenance (irrigation, structural checks, replacing clogged porous materials) are expensive. Low-income residents in old districts cannot afford these additional costs.
- *High opportunity cost of land:* Land in Hong Kong is extremely scarce and valuable. Developers and public bodies prefer maximizing gross floor area over setting aside space for green infrastructure.

Part (a) (Max 4 marks):
- Award 1 mark for each valid contrast using data from the table (up to 4 marks).
- Greenery comparison: 41% vs 12% (1 mark)
- Albedo comparison: 0.35 vs 0.15 (1 mark)
- Runoff coefficient comparison: 0.30 vs 0.85 (1 mark)
- Air quality (\(PM_{2.5}\)) comparison: 22 vs 38 \(\mu g/m^3\) (1 mark)

Part (b) (Max 6 marks):
- **Greenery effect (Max 3 marks):**
- Explains transpiration mechanism (absorption of latent heat) (1 mark)
- Explains canopy shading (blocking direct solar radiation to concrete) (1 mark)
- Direct comparison/link to District Y's data (1 mark)
- **Albedo effect (Max 3 marks):**
- Defines high albedo as reflecting more shortwave solar radiation (1 mark)
- Explains less heat absorption leading to less re-radiation as longwave thermal energy at night (1 mark)
- Direct comparison/link to District Y's data (1 mark)

Part (c) (Max 8 marks):
- **Physical challenges (Max 4 marks):**
- High-density/narrow streets layout limiting ground space (1-2 marks)
- Structural safety/load capacity limitations of old buildings for green roofs (1-2 marks)
- Complex underground utilities hindering porous pavement construction (1-2 marks)
- **Socio-economic challenges (Max 4 marks):**
- Fragmented ownership (multi-owned properties) preventing consensus (1-2 marks)
- Financial constraints/high retrofitting and maintenance costs for poor residents (1-2 marks)
- High opportunity cost/economic priority of maximizing floor area (1-2 marks)

Part 1: Physical Causes of Mass Wasting in HK (Max 6 marks)
- Geological: Hong Kong is dominated by granitic and volcanic rocks, which are prone to deep chemical weathering under hot, humid conditions. This forms a thick, unstable layer of regolith and loose colluvium on steep slopes (slopes > 30 degrees). Intensive joints and fault lines further weaken the rock structure.
- Climatic: Hong Kong experiences a subtropical monsoon climate with intense summer rainfall and frequent typhoons. Heavy downpours trigger rapid infiltration, raising the water table and increasing pore water pressure inside the slope. This increases the weight of the slope (shear stress) while drastically reducing the friction and cohesion of the materials (shear strength), triggering landslides.

Part 2: Evaluation of Hard Engineering Measures (Max 6 marks)
- Hard engineering methods include shotcreting (concrete spraying), retaining walls, soil nails, and concrete drainage channels.
- Strengths: Highly effective and reliable for immediate risk reduction. Soil nails pin unstable soil layers directly to stable bedrock. Shotcreting and drainage channels prevent water from infiltrating the slope, which directly tackles the climatic trigger.
- Weaknesses: High construction and maintenance costs. They are aesthetically displeasing (visual pollution) and destroy local ecosystems/habitats. Concrete covers block natural vegetation growth, increasing ecological damage. Furthermore, they are prone to degradation over time and cannot be practically applied to all natural terrains across Hong Kong.
- Conclusion: While indispensable for protecting high-risk urban margins, they should ideally be integrated with soft engineering (e.g., bio-engineering, greening) to achieve ecological sustainability.

Explanation of physical factors (Max 6 marks):
- Geological (Max 3 marks): Identifies granitic/volcanic rocks prone to weathering (1); mentions steep relief/slopes >30 degrees (1); explains jointing/faulting reducing rock strength (1); mentions thick, loose unconsolidated regolith/colluvium (1).
- Climatic (Max 3 marks): Identifies subtropical monsoon climate with heavy, intense summer rainfall (1); explains how rainwater infiltration increases pore water pressure (1); explains the reduction of shear strength and/or increase in shear stress (weight) triggering slope failure (1).

Evaluation of hard engineering (Max 6 marks):
- Identifies common hard engineering techniques (e.g., shotcrete, retaining walls, soil nails) (1).
- Arguments for effectiveness (Max 2 marks): Immediate and highly reliable physical support (1); shotcrete/drains prevent water infiltration, addressing the main climatic trigger (1); essential for high-density areas (1).
- Arguments against effectiveness / limitations (Max 2 marks): High construction and long-term maintenance costs (1); high environmental impact, including loss of biodiversity and aesthetic/visual pollution (1); risk of sudden catastrophic failure if maintenance is neglected or drainage blocked (1); impractical for extensive natural terrains (1).
- Evaluative conclusion / overall judgment (1): E.g., Recognizes that hard engineering is necessary for high-density urban areas but should be coupled with soft engineering / greening for environmental sustainability.