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GCSE · Physical Geography

GEO.PH19 Hot Desert Characteristics, Adaptations and Opportunities for Development

AQA 8035 · Calculators not allowed · about 50 minutes

Total Marks

Name: _______________________________ Date: ____ / ____ / ______

Answer ALL questions. Show all your working.

Define a 'hot desert' environment, naming the typical climate and vegetation context for deserts such as the Sahara or the Thar Desert.

(Total for Question 1 is 1 mark)

State a typical annual rainfall range (in millimetres) for hot deserts such as the Sahara or the Thar Desert.

(Total for Question 2 is 1 mark)

Describe the typical daily temperature range in a hot desert environment such as the Sahara or Thar Desert and explain why daily extremes occur.

(Total for Question 3 is 2 marks)

Give TWO physical features of hot desert soils, for example in areas of the Thar Desert or the Sahara.

(Total for Question 4 is 2 marks)

Figure 1: A simplified labelled diagram of a barrel cactus from a hot desert such as parts of the Sonoran or Sahara edge is shown here in words: Label A = thick fleshy stem, Label B = spines, Label C = shallow wide roots. Using the diagram context, explain the function of each labelled feature for survival in a hot desert environment.

(Total for Question 5 is 3 marks)

Figure 2: A simple labelled diagram of a dromedary camel features: Label A = hump, Label B = long eyelashes and closable nostrils, Label C = wide, padded feet. Explain how each labelled feature helps the camel survive in hot desert conditions like the Thar Desert.

(Total for Question 6 is 3 marks)

Give ONE behavioural adaptation of a desert animal, for example in the Sahara or Thar Desert, and explain how this adaptation reduces exposure to extreme heat.

(Total for Question 7 is 2 marks)

A small research station in a dry part of the Thar Desert recorded annual rainfall in two adjacent years: Year 1 = 220 mm, Year 2 = 55 mm. Calculate the percentage decrease in annual rainfall from Year 1 to Year 2, to one decimal place.

(Total for Question 8 is 2 marks)

Table 1: Vegetation cover measured at four distances from an oasis edge in a hot desert area (percentage ground cover).
Distance from oasis edge (m): 0, 50, 200, 1000
Vegetation cover (%): 65, 40, 10, 1
Using the table, describe the pattern shown by vegetation cover with distance from the oasis edge.

(Total for Question 9 is 3 marks)

Figure 3: Development opportunities in a hot desert region are listed here as stimulus for this question: large areas of flat, sunlit land suitable for solar farms; visible surface mineral deposits and small open-pit mines; an established tourist route with dunes and cultural sites; an irrigated belt of farmland near a permanent river or aquifer. Describe the opportunities for development shown in Figure 3, using the list above.

(Total for Question 10 is 4 marks)

Explain TWO benefits of developing large-scale solar farms in a hot desert region such as parts of the Sahara or Thar Desert.

(Total for Question 11 is 4 marks)

Give TWO challenges that developers face when trying to develop infrastructure or agriculture in a hot desert such as the Thar Desert.

(Total for Question 12 is 2 marks)

Explain the challenges of developing a hot desert environment such as the Thar Desert. In your answer, develop a clear explanation with supporting detail.

Explain the challenges of developing a hot desert environment such as the Thar Desert.

(Total for Question 13 is 6 marks)

You plan a simple fieldwork transect to measure soil moisture across a 500 metre transect from an oasis edge into the surrounding desert in the Thar Desert. Suggest a suitable method, including how you would sample and what equipment you would use.

(Total for Question 14 is 3 marks)

Explain ONE way that tourism can both help and challenge development in a hot desert area such as parts of the Sahara or the Thar Desert.

(Total for Question 15 is 3 marks)

Mark scheme · GEO.PH19 Hot Desert Characteristics, Adaptations and Opportunities for Development

Question 1

B1 a region with very low and unreliable rainfall and sparse, specialised vegetation (xerophytes), often very hot by day, oe
Answer: A region with very low and unreliable rainfall and sparse specialised vegetation, often with very hot daytime temperatures.

Question 2

B1 about 0 to 250 mm per year, oe
Answer: About 0 to 250 mm per year.

Question 3

B1 daytime temperatures can be very high (often above 40 degrees C) and nights very low (often near or below 0 degrees C), oe
B1 linked explanation, e.g. the low humidity and lack of cloud allow strong daytime heating and rapid cooling at night, oe
Answer: Daytime temperatures are often very high, above 40 degrees C, while nights can be near or below 0 degrees C. The low humidity and lack of cloud mean strong daytime heating and rapid night cooling.

Question 4

B1 sandy or rocky soil texture, oe
B1 low organic matter and low fertility, oe
Answer: Sandy or rocky texture; low organic matter and low fertility.

Question 5

B1 A: thick fleshy stem stores water for long dry periods, oe
B1 B: spines reduce water loss by shading the stem and deter herbivores, oe
B1 C: shallow, wide roots quickly absorb surface rainfall before it evaporates, oe
Answer: A stores water in a fleshy stem; B spines shade the stem and deter animals, reducing water loss; C shallow, wide roots absorb surface rainfall quickly before it evaporates.

Question 6

B1 A: hump stores fat that can be metabolised for energy and water, oe
B1 B: long eyelashes and closable nostrils protect eyes and reduce sand entering the nose, allowing survival during sandstorms, oe
B1 C: wide, padded feet prevent sinking into sand and aid walking on soft desert surfaces, oe
Answer: A hump stores fat that can be used for energy and water; B eyelashes and closable nostrils protect against sand and reduce water loss; C wide, padded feet stop the camel sinking and help walking on sand.

Question 7

B1 behavioural adaptation named, e.g. being nocturnal, oe
B1 linked explanation, e.g. active at night to avoid daytime heat, reducing water loss and overheating, oe
Answer: Nocturnal behaviour, active at night to avoid high daytime temperatures, which reduces overheating and water loss.

Question 8

M1 (220 - 55) / 220 x 100 or 165 / 220 x 100 seen, oe
A1 75.0% cao
Answer: 75.0%.

Question 9

B1 vegetation cover decreases as distance from the oasis increases, oe
B1 supported with data, e.g. 65% at 0 m, 40% at 50 m, 10% at 200 m and 1% at 1000 m, oe
B1 this suggests plants are concentrated near the water source and thin out rapidly with distance, oe
Answer: Vegetation cover falls rapidly with distance from the oasis: 65% at 0 m, 40% at 50 m, 10% at 200 m and 1% at 1000 m, showing plants concentrate close to the water and thin out quickly further away.

Question 10

B1 solar energy potential from large, flat, sunlit areas, oe
B1 mineral extraction from visible surface deposits and small mines, oe
B1 tourism based on dunes and cultural sites, generating income and jobs, oe
B1 commercial farming where irrigation is possible near a river or aquifer, oe
Answer: Opportunities include solar energy on large flat sunlit land; mineral extraction from surface deposits and small mines; tourism based on dunes and cultural sites providing jobs and income; and commercial irrigated farming where water sources exist.

Question 11

B1 benefit 1 named, e.g. renewable electricity generation using abundant sunlight, oe
B1 linked detail, e.g. generates low-carbon energy that can reduce fossil fuel use and be exported or used locally, oe
B1 benefit 2 named, e.g. job creation and new infrastructure, oe
B1 linked detail, e.g. construction and maintenance create local employment and can lead to improved roads and power grids, oe
Answer: Solar farms provide renewable electricity from abundant sunlight, cutting reliance on fossil fuels and allowing local use or export; they also create jobs during construction and maintenance and can bring infrastructure improvements such as roads and grid connections.

Question 12

B1 extreme heat causing problems for workers, machinery and materials, oe
B1 water scarcity making irrigation and human settlements difficult, oe
Answer: Extreme heat that affects workers and machinery; and water scarcity that limits irrigation and supply for settlements.

Question 13

Level 3 (5-6): Detailed explanation of multiple challenges with clear, linked detail and examples, showing how each challenge constrains development, and a coherent overall account.
Level 2 (3-4): Clear explanation of at least two challenges with some linked detail or an example, showing how they affect development.
Level 1 (1-2): One or two simple statements about challenges with limited explanation or detail.
Indicative content:
- Extreme heat increases costs and risk for construction, reduces worker productivity, and can damage materials and equipment, making building and maintaining infrastructure harder.
- Water scarcity limits irrigation for agriculture and increases the cost of supplying drinking water, requiring expensive pipelines, wells or desalination which raise development costs.
- Inaccessibility and vast distances raise transport costs for materials and finished goods, making commercial farming or industry less profitable.
- Temperature extremes and sand movement (dunes, sandstorms) damage roads, solar panels and buildings and increase maintenance costs.
- Environmental limits, such as fragile soils and limited native vegetation, make landscapes more vulnerable to disturbance and increase restoration costs.
- Examples could include the need to drill deep wells or import water, the expense of constructing roads over shifting sands, or providing cooling and maintenance for solar infrastructure.

Question 14

M1 method named, e.g. measure soil moisture at regular intervals (e.g. every 50 m) along the 500 m transect, oe
A1 equipment named, e.g. use a soil moisture meter or gravimetric sampling with labelled bags and a trowel, oe
B1 sampling justification or quality control, e.g. systematic sampling at set intervals and repeat measurements at each point to improve reliability, oe
Answer: Measure soil moisture at regular intervals (for example every 50 m) along the 500 m transect, using a soil moisture meter or by collecting samples with a trowel for gravimetric drying; take repeat readings at each point to improve reliability.

Question 15

B1 help point, e.g. tourism creates income and jobs in hotels, guiding and transport, oe
B1 linked challenge, e.g. tourism can be seasonal and put pressure on scarce water supplies and local infrastructure, oe
B1 linked development effect or balance, e.g. income may benefit some but increase inequality or cause environmental damage, oe
Answer: Tourism creates income and jobs in hotels, guiding and transport, helping the local economy; however it is often seasonal and can put pressure on scarce water and infrastructure, and may cause environmental damage or unequal benefits.

Hot Desert Characteristics, Adaptations and Opportunities for Development - Worksheets, Questions and Revision