O-LevelGeographyThe natural environment2217/21 · May/June 2010 · Q730 Marks

A group of students was investigating the effects of groynes on a beach. Groynes are structures built out into the sea to stop or slow down longshore drift. A groyne is shown in Photograph B (Insert).

(a)State two safety precautions that the students should take when doing fieldwork on a beach. 1 2[2]
(b)(i)Complete Fig. 12, below, to show the movement of a pebble by longshore drift. [Figure 12][2]
(b)(ii)Write the following labels in the correct boxes on Fig. 12. Direction of longshore drift Direction of the prevailing wind[1]
(b)(iii)Explain the process of longshore drift.[3]
(c)(i)First, the students investigated the direction and rate of longshore drift. To do this, they painted 50 pebbles from the beach in bright red paint and left them in a group where the waves were coming up the beach. Suggest why the students painted the pebbles[1]
(c)(ii)Later, the students measured the distance each pebble had been moved along the beach, and they measured the long axis of each pebble, as shown on the sketch below. The results are summarised in Table 3 (Insert). Use the information from Table 3 to complete Fig. 13 below by filling in the missing bar and long axis measurement. [Table 3] [Figure 13][2]
(c)(iii)What did the students learn from this investigation about the impact of longshore drift on the movement of pebbles?[3]
(d)(i)Look again at Photograph B (Insert). The students took measurements every five metres along the groyne away from point X. At each five metre point they measured from the top of the groyne to the beach material on both the north and south side, as shown on Fig. 14 below. [Photograph B] [Figure 14] The measurements are shown on Table 4 below. [Table 4] Estimate the average measurement from the top of the groyne to the beach material on the south side of the groyne. Choose your estimate from the following and write your answer on Table 4. 1.2m 1.5m 1.9m[1]
(d)(ii)Use the data from Table 4 to complete Fig. 15 below. Draw in the bars for 5m and 10m on the south side of the groyne. [Table 4] [Figure 15][2]
(d)(iii)What conclusion could the students make about Hypothesis 1 Groynes reduce the movement of material along a beach? Use data from Table 4 and Fig. 15 to support your answer.[3]
(e)(i)Next, the students did an investigation to see how the groynes affect the beach profile (Hypothesis 2). Describe how they would measure a beach profile to get the results shown in Table 5 (Insert). You may draw a sketch to help you. The students used the following equipment: • Two ranging poles • A clinometer • A tape measure • A recording sheet [Table 5][4]
(e)(ii)The students plotted their results to create the beach profiles shown on Fig. 16 (Insert). Describe two differences between the beach profiles north and south of the groyne. [Figure 16][2]
(e)(iii)What conclusion could the students reach about Hypothesis 2 Groynes affect the beach profile?[1]
(f)Later, the students discussed their beach fieldwork and how they could have improved the accuracy and reliability of their results. What suggestions could they have made?[3]

This question uses a diagram from the original paper, which isn't shown here. Open the full paper from the past papers archive to see it.

Mark scheme

Marking points from the official mark scheme (May/June 2010). The mark or mark type is shown in brackets.

[2] Consult tide tables/work at low tide/watch out for waves and currents
Watch out for slippery rocks/uneven groyne
Avoid working near foot of crumbling cliffs/wear hard hat
Wear protective clothing/clothing that is easily visible
Wear shoes to protect against sharp objects
Use sunblock
Take a mobile in case of emergency/to call for assistance
Stay in group/pairs
NOT: work under teacher supervision/don't go into sea
[2] 1 mark for each arrow linking pebble positions, i.e. direction of swash
direction of backwash
1 mark max. if no arrow heads
[1] Left box: Direction of prevailing wind
Right box: Direction of longshore drift
Both correct for 1 mark
[3] Wind drives waves/wave move in direction of wind
Waves come to the beach at an angle/oblique
Swash carries material up the beach
Backwash takes material back down the beach
Process is repeated with each wave
No credit for swash/backwash by themselves
[1] Make them easy to see
See how far or in what direction the pebbles had moved
[2] 1 mark for plotting and shading bar graph: 8
Ignore shading
1 mark for accurate pebble size: 4cm (4 squares)
[3] Longshore drift moves pebbles along the beach (NOT down beach)
Most pebbles/specific number of pebbles moved between 20–40 metres
Accept any two groups between 10-50 m
Smaller pebbles moved further than larger pebbles
Mode is 20-30 m
[1] 1.5 (m)
[2] 1 mark for each bar
5 m = 1.2; 10 m = 1.5
1 mark max. if lines drawn on bars
[3] Hypothesis is correct/groynes do reduce movement of material – reserve
North side of groyne has bigger build up of material
Distance from top of groyne to beach material is less on north side
Groyne has less influence towards sea/more than 25–30 m away from point X
Credit comparative data for N & S of groyne to 1 mark max. (not reserve)
e.g. average measurement from top of groyne to beach = 1.1 to north, 1.5 to south of groyne.
No credit for explanation, e.g. trapping material
1+2
[4] Establish eye level height on each pole and mark it with a piece of visible tape/top of pole
Use tape measure to measure 10 m/distance between poles
Put the two ranging poles at 10 m intervals across beach
Hold the clinometer at arm's length and sight the visible marker
Read the angle of deviation from the horizontal/measure the angle with the clinometer
Record the angle on a recording sheet
Repeat every 10 m along/up/down/across beach
Take measurements on north and south sides of groyne
[2] Steeper profile on the north side of the groyne
More uneven profile on the north side of the groyne
North side of groyne is higher
Answer must be comparative
NOT more material on north side of groyne
[1] Hypothesis is true/groynes did/do affect the beach profile
Accept 'Yes' + hypothesis
NOT 'Yes' by itself
[3] Do more profile measurements either side of the groyne/every 5 m
Do more profile measurements at different sites along beach/at other groynes on this beach/at sites where there are no groynes on this beach
NOT on other beaches
Test if the results would be the same at different times of the year/days/conditions
Check accuracy of measurements for angle of profile/distance between ranging poles/from top of groyne to beach (What)
Check accuracy of measurements by doing more often and calculating average/more people involved/same people do all measurements (How)
1 'fallback' mark for check accuracy of measuring/check if measuring done correctly – if no other detail
NOT check pebbles data