Topic 6: Fieldwork (PHYSICAL)

Question 1

What was the enquiry question?

Answer 1

How effective are the coastal management strategies in Swanage Bay?

Question 2

Name the location you visited?

Answer 2

Swanage, Dorset, South Coast of England

Question 3

Explain why the location was suitable for the enquiry question?

Answer 3

This area has a range of coastal management strategies to study, it is a manageable size, it is accessible and safe.

Question 4

Write out your method to measure beach gradient (Quantitative – beach gradient)

Answer 4

1. Stick two ranging posts in the ground 2 metres away from each other.
2. Line up the clinometer with the ranging posts.
3. Measure the angle incline or decline up the beach.
4. Repeat every 2 metres.

Question 5

Write out your method to measure sediment characteristics (Quantitative)

Answer 5

1. Set out a grid on the beach 10metres x 10metres.
2. Use a random number generator to get 2 numbers e.g. 2 and 4. Go along 2 metres and up 4 metres on the grid and pick up a piece of sediment.
3. Measure the longest axis of the pebble using callipers in centimetres.
4. Repeat this 10 times and get an average sediment size. We also measured the roundness of the 10 pebbles by judging how round they were on Power’s Scale where 1 = very angular and 6 = very round

Question 6

Write out your method used to measure how people viewed the impact and success of coastal management (Qualitative - Questionnaire)

Answer 6

We asked 7 closed questions using a bi-polar scale. One of the questions was ‘Are you concerned about coastal erosion here?’ and the options were very, slightly or no.

Question 7

Write out your method used to measure the beach drop (Quantative - Groyne Profiles)

Answer 7

Using a tape measure, measure the height of an upright on the groyne from the sediment to the top of the upright.
Repeat this for each upright.
Repeat this on the other side of the groyne.
Calculate the mean height drop for both sides.
Use a tape measure to measure the beach width from the sea wall to the sea.

Question 8

Explain two sources of error in each of your methods

Answer 8

Beach gradient - Error when reading the clinometer, not holding the ranging pole straight.
Sediment characteristics - Natural tendency to pick up larger sediment despite sampling, Estimating the shape of sediment using the Powers Index was difficult to be accurate.
Questionnaire - We only really asked elderly ‘friendly’ people in reality despite random sampling, tourists might have outnumbered the locals.
Groyne profile - Human errors, tide changes affects the width of the beach

Question 9

How did you use sampling in each of your methods?

Answer 9

Beach gradient and Sediment characteristics - Systematic sampling: one location in the ‘retreat the line’ management area and another in the ‘hold the line’ management area.
Questionnaire - Random sampling: asking 10 random people along the sea front at Swanage Beach.
Groyne profile - Stratified to select groyne, systematically measuring height at each upright.

Question 10

What were the positives and negatives of your sampling strategies?

Answer 10

Beach gradient and Sediment characteristics - Covered both managed and unmanaged areas. We only measured once in retreat and once in managed.
Questionnaire - Random allows us to get a range of views from different ages. Might only ask ‘friendly’ people who tend to be elderly despite it being random.
Groyne profile - If compiled with others then we would have all 10 groynes. If not compiled, then there isn’t much of a range and enough evidence.

Question 11

Explain how the Geology map and Sediment Cell Transfer map (secondary source) of your location supported your investigation.

Answer 11

It shows that Swanage is a discordant coast. Swanage is found in a (clay) soft rock bay with high rates of erosion and is surrounded by Durlston and Ballard Headland which are hard rock (limestone/chalk).

It shows that sediment is transported along Swanage Bay from south to north.

Question 12

Write out your conclusion for beach gradient.

Answer 12

• The ‘hold the line’ management of Swanage Bay through groynes and beach nourishment has created a steeper and deeper beach than the ‘retreat the line’ section.
• The managed beach was 22 metres deep and rose to 2.2m high.
• The unmanaged beach was only 19 metres deep and 0.5m high.

Question 13

Write out your conclusion for sediment characteristics.

Answer 13

• The ‘hold the line’ management at Swanage has meant the sediment is larger than in the unmanaged ‘retreat the line’ section.
• The sediment in the managed area was larger and more angular with Powers 3. This is because it is trapped behind groynes and is being added through nourishment.
• The sediment in the unmanaged area was smaller and less angular with Powers 4. This is because the cliff in is collapsing and adding small sand particles onto the beach.

Question 14

Write out your conclusion for the questionnaire?

Answer 14

• Erosion is something people were worried about, with 65% saying very to 11% saying no.
• 75% of respondents said that the management had positively benefited business, shops and homes in Swanage, and 77% said that it had been positive for tourism.
• This is despite 67% of people saying the hard management is unattractive to the town of Swanage.

Question 15

Write out your conclusion for your groyne profiles?

Answer 15

The south sides of the groynes collected much more sediment as a result of the sediment travelling from south to north along the coastline.
At groyne number 4 the north and south sides were 19m wide.
On the north side the mean height was 108cm, and on the south side the mean height was 80cm.

Question 16

Explain how problems in your investigation (methods) might have affected the accuracy and reliability of your conclusions

Answer 16

Beach gradient - Error reading the clinometer, not holding the ranging pole straight. Instead use a digital clinometer on phone and use a spirit level.
Sediment characteristics - Only measuring the longest axis of sediment, natural tendency to pick up larger sediment. Instead measure all three axis and pick up three pieces from this point and take average.
Questionnaire - Only really asked elderly ‘friendly’ people in reality, only doing it at one time of day. Instead identify age groups and ask 3 young, 3 middle age, and 3 elderly and repeat it on other days/times.
Groyne profile - Human errors measuring the drops, use a digital measurer. Tide changes, measure at different times of day.