What is my enquiry question?
How and why do beach characteristics change along a stretch of coastline?
What are my three hypotheses?
- beach width increases moving north from Torcross
- sediment size decreases moving north from Torcross
- coastal protection increases with land value
What is the location of my coastal fieldwork?
- Slapton Sands halfway down Start Bay
- in the county of Devon
- South Coast of the UK
What are the physical features of Slapton?
a shingle bar with a freshwater lake (Slapton Ley) behind it and the sea on the other side
What are the human features of Slapton?
- population of 434 in 2011
- Torcross is a town found at the end of the bar - protected by a sea wall of £330,000 in 1980
Why did we go to Slapton?
- large enough to see variations in processes and protection methods
- not too big so safe to navigate around
- lots of coastal processes and protection methods in Start Bay
What were the different methods of data collection?
- beach profiling (systematic every 500m)
- lithology (random)
- cost-benefit analysis (stratified)
- photos (stratified)
- field sketches (stratified)
Describe beach profiling in detail
- one person stands at the bottom of a facet and another stand on the top
- the distance between them is measured
- the person at the top of the facet holds a ranging pole while the person at the bottom measures the angle between them using a clinometer and looking at a point on the ranging pole
- repeat for the whole width of the beach, every 500m
STRENGTHS: allows us to collect numerical data and easy to complete
WEAKNESS: needs equipment and groups
Describe lithology in detail
- we randomly selected 10 rocks every 500m along the beach
2. we used a calliper to measure the width of the sediment along its longest side
Describe cost-benefit analysis
- completed a table for the coastal protection types used at Torcross and further up the coast where there were no settlements
Describe how we completed the field sketch and photography
drew a sketch of the view of the beach from Torcross and another further down the beach as well as photographs (making sure equipment were charged up)
How was accuracy of our data collection ensured?
- in groups to ensure everyone agreed on any measurements taken
- groups completed pilot studies (practise with the equipment)
- six areas used to collect beach profiling data to ensure representative results of the whole of Start Bay
What is the mean size of sediment at site 1 compared to site 5? (lithology)
Site 1 - 5.1cm (0km north)
Site 3 - 2.6cm (1km north)
Site 5 - 1.9cm (2km north)
(shows sediment size decreases moving north from Torcross)
What is the beach width at site 1 compared to site 6? (beach width)
Site 1 - 22.9m (0km north)
Site 3 - !!!! anomalous - 20.7m (1km north)
Site 4 - 27.6m (1.5km north)
Site 6 - 30m (2.5km north)
(shows beach width increases moving north from Torcross)
What secondary data did we use?
BGS (British Geological Survey) data to investigate physical processes in the bay - found chalk and limestone geology and shingle beach this enabled us to see if the primary data was in line with more large scale data collection - allowing us to question the validity of data
government data of costs of coastal defences e.g. Torcross sea wall £330,000 in 1980
What is the enquiry process?
- develop key question
- data collection (techniques/methods)
- process/present results
- results analysis
- conclusions
- evaluation
How did I represent my results?
sediment size = compound bar chart (with location on x axis) - allowed more than one data set to be plotted on the same graph as data from all 6 collection sites could be plotted - allowed comparison - however could be difficult to draw especially if the scale used is not appropriate
How were results analysed?
analysed by looking at the graphs drawn and the patterns in the data to conclude whether the hypotheses were correct
How was technology used to support my fieldwork?
- GE graph was used with google earth - enabled us to plot data onto the map of Start Bay - enabling us to see the spatial variations visibly between the different areas
How did I analyse my results and form conclusions?
- can be concluded that beach width does increase as I move north from Torcross (22.9 - 30m wide 0-2.5km north) - due to the process of longshore drift moving sediment north away from Torcross as we would expect
- can be concluded that sediment size does decrease as you move north from Torcross so second hypothesis accepted (5.1cm - 1.9cm wide 0-2km north) - expected due to attrition acting on the sediment as it moves north
What must I include in an evaluation of my enquiry in Slapton Sands?
- what went well
- what didn’t go well
- how to improve Next Time:)
What went well at Slapton?
- large volume of data collected - 6 sites along Start Bay
- variety of qualitative and quantitative data provided representative results
- backed up by secondary data
- bias minimised by using groups and varying sampling methods
What didn’t go well at Slapton?
- location only visited once on a week day in January therefore findings were not representative and conclusions may not be reliable
- some groups had more time than others to do pilot studies so some may have had more accurate results
How could I improve Slapton?
- visit more regularly at different points in the year to compare results e.g. visiting in July and different times of day as this could impact rates of erosion and processes occurring at the beach
- more pilot studies
- study different transects and areas of the coastline
