What is qualitative data?
Results that can not be expressed as numerical values
e.g. field sketches, photographs
What is quantitative data?
Data that is expressed using numerical values
E.g. velocity, build up of sediment, gradient
What is random sampling?
In each location you take pebbles from random points rather than set intervals - makes method unbiased
What is stratified sampling?
Samples would be split in to groups
- e..g, three sites from each section of coastline
- can be mixed with systematic and random sampling
What is systematic sampling?
Carry out measurements at regular intervals e.g every 10m - gives good coverage of area
Advantages of stratified sampling?
- can be used with other sampling
- very flexible
- comparisons can be easily made
Disadvantages of stratified sampling?
- it can be hard to stratify data such as questionnaire responses as it may be hard to identify peoples ages or background
Advantages of random sampling
- avoids bias
- can be used with large sample sizes
Disadvantages of random sampling?
- can lead to poor representation of overall population
- practical constraints of time availability and access to certain areas
Advantages of systematic sampling?
- more straightforward than random sampling
- good coverage of area can be achieved
Disadvantages of systematic sampling?
- more biased as not all areas have an equal chance of being selected
- could lead to over and under representation
Beach morphology
- put the pole at the shoreline and measure 10m towards cliffs/ sea walk with measuring tape then be second pole in position
- use clinometer to measure angle by selecting one line on the pole and aiming the clinometer at the same line on the other pole
- squeeze the trigger and check angle
Longshore drift
- place ranging pole into sand close to the sea
- place orange in the sea and start stop watch
- time 5 minutes and place second raging pole at the location where the orange is
- measure the difference using a measuring tape and record distance
- repeat 3 time for average
Sediment characteristics
- select sampling method
- place a quadrant on the ground and select 10 pebbles using your sampling method
- measure width using callipers
- using powers roundness index record the roundness or angularity of the pebble
- complete this at each stages of beach profile
Build up of beach material
- start at sea wall and measure the depth of sand against the groyne - place meter stick in ground and measure distance from the sand to top of the groyne
- repeat on other side of groyne
- measure 5m ( or 10 if it’s a long groyne) along the groyne and repeat measurements on either side
- repeat this until you reach end of the groyne or until it’s no longer safe
Vegetation (sand dunes)
- start at tide line and place quadrant on the floor - measure 10m towards the dunes with measuring tape and place ranging pole there
- count the different types of vegetation found in your quadrant + write them on data collection sheet
- repeat method very 10m for as long as it is safe/ necessary to do so
Possible limitations of data collection methods
- tide times - may not be able to explore full extent of beach
- user error for equipment such as clinometer
- time - could effect choice of sampling method - coverage of beach may not be satisfactory
- wind speed + direction will affect longshore drift
- may not be safe to carry out fieldwork close to cliffs
Risks
- trips, slips and falls - ground can be uneven
- drowning
- becoming cut off by tide
- rockfalls from cliffs
- poor weather
- hot weather - dehydration/heatstroke
