physical fieldwork Flashcards
hypothesis / title
the groynes at Avon beach effectively manage long shore drift
location : where you went and why there
Avon beach is on an area of coastline that may be affected by coastal processes such as long shore drift. We suspect this as the prevailing wind hits the shore at an angle. We can access this area easily by mini bus from school and access to the beach is easy for data collection.
method
On Wednesday the 3rd of July 2019 I stood at the shoreline and measured the distance from the top of the groyne on both the east and the west sides of the groyne. I repeated this at 3 meter intervals along the groyne. I did this for each groyne (5 in total). This was a systematic sampling. I recorded my results in a table.
I measured the sand on either side of the groynes to show if the groynes were effective. It would clearly indicate if sediment from long shore drift was being trapped and this would tell me how useful the groynes are as a type of hard engineering.
analysis and conclusion
My bar chart shows that overall the groynes at Avon beach are effective, given that there is a mean distance of 58cm on the west side and a mean distance of 80cm on the east side. There was only one result that suggested the groynes ineffective, groyne 4. The graph hows that the groynes were mainly effective at the eastern side of the beach, all these three had the biggest height difference. The graph also shows me that the hard engineering is protecting the beach because overall the trend is positive. The most effective groyne was groyne 2. Groyne 4 and 5 were anomalies as there was no real difference in the height of each side. The pass through or the groyne has be so effective they had trapped so much sediment that it had reached the top of one of the groynes. The groynes could also be damaged and need repairing.
MEAN DISTANCE EAST = 80CM
MEAN DISTANCE WEST = 58CM
strengths of a bar chart
+ very visual. Easy to plot by hand.
+ Full range of data can be seen together with the patterns and groupings of the data.
+ good for comparing sets of data
+ appropriate for discreet data
weaknesses of a bar chart
- there are only a sanp shot in time. It is suspected to weather and geological conditions, the graph does not show this.
How could the bar chart be improved
GIS - proportional symbols could have been used to show changes in sediment size along the shore. These could be located on a digital map using digimaps.
Scatter graphs to analyse the relationship between the distance along the beach and the groyne height.
Strengths of data collection
+ the method of data collection is simple to carry out.
+ systematic sampling is simple and had good coverage of the study area….
+ little equipment needed
+ equipment used to ensure accuracy
weaknesses of data collection
- a larger area would have given more accurate data
- there may be some user error when taking readings
- also tape measures need to be held straight and prevented form sinking into the sediment
what to do next time when collecting data
Measure more intervals on each groyne eg every 2 r 1 meter
Double check each measurement for accuracy
Compare different ties of the year
