Paper 3 - Physical fieldwork Flashcards
What is the title of the physical fieldwork?
How does the cross-section of the River Tarell change as we move downstream?
What theory do we test our physical fieldwork against?
Bradshaws model
What makes a fieldwork question suitable for a geographical enquiry?
if it is:
- small-scale
- easily repeatable – testable
- has a model to test/theory to test
- place is easy to reach
- if there are methods/data available
- got to be geographical
What makes our physical fieldwork question suitable for a geographical enquiry?
- 1 small river - look in a day
- small scale
- geographical
- easy to get to
- we can test it against Bradshaws model
Why was our physical fieldwork question a suitable title? (example answer)
This inquiry is suitable because it is clearly a geographical question because we are focusing on a river. It is also an appropriate scale because we are only finding the depth and width so we can easily collect the data in one day. Because it is close, we can easily get to the river and collect the data.
What does a good location for a fieldwork enquiry need to be like?
- low-risk – pretty shallow
- easy to measure
- easy to get there
- easily accessible
- practicalities – safety – access – scale
- links to geography
- availability, reliability and accuracy of data
- capacity collect sufficient information to draw reasoned conclusions
Explain two factors that you considered when picking the location of your fieldwork? (4 marks)
One reason I chose the river Tarell was because of practicalities. It was easy to get there so I could get there and back in one day. It was also easily accessible so I could easily collect data from the source to the mouth and compare it to Bradshaws theory. Another reason I picked the river Tarell is because the river isn’t too deep or dangerous so I can safely test it without getting hurt.
What did Bradshaw’s model say about rivers?
- It would get wider downstream
- It would get deeper downstream
- SO the cross section should get larger
What are the risks of the location we chose for the physical fieldwork?
- falling into river
- getting lost
- twisting ankle
- busy roads
- hypothermia
What actions could we take to reduce these risks from our location? (physical fieldwork)
- choose location carefully to get into river - so you don’t fall in
- mobile device/map - so you don’t get lost
- wear walking boots - so you don’t twist your ankle
- cross road as a group - so don’t get hit by a car
- wear appropriate clothing - to reduce hypothermia
What is primary data?
Data that you collect yourself
e.g. measuring width of a river
What is secondary data?
Data that has been collected by another organisation
e.g. the census
Why did we measure the width of the river?
- We wanted to see how the cross-section of the river Tarell change downstream, cross sections are made up of width x depth so we had to measure the width
- Bradshaw suggested that the width would increase as you go downstream so we had to measure this to see if that was true
What were good things about measuring the width of the river?
- It was quick and easy to measure
- We used portable and cheap equipment
What were bad things about measuring the width of the river?
- In the middle and lower course, the tape measure was tugged on by the fast river so the data is less accurate
- But we overcame this by adding more people to hold it in a straight line
What was the overall view about measuring the width of the river?
- Quick, easy and gave fairly accurate measurements
- So overall successful
- it followed Bradshaws model
Why did we measure the depth of the river?
- We wanted to see how the cross-section of the river Tarell changed downstream, cross sections are made up of width x depth, so we had to measure the depth
- Bradshaw suggested that the depth would increase so we had to measure this to see if that was true
What were good things about measuring the depth of the river?
- easy and quick
- portable and cheap equipment
- measured five times so created more accurate results
What were bad things about measuring the depth of the river?
- As we moved downstream the gaps between the measurements became further apart so was less accurate
- In faster currents, it was harder to keep the stick straight
What was the overall view about measuring the depth of the river?
- Quick, easy and gave fairly accurate results
- So overall successful
- it followed Bradshaws model
What is Stratified sampling?
taking a sample from each group (upper/middle/lower course)
Why did we use stratified sampling?
- We chose 10 sites spaced out along the long profile
- 3 in the upper, 4 in the middle, 3 in the lower
- We did this to see changes along along profile
- Some of the river was difficult to access (private) or too dangerous to get into (too deep/fast flowing) so we had to choose our sites to an extent
Why was using stratified sampling good?
- see how it changes + compare it to Bradshaw’s model
- can choose the sights so it’s accessible
Why was using stratified sampling bad?
choosing safer sites may be shallower so you influence results
What was the overall view of using stratified sampling?
What secondary data did you use?
Google earth
Why did you use secondary data (google earth)?
- to familiarise myself with the area of the fieldwork before going out on the field trip
- to choose suitable sites for data collection based on accessibility
- to add to my primary data
Why might you use maps in your enquiry?
- to see how easily accessible the location is so you can easily get there
- to familiarise myself with the area of the fieldwork before going out on the field trip, so I can choose suitable sites for data collection based on accessibility
- for putting data on it so I can see where the sites were
Why might you use photographs in your enquiry?
- gives a visual view of the river so you can show important features
- more accurate than a sketch so may be used to make measurements
What 2 methods did you use to present data?
- bar chart to present width
- located cross section
Why did you use a bar chart to present width?
What was good about using a bar chart to present width?
- easy to understand and analyse
- shows a trend clearly
What was bad about using a bar chart to present width?
- only has width - not depth
- doesn’t show where the upper/middle/lower course is of the sites
What was the overall view of using a bar chart to present width?
quick and easy to understand but doesn’t actually answer the question
Why did you use a located cross section?
What was good about using a located cross section?
- shows cross-section – both width and depth and the shape of cross-section
- very visual
- shows all of the data
What was bad about using a located cross section?
- harder to see trend
- can only see 3 sites - not all
What was the overall view of using a located cross section?
harder to understand but actually answers the question
What did we find out from our investigation?
- width does increase as you go downstream
- depth does increase as you go downstream
How do the graphs of our data help us answer our question? (6 marker?)
- Our question was: How does the cross-section of the river Tarell change as you move downstream?
- Bradshaw said that the width + depth would get bigger as you go downstream so the cross-section increases in size
- Our width showed that the river did get wider as you go downstream
- This allowed us to accept Bradshaw’s theory
- Our depth showed that it varies in depth but generally gets deeper
- This allowed us to generally accept Bradshaw’s theory
- Overall the results helped us answer a question and also to test Bradshaw’s theory
Do you trust the results we obtained for width? and why?
I trust them 90%
Why:
- We did the testing ourselves so not relying on potentially inaccurate results
- We did it multiple times
- We did all on the same day so we did it in one time frame
- Clear measurement equipment
- Easy to read
- Easy methods are results likely to be accurate
Why might the results we obtained for width not be completely trustworthy?
- Couldn’t fully reach sides – there was undercutting – narrow – slightly underestimated width
- Plants made it hard to find edge
- Lower course – current was faster – tape got caught – slightly overestimated width
Do you trust the results we obtained for depth? and why?
I trust them 80%
Why:
- We did the testing ourselves
- We did it multiple times (average)
- Easy to read/measure
- Easy methods so results are likely to be accurate
- Simple equipment
Why might the results we obtained for depth not be completely trustworthy?
- fast current made the ruler bend - slightly overestimated
- because we chose safer sites - may have influenced results - underestimate
Evaluate the reliability of your results (6 marks)
- Overall our width results were reliable because we did the testing ourselves so we weren’t relying on potentially inaccurate results. We also used simple measurement equipment so they are easy to read results from.
- sHowever, we couldn’t fully reach the sides of the river because of the undercutting and plants on either side of the river. This would make the results of the width seem narrower so we slightly underestimated the results.
- Overall our depth results were reasonably reliable because we did the testing in each section of the river multiple times to find an average so this made the results of the depth more accurate.
- However we chose safe sites for us to record results from so this may have influenced results, and underestimated the depth of the river.
- Therefore, overall, the results were fairly accurate, with a few factors that affected the width and depth, so we can still find out the cross-section of the river fairly accurately
To what extent were the results of this inquiry helpful in reaching a reliable conclusion (9 marks) - POINT 1 (sampling)
- POINT 1: the results we got were useful in helping us reach a reliable conclusion because they gave us accurate data from 10 sides
- GOOD: this allowed us to look at the river at different parts of its course so we could see if it matched Bradshaws theory
- BAD: however we only had 10 sets of data and the river Tarell is 10 km long, if we wanted to be sure that this relationship fitted Bradshaw’s model we would have to collect data from more sites. This would allow us to see how it varies over a greater amount of its length, giving us a fuller picture of how width and depth change downstream.
- OVERALL: despite this, because we collected data from each section of the river (upper, middle + lower) it allowed us to accept Bradshaws conclusions
To what extent were the results of this inquiry helpful in reaching a reliable conclusion (9 marks) - POINT 2 (methods)
- POINT 2: the methods we did gave us accurate data that allowed us to make a reliable conclusion
- GOOD: the method that we used were both easy to do. Because the channel depth was not even across the cross-section, we measured the depth five times across the channel to reduce the impact of anomalies and this allowed us to record accurate results which would help us reach a conclusion
- BAD: however, the data was less accurate downstream as the tape got caught in the current making the river appear slightly wider and as the river got wider there were larger gaps between depth measurements so our data may have been distorted by a number of large boulders
- OVERALL: Despite this, I am confident that the results gave me a reliable conclusion that the width and depth fitted Bradshaw’s model
To what extent were the results of this inquiry helpful in reaching a reliable conclusion (9 marks) - POINT 3 (presentation)
- POINT 3: the presentation methods showed us how the shape of the cross-section changed so we were able to come to a reliable conclusion
- GOOD: the located cross sections showed both the width and the depth so it allowed us to see the shape of the channel and what it looked like at each location, also because they were located on a map we could see how far apart the sites were and which part of the river they were in
- BAD: However it was more difficult to easily see trends as the graphs were not next to each other
- OVERALL: Despite this, it was a reliable way to show how the shape of the river channel change downstream but it is more difficult to see if the river match Bradshaws predictions
To what extent did the results and the conclusions meet the original aims (9 marks) - PART 1
- Our physical fieldwork aim was to investigate how the cross-section of the River Tarell changes as it goes downstream and to test Bradshaw’s theory
- We used stratified sampling to collect data along the entire length of the River at 10 locations. This allowed us to test Bradshaw’s theory as we collected results from the upper, middle and lower sections of the river.
- However, we had to choose our sites within the upper and middle and lower course because we wanted to make sure they were safe so we may have slightly understated how much the cross-section grew as we chose sites that were shallower
- Overall, the results gave us a spread of data along the long profile and and so we can accept the conclusions that the cross-section got bigger and therefore were able to meet the original aims of the inquiry and compare the results to Bradshaw
- …
To what extent did the results and the conclusions meet the original aims (9 marks) - PART 2
- The methods also allowed us to collect results that helped us meet our original aims. Cross-section is made up of width and depth, so by collecting this data we were able to work out how the cross-section changed. Additionally, because they were both simple methods that were easy to do, their results are more likely to be accurate
- However, our results for the width became less accurate as we went downstream because the current was stronger so pulled on the tape measure, so we may have slightly overstated how wide the river got. Also, the wider river downstream meant there were wider gaps between our depth measurements downstream so our depth became less accurate as we moved downstream because the measurements were further part so less representative of the cross-section
- Despite this I am mostly confident the results were accurate and therefore allowed us to meet the original aims of the inquiry
What were the problems with measuring the width of the river and what improvements did you make?
- Problem: as the river got wider, it became more difficult to get completely accurate measurements because the tape got caught in the faster water so stretched
- Improvements: to improve this we could’ve placed several people at points across the river to hold the tape
- Results: this would’ve likely made our results lower than record
- Conclusion: this may mean that the width did not increase as much as we concluded but the difference was only minimal. So our conclusions were still valid
What were the problems with measuring the depth of the river and what improvements did you make?
- Problem: as we moved downstream, and the river got wider, the gaps between the depth measurements also became wider, so the results did not represent the cross section as well here
- Improvements: to improve this we could’ve used systematic sampling and measured every 20cm
- Results: this would mean the depth results were equally representative at the upper course and middle and lower course so would be more reliable
- Conclusion: this would allow us to see more representative cross-sections so we could make more valid conclusions about how they had changed. However it is unlikely that this would change our conclusions significantly
What general improvements could we have made to the methods?
- Go back and redo it on a different day - so I could take an average and check for accuracy and also see the influence of different weathers
- Measure at more sites with smaller gaps between them - so I’d have a more accurate representation of how the river changes as we move downstream
Why did you measure the cross section under a bridge?
We measure the width and depth of the river under a bridge to see what impact humans (+ human interaction) might have on those features
What changes did you see with the measurements under the bridge?
- Our measurements showed that the river got narrower but deeper here
- These results were fairly accurate but the river was very fast flowing here and deep so it was difficult to hold the measuring stick still or to read the measurement accurately
- Also we should have taken readings under more than one bridge to see if this was always the case.
- Overall, however, we were fairly sure that the river got in narrower but deeper when humans built bridges over rivers
What is random sampling?
- the sites where data is going to be collected are selected at random
- e.g. closing eyes and pointing to places on a map
What are pros of random sampling?
- Can be used with a large sample or sample area
- Avoids any bias as it is totally random
- Easy to carry out the same fieldwork again
What are cons of random sampling?
- Data will not be evenly distributed
- There could be gaps in your data (or areas missed – particularly if the study area is large)
- Some of the sites may be difficult to access
What is systematic sampling?
- The sample is agreed upon using a specific rule when out in the field
- e.g. measuring every 2 m along the transect, or surveying every 10th shop
What are pros of systematic sampling?
- Data is evenly distributed across an area e.g. every 10th house
- More straightforward than other sampling types
- Ensures a good coverage of the area
What are cons of systematic sampling?
- The selected rule may not work out in the field
- May be biased in the results as different areas/ or pieces of data do not have equal chance of being selected
- May not be representative
What is stratified sampling?
- A sampling frame made up of sub-sets is used to choose the sites – it needs to be representative and proportional to the total area
- e.g. choosing 3 sites from each section of a coastline
What are pros of stratified sampling?
- This gets good coverage of the data or area so results are more representative
- Can be used with other sampling techniques
- Easy to compare sub-sets
What are cons of stratified sampling?
- Have to research the area before data collection in order to choose the sample – to check subsets
- Proportions of subsets need to be accurate
- Bias can be introduced into the sample
