Physical Fieldwork

Question 1

Where is the river tillingbourne

Answer 1

surrey, se england, between guildford and dorking

Question 2

What is bradshhaws model?

Answer 2

a model that shows how the characteristics of a river change from the upper too lower course

Question 3

What were our hypotheses?

Answer 3

the channel width will increase downstream
the channel depth will increase downstream
the velocity will increase downstream

Question 4

Why do we expect the channel width to increase as we go downstream?

Answer 4

• as we go downstream, the river undergoes lateral erosion
  bc:
  -more water (due to tributaries joining and rainfall and durfance runoff), the water thereby gains energy and erodes the banks.

Question 6

Why do we expect the channel depth to increase downstream?

Answer 6

the water has more energy, so both lateral and vertical erosion occur, enlarging the depth of the channel to accommodate the greater volume of
- abrasian! increased load…

Question 7

Why do we expect velocity to increase downstream?

Answer 7

as more water flows downstream, more energy is in the system as there is a higher discharge, so the river therefore has more momentum and therefore a faster flow
-riverbed is also typically smoother as there r softer rocks
-the channel shape becomes more efficient downstream (wider and deeper), reducing friction and boosting velocity

Question 8

what secondary data can we use?

Answer 8

– use geology maps which show rock type and permeability; help explain infiltration and run odd
-rainfall data

Question 9

Give the secondary data

Answer 9

• greensand (a type of sandstone), clay and chalk in upper course (from the Albury Parish Council’s description and maps on the geolgogy)
• 900mm of rainfall per year on average (from the journal Science of the Total Environment)

Question 10

How did we present each data?

Answer 10

1 - width and depth
drew a river cross-section
2 - velocity
bar chart of velocity at one location vs other location

Question 11

what were the two different sites?

Answer 11

abinger hammer and shere church

Question 12

How can the question be improved?

Answer 12

-test more factors like the load ( by picking random stones and weighing their mass and volume (using a eureka can) or see how more round it gets to see attrition)

Question 13

how do we improve data collection

Answer 13

• be more professional
  -use more sample sites or use two sites that are much wider apart.
• we could have used a flowmeter or velocity sensor

Question 14

how do we improve data presentation

Answer 14

• plot our sites on a map to visualise how far the sites are away
• plot velocity on a box plot(box–and-whisker chart), which illustrates a median to results and the highest and smallest

Question 15

how do we improve data analys

Answer 15

-excluding anomolous results
-explore reasons for thosee anomolous resultssults; perhaps vegetation on the riverbanks

Question 16

how do we improve our conclusion

Answer 16

• ## using secondary data to support the conclusion

Question 17

how could we improve evaluation?

Answer 17

• critically assess: validity, precision of results and our uncertainties
  -highlight risk of bias; We might have unintentionally found data that matched out hypothesis and ignored data that didnt. (e.g. ignoring secondary data that shere is actually harder rock than abinger hammer as shere is chalk which is harder than abinger hammer’s sandstone. this limmited us fromm finding reasons why this was so)

Question 18

what r the 6 steps for a geographical enquiry

Answer 18

• introduction and planning
  -methods and data collection
• data presentation
  -data analysis
  -conclusions
  -evaluation