AQA AS Geography
Unit 2 – Geographical Fieldwork
Temburong River: 5th February 2013
Name
Once a title (aim) has been decided, you must break the title down into an hypotheses (for Physical
investigations). These hypotheses will help you find an overall answer to the title.
Fieldwork Aim
To investigate the changing characteristics of the Temburong River with
increased distance downstream.
Fieldwork Hypothesis
Velocity will increase with distance downstream
Geographical Understanding of Hypothesis
What Geographical Understanding are you basing your
hypothesis on?
Bradshaw’s Model
According to Bradshaw’s model average velocity
will increase with distance downstream.
This is because more energy is needed to
overcome friction in the upper reaches of a river,
leaving less energy available for movement.
 Greater turbulence as the water moves over
the uneven bed means more internal
friction in the upper course.
 There is also greater external friction
under normal flow conditions, as large
boulders on the river bed increase the
wetted perimeter meaning that more
water is in contact with the bed & banks
giving the river a high hydraulic radius
(less efficient channel profile).
In the lower sections of the river,
 Flow is smoother meaning less internal
friction.
 Channel shape is also more efficient (lower
hydraulic radius) as cross-sectional area
is higher.
Since the river loses less energy to overcome
friction in the lower course there will be more
energy available for movement and thus flow
will be more rapid.
Location of Study Area:
Temburong River, Temburong District, Brunei Darussalam (Borneo)
The investigation took place along a 28km stretch of the Temburong River between its
confluence with the Belalong River in the Ulu Temburong National Park and the town
of Bangar
The first site was just into the upper course of the river whilst the final site was at the
beginning of the lower course.
Poor accessibility meant that only sites between these two points could easily be
reached.
Why is this a suitable river to investigate changing channel
characteristics downstream? What evidence is there from
the map?
The Temburong River has had little interference by people and for most of its course is
flowing through a natural channel.
The river between the National park and Batang Duri can be reached by longboat,
from Batang Duri to Bangar there is a road running alongside the river. Beyond
Bangar are mangrove swamps which are less accessible.
We also had local knowledge of the area.
Assess the extent to which this map is ‘fit for purpose.’
The OS Maps used were very out of date (1981).As Brunei has been in a state of
emergency (since a rebellion in 1962), OS maps are restricted and not available to
the general public.
The map is useful for measuring distance along the river, seeing relief to help
ascertain the stage each section of the river and helping to select sample points as
the proximity of the road to the river can also be seen.
However as the map was out of date some information was not accurate. The site of
some settlements had changed and not all tracks down to the rivers edge were
shown. Also in a couple of places there was some development alongside the river
which restricted access.
It was less easy to use the map further upriver, once we were in the boats as there
were fewer points of reference, so we used time intervals to help us judge where to
stop.
Risk assessment
You need to be able to carry out a risk assessment for any research you undertake –
outline the risks of carrying out research and suggest strategies for minimising risk.
Temburong - River
Hazard/Risk
Initial level
of risk
(L/M/H)
Control measures (strategy for reducing level
of risk)
Residual level
of risk
(L/M/H)
Boat Accident
M
Use reputable company with good quality
boats and experienced drivers.
Students told to listen to the boat driver’s
instructions, distribute their weight
evenly and not rock the boats
l
Drowning
M
Students to wear life jackets at all times
Be aware who the non swimmers are and
not let them go into water above their
knees.
Be aware of rainfall conditions upriver
and keep a constant eye on changing
river levels to avoid being caught in a
flash flood.
Keep a teacher lookout downstream to
prevent students going beyond a specified
point.
L
Fingers crushed
when boats
come alongside
each other
H
Warn students to keep their hands inside
the boats at all times, before leaving and
throughout trip.
L
Slipping on wet
stones
H
Wear shoes with good grips. Be aware of
conditions
L
Crocodile
attack
L
Do not enter rivers or go to close to the
waters edge in areas where crocodiles
have been sited
L
Sunburn
H
Use suncream & wear a hat
Work/rest under shade as much as
possible
L
Dehydration
H
Remind students to drink regularly
Provide extra supplies of water for whole
group
L
Insect bites
H
Use insect repellent
Wear long sleeved shirts / long trousers
L
Have first Aid kit & trained first aider in
group.
Have one teacher per 10 students
2) Data Collection - Methods
There are two types of data:
a) Quantitative data – information can be expressed in numerical terms. Research involves
using statistics to analyse data (e.g. river width).
b) Qualitative data – difficult to measure, count or express in numerical terms (e.g. nature of
relationships among groups in society, impacts of tourism in a named area).
Researchers also often talk about data being subjective or objective.
 Subjective – influenced by personal opinion.
 Objective – undistorted by personal bias.
You should also know the difference between primary and secondary data:
a) Primary data:
Data that is collected and processed by individuals (e.g. questionnaires, raw census data,
maps with annotations).
b) Secondary data:
Data that is collected and processed by other people other than the researcher in question
(e.g. processed census data).
Once you have decided what type of data you need to collect, you need to decide on a sampling
strategy to use to ensure that your results are as accurate and reliable as possible.
Why do we need to take a sample when carrying out research?
Cannot measure all points (no time)
If sampling is carried out carefully it can be representative of reality, whilst being
done in the limited amount of time available.
Sampling:
Samples are ideally collected to be representative, but in practice they are often selected as a matter
of convenience.
a) Random sampling:
Every value, or member of the “population,” has an equal chance of being selected and the selection
of one member does not affect the probability of selection of another member. Random sample is
obtained using random numbers, usually generated on a computer.
Advantage
There is no bias in this sampling method.
Disadvantage
This is a time-consuming method and be beware
that a random sample may miss an entire part of
the survey area.
b) Systematic sampling:
Values are selected in a regular way (systematically).
E.g. Choosing every tenth person on a list or every 20th house in a street.
Advantage
This gives an even coverage of the area being
investigated.
Disadvantage
There is some bias in this sampling method (all
points do not have an equal chance of selection).
c) Stratified sampling:
This is based on knowing something in advance about the population or area in question. If it is
known that there are important groups in a population, it is possible to make sure that a
representative sample of them is included in a survey.
E.g. If you are surveying the attitudes of local people to the opening of a supermarket, your sample
must reflect the age distribution of local people.
Advantage
Sample is representative
Disadvantage
Comment on how you have chosen to sample your data
Initially : Systematic
We had a 28km stretch of river which we have divided into 14 sites (one ever 2km)
Fine tuning: the position of these sites then had to be adjusted taking local
conditions into account; Accessibility to river (road/track nearby)
 Safety
 Feasibility (no dense vegetation on the bank)
Outline and justify one method of data collection








A piece of garlic was thrown into the fastest flowing part of the river
(Thalweg) at each site. And the time that it took to float 10m was recorded.
This process was repeated 3 times and then an average taken.
These results were converted from seconds per 10metres to metres per second
Garlic was used as it is
o Able to float
o Easy to see in the water
o Biodegradable
o Cheap
The garlic was thrown slightly upriver of the start point to enable it to reach
terminal velocity before the stopwatch was started.
A student stood by the start and signalled (with arm and a call) when the
garlic passed by.
The timer with the stopwatch stood by the finishing point so they could see
when the garlic had reached 10m.
Efforts were made to ensure the measuring tape ran parallel to the rivers
current to ensure the distance was accurate
SEE LABELLED SKETCH
Discuss the strengths and weaknesses of the method of
data collection
Strengths



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Easy
Doesn’t need much equipment :tape, stopwatch, garlic
Safe: Can do data collection from river bank (no need to get wet)
Feasible: Can carry out measurements in places where water is very deep
Weaknesses
 Only surface velocity can be recorded, so not representative of whole channel
velocity which will vary with distance from the bed and banks due to
changes in external friction)
 May not be able to position the garlic in the Thalweg
o Unsure of the exact location of the Thalweg
o Inaccurate throw
o Too far to throw
 As the garlic cloves were not all exactly the same size and mass this might
influence their velocity
 Difficulties in keeping the tape parallel to the current can lead to
inaccurate measurement (the garlic might travel further than 10m)
3 & 4. Data Presentation & Analysis
You must present data using appropriate methods – data must be presented visually and must show
all information clearly – it must be easy for the reader to pick out trends, patterns, anomalies in the
data.
Where appropriate, titles, scales and keys should be clearly marked on presentation.
Scatter Graphs & Spearman’s rank correlation coefficient
Correlation is a method whereby a co-efficient is calculated to describe the degree of association
between two sets of paired data/values. This co-efficient is then tested to determine the probability
that the association might be due to chance.
A correlation is concerned with assessing links, association or relationships between two or more
phenomena. It looks at the strength of the relationship between two variables or two sets of data.
Give examples of variables that you could correlate together:
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


Velocity & distance downstream
Velocity & depth of water
Velocity & hydraulic radius
Depth of water & distance downstream
Hydraulic radius & distance downstream
Bed load size and distance downstream
Bed Load size and velocity
Degree’s of correlation
Which variable to draw on which axis of the scatter graph?
Plot the INDEPENDENT variable on the horizontal axis
(termed the X axis) and the DEPENDENT variable on
the vertical axis (Y axis).
One variable usually has an effect on the other and this should enable you to identify the
independent and dependent variables.
Example:- temperature decreases as you go up the mountain. Height above sea level is the
independent variable but the variable that changes is temperature so that is the dependent variable.
Is a visual link precise enough?
Not really because it is far too subjective. Vague statements like “The scattergraph seems to me to
indicate a weak positive correlation…” are too imprecise. Applying the Spearman Rank Statistical Test
means you can QUANTIFY the strength of the relationship that your scattergraph reveals. It is more
objective and therefore acceptable to science.
Sketch of your Scatter Graph
Spearman’s Rank correlation coefficient
Null Hypothesis: There is no correlation between velocity and distance
downstream
Alternative Hypothesis: there is a correlation between velocity and distance
downstream
SEE TABLE OF RANKINGS
Rs = 1 - 6 x ∑d²
n³ - n
Rs = 1 -
6 x 788
14³ - 14
Rs = 1 -
4728
2730
Rs = 1 - 1.732
Rs = -0.732
As the calculated correlation coefficient (Rs) of -0.732 is higher than the
tabulated critical value of 0.646 at the 99% confidence level, we can reject
the null hypothesis and accept the alternative hypothesis.
Our data shows a significant negative correlation between river velocity
and distance downstream
Describe one technique you used to present data in this
enquiry and outline the advantages and disadvantages of it
A scattergraph was used as it clearly shows the nature of the relationship
between the two variables (velocity & distance downstream)
The main trend can be seen and anomalies identified.
However, interpretation is subjective and a correlation test needs to be used
to objectively assess the strength of the relationship between the two
variables.
If the correlation test fails, the scattergraph can provide evidence to explain
why this has happened.
The scattergraph only shows two variables, which need to be paired.
It doesn’t provide additional data which might be influencing the results ,
such a: Location of pools & riffles
 If sites were on a Straight section of river or at a meander
 Effect of people (bridge disturbing flow)
An alternative data presentation technique would be to superimpose the
results (in the form of bars) over a map or Google Earth image.
Outline and justify the use of one or more techniques used
to statistically analyse your results
A Spearman’s Rank correlation test was used.
This was relatively quick to carry out and provided an objective
assessment of our results. Major anomalies can affect the result, but
The test is easy to repeat, leaving out these anomalies.
But:
The Spearman Rank correlation test only test ranks and is therefore
not as accurate as the more complex Pearson’s Product Mode
correlation test.
We only had 14 pairs of data and would have got a clearer result if
we had managed to get more samples.
We also had problems deciding how to rank the negative velocities
where the river was flowing backwards (due to the influence of tides)
In this worked example a higher speed was given a lower rank if the
water moved backwards.
An alternative method is shown at the end of this report
5) Drawing conclusions and evaluation

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



Summarise the results to answer the original question/hypothesis
Support the summary with reference to evidence from earlier sections
Explain results in the light of theories/concepts and location
Identify limitations of methods and impacts on results - suggest improvements/extension
Explain possible effect of limitations on results
Examiner should be able to read conclusion and know what your study was about and what
you found out
Geographical Information Systems
What is this? – the most powerful set of tools in existence for the analysis and visualisation of spatial
information.
How might you go about using GIS in your investigation?
A smart phone could be used to take pictures of each site, with ‘location (GPS)
on’. These pictures could then be uploaded to Google Earth to pinpoint the
exact location of each sample point.
The actual distance between each site could then be measured and used on the
scattergraph, rather than just giving the rank of the distance downstream.
Bar charts can be superimposed onto the Google Earth Image (or Google Map)
to indicate velocity at each point.
Google Earth also shows features which might be affecting the results, such as
channel shape or human influences, such as bridges.
Summarise your findings and comment on how well they
support your background theory
We were expecting a positive correlation between velocity and distance
downstream, but our results showed a significant negative correlation which
opposed Bradshaw’s theory, as velocity actually decreased downriver.
The main reason for this was because although Bangar is more than 10km
inland the Temburong River is still tidal here. Hence at the time of our
investigation our three lowest sites were affected by a high tide, with the water
actually running backwards at site 13 & 14 and being stationary at site 12.
Without the final 3 sites the trend was still negative, but the correlation was no
longer significant. To get a positive trend the final 7 sites (half the data would
have to be omitted.
Another factor to take into account is that the majority of our sites were in the
middle course. Poor access further downstream into the lower course mangrove
swamps or higher into the upper course where it was too shallow for boats and the
valley sites were covered with impenetrable jungle, meant that we didn’t get the
full range of sites from source to mouth expected by the Bradshaw model.
Comment on the validity of your conclusion based on the
accuracy and reliability of the data you collected.
Accuracy:
 The garlic cloves were not the same shape or mass and this might have
affected their speed. Oranges could be used instead but this would be
expensive as 42 (14 x3) were needed
 The measuring tape might not have been parallel to the flow of the
river might so the garlic may have travelled more than 10m
 The movement of the garlic was disturbed at some sites by passing
boats.
Reliability:
 Results would be different at different times due to
o Changes in the tide
o Changes in discharge (due to rainfall difference)
Make recommendations for further research.
o
o
o
Return at different times (such as low tide or after heavy rain)
Try to get further into the lower course/upper course, but this will need
more time.
Use stratified sampling techniques which take location of pools/riffles or
straight sections/meanders into account when selecting sample sites.
In what ways would your conclusions be of use to other
people?
It would help people who use the river to know more about the
characteristics of its flow. This would include
 Passenger boats between Bangar and the capital city (Bandar Seri
Begawan)
 Grave barges
 Tourist boats to the national park
 Canoeists and people who go tubing from the Outward Bound Centre
Where water lows more slowly or backwards it will be difficult for boats
without engines and more expensive on fuel for those with engines.
Velocity can also affect safety of boats.
Possible question alternatives.
Starting point
1
2
3
4
5
6
7
8
Methods
Skills
Interpretation
Conclusions/Evaluation
What are the
advantages and
disadvantages of
the analysis
technique(s) that
you used?
Outline and
justify the use of
one or more
techniques used
to statistically
analyse your
results
Name one
technique of data
analysis and
describe how it
was used
How far did your fieldwork
conclusions match the
geographical theory,
concept or idea on which
your study was based
Outline the aim
and describe the
theory, idea or
concept from
which your aim
was derived
Explain the
geographical
concept, process
or theory that
underpinned
your enquiry
Outline and
justify one
method of data
collection that
you used
Describe one
method used to
present your data
Examine the
limitations of
your chosen
methodology
Describe one
application of ICT
skills in carrying
out your fieldwork
and comment on
its usefulness
Outline one
source of
information that
you used and
assess the
extent to which
it was “fit for
purpose”
Explain how you
devised your
aim and how
you responded
to the risks
associated with
your chosen site
for fieldwork
Describe the
location of your
fieldwork and
explain why it
was suitable for
your
investigation
Describe the
purpose of your
fieldwork
enquiry
Outline one
hypothesis and
describe one
methodology for
primary data
collection in
relation to this
Describe and
illustrate one
technique you
used to present
data in this
enquiry
How did you
respond to risks
associated with
undertaking
primary data
collection
What difficulties
did you face when
presenting your
results?
What is meant by
the term
‘significance’ in
the analysis of
fieldwork data?
In what ways would your
conclusions be of use to
other people?
Discuss the
strengths and
weaknesses of
the method of
data collection
Describe a method
of presentation
that you used in
your investigation
and indicate how
the chosen
method was useful
Outline one
technique that you
have used to
present results
from your data
collection
In the context of
the analysis of
fieldwork data,
outline the
meaning of
‘anomalies’.
Drawing upon your
findings, explain how your
enquiry improved your
understanding of the topic
area
Describe one
method you used
to present data
collected in your
fieldwork
investigation
Comment on the strengths
and weaknesses of
different aspects of the
study and suggest
improvements
With the aid of a
diagram, describe
one technique that
you used to
present data in
your enquiry
Explain how the
use of ICT can
improve
geographical
understanding
Summarise the main
findings of your
investigation
With reference
to fieldwork
investigations
distinguish
between
qualitative and
quantitative
data
Describe the
characteristic
features of your
study area
Comment on the
strengths and
weaknesses of
different aspects
of the study.
Suggest
improvements.
In the box
provided, draw
and annotated
sketch map of the
location of the
study area to
show the basic
characteristics
Summarise your findings
and suggest how this
enquiry could be improved
Making specific reference
to your results, suggest
how your enquiry could be
improved
Methods Sketch
Results table
Site (x)
(increasing
distance
downstream)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
Rank x
14
13
12
11
10
9
8
7
6
5
4
3
2
1
Average
Velocity (y)
(m/sec)
0.59
0.24
0.62
0.39
1.01
0.91
0.98
0.17
0.47
0.11
0.04
0
-0.10
-0.23
Rank y
5
8
4
7
1
3
2
9
6
10
11
12
13
14
d
9
5
8
4
9
6
6
-2
0
-5
-7
-9
-11
-13
∑d²
d²
81
25
64
16
81
36
36
4
0
25
49
81
121
169
788
Scattergraph with flow backwards still counted as a + velocity
Correlation coefficient: -0.65
Critical value (99% confidence level): 0.646
n= 13
Still a negative correlation
Scatter graph without last three sites
Correlation coefficient: -0.57
Critical value (99% confidence level): 0.73
n= 11
This shows is still negative, but no longer a significant correlation