Controlled Assessment Data Presentation

What do the examiners say?

Hypotheses

1. Channel size or Cross Sectional area will increase with distance downstream.

2. Channel efficiency will increase with distance from the source.

3. Channel gradient will decrease with distance downstream.

Essential Graphs1. Channel cross sections of your own groups 4 sites.2. Graph to show downstream change in Cross Sectional

Area (all 12 sites)3. Graph to show downstream change in channel

efficiency (all 12 sites)4. Graph to show downstream changes in channel

gradient (all 12 sites)5. Pie chart to show downstream Average Powers Score at

12 sites. Powers data could also be shown as pie charts for your own groups results (4 sites)

Are there photographs that will support your data presentation?

From your photos find 10 images that you could use as part of your data presentation

Cross Sectional Areas - Drawings

You will need to draw a channel cross section graph for each of your own groups 4 sites.

These should be presented on graph paper and should be to scale.

Cross Sections drawn to Scale

Deciding on ScaleWidth - (x axis) 1 metre = 2 squares on graph paper or

….cmso a 3 metre river will have a width of six squares on the

graph.Depth - (y axis) 1 metre = 10 squares or …..cmso a depth of 70 cm will be 7 squares or ...cm on the

graph.depth intervals- divide width by 11.

Fig 3.3 River Channel Cross section - Site1 - Upper Course.

Annotated site photo

.010m/s

0.22m/s

0.01m/s

Channel Efficiency

Student Examples of Sophisticated Channel Cross Section – Upper Cousre

Student Examples of Sophisticated Channel Cross Section – Middle Cousre

Making your cross sections more sophisticated.

• Adding text to describe the shape of the channel.

• Calculating and commenting on channel efficiency. of the channel.

• Adding velocity data across the channel.

• Plotting bedload on the bottom of the channel by using proportional circles to show powers score for each 10 pieces of bedload.

Cross Sectional Area - Trend

1 2 3 4 5 6 7 8 9 10 11 120.00

2.00

4.00

6.00

8.00

10.00

12.00

14.00

Cross Sectional Area - Trend

1 2 3 4 5 6 7 8 9 10 11 120.00

2.00

4.00

6.00

8.00

10.00

12.00

14.00

Cross Sectional Area of River Channel Downstream

Sites

Cros

s Sec

tiona

l Are

a (m

²)

LEGEND

Upper Course

Middle Course

Lower Course

Fig: 3.1

Now it’s your turn!

Draw a bar chart to show downstream change in channel efficiency over the 12 sites.

Sophisticated Graphs

Bedload

Comparing Data

1 2 3 4 5 6 7 8 9 10 11 120

5

10

15

20

25

0.00

0.05

0.10

0.15

0.20

0.25

0.30

Average Channel Velocity against Channel Gradient downstream

Channel Gradient Linear (Channel Gradient) Average Velocity Linear (Average Velocity )

Sites

Grad

ient

(°)

Velo

city

m/s

Other graphs may be applicable

A scattergraph could be used if you do a spearman rank coefficient of correlation to show downstream site and CSA.