AQA AS Geography Fieldwork Ashes Hollow
AS Fieldwork Report
Introduction
Aim
To investigate the downstream changes in channel variables at Ashes Hollow Stream.
Hypothesis
“Discharge increases with Distance from Source”
Location and description of the location
Ashes Hollow Stream is an area fairly untouched by human activity, with safe, easy access and the Stream is shallow due to being in the Upper Course of the river.
Methodology
Risk Assessment
Hazard
Likelihood
Impacts
Severity
Risk
Mitigation
Slipping Over
3
Sprains, Bruises
2
6
Wear suitable footwear, act sensibly
Diseases and Illness
1
Death, Weil’s Disease
3
3
Wash Hands, Wear Gloves
Inclement Weather
3
Get Wet, Cold, Hypothermia
3
9
Plenty of layers, Waterproof coat
General safety tips;
Take mobile phone and leave contact details
Work in groups
Tell someone how long you are going to be
Sampling Strategy
We used Stratified sampling because we thought it would give us the biggest changes in regards to our hypothesis. To do this we chose a sample area both before and after 4 separate confluences on Ashes Hollow.
Cross Sectional Area
Needed to calculate discharge; Q = CSA x V
1. Measure the width of the stream, using a tape measure. Make sure the tape is taught and 90˚ to the bank, avoiding the overhanging bank.
2. Divide the width by 10 (to give a systematic sample). Then measure the depth using a meter ruler, orientating the ruler parallel to the stream flow to minimise drag.
3. Calculated the mean depth and multiply by the width to get average CSA.
4. Pros: Gives an estimate of CSA and allows comparison downstream.
5. Cons: Bedload caused problems getting true reading of depth.
Velocity
Needed to calculate discharge; Q = CSA x V
1. The hydro prop was placed in the water and the time taken for the impeller to travel the distance of the rod was taken.
2. This measurement was repeated at 3 equidistant places across the river and an average time taken. The velocity was calculated using the equation:
Introduction
Aim
To investigate the downstream changes in channel variables at Ashes Hollow Stream.
Hypothesis
“Discharge increases with Distance from Source”
Location and description of the location
Ashes Hollow Stream is an area fairly untouched by human activity, with safe, easy access and the Stream is shallow due to being in the Upper Course of the river.
Methodology
Risk Assessment
Hazard
Likelihood
Impacts
Severity
Risk
Mitigation
Slipping Over
3
Sprains, Bruises
2
6
Wear suitable footwear, act sensibly
Diseases and Illness
1
Death, Weil’s Disease
3
3
Wash Hands, Wear Gloves
Inclement Weather
3
Get Wet, Cold, Hypothermia
3
9
Plenty of layers, Waterproof coat
General safety tips;
Take mobile phone and leave contact details
Work in groups
Tell someone how long you are going to be
Sampling Strategy
We used Stratified sampling because we thought it would give us the biggest changes in regards to our hypothesis. To do this we chose a sample area both before and after 4 separate confluences on Ashes Hollow.
Cross Sectional Area
Needed to calculate discharge; Q = CSA x V
1. Measure the width of the stream, using a tape measure. Make sure the tape is taught and 90˚ to the bank, avoiding the overhanging bank.
2. Divide the width by 10 (to give a systematic sample). Then measure the depth using a meter ruler, orientating the ruler parallel to the stream flow to minimise drag.
3. Calculated the mean depth and multiply by the width to get average CSA.
4. Pros: Gives an estimate of CSA and allows comparison downstream.
5. Cons: Bedload caused problems getting true reading of depth.
Velocity
Needed to calculate discharge; Q = CSA x V
1. The hydro prop was placed in the water and the time taken for the impeller to travel the distance of the rod was taken.
2. This measurement was repeated at 3 equidistant places across the river and an average time taken. The velocity was calculated using the equation: