Physical Fieldwork - Epping Forest Flashcards
What is velocity?
The speed of an object in a given direction
What is bedload size?
The magnitude of particles in a river that are transported along the bed
What is channel width?
The lateral extent of the river meanders
What is channel depth?
The distance from the surface of the water to the surface of the river bed
What is ‘downstream’?
The direction towards the mouth of the river, in which the current flows
What was the aim of the investigation?
To explore how river characteristics change with distance downstream along Debden Brook
What was the justification of the aim?
Based on Bradshaw’s Model which predicts the change in river characteristics with distance downstream
Exploration of the truth of these hypotheses and the extent to which we expect each characteristic to change
Where is Debden Brook located?
It is in Essex, near Loughton in South East England and 9km away from Central London
Describe Debden Brook
It is 4km long and has its confluence with the River Roding with the source of the river being Furze Ground
The river covers 7897 acres and is part of the River Thames drainage basin
Why did we choose this location?`
It is close - reducing travel cost and time
Debden Brook is short - easily travel to 3 varying parts of the river in a short amount of time
Safe and accessible - it’s relatively narrow, not too deep and had a workable velocity
What were the subjects of the hypotheses?
Velocity
Channel size (width and depth)
Bedload size
Bedload shape
What was the velocity hypotheses and justification?
Velocity will increase with distance downstream
Increased channel width, depth and multiple tributaries means more water can travel downstream at a quicker rate
This means there is less contact with the river bed and less energy used to overcome friction
What was the channel width hypotheses and justification?
Channel width will increase with distance down stream
Due to lateral erosion which forces particles laterally into the river bank, widening it
What was the channel depth hypotheses and justification?
Depth will increase with distance downstream
Because of vertical erosion which forces particles vertically into the river bed, lowering it
What was the bedload shape hypotheses and justification?
Particles will become more spherical in shape with distance downstream
The constant erosion (attrition, abrasion, saltation and traction) of the particles will make them more round in shape
What was the bedload size hypotheses and justification?
Bedload size will decrease with distance downstream
The repeated erosion will wear away the particles, decreasing their size
What is the teacher risk assessment of drowning?
Concern: teacher
Risk: low
Consequence: death or injury
Prevention: ensure river is shallow, students can swim or are supervised and wearing appropriate footwear
What are the factors to consider when preparing a risk assessment?
Hazard / event
Concern of who?
Risk level
Consequence
Action to be taken to reduce risk
Action to be taken in event of occurrence
What is the student risk assessment for drowning?
Concern: student
Risk: low
Consequence: injury or death
Prevention: listen to instructions (eg: when to get in or out) and wearing appropriate footwear for walking in a river
In case of the event: alert a teacher who will call 999
What is the risk assessment for a crash for travelling to the location?
Event: crash
Concern: teacher
Risk: low
Consequence: injury or death
Prevention: choosing a reputable coach company
In case of event: call 999 and find a safe location to stand and wait for help
What is the risk assessment of Weil’s disease?
Concern: student
Risk: low
Consequence: sickness
Prevention: avoid drinking river water, cover wounds with blue tape and wear gloves
In case of event: go to the hospital
What is the risk assessment for slips, trips and cuts?
Concern: student
Risk: medium
Consequence: injury (cuts)
Prevention: walking slowly, wearing willies to reduce likelihood of cuts and watching where you walk
In case of event: use a first-aid kit to clean up and then apply a plaster
What is the risk assessment for crossing the road?
Event: being hit by a car
Concern: teacher
Risk: medium
Consequence: injury or death
Prevention: follow the FSC road crossing protocol
In case of event: call 999
What is the risk assessment for the weather?
Concern: student
Risk: medium
Consequence: wet clothes, fever (too cold or too hot)
Prevention: wear sensible clothing and bring spare clothing
What is methodology?
How data is collected (ie: data collection)
How was the depth of Debden Brook measured?
Tape measure held taut to measure the width of the river
Depth taken at 1/4, 1/2 and 3/4 across the width of the river
Depth was measured with a 30 cm rule perpendicular to the surface and noted down in metres
Why was the depth of the river measured this way?
To measure the cross-sectional area
Which allowed us too see whether the depth of the river changed with distance downstream
What were the benefits of measuring the river depth this way?
Simple method to use
Allows a depth measurement at 3 points (easily spot anomalies and can draw a cross-sectional diagram)
Allows for a comparison of different sites downstream
What were the drawbacks of measuring river depth this way?
Human error in measurements could skew results
3-point cross-section is too limited of a data range
Shallow river was difficult to measure
How was the width of the river measured?
Tape measure used to measure from river bank to the other river bank
Tape measure was held taut to improve the accuracy and precision of reading
