4.6, 4.7, 4.8

Question 1

Long profile of a river

Answer 1

The path of a river, and how it has elapsed from start to end. Twisting, bending, meandering, eroding downward, depositing sediment causing higher floor etc.

Question 2

Hydraulic action vs abrasion

Answer 2

Hydraulic action is when high pressure water jets are pushed into cracks and faults, causing pressure on the rock making the fault larger.

Abrasion uses scraping of sediment, to erode rock instead of water under high pressure.

Question 3

Weathering

Answer 3

The process occuring when different weather types of weather are present in a landscape, causing specific visual and physical effects on the landscape.

Question 4

Freeze thaw vs biological

Answer 4

Freeze thaw is when water fills faults or cracks, freezes and increases the width of the fualt or crack.
Biological weathering is when plants seed in areas prone to erosion, the grow and cause cracks and instability, falling of rock and erosion.

Question 5

Traction vs suspension.

Answer 5

Traction is sediment being carried along the river bed, rolling along the direction of the flow. Usually larger sediment.
Suspension is when the sediment bounces off the river bed, suspended in the flow of water being carried along, usually smaller pieces of sediment.

Question 6

Waterfalls

Answer 6

A area of soft rock in the river bed is eroded, because of erosion of traction, a area of deeper river bed arises and the water falls of the lip created, eventually the plunge pool below will become deeper because of the sediment and rocks falling into it, deepening it, causing a steeper water fall. As the waterfall lip erodes, it will eventually fall and cause retreating in the waterfall, giving the effect of a cut waterfall back in the landscape.

Question 7

V shaped valley

Answer 7

Begins with a river flowing through a landscape, which erodes deeper into the landscape, the raised embankments of the river become loose due to weathering and collapse, the fallen sediment is taken away don the river and a v shape is left behind to the valley.

Question 8

Lag time

Answer 8

Time between maximum rainfall and peak discharge of river. Time for people to evacuate the areas in risk from warning

Question 9

Physical factors affecting hydrographs

Answer 9

Steepness of drainage basin, permeability of soil, surrounding landscapes, speeding up or slowing down lag time.

Question 10

Deforestation and urbanisation affecting flood hydrographs.

Answer 10

Land characteristics change, permeability of concrete is low, primarily used in urbanised areas, faster run off time, less lag time. Trees slow surface run off, deforestation means less obstacles obstructing the surface run off, meaning faster run off and faster lag time.

Question 11

How can humans affect flooding, how did it in the river Eden case?

Answer 11

Physical- heavy rainfall, causing floodwater in large ammounts,

Human
-poor drainage systems and sewers couldn’t cope and caused worsened flooding in urbanised areas.

Question 12

Flooding probems

Answer 12

-death
-loss of property
-loss of business
-worsened economy
-tourism lost
-natural attractions, (attractions) lost
All link together

Question 13

Why is river flood increasing?

Answer 13

Climate change means global climate is heating up, this is because of a few different factors such as greenhouse gasses which trap heat, amplifying it, consequently, ice is melting, making sea levels rise and a lower tolerance of most rivers, due to higher water levels and more risk of flooding.

Question 14

Hard vs soft engineering

Answer 14

Hard- using non natural materials in to stop natural pricesses.
Soft- using natural material and usually less visually destructive to landscapes, enhancing natural processes.

Question 15

Levees

Answer 15

Look bad
Can be expensive

Stop over flowing rivers
In cases where they aren’t tall enough, they will cause worse more sudden, severe flooding

Question 16

Dredging

Answer 16

Need to be re dredged anually-expensive

Natural and not easy to see
Fairly inexpensive to do the process.

Question 17

Using wood and natural things to slow river flow

Answer 17

Inexpensive,
Effective
Slows river flow, decreasing flooding chances
Natural

Question 18

The landscapes change through the flow of river Eden

Answer 18

The higher section of the river is steeper, in the middle course it evens out and increases velocity, in the lower course, the river branches out and increases velocity, due to less obstructions.

Question 19

Reasons for changes to the landscape

Answer 19

Valley sides affected by river flow
Rounder rocks are found in the upper course as they have had less erosion whereas in the middle and lower course the sediment is smaller as it has been more finely eroded.

Question 20

Upper course

Answer 20

The source of the Eden is about is about 600m abouve sea level. In an area of hard, resistant rock.

Question 21

River erosion

Answer 21

Can be vertical and lateral, takes easiest path of erosion, softest rock and forms shape of river.

Question 22

Confluence

Answer 22

Confluence - the point at which two rivers or streams join. Tributary - a stream or smaller river which joins a larger stream or river.

Question 23

Ox bow lake

Answer 23

Tight meander has a neck of soft rock, high velocity of water on the outside of the river causes it to erode through, leaving a cut out area of water, where the meander outside used to be and leaves a pool of water that becomes stagnant, sediment is deposited here and cuts it off from the flow of the main river altogether and it is isolated as a ox bow lake.

Question 24

Meander

Answer 24

A bend in the flow of a river, where the flow of water is at optimum velocity in the outside of the bend

Question 25

Interlocking spurs

Answer 25

Glaciers in a period of ice age, melt away soft rock from a mountainous area which alternated through the now valley, soft and hard rock. The soft rock was taken away by freeze thaw, leaving interlocking hard rock strips either side, the river follows this pattern and these bends created when it follows the interlocking pattern, are not called meanders.

Question 26

Saltation

Answer 26

Sediment dissolved in the water and carried as molecules suspended near the surface of the water.