Topic 4 - The UK's Evolving Phiscal Landscape

Question 1

What is a peak?

Answer 1

Peak-the highest amount

Question 2

What is a discharge?

Answer 2

Discharge-volume of water in the channel at one point

Question 3

What is a rising limb?

Answer 3

Rising limb-shows rising water after rainfall.

Question 4

What is lag time?

Answer 4

Lag time-difference between peak rainfall and peak discharge

Question 5

What is falling limb?

Answer 5

Falling limb-shows discharge falling as less water reaches the channel.

Question 6

What is a storm hydro graph?

Answer 6

A storm hydro graph shows how the discharge of a river changes over time;we use them to see how the river responds to rainfall events showing 2 things: rainfall (bars) and discharge (line).

Question 7

What is the river course?

Answer 7

River course-the path of a river as it flows downhill is called its course.

Question 8

What is upper course?

Answer 8

Upper course-rivers have an upper course (closest to the source of the river). Steep gradient with ‘v’ shaped valley, steep sides, narrow and shallow channel.

Question 9

What is middle course?

Answer 9

Middle course-In between an upper and a lower course. Medium gradient with gently sloping valley sides. Wider deeper channel.

Question 10

What is lower course?

Answer 10

Lower course-closest to the mouth of the river. Gentle gradient, very wide almost flat valley. Very wide, deep channel.

Question 11

What is river channel?

Answer 11

River channel-Rivers form channels as they flow downhill. The shape of the channel changes along the river depending on whether erosion or deposition is having the largest impact. They are ‘v’ shaped.

Question 12

What is long profile?

Answer 12

Long profile-shows you how the gradient (steepness) changes over the different courses.

Question 13

What is cross profile?

Answer 13

Cross profile-shows you what a cross-section of the river looks like.

Question 14

What is river discharge?

Answer 14

River discharge-the volume of water flowing in a river measured in metres cubed/second or cumecs.

Question 15

What is vertical erosion?

Answer 15

Vertical erosion-this deepens the river valley (and channel), making it ‘v’-shaped. Its dominant in the upper course of the river. High turbulence causes the rough, angular particles to be scraped along the river bed causing intense downwards erosion.

Question 16

What is lateral erosion?

Answer 16

Lateral erosion-widens the river valley (and channel) during the formation it meanders. Dominant in the middle and lower course of the river.

Question 17

What is the Bradshaw model?

Answer 17

The Bradshaw model summarises the changes to river characteristics from source to mouth down the long profile. Five features increase downstream three decrease downstream.

Question 18

Does river discharge increase or decrease downstream?

Answer 18

Increases as yo go downstream

Question 19

Does the channel width increase or decrease downstream?

Answer 19

Very wide downstream

Question 20

Does channel depth increase or decrease downstream?

Answer 20

Shallow downstream

Question 21

Does velocity increase or decrease downstream?

Answer 21

The velocity increases as there is less friction.

Question 22

Does sediment load size increase or decrease downstream?

Answer 22

Decreases downstream in size.

Question 23

Does sediment particle shape decrease or increase downstream?

Answer 23

Gets smoother downstream.

Question 24

Does slope angle (gradient) increase or decrease downstream?

Answer 24

Becomes less steep as you go downstream.

Question 25

Does river discharge increase or decrease downstream. Give reasons.

Answer 25

As rivers join to the lower course the sediment merges creating lots of discharge as they all have different courses.

Question 26

Does channel width increase or decrease downstream. Give reasons.

Answer 26

Lateral erosion downstream causes the rivers to be wide. As the river meanders there is lots of abrasion and hydraulic action due to its high velocity.

Question 27

Does channel depth increase or decrease downstream. Give reasons.

Answer 27

The upper course of the river experiences deep vertical erosion as the rocks in the water are rough and angular. This means that it is deeper than downstream.

Question 28

Does velocity increase or decrease downstream. Give reasons

Answer 28

The velocity in the lower course of the river is slower than the upper course as it has smooth sides, the upper course has rough sides slowing it down.

Question 29

Does sediment load size increase or decrease downstream. Give reasons.

Answer 29

The size of the sediment decrease because it gets worn down by the erosion on the walls of the channel. It also breaks apart when they hit each other continuously.

Question 30

Does sediment particle shape increase or decrease downstream. Give reasons

Answer 30

Due to erosion on other rocks breaks down sediment causing its originally jagged edges to smooth down into curves.

Question 31

Does slope angle (gradient) increase or decrease downstream. Give reasons

Answer 31

Due to higher lateral erosion the small rocks eroding the sides of the channels makes the rocks at the sides wide.