RIVER LANDSCAPES IN THE UK

Question 1

What are the four processes of erosion?

Answer 1

HYDRAULIC ACTION-Breaks rocks away from the river channel

ABRASION-Scrape and rub against the channel

ATTRITION-Smash into eachother

SOLUTION-River water dissolves(chalk)

Question 2

What are the four processes of transportation?

Answer 2

TRACTION
SALTATION
SUSPENSION
SOLUTION

Question 2

What are the four processes of transportation?

Answer 2

TRACTION-Large particles are pushed along the river bed
SALTATION-Pebble sized rocks bounce
SUSPENSION-Small particles get carried along by water
SOLUTION-Soluble material dissolve

Question 3

WHY DO RIVERS DEPOSIT

Answer 3

1) Volume of water falls
2) Amount of eroded material increases
3) The water is shallower
4) The river reaches the mouth

Question 4

WHAT THREE LANDFORMS ARE FOUND IN THE UPPER COURSE

Answer 4

Waterfalls,Gorges, Interlocking Spurs

Question 5

HOW ARE WATERFALLS AND GORGES FORMED

Answer 5

1)Waterfalls form when a river flows over 2)HARD ROCK followed by SOFT ROCK
SOFTER ROCK is eroded (HA and ABRASION)creating a STEP
3)When water goes over a step it eroded more
4)A steep drop is eventually formed WATERFALL
5)Hard rock is UNDERCUT by erosion it becomes unsupported and collapses
6)COLLAPSED rock SWIRL around at the foot of the waterfall where they erode by ABRASION-creates a plunge pool
7)Overtime more undercutting and collapses Waterfall will retreat leaving a steep-sided GORGE

Question 6

INTERLOCKING SPURS

Answer 6

1) Most erosion is vertical
2) Creates steep sided V-Shaped valleys
3) Aren’t powerful enough to erode laterally so wind around high hillsides
4) Create interlocking spurs

Question 7

HOW ARE MEANDERS FORMED?

Answer 7

By EROSION and DEPOSITION
River develops large bends called meanders in middle and lower course due to shallow and deep sections
1)Current is faster on the outside (River is deeper-Less friction to slow it down)
2)SO more erosion takes place on outside- RIVER CLIFF
3)Correct is slower on the inside (River is shallower-More friction to slow it down)
4)Material is deposited on the inside -SLIP OF SLOPES

Question 8

How are Ox-bow lakes formed?

Answer 8

Oxbow lakes
Ox bow lakes are formed when meanders get bigger
Erosion causes the bend to get closer
Untill there is only a small bit of land left
The river breaks through this bit of land usually in a flood
And then the river takes the shortest course
And eventually deposition cuts of the meander leaving an oxbow lake

Question 9

How are flood plains formed

Answer 9

Flood plains are formed in the lower course in the flat areas of land
Usually gets flooded
When water floods on floodplain water slows down and deposits
Meanders migrate across floodplains

Question 10

What are leeves and give and example

Answer 10

Leeves are natural embankments along edges of the river channel
During a flood eroded material is deposited over the flood plain
Heaviest is deposited first
Builds up eg. YELLOW RIVER IN CHINA

Question 11

What are esturies give an example

Answer 11

Estuaries are found at the mouth of a river where it meet the sea
They are tidal
Widest
The water floods over the banks
Sediment is deposited making mudfalts
At low tide they are exposed
Eg.Severn Estuary

Question 12

Name a UK River

Answer 12

River clyde

Question 13

How long is the river Clyde?

Answer 13

160 km in Scotland

Question 14

What features does river Clyde have?

Answer 14

Estuary at Glasgow (3km wide)
Floodplain at Glasgow
Meanders near Glasgow
Interlocking Spurs at Crawford
Four waterfalls near Lanark
Ox-bow lake in New Lanark areap

Question 15

WHAT DO HYDROGRAPHS SHOW

Answer 15

show how the discharge at a river changes overtime

Question 16

WHY DOES LAG TIME HAPPEN

Answer 16

Most rainwater doesn’t land directly in the river channel there is a delay as rainwater gets channeled

Question 17

WHY DO RIVERS FLOOD

Answer 17

PROLONGED RAINFALL- After long period of rains, soil becomes satuated and then rain can’t infiltrate

GEOLOGY- some rocks are impermeable eg. Granite runoff is increased

HEAVY RAINFALL- Water arrives too rapidly for infiltration increases discharge

RELIEF- steep sides ballet water will reach the channel the quicker

LAND USE- Building are made from impermeable materials eg. Concrete
Roads made of tarmac
Trees

Question 18

WHAT ARE HARD ENGINEERING

Answer 18

Dams and reservoirs-
Channel straightening
Embankments
Flood relief channels

Question 19

WHAT ARE SOFT ENGINEERING

Answer 19

Flood warnings
Preparation
Flood plain zoning
Planting trees
River distoration

Question 20

What is a flood management case study

Answer 20

BOSCASTLE

Question 21

Why did Boscastle flood?

Answer 21

16th August 2004
Flash floods- no modern flood defences
Surrounded by steep valley sides
Land upstream has been cleared of vegetation- increase runoff
Old bridge has a low arch-narrow channel
Trees became trapped
Village is popular tourist destination 90% of economy relied on tourism tourism dropped significantly

Question 22

What strategies where in the flood management scheme

Answer 22

HARD ENGINEERING
1)New flood wall
2)River embankment has been strengthened
3)River channel widened
4)A gauge introduced to monitor water levels
5)Old bridge replaced with a higher bridge
6)Car park has been raised
SOFT ENGINEERING
1)Dead trees and veg removed to stop them blocking

Question 23

What are social issues?

Answer 23

1) Residents were disrupted
2) safer place
3) Only protect against 1 in 75 year flood
4) Many residents don’t like the new bridge ruins the character

Question 24

What are economic issues?

Answer 24

1) Homes and businesses are less risk at flood- less expensive damage
2) Cost over £4 million- to expensive

Question 25

What are environmental issues?

Answer 25

1) vegetation and river habitats- biodiversity have improved