Year 10 Rivers

Question 1

Erosion in the upper course

Answer 1

Hydraulic action and attrition. Mostly vertical erosion

Question 2

Erosion in the middle course

Answer 2

Mostly attrition and a little hydraulic action. Less vertical erosion, lateral erosion begins

Question 3

Erosion in the lower course

Answer 3

Erosion is reduced some lateral erosion on the outside bends of rivers

Question 4

Transport in the upper course

Answer 4

Mostly large boulders, little in solution. Traction is most dominant

Question 5

Transport in the middle course

Answer 5

Smaller sized bedload little in solution. Saltation dominated

Question 6

Transport in lower course

Answer 6

Smaller sized bedload of pebbles, gravel and sand for the load. Most transport by suspension

Question 7

Deposition in the upper course

Answer 7

Limited due to large bedload

Question 8

Deposition in the middle course

Answer 8

Coarser material builds up, deposition on slip off slopes. Floodplain build up in times of flood

Question 9

Deposition in lower course

Answer 9

Mostly fine particles, forms slip off slopes, leeves and flood plains

Question 10

Gradient in upper course

Answer 10

Steep

Question 11

Gradient in middle course

Answer 11

Less steep

Question 12

Gradient in lower course

Answer 12

Grendel gradient/ flat

Question 13

Associated landforms in the upper course

Answer 13

Steeped narrow, v shaped valley, waterfalls/ Rapids, interlocking spurs

Question 14

Associated landforms in the middle course

Answer 14

Open v- shaped valley, waterfalls/Rapids, meanders/ox bow lakes, braiding

Question 15

Assassinated landforms in the lower course

Answer 15

Wide gentle sided valley, flood plains, knick points, leeves, river terraces, meanders, ox bow lakes braiding

Question 16

How is a waterfall formed

Answer 16

When a river passes over harder rock (wintstone) which is on top of softer rock, the softer rock is eroded faster by abrasion and hydraulic action. This creates and overhang and cracks appear in the wintstone. The overhang collapses and the wintstone fills in the plunge pool. This process continues to happen and the waterfall retreats upstream and forms a steep sided gorge

Question 17

In the middle course, why does the river have more energy and a high volume of water

Answer 17

Because the tributaries have joined and there is more water from through-flow and surface runoff.

Question 18

How is a levee formed

Answer 18

During floods water is slowed at banks and silts are deposited. In between floods slow moving water deposits silt in water bed. The levees are built up with each flood and the river bed is built up too. The amount of water stays the same

Question 18

Wheat is an estuary

Answer 18

An area where fresh water, river or stream meets the ocean, this results in brackish, somewhat salty water

Question 18

Characteristics of a flashy response river

Answer 18

Short lag time, steep rising and falling limb, returns to normal quickly, high peak discharge, most likely to cause flood

Question 18

What causes a flashy response

Answer 18

Basin with impermeable rock- flows after over ground
Urbanised catchment- artificial drains and tarmac so water will flow faster
Basin with steep sides- water will flow faster
Short heavy rainfall

Question 18

Characteristics of a slow response

Answer 18

Long lag time, low peak discharge, gentle rising and falling limbs, returns to normal slowly, less likely to cause a flood

Question 18

What causes a slow response

Answer 18

A forested catchment- more interception
Has a dam- slows down the flow
Shallow sided basin- more water is absorbed into the ground
Basin with permeable rock

Question 18

Human causes of flooding

Answer 18

Deforestation

Construction work

Question 18

Physical causes of flooding

Answer 18

Prolonged rainfall Heavy rain Snowmelt Steep relief

Question 18

Examples of hard engineering

Answer 18

Channel straightening Dredging Dams Levees

Question 18

Examples of soft engineering

Answer 18

Afforestation Flood warnings Floodplain zoning

Question 18

Advantages and disadvantages of afforestation

Answer 18

Cheap, improves appearance, areas for wildlife to develop, no risk of people losing their homes Takes long time, plants could be damaged in bad weather, won't work in storms, only controls small area of rivers

Question 19

Advantages and disadvantages of flood warnings

Answer 19

Allows time to prepare for flood, valuables can be taken with the people so less cost, easily spread through TV, radio etc Doesn't stop flood, people may not have access to warnings, elderly or disabled unable to react in time

Question 20

Advantages and disadvantages of floodplain zoning

Answer 20

Water can reach river at natural speed, homes and schools and built on land that is prone to flood, flood ares are left vacant Expansion of urban areas near river is limited, doesn't help houses that have already been built

Question 21

Advantages and disadvantages of dams and reservoirs

Answer 21

Can create hydro electric power, last for decades, can store water for drinking and leisure activities Expensive, takes time, spoils landscape, can be deadly of it fails

Question 22

Advantages and disadvantages of levees

Answer 22

Quick to build, used as a temporary method, removed easily | Water can't always drain away, look ugly, not always reliable, wear away if made of mud

Question 23

Advantages and disadvantages of channel straightening

Answer 23

Makes water flow at much faster rate, reduces level of erosion occurring at meanders, speeds up water Lead to flooding further downstream, expensive, takes a long time, damages habitats and ecosystems

Question 24

Advantages and disadvantages of dredging

Answer 24

Increases river capacity, doesn't affect appearance, used at specific locations Deposition will build up after a certain time, expensive, time consuming, loss of marine life and wetlands

Question 25

Management in upper course of tees

Answer 25

Cow green reservoir built in 1970 water for growing industries. Regulating reservoir Expensive habitats were destroyed Large areas flooded when building

Question 26

Management in middle course of Tees

Answer 26

After flood in Yarm in 1995 £2.1 million spent on building reinforced concrete walls with flood gates Earth embankments and Fabian's installed

Question 27

Management in lower course of Tees

Answer 27

£1.2 million allocated to flood defence schemes at Lustrom Beck 150 properties affected in 2012 flood Tees barge built and dredging took place