UK physical landscapes : River Landscapes in the UK Flashcards
(270 cards)
1
Q
Define abrasion
A
rocks carried along by river, wearing down bed and banks
2
Q
Define attrition
A
rocks carried along by river, smashing together into smaller, rounder pieces
3
Q
Define discharge
A
quantity of water passing point within time period
4
Q
Define estuary
A
tidal mouth of river where it meets sea
5
Q
Define gorge
A
narrow, steep sided valley
6
Q
Define hydraulic action
A
force of river against banks cause air to be trapped in cracks and crevices
7
Q
Define interlocking spurs
A
series of ridges on alternate sides of valley around river
8
Q
Define lateral erosion
A
sideways erosion by river on outside meander channel
9
Q
Define meander
A
pronounced bend in river
10
Q
Define ox bow lake
A
arc shaped lake cut off from meandering river
11
Q
Define precipitation
A
moisture falling from atmosphere
12
Q
Define traction
A
rolling of boulders and pebbles along river bed
13
Q
Define vertical erosion
A
downward erosion of river bed
14
Q
Define waterfall
A
sudden descent of river over vertical slope
15
Q
On a global cycle the hydrological cycle is…
A
…a closed system
16
Q
What does a closed system mean?
A
nothing can leave or enter system
17
Q
On a local scale, the hydrological cycle is…
A
…open system
18
Q
What does an open system mean?
A
inputs and outputs
19
Q
What is a water table?
A
current upper level of saturate rock where no more water can be absorbed
20
Q
What is ground water flow?
A
water flowing through rock layer parallel to surface
21
Q
What is through flow?
A
water flowing through soil layer parallel to surface
22
Q
What is surface run off?
A
water flowing on top of the groun
23
Q
What is evaporation?
A
water lost from ground / vegetation surface
24
Q
What is transpiraiton?
A
water lost through pores in vegetation
25
What is groundwater storage?
water stored in rock
26
What is percolation?
water seeping deeper through rock
27
What is infiltration?
water sinking into soil/rock from ground surface
28
What is surface storage?
water held on ground surface
29
What is interception?
water prevented from reaching surface/ground by trees
30
What is precipitation?
source of moisture reaching ground
31
How does deforestation affect surface run off?
increases speed, less interception
32
How does urbanisation affect ground water?
water cannot be stored, flooding
33
What is the source?
start of river
34
What is the drainage basin?
area of land drained by river and tributaries
35
What is confluence?
where tributary joins to bigger river
36
What is mouth?
end of river
37
What is watershed?
edge of river basin
38
What is tributary?
small stream that joins a larger river
39
How might the characteristics of a drainage basin vary?
size
relief
geology
land use
40
How many courses of a river are there?
3 courses
41
What are the three courses of a river?
upper
middle
lower
42
How does the long profile of a river change from source to mouth?
gradient decreases
43
What is the river valley like in the upper course?
steep
v shaped
44
What is the river valley like in the middle course?
shallow
45
What is the river valley like in the lower course?
flat
46
What is the river channel like in the upper course?
waterfalls
47
What is the river channel like in the middle course?
wider
deeper
meanders
48
What is the river channel like in the lower course?
widest
deepest
most meanders
49
Which landforms occur in the upper course?
interlocking spurs
50
Which landforms occur in the middle course?
meander
ox bow lake
51
Which landforms occur in the lower course?
flood plain
levees
estuary
52
Give examples of fluvial processes
erosion
transportation
deposition
53
Define erosion
wearing away of material
54
Where is the process of erosion most dominant?
upper course
55
How does erosion occur in the upper course of the river?
vertically
56
Why does erosion occur vertically in the upper course?
discharge smallest
rive cutting down to get to sea
rock is most resistant
57
How does erosion occur in the middle course of the river?
laterally
58
Why does erosion occur laterally in the middle course of the river?
material carried by river erodes banks
59
What processes occur in the middle course?
deposition
transportation
erosion
60
Where is deposition most dominant?
lower course
61
Why is deposition the most dominant in the lower course?
losing energy
62
What does vertical erosion mean?
deeper
63
What does lateral erosion mean?
wider
64
Define solution
occurs when water is slightly acidic - dissolves rock
65
What are the four processes of erosion?
hydraulic action
attrition
abrasion
solution
66
What are the four processes of transportation?
traction
saltation
suspension
solution
67
What is the load?
materials carried by river
68
How does discharge effect load?
discharge - more or less load
69
Define saltation
small rocks and particles bounce along river bed
70
Define suspension
fine clay and particles carried along
71
Define solution
minerals dissolve in water - requires little energy
72
What part of load is dropped first?
heaviest
73
When does deposition occur?
flooding
meander
mouth
74
Why does deposition occur when flooding happens?
friction occurs between land - slows river
75
Why does deposition occur at meanders?
loses speed on inside bend
76
Why does deposition occur at mouth?
slows as it hits large body of water
77
Which landforms occur in the upper course?
waterfalls
gorges
v shaped valleys
interlocking spurs
78
Which landforms occur in the middle course?
meanders
ox bow lakes
79
Which landforms occur in the lower course?
levees
flood plain
estuary
mud flat
80
Which processes occur in the upper course?
erosion
81
What is the load like in the upper course?
large
angular
82
Which processes occur in the middle course?
erosion
transportation
83
What is the load like in the middle course?
smaller
rounder
84
Which processes occur in the lower course?
transportation
deposition
85
What is the load like in the lower course?
small
round
86
How do interlocking spurs form?
vertical erosion
- steep sided / v shaped
- lack lateral erosion
- wind round hillsides
87
Water runs over alternating bands of...
...hard and soft rock
88
Erosion will start to break down through....
.....erosional processes
89
What does hydraulic action wear away?
soft rock
90
Why does hydraulic action wear away the soft rock?
less resistant
91
The soft rocks starts....
....to undercut the hard rock
92
hard rock is left...
...unsupported
93
hard rock collapses....
into the river bed
94
Where does erosion occur when forming a waterfall?
upstream
95
Why is inside bend slower of a meander?
it is shallower
96
Why is the inside bend of a meander shallower?
little energy - deposits
97
What is formed as a result of the deposition?
slip off slope
98
What are the other names for a slip off slope?
point bar
river beach
99
Why is the outside bend of a meander faster?
deeper
100
Why is the outside bend deepr?
faster - high energy - hydraulic action / abrasion
101
Which physical factors affect flooding?
geology
saturation
rainfall
land relief
basin size
102
Which human factors affect flooding?
development
climate change
trees
deforestation
agriculture
103
Define flooding
amount of water exceeds - bursts banks
104
What are the characteristics of an oxbow lake?
horseshoe shape
narrow channels
cut off
105
What shape is an oxbow lake?
horseshoe
106
What is the channel of an oxbow lake like?
narrow
107
How does an oxbow lake form?
neck of river broken off
108
What is the first step in the formation of an oxbow lake?
1. water flows over land, outside bend of river
109
What is the second step in the formation of an oxbow lake?
2. river erodes the bank
meander occurs
110
What is the third step in the formation of an oxbow lake?
3. flow on inside bend slows and sediment is deposited
111
What is the fourth step in the formation of an oxbow lake?
4. neck of river grows narrower
112
What is the fifth step in the formation of an oxbow lake?
5. neck of river breaks through, river takes shortest route
113
What is the sixth step in the formation of an oxbow lake?
6. lake sealed off due to deposition
114
Why does an oxbow lake get sealed off?
deposition
115
Why does the neck of the river break?
river will take shortest route and continue straight
116
Why is their lots of deposition on the inside bend?
water moving slower
117
Why does water flow over land and on the outside of the river?
less friction
118
What are the characteristics of a levee?
vegetation
wide
119
Why does a levee high fertility?
deposition of minerals
120
Define levee
raised bank formed on banks of river in lower course
121
How does a levee form?
when river floods, deposits silt
122
When does a levee form?
flooding
123
What part of load is deposited first when forming a levee?
heaviest
124
What part of load is deposited last when forming a levee?
lightest
125
Why is the heaviest part of load deposited first when forming a levee?
not enough energy
126
How does a levee change as flooding becomes more frequent?
levees develop more
127
How does flooding affect the river?
levees build up
river bed build up
128
Define flood plain
area around a large river that is covered in times of flood
129
Describe the characteristics of a flood plain
large
flat
130
What processes form a floodplain?
deposition
erosion
131
How does a floodplain form?
build up of sand, silt and clay formation of flat land either side of river
132
What is the difference between floodplain and levee in terms of characteristics?
levee - raised banks
floodplain - large flat area
133
What parts of the load form a levee compared to a floodplain?
levee - heaviest
floodplain - lightest
134
What is a floodplain covered by during the flood?
excess surface water
135
What shape is an estuary?
fan shaped
136
Define estuary
where the river meets the sea
137
What is the location of an estuary?
coastal
138
How does salinity change down an estuary?
increases
139
How does the channel of an estuary change?
widens
140
Why does an estuary channel widen?
increase capacity
141
Why does salinity increase in an estuary?
meeting sea water
142
Why is material deposited at an estuary?
sea and river meet
tidal processes begin
slows down / lose energy
143
What causes material to be deposited in an estuary?
tidal processes begin
144
How does agriculture affect flooding?
ploughing
cattle farming
145
How does cattle farming affect flooding?
trampling
reduces infiltration of soil
146
How does ploughing affect flooding?
directs surface water
147
How does farming affect flooding?
loss of top soil
-> sedimentation
148
How does climate change affect flooding?
changes rainfall
increases storms
149
What does anthropogenic mean?
human induced
150
How does urbanisation affect flooding?
land useH
151
How does concrete and tarmac affect flooding?
decreases infiltration
increases surface run off
152
What affect does decreasing infiltration have?
increases surface run off
153
What does an increase in surface run off cause?
flooding
154
How does deforestation affect flooding?
decrease in interception
155
Why does deforestation cause a decrease in interception?
parched ground (no shade)
156
Define flooding
amount of water in river exceeds, causing bursting of banks
157
Define discharge
volume of water flowing through river channel CUMECS
158
Why does flooding increase due to urbanisation?
impermeable tarmac
159
Why does flooding increase due to agriculture?
soil left exposed
increase surface run off
160
Why does flooding increase due to deforestation?
reduced uptake
161
Why does flooding increase due to geology/rock type?
impermeable
surface run off increases
162
Why does flooding increase due to basin size?
small - unable to carry water - overflow
163
Why does flooding increase due to soil saturation?
over saturated
increases surface run off
164
Why does flooding increase due to relief?
steep - water moves quickly
- more water enters
165
Why does flooding increase due to precipitation?
flash floods
166
What is the key factor that leads to flooding?
physical
167
Which physical factor affect flooding the most?
precipitation
168
Why does precipitation affect flooding the most?
intensity
duration
frequency
169
How do human factors exacerbate flood risk?
urbanisation
deforestation
agriculture
170
What is discharge measured in?
cumecs
m3/s
171
Name the parts of a hydrograph
falling limb
rising limb
lag time
peak discharge
ground water flow
baseflow
172
What does a hydrograph show?
relationship between precipitation and discharge
173
What is the lag time on a hydrograph?
number of hours between peak discharge and peak rainfall
174
Give the human factors affecting river discharge
urbanisation
agriculture
175
Give the physical factors affecting river discharge
relief
geology
precipitation
176
Why do rivers need to be managed?
flooding
erosion
177
Give examples of hard engineering?
dams
reservoirs
straightening
embankments
flood relief channels
178
Dams and reservoirs are example of what?
hard engineering
179
Straightening and embankments are example of what?
hard engineering
180
Flood relief channels are examples of what?
hard engineering?
181
What is hard engineering?
building artificial structures to control river
182
What is soft engineering?
working with environment to control river
183
Give examples of soft engineering
flood warnings
preparation
flood plain zoning
planting tress
river restoration
184
Flood warnings and preparation are examples of what?
soft engineering
185
Flood plain zoning is an example of what?
soft engineering
186
Planting trees and river restoration are examples of what?
soft engineering
187
What is a dam?
large concrete barrier built across river to hold back flow
188
What affect does a dam have on the valley behind it?
valley behind floods and forms a reservoir
189
How is water released from a dam?
controlled amounts
190
How does a dam prevent flooding?
water controlled and released in monitored amounts
191
What are the economic and social benefits of a dam?
hydroelectric power
drinking water
tourism
192
What are the environmental benefits of a dam?
new wetland habitats
controls discharge
193
What are the economic disadvantages of a dam?
expensive to make
displacement costs
194
What are the environmental disadvantages of a dam?
habitats / migration disrupted
reservoir silts up - decreases capacity
195
What is channel straightening?
meandering section of river is straightened
196
How does channel straightening change the channel?
widened, straightened, deepened
197
How does channel straightening prevent flooding?
river carries more water
water moves faster
198
Where does channel straightening occur?
low lying areas
high risk from flooding
199
What are the social benefits of channel straightening?
navigation increases
200
What are the economic benefits of channel straightening?
insurance premiums reduced
201
What are the economic disadvantages of channel straightening?
expensive to do
maintenance required
202
What are the social disadvantages of channel straightening?
unattractive and unnatural
203
What are the environmental disadvantages of channel straightening?
habitats destroyed
increased flooding downstream
204
What are embankments?
raised river banks
205
How do embankments reduce flooding?
more water contained inside channel
206
How is an embankment made?
bulldozers move large mounds of impermeable soil on to river banks
207
What are the social advantages of embankments?
walkways created
increased capacity
208
What are the environmental advantages of embankments?
habitats created
209
What are the economic disadvantages of embankments?
expensive
210
What are the environmental disadvantages of embankments?
increases severity of flooding if it fails
211
What are the social disadvantages of embankments?
increases severity of flooding if it fails
unattractive and unnatural
212
What is a flood relief channel?
another channel built to deliberately move water away from human settlements during times of high discharge
213
When is a flood relief channel used?
times of high discharge
214
Where do flood relief channels aim to protect?
human settlements
215
What are the social and economic benefits of a flood relief channel?
reduced flooding
recreating
insurance premiums reduced
216
What are the social and economic disadvantages of a flood relief channel?
costly
regular maintenance
habitat destroyed
unattractive and unnatural
217
What is flood watch?
flooding of low lying land and road expected
218
What is flood warning?
threat to homes and businesses
219
What is a severe flood warning?
extreme danger to life and property expected
220
How should people respond to a flood watch?
prepare and watch river levels
221
How should people respond to a flood warning?
move valuable items to upper floors and turn off electric and water
222
How should people respond to a severe flood warning?
leave property
223
What are the economic disadvantages of flood warning?
monitoring equipment
224
What are the social disadvantages of flood warnings?
people may not respond appropriately
225
What are the social benefits of flood warnings?
help people prepare
sustainable
ensures safety
226
How are flood warnings sustainable?
recognises that flooding is a natural event - people must live with it
227
What are the economic disadvantages to floodplain zoning?
restricts economic development
228
How does floodplain zoning restrict economic development?
land uses are prohibited
229
What are the social disadvantages of floodplain zoning?
hard to implement if urban settlement already developed
housing shortages continue
230
What are the environmental disadvantages of floodplain zoning?
habitats destroyed
231
What are the economic advantages of floodplain zoning?
low cost - planning regulations
reduces insurances costs
232
What are the environmental benefits of floodplain zoning?
reduces impermeable surface coverage
protects water meadows and conserves wildlife
233
What is tree planting?
afforestation
234
How does afforestation reduce flooding?
increases interception and uptake
235
How does floodplain zoning reduce flooding?
restricts land use
236
How does flood warning reduce flooding?
reduces affects of flooding
237
How does river restoration reduce flooding?
restores channels to meandering
238
What are the environmental disadvantages of afforestation?
reduce habitat diversity
increased soil acidity
239
What are the social and economic disadvantages of afforestation?
loss of farm land
240
What are the environmental benefits of afforestation?
creates habitats
natural method
absorbs carbon
241
What are the economic benefits of afforestation?
relatively inexpensive
242
What are the social and economic disadvantages to river restoration?
expensive to construct and maintain
changes land use
small scale flooding occurs - inconvenience
243
What are the environmental benefits to river restoration?
recreates natural attractive fluvial environment
restores wetland
increases biodiversity
244
What counties surrounded the Jubilee River flood-relief channel?
Buckinghamshire
Oxfordshire
Berkshire
245
Which direction does the Jubilee River flow?
West
246
What is the source of the Jubilee River?
River Thames
247
What towns does the Jubilee River flow through?
Maidenhead
Eton
Old Windsor
Wraybury
248
What was the cost of the Jubilee River?
£110 million
249
What is the length of the Jubilee River?
11.7 km
250
What was the cost of repairing the channel after an episode of flooding?
£680,000
251
Which year was the Jubilee River completed?
2002
252
What is the width of the Jubilee River?
50m
253
Which year was the worst for flooding of the Thames since 1947?
2014
254
How many homes did the Jubilee River protect?
3,200 homes
255
What does the Jubilee River act as for the River Thames?
relief channel
256
Give an example of a flood management scheme in the UK
Jubilee River
257
What is the Jubilee River an example of?
flood relief channel
258
What type of engineering strategy is the Jubilee River?
hard engineering
259
What was the business insurance cost in 2014 for Wraysbury?
£500 million
260
What effect did the increase in insurance costs have on current insurance premiums?
increased the current insurance premiums
261
How many properties were protected in the affluent areas?
3,000 properties
262
What are the affluent areas surrounding the Jubilee River?
Eton
Windsor
263
How many properties were protected in less affluent areas surrounding the Jubilee River?
less than 3,000 properties
264
What does the Thames now experience due to the merging of the channels upstream?
higher discharge
265
What causes the Thames to experience higher discharge?
merging of channels upstream
266
What problem did the merging of the channels upstream lead to?
extreme floods in 2014
267
List the socioeconomic disadvantages of the Jubilee River
- insurance costs
- affluent properties
- flood relief
268
List the environmental disadvantages of the Jubilee River
- higher discharge
- algae
- eyesore
269
Why are the weirs of the Jubilee River an eyesore?
ugly- under normal flow conditions
270
Why does algae collect behind the weirs of the Jubilee River?
flow of water is stopped / slowed
