PAPER 1 - Physical Landscapes In The UK Flashcards

Question

What are the erosional landforms on coasts?

Answer 1

Headlands & bays Wave cut platforms Caves, arches, stacks, & stumps

Answer 2

The coastline is made up of bands of hard and soft rock Differential erosion creates the bay and headlands The soft rock is eroded by • hydraulic action • abrasion • solution The hard rock erodes at a slower rate, leaving a headland The soft rock erodes at a faster rate, leaving a bay

Answer 3

Waves attack the bottom of the cliff through erosional processes • hydraulic action • abrasion • solution This creates a wave cut notch at the base of the cliff Due to weathering processes (e.g. freeze thaw weathering) and gravity the overhang collapses Over time this process repeats, leaving a wave cut platform

Answer 4

The waves attack the cliff and create a crack through erosional processes • hydraulic action • abrasion • solution This leads to the crack becoming a cave and then eventually an arch (e.g. durble door) Overtime gravity and weathering cause the arch to collapse, leaving a stack (e.g. old harry) This collapses into a stump

Answer 5

Spit Bar Beach

Answer 6

Long shore drift When the sediment reaches an estuary (where a river meets the sea) the wind direction changes This creates a recurred end/hook Over time the sheltered water behind the spot creates a salt marsh (e.g. sandbanks Dorset)

Answer 7

Long shore drift The sediment continues to move across the bay leaving a lagoon behind it (e.g. slapton bay)

Answer 8

Sandy beaches are often found in sheltered bays with low energy waves Wave refraction = when waves enter these bays they tend to bend to mirror the shape of the coast As waves approach a coast they are retracted so that their energy is concentrated around headlands but reduced around bays

Answer 9

Hard engineering = using artificial structures to control natural processes • Groynes • Sea walls • Rock armour • Gabions

Answer 10

***Timber or rock structures built out to sea from the coast, which trap sediment and builds up the beach.*** *They stop longshore drift & The widened beach acts as a buffer to reduce wave damage.* **Cost:** timber groyns £150,000 (at every 200m) **Advantages:** • less expensive than other methods • a wider beach can be popular with tourists • useful structure for fishing **Disadvantages:** • interrupting longshore drift starves beaches further along the coast, often leading to more erosion elsewhere • unnatural and can be unattractive

Answer 11

***Concrete barrier often with a curved face, which reflects the energy of the waves back into the sea.*** **Cost:** £5000 - £10,000 **Advantages:** • effective at stopping the sea • often has a walkway/promenade for people to walk along **Disadvantages:** • can look obtrusive & unnatural • very expensive & high maintenance costs

Answer 12

***Large boulders at the foot of a cliff, which force waves to break, absorbing the waves energy.*** **Cost:** £200,000 per 100m **Advantages:** • relatively cheap & easy to maintain • often used for fishing • provide interest to the coast **Disadvantages:** • rocks from abroad or other parts of coastline = expensive to transport • often do not fit local geology • can be obtrusive

Answer 13

***Wire cages filled with rocks that support a cliff & provide a buffer against the sea.*** **Cost:** up to £50,000 per 100m **Advantages:** • cheap to produce & flexible in final design • can improve drainage of cliffs • can eventually become vegetated & merge into the landscape **Disadvantages:** • looks unattractive for a while • cages last 5-10 years before they rust

Answer 14

Soft engineering = less intrusive, more environmentally friendly methods that work with natural processes to protect the coast • Beach nourishment • Dune regeneration • Dune fencing

Answer 15

***Adding sand or shingle to a beach to make it higher or wider, so more wave energy is taken before they hit the cliffs.*** *The sediment is transported onshore by barge.* **Cost:** up to £500,000 per 100m **Advantages:** • blends in with existing beach (as sediment is usually obtained offshore locally) • bigger beach increases tourist potential **Disadvantages:** • needs constant maintenance unless structures are built to retain the beach • expensive

Answer 16

***Marram grass is planted on beaches to stabilise and develop sand dunes, which are natural buffers to the sea.*** **Cost:** £200 - £2000 per 100m **Advantages:** • maintains a natural coastal environment that is popular with people & wildlife • relatively cheap **Disadvantages:** • time consuming to plant • people may not respond well to being restricted from planted areas • can be damaged by storms

Answer 17

***Fences act as a barrier to protect the sand dunes, which naturally stop erosion.*** **Cost:** £400 - £2000 per 1000m **Advantages:** • minimal impact on natural systems • can control public access to protect other ecosystems **Disadvantages:** • look unsightly especially if fences break • regular maintenance needed especially after storms

Answer 18

Enables the controlled retreat of the coastline and involves allowing the sea to flood over low lying & (economically) low value land.

Answer 19

Medmerry managed retreat: • created a large natural salt marsh to form a natural buffer to the sea • help to protect the surrounding Farmland and caravan parks from flooding • establish a valuable wildlife habitat and encourage visitors to the area

Answer 20

Small coastal town on the south coast of England Popular tourist destination - (Population increases from 4000 to 15,000 in the summer) In the world heritage site - Jurassic coast Famous for its fossils • Built on unstable cliffs • Powerful waves from the south west - fastest eroding coastline in Europe • Many properties destroyed/damaged • Sea walls have been breached many times

Answer 21

**The Lyme Regis environmental improvement scheme:** Set up by west Dorset district council in 1990s Aimed to provide long term coastal protection and reduce threat of landslips Engineering works completed in 2015 Consultation meeting before and during construction work & public kept informed - To reduce conflicts between different interest groups (e.g. property owners, fishermen, & environmentalists)

Answer 22

**Positive outcomes:** • new beaches have increased visitor numbers & seafront business are thriving • new defences have stood up to recent stormy winters • the harbour is now better protected, benefiting boat owners & fisherman

Answer 23

**Negative outcomes:** • increased visitor numbers have led to conflicts with local people who think traffic congestion & litter has increased • some people think the new defences have spoilt the natural coastal landscape • the sea wall may interfere with coastal processes & affect neighbouring stretches of coastline, causing conflicts elsewhere • stabilising cliffs will prevent landslips that may reveal important fossils - a potential conflict

Answer 24

Drainage basin = an area of land drained by a river and its tributes Source = the start of a river Tributary = a small stream that joins a larger river Confluence = where a tributary joins a larger river Water head = the edge of a river basin Mouth = the end of a river - usually where it meets the sea

Answer 25

**Upper course:** • steep gradient **Middle course:** • gentle gradient **Lower course:** • very gentle gradient

Answer 26

**Upper course:** • steep sided valley (v-shaped) • thin channel • waterfalls & gorges • vertical erosion **Middle course:** • valley floor developing • wider river channel • meanders • lateral erosion **Lower course:** • wide flood plains • deep & wide river channel • banded by levees • lateral erosion

Answer 27

Lateral erosion = occurs on the outside bend of a river; the river erodes the banks & migrated sideways, carving out a wider & flatter valley floor. Vertical erosion = downwards erosion creating a steep valley

Answer 28

When velocity & gradient of the river decreases, it looses energy so it deposits the material

Answer 29

The total amount of load a river carries depends on its velocity. After a rainstorm, rivers often look muddy because they are flowing fast; they are transporting a large amount of sediment. Most of the load is deposited at the mouth of the river

Answer 30

**Large boulders:** • Transported by traction during periods of very high flow • Deposited at the upper course **Finer sediment:** • Transported by being held in suspension • Deposited further downstream on river beds/banks

Answer 31

**Upper course:** • interlocking spurs • waterfalls • gorges **Middle & lower course:** • meanders • ox-bow lakes • flood plains • levees • estuaries

Answer 32

**Interlocking spurs** = areas of hard rock which jut out into the valley. • Vertical erosion happens more than lateral erosion, creating a v-shaped valley.

Answer 33

• The river flows over hard, more resistant rock which erodes very slowly. • Underneath is softer, less resistant rock which erodes at a faster rate, undercutting the hard rock, creating an overhang. • A plunge pool which further undercuts the hard rock is created by hydraulic action through the power of the water & by abrasion through the sand paper effect of the material. • Eventually the overhang of hard rock collapses.

Answer 34

**Gorge** = a narrow steep sided valley that is usually found immediately downstream of a waterfall. • Over hundreds or even thousands of years, the gradual retreat of a waterfall forms a gorge.

Answer 35

Thalweg = the line of fastest flow (where the river is flowing fastest) **Meander** = a bend in a river. • Over shallow areas, water flows slowly in the river bed. Over deep areas, water flows faster. • This eventually sets in motion a helicoidal flow (which is a corkscrew movement) across from one bank to another. • Fast flowing water on the outside bank causes lateral erosion through abrasion & hydraulic action which undercuts the bank & forms a river cliff. • Helicoidal flow continues. • Sand and pebbles deposit on the inside bend where it is slower and has less energy resulting in slip off slope.

Answer 36

• Over time, as meanders migrate across the valley floor, they may start to erode (through hydraulic action & abrasion) towards each other. • Gradually the neck of the meander narrows until it is completely broken through (often during a flood), to form a new straighter channel. • The old meander loop is cut off by deposition to form an ox-bow lake.

Answer 37

**Flood plain** = a wide, flat area of marshy land on either side of a river • They are made of alluvium (silt) deposited by a river when it floods. Floodplains are used for farming as the soils are very fertile.

Answer 38

Silt deposits on flood plain During a flood: heavier coarser sediment builds up around river banks & the finer particles of sediment are carried further, creating natural levees. River bed deposits. After many floods: the levees get higher with every flood & more deposits build up the bed, increasing the river level which means more flooding.

Answer 39

**Estuary** = the tidal part of a river where the channel widens as it reaches the sea. • A large river enters the sea at a narrow mouth. • After the ice age, melting ice caused sea levels to rise flooding low-lying valley sides. • The original river channel is now on the estuary floor. - high tidal range - very wide - mudflats

Answer 40

**Mudflats** = built up layers of mud, which are exposed at low tide but covered at high tide. In sheltered areas water velocity is reduced causing deposition. The layers of mud build up, forming a mudflat.

Answer 41

**Flooding** = a river flood happens when a river channel can no longer hold the amount of water flowing in it. • **Precipitation** • **Geology (rock types)** • **Relief (shape of the land)** • **Land use** - **urbanisation** - **deforestation** - **agriculture**

Answer 42

Torrential rainfall can lead to flash floods as river channels can’t contain the amount of water flowing in them. Steady rainfall over several days can also have the same effect.

Answer 43

Impermeable rocks do not allow water to pass through them, causing water to flow overland and into the river, speeding up water flow which makes flooding more likely. Permeable rocks allow water to pass through so risk of flooding is reduced.

Answer 44

Steep slopes encourage the fast movement of water from high up down into river channels below. This increases the risk of flooding. In flatter areas where water is transferred into river channels at a slower rate.

Answer 45

**Urbanisation:** Building on floodplains creates more impermeable surfaces so when it rains water is transferred further into river channels, increasing the risk of flooding. **Deforestation:** Trees capture rainfall and store it temporarily or it is evaporated before it falls on the ground slowing the transfer into rivers. When trees are removed water flows quickly into rivers. **Agriculture:** Soils are left bare with no trees or plants to capture the water, leading to rapid transfer of rainfall into rivers.

Answer 46

**Lag time** = time between peak rainfall & peak discharge. - **longer** lag time means **less** chance of flooding. - **shorter** lag time means **more** chance of flooding. **Base flow** = water flowing underground. **Rising limb** = when the amount of water in the river is increasing. **Falling limb** = when the amount of water in the river is decreasing.

Answer 47

**Rock type:** • **shorter lag time** = impermeable rocks encourage rapid overflow • **longer lag time** = permeable rocks encourage a slow transfer by groundwater flow **Land use:** • **shorter lag time** = urbanisation encourages rapid water transfer • **longer lag time** = forests slow down water transfer becuase of interception **Relief:** • **shorter lag time** = steep slopes lead to rapid water transfer • **longer lag time** = gentle slopes slow down transfer **Basin size:** • **shorter lag time** = small basins often Lead to rapid water transfer • **longer lag time** = large basins result in a relatively slow water transfer

Answer 48

**Hard engineering:** • dams & reservoirs • channel straightening • embankments • flood relief channels **Soft engineering:** • flood plain zoning • flood warning & preparation • planting trees • river restoration

Answer 49

**Dams & reservoirs** = large concrete barriers across a river to stops its flow. **Advantages:** • provide drinking water • provide hydroelectric power **Disadvantages:** • expensive • flood local areas • stop fish migration • break up communities

Answer 50

**Channel straightening** = when a meandering section of a river is straightened to improve water flow. **Advantages:** • flood risk reduced • insurance costs decrease • people are happier & safer **Disadvantages:** • expensive • increases flooding downstream

Answer 51

**Embankments** = artificially raised river banks to contain more water. **Advantages:** • cheaper than other methods • provide walking routes & habitats **Disadvantages:** • prevent fishing • need constant maintenance (expensive)

Answer 52

**Flood relief channels** = artificially made channel to carry more water. **Advantages:** • Exeter’s relief channel protects 3000 homes • insurance costs reduced • provide footpaths & cycle paths **Disadvantages:** • expensive • force people to move • look ugly • can destroy habitats

Answer 53

**Flood plain zoning** = not building close to a river. **Advantages:** • reduces flood risk • low cost • increases green space in urban areas **Disadvantages:** • many cities are already built on floodplains • housing shortage in uk • habitats are destroyed to build on other greenfield sites

Answer 54

**Flood warning & preparation** **Advantages:** • very cheap • increases people’s safety • give people time to save money/ protect their valuables **Disadvantages:** • not everyone listens to • insurance costs increase

Answer 55

**Planting trees** **Advantages:** • creates habits • increases biodiversity • takes in CO2 (reduces climate change) • inexpensive **Disadvantages:** • not always aesthetically pleasing • lose grazing land for farming

Answer 56

**River restoration** = rivers that have been previously engineered are put back to their natural state. **Advantages:** • creates habits • increases biodiversity • reduces flood risk down stream (protects houses) • aesthetically pleasing (improves tourism) **Disadvantages:** • possible loss of farmland • can be expensive • not always possible for every river

Answer 57

• long history of severe flooding • 1998 flooding - closure of railways station & local roads - over 150 homes & businesses affected • similar flooding in 2007

Answer 58

• completed in 2012 • cost around £18.5 million • earth embankment built parallel to M40 to create a flood storage area - collects rainwater that would otherwise cause the river Cherwell to flood = protects property - 2.9km long & 4.5m high - capable of holding 3 million cubic meters of water • raising the A361 • new pumping station to transfer rainwater into the river below Banbury • biodiversity action plan set up to create habitats & ponds and trees to absorb and store excess water • 441 houses & 73 commercial properties protected = saving 100 million in damages