Section C: Physical landscapes in the UK

what is a landscape

an area's character that comes from the actions and interactions of natural and human elements

what does the character of a landscape depend on

-initial geology= this geology shapes the landscape’s relief, which then attracts human action and interaction

in the Uk, where are the uplands mostly found

The uplands are mainly in the north and west of the country, including Northern Ireland, Scotland, Wales, and northern England, such as the Lake District, Grampian Mountains, and Snowdonia

where are the lowland areas found in the UK

The lowlands lie in the south and east of the UK, including central and southern England, such as the Cotswolds, Norfolk, and South Downs

where do many cities sit

• Many cities sit in lowland areas and often along major river routes, like Liverpool on the Mersey, Bristol on the Severn estuary, and the River Avon

Which one of these terms would you be more likely to use for an upland landscape than a lowland one? 

[1 mark]

	A	Undulating
	B	Rugged
	C	Fertile
	D	Gentle

B

what is the coast

The meeting point between land and sea

what are the two parts that coastal processes are divided into

• Marine processes: offshore (water-based)

• Terrestrial processes: onshore (land-based)

what are waves

• Waves are marine processes that

  • erode

  • transport

  • deposit

how are waves formed

are formed as winds blow over the surface of the sea

what are the 3 factors that the height and strength of the wave is dependent on

-the fetch

-the amount of time the wind blows

-the strength of the wind

when will the wave be the largest

the greater the strength, time and fetch of the wind the larger the wave

what happens when the wave enters the shallow water of the coast

as a wave enters shallow water of the coast, friction from the seabed causes the wave to lean forward and eventually crest and break onto the beach

-swash

-backwash

the movement of water up the beach

-the return movement

2 types of waves

-destructive waves erode the beach

-constructive waves are beach builders

constructive waves

-strong swash

-weak backwash

-wavelength is long with a low height

-low frequency

-forms depositional sandy beaches

destructive waves

-weak swash

-strong backwash

-short wavelength with high height

-high frequency

-forms erosional shingle beaches

Identify which statement below best describes the characteristics of a destructive wave?

	A	long wavelength and weak backwash
	B	short wavelength and weak backwash
	C	short wavelength and strong backwash
	D	long wavelength and strong backwash

[1 mark]

• The answer is C [1]:

  • A destructive wave has a short wavelength, high frequency rate, steep wave gradient and a strong backwash 

what does weathering mean

The break-down of rock in-situ ( in the original place)

what is the difference between weathering and erosion

weathering does not involve the movement of the material

sub-aerial weathering

describes coastal processes that are not linked to the action of the sea and includes freeze-thaw weathering and chemical weathering

what does weathering do to cliffs

weakens cliffs and makes them more vulnerable to erosion

freeze-thaw weathering

-water enters cracks in the rocks

-when temp drops to 0 or below, the water in the crack freezes forming ice

-water expands as it freezes creating huge forces on the surrounding areas of the rock

-these acting forces makes the cracks in the rock bigger

-when the temp rises again, the frozen water thaws

-this cycle of freezing and thawing occurs many time, until eventually a fragment of the rock breaks away completely

chemical weathering

When a chemical process breaks down rocks,

example of chemical weathering

rainwater will absorb co2 from atmosphere making it slightly acidic

this will interact with minerals in the rock and forms new material

biological weathering

when living things wear away rocks

example of biological weathering

-trees and other plants grow in the cracks of a rock formaton

-the root grow bigger and push open cracks in the rocks making them wider and deeper

-the growing tree forces the rock apart over time

• Burrowing animals like rabbits disturb the ground above their burrows

• This disturbance puts pressure on cracks, causing pieces of rock to fall off

what is mass movement

The downhill movement of material under the influence of gravity

slump

-typically located on weaker rock types that get saturated and heavy

-often occurs at the coast and is called rotational slip

-a large area of land moves down the slope in one piece

-it slumps and leaves a curved indented surface

fall

-slope rise sharply and movement happens quickly

• Several reasons caused this.

  • Extreme weathering: Freeze-thaw action loosens rocks, making them unstable and causing collapse

  • Excess rain will soften the surface and cause the slope to collapse

  • Earthquakes dislodge unstable rocks

  • Hot weather dries out soil, causing it to shrink and rocks to fall

slide

• A mass of material moves together until it reaches the bottom of a slope

Worked Example

Outline two ways that sub-aerial processes can affect the shape of a cliff

[4 marks] 

1. Freeze-thaw weathering occurs when temperatures rise above and fall below freezing at 0°C. Water trapped in cracks of a rock freezes and expands, putting pressure on the crack. As temperatures rise, water melts, pressure releases, and the crack contracts. Repeated cycles break the rock apart over time. [U] More freeze-thaw happens in winter than in summer, leading to more weathering of the cliff face, making the cliff weaker. [K]

2. With chemical weathering, the rock type determines how quickly the rock dissolves. Rainwater and seawater are slightly acidic. Limestone reacts with the acid in water faster than granite because it is less resistant. [U] A cliff made of softer, less resistant limestone rock will weather faster and become more unstable faster than a cliff made of harder, more resistant granite rock. [K]

Marking guidance

• Provide the main characteristics that explain briefly how each weathering process affects the shape of a cliff.

Mark allocation

• This is a 'level of response' answer. Each point made in the answer does not equal a mark. 

• 2  marks for knowledge [U]  of a sub-aerial process.

2  marks for applying [Ap] that knowledge to determine the effects on a cliff.

Alternative content

• The answer above is just one example of a response to this question. Other information that could be used in the answer includes:

  • Biological weathering

what is responsible for most of the erosion that happens along a coast

• Destructive waves are responsible for the majority of erosion that happens along a coast

4 types of erosion

-hydraulic power/action

-attrition

-abrasion

-solution

hydraulic action

the sheer force of the waves hitting the coast

attrition

materials are carried by the waves and bump against each other and are worn smaller and smoother -forms shingles and sand and doesn't really erode the coast

solution

water which is slightly acidic dissolves the rock

what are some sources where materials in the sea arrive from

• Eroded from cliffs

• Transported by longshore drift along the coastline

• Brought inland from offshore by constructive waves

• Carried to the coastline by a river

once in the water, what are the 4 ways in which the material is moved

-traction

-saltation

-suspension

-solution

traction

is where large heavy material is dragged along the sea floor

saltation

is where smaller materials is bounced across the sea floor

suspension

is where fine materials is held in the water

solution

is dissolved material carried in the water

Longshore drift

• This is the main process of deposition and transportation along the coast 

• Waves approach the beach at an angle due to the prevailing wind

• As the waves break, the swash carries material up the beach at the same angle

• As the swash dies away, the backwash carries the material down the beach at right angles (90°) 

• The process repeats, transporting material along the beach in a zig-zag movement

Worked Example

Describe and explain the process of longshore drift

[4 marks] 

• Longshore drift is the process where the waves transport material, [K] such as sand, along the beach in the direction of the prevailing wind. [K] The swash moves material up the beach at an angle as the waves approach in a similar direction to the wind. [U] The material backwashes down the beach at 90° due to gravity. This movement continues along the beach in a zigzag motion. U] 

Marking guidance

• Your focus is 'longshore drift'—what is it and how does it work?

Mark allocation

• This is a 'level of response' answer. Each point made in the answer does not equal a mark. 

•  2 marks for knowledge. [K]  

•  2 marks for understanding. [U]

The command is describe and explain and answers should identify longshore drift as the method of transporting material along a beach and explain how that happens

Deposition

• Deposition occurs when material is dropped from seawater

• This happens when the water flow's speed (velocity) decreases

• This means the force is no longer strong enough to keep the material suspended in the water, so it drops to the ground

where does sediment deposits

in bays to form beaches

where do salt marshes and mudflats form

in sheltered estuaries typically behind spits

Worked Example

Study Figure 9, a photograph taken along the stretch of coastline.

Suggest one type of mass movement that is affecting these cliffs.

[1 mark]

Answer: 

• Rock fall [1 mark]

Marking guidance

The question asks about mass movement and not weathering; therefore, your answer should reflect this.

Alternative content

• The answer above is just one example of a response to this question. Other information that could be used in the answer includes:

  • Slumping

  • Landslip

  • Landslide

erosion of softer rocks like sand and clays along a coastline

erode easily due to destructive waves, creating low flat landscape like bays and beaches

erosion of harder rock

coastline with harder rock erode slowly and create rugged landscapes like headlands

how does hard rock affect the coastline

shape of the cliff= usually high and steep

cliff face= has bare rock and rugged outcrops

foot of cliff= has boulders and rocks at the base

how does soft rock affect the coastline

shape of cliff= cliff face is lower and less steep

cliff face=is smoother with evidence of slumping

foot of cliff=there are few rocks at the base and usually there is some sand and mud

how do headland and bays form

• These happen where hard and soft rocks alternate and run perpendicular to incoming waves

• The softer rock, like clay, erodes backward and forms an inlet

• The inlet erodes and curves inwards, forming a bay, often with a beach

• More resistant rock, such as granite, sticks out into the sea as a headland

characteristics of a headland

• Projects out to sea

• Is longer than it is wide

• Has a geology of resistant rock

• Cliffs lining its sides

characteristics of a bay

• A wide, open entrance from the sea

• A roughly semi-circular shape that extends into the coastline

• Land that is lower than the headlands surrounding it

• A bay may or may not have a beach

cliffs

• Cliffs are shaped through erosion and weathering processes

• Soft rock erodes quickly and will form sloping cliff faces

• Steep cliffs are formed where there is hard rock facing the sea

wave cut platforms

• These are wide, gently sloped surfaces found at the foot of a cliff

  • The sea hits the base of a cliff between the high and low water mark, forming a wave-cut notch

  • Abrasion, corrosion, and hydraulic action push the notch deeper into the cliff

  • The cliff becomes unstable and collapses when it is undercut

  • The waves wash away the eroded material, creating a wave-cut platform

  • The process repeats, and coastal retreat occurs as the cliff keeps moving backwards

how are caves formed

-waves slow down as they reach the shore and move along the sea floor

-the angle of the waves changes and turns making the crest parallel to the coast. this is called wave refraction

-this refraction focuses erosion on every side of the headland

-hydraulic power, abrasion and some corrosion start attack weaknesses in the headland

-the crack widens and abrasion wears away at the forming cave

how are arches formed

continued wave action means that the cave grows larger and eventually breaks through the headland to form an arch

how are stacks formed

the base of the arch gets wider and thinner due to erosion below and weathering from above. the roof of the arch collapses, leaving an isolated column of rock called a stack

how are stumps formed

wave action and weathering undercut the base of the stack until it collapses leaving a stump

how are beaches formed

-Form in sheltered areas such as bays through deposition via constructive wave movement, where the swash is stronger than the backwash

-When a constructive wave carries sediment up the beach, the largest material is deposited along the upper reach of the swash

-As the backwash moves back down the beach, it loses water and therefore energy as it travels due to the porosity of the sand

-Consequently, the deposition of sediment gets progressively smaller, and the beach is therefore sorted by wave deposition, with the smallest mud particles settling in the low-energy environment offshore

-If a destructive wave forms due to a storm, then large shingle is thrown above the usual high tide level to form a ridge at the top of the beach called a berm

sand dunes

-Blown sand can create sand dunes at the backshore of a beach

what type of environment are sand dunes

dynamic means that ever changing and does not stay the same

where do sandy beaches usually have sand dunes

Sandy beaches usually have sand dunes at their rear because of strong onshore winds transporting dried, exposed sand

how are embryo dunes formed

• Sand grains are trapped and deposited against any obstacle (rubbish, rocks, driftwood, etc.) and begin to form embryo dunes

sand dune formation

The wind blows deposited sand up the beach. Objects like wood, driftwood or human rubbish can block the wind, leading to hills of sand. The hills of sand can allow plants and vegetation to grow.

• An obstruction deposits windblown sand against it. Pebble or driftwood

• As more sand particles are caught, the dunes grow in size, forming rows at right angles to the prevailing wind

• Over time, the ridges of the dunes will be colonized and fixed by vegetation in a process called succession

• The first plants, known as pioneer species, must cope with the following challenges:

  • Salinity

  • Lack of moisture as sand drains quickly (highly permeable)

  • Wind

  • Temporary submergence by wind-blown sand

  • Rising sea levels

embryo dunes

• Wind-blown dried sand is trapped by debris and deposition begins

• Pioneer species such as Lyme Grass and Sea Couch Grass begin to colonise

• There is little soil content and high pH levels (alkaline)

• Embryo dunes are very fragile and reach a maximum height of 1 metre

fore dunes

• The embryo dunes bring some protection against the prevailing wind

• This allows other species of plant to grow, such as Marram Grass

• Marram grass begins to stabilise the dune with its root system

• These plants add organic matter to the dunes, making the dunes more hospitable for plants that later grow

• A microclimate forms in the dune slack

• Maximum height is 5 metres

yellow dunes

• These are initially yellow but darken as organic material adds humus to the soil

• Marram grass still dominates the vegetation, but more delicate flowering plants and insects are found in the dune slacks

• 20% of the dune is exposed, down from 80% 

• Height does not exceed 8 metres

grey dunes

• 
  Grey dunes are more stable, with less than 10% of exposed sand and have a good range of biodiversity

• Soil acidity and water content increase as more humus is added

• Shrubs and bushes begin to appear

• Height is between 8 and 10 metres

mature dunes

• As the name suggests, these are the oldest and most stable of the dunes

• They are found several hundred metres or more from the shoreline

• The soil can support a variety of flora and fauna, such as oak trees and alders (climax vegetation)

• This is the final stage in succession, which is known as the climax community stage

what are spits

• An extended stretch of sand or shingle that extends out to sea from the shore

• Spits occur when there is a change in the shape of the coastline

• Or the mouth of a river, which prevents a spit forming across the estuary

• A spit may or may not have a 'hooked' end, depending on opposing winds and currents

stages of formation of a spit

• Sediment is transported by the action of longshore drift

• Where the coastline changes direction, a shallow, sheltered area allows for deposition of sediment

• Due to increased friction, more deposition occurs 

• Eventually, a spit slowly builds up to sea level and extends in length

• If the wind changes direction, then the wave pattern alters and results in a hooked end

• The area behind the spit becomes sheltered

• Silts are deposited here to form salt marshes or mud flats

• 

bars

• When a spit grows across a bay and joins two headlands together

• A bar of sand is formed (sandbar)

• Sandbars can also form offshore due to the action of breaking waves from a beach

• 
  

  

Worked Example

Figures 3.1, 3.2, and 3.3 show three coastlines.

Identify each of the following landforms:

 (i)

landform W in Fig. 3.1

[1 mark]

(ii)

landform X in Fig. 3.2

[1 mark]

(iii)

landform Y in Fig. 3.2

[1 mark]

(iv)

landform Z in Fig. 3.3.

[1 mark]

Answer:

• W - Wave-cut platform [1]

• X – Beach [1]

• Y – Sand dunes [1]

• Z - Cliff [1]

what has the geology of the Dorset coast perfect for

• The geology of the Dorset coast is perfect for both erosional and depositional landforms

• It has bands of soft clay and harder limestone and chalk

• These rocks erode at different rates, creating headlands, bays, arches, a long tombolo and more

Durdle Door

• 
  Durdle Door is an example of an arch formation

  • Wave erosion opened a crack in the tough limestone headland

  • Further erosion led to a cave which developed into an arch in the headland

  • Softer rocks behind the limestone have been washed away, leaving an eroding line of chalk cliffs

Lulworth Cove

• Lulworth Cove is a small bay that was formed when a gap was eroded in the band of tough limestone 

  • Lying behind this limestone is a band of soft clay, and this has been scooped out (eroded away) to form a bay 

  • The entrance to the cove is narrow because the harder band of limestone is more resistant to erosion

Swanage

• Swanage sits on two beach bays called Studland Bay and Swanage Bay

  • These are areas of soft sandstone and clay

  • Between the two bays is The Foreland, a headland of harder chalk

Old Harry

• 
  Old Harry and his wife sit at the end of The Foreland

  • The chalk headland has eroded to form caves, arches and a stack (Old Harry)

  • Further erosion has resulted in a stump called Old Harry's Wife

Chisel beach

• Chesil Beach is an 18-mile-long pebble tombolo 

  • Formed through the process of longshore drift, it joins the Isle of Portland to the mainland

  • There is a shallow lagoon behind the tombolo called The Fleet Lagoon

coastal management

• Coastal management aims to protect the environment and people from erosion and flooding

why can some coastal areas cannot get protection

• Coastal management aims to protect the environment and people from erosion and flooding

hard engineering methods

• ard engineering builds sea defences using materials like concrete, wood, or rock

• Construction is expensive, and they need regular maintenance

• Defences protect against the waves' power

• Every type of defence has strengths and weaknesses, such as:

  • Protecting one area can affect other regions along the coast, leading to increased erosion and flooding

• Hard engineering is used when settlements and expensive installations, like power stations, are at risk because the economic benefit exceeds the costs of construction

what are examples of hard engineering defences

• sea walls, rock armour, gabions and groynes

sea wall

• These are usually built from concrete and curved outward to reflect the waves' power back out to sea

advantage of sea wall

Advantages

• Most effective at preventing both erosion and flooding (if the wall is high enough)

disadvantage of sea wall

Disadvantages

• Very expensive to build and maintain

• It can be damaged if the material in front of the wall is not maintained

• It can restrict access to the beach

• Unsightly to look at

groynes

• Wood, rock or steel piling built at right angles to the shore, which traps beach material being moved by longshore drift

advantage of groynes

Advantages

• Slows down beach erosion

• Creates wider beaches

disadvantages of groynes

Disadvantages

• Beaches along the coast are deprived of sand

• Wooden groynes need to be maintained to prevent wood rot

• Walking along the shoreline is difficult

Off-shore barriers

• Large concrete blocks, rocks and boulders are sunk offshore to alter wave direction and dissipate wave energy

Advantages of off-shore barriers

• Effective at breaking wave energy before reaching the shore

• Beach material is built up

• Low maintenance

• Maintains natural beach appearance

disadvantages of off-shore

• Expensive to build

• Can be removed in heavy storms

• Can be unattractive

• Prevents surfing and sailing

Rip-rap or rock armour

• Large boulders are piled up to protect a stretch of coast

advantages of rip-rap

• Cheaper method of construction

• Works to absorb wave energy from the base of cliffs and sea walls

disadvantage of rip-rap

• Boulders can be eroded or dislodged during heavy storms

gabions

• A wall of wire cages filled with stone, concrete, sand, etc., built at the foot of cliffs