Physical Landscapes in the UK (Coasts and Rivers)

What is a landscape?

An area whose physical features give it a particular appearance.

Where are most of the UK's major upland areas?

Mainly in the north + west of the UK.

Where are most of the UK's major lowland areas?

Mainly in the south + east of the UK.

What are examples of major UK upland areas?

Scottish Highlands, Grampian Mountains, Pennines, Lake District + mountains of Wales.

What are examples of major UK lowland areas?

The Fens, London Basin + lowlands of southern/eastern England.

What are examples of major UK river systems?

Severn, Thames, Trent, Mersey + Ouse.

What is a wave?

Movement of energy through water, usually generated by wind.

What factors affect wave energy?

Wind strength, how long the wind blows + fetch.

What is fetch?

The distance wind blows across open water.

What are constructive waves?

Low-energy waves with strong swash + weak backwash that build beaches.

What are destructive waves?

High-energy waves with weak swash + strong backwash that erode beaches.

What is swash?

Movement of water up a beach after a wave breaks.

What is backwash?

Movement of water back down a beach towards the sea.

What are the characteristics of constructive waves?

Low frequency, low height, long wavelength, strong swash + weak backwash.

What are the characteristics of destructive waves?

High frequency, steep/high waves, short wavelength, weak swash + strong backwash.

Why do constructive waves cause deposition?

Strong swash carries more sediment up the beach than weak backwash removes.

Why do destructive waves cause erosion?

Strong backwash removes more beach material than the weak swash deposits.

What is weathering?

The breakdown of rock in situ without it being moved.

What does in situ mean?

In its original place.

What are the three main types of weathering?

Mechanical, chemical + biological.

What is mechanical weathering?

The physical breakdown of rock without changing its chemical composition.

How does freeze-thaw weathering work?

Water enters cracks - freezes + expands - widens cracks - repeated cycles eventually break rock apart.

What is chemical weathering?

The breakdown of rock through chemical reactions.

How can carbonation weather limestone?

Rainwater absorbs CO2 forming weak carbonic acid - this reacts with/dissolves limestone.

What is biological weathering?

The breakdown of rock by living organisms.

How can plant roots cause biological weathering?

Roots grow into cracks + widen them as they grow.

What is mass movement?

The downhill movement of weathered material under the force of gravity.

What is a rockfall?

Rock fragments break away + fall down a steep slope or cliff.

What is a landslide?

Rock or soil rapidly moves downhill along a slope.

What is rotational slumping?

Saturated material moves downhill along a curved slip plane.

Why can heavy rainfall increase mass movement?

Water adds weight + reduces friction, making slopes less stable.

What are the four main processes of coastal erosion?

Hydraulic action, abrasion, attrition + solution.

What is hydraulic action?

Waves force water + air into cracks - pressure weakens the rock until pieces break off.

What is abrasion?

Sediment carried by waves is thrown against the coast, wearing it away.

What is attrition?

Rocks carried by waves collide with each other - becoming smaller, smoother + rounder.

What is solution at the coast?

Soluble rock is dissolved by seawater.

What is coastal transportation?

The movement of sediment along the coastline.

What is longshore drift?

The movement of sediment along a coastline caused by waves approaching the beach at an angle.

How does longshore drift work?

Swash carries sediment up the beach at the wave angle - backwash moves straight down under gravity - repeated movement transports sediment along the coast.

What is deposition?

The dropping of material that was being transported.

When does coastal deposition occur?

When waves lose energy + can no longer carry their sediment.

What factors can affect coastal landscapes?

Rock type, geological structure + wave energy.

What is differential erosion?

Softer rock is eroded faster than more resistant rock.

How do headlands and bays form?

Alternating hard + soft rock are eroded at different rates - soft rock retreats to form bays while resistant rock remains as headlands.

Why are headlands often heavily eroded?

Wave refraction concentrates wave energy onto them.

Why are beaches often found in bays?

Wave energy is lower, encouraging deposition.

How does a cliff and wave-cut platform form?

Waves erode the cliff base - a wave-cut notch forms - overhang collapses - cliff retreats - repeated retreat leaves a wave-cut platform.

What is a wave-cut notch?

An indentation eroded into the base of a cliff by wave action.

What is a wave-cut platform?

A gently sloping rocky surface left behind as a cliff retreats.

How do caves, arches, stacks and stumps form?

Erosion enlarges a crack in a headland - cave - cave erodes through to form an arch - roof collapses leaving a stack - stack erodes/collapses leaving a stump.

What is a beach?

An accumulation of sand or shingle deposited along the coastline.

Where do beaches commonly form?

Where deposition exceeds erosion, often in sheltered bays.

What is a spit?

A narrow ridge of sand or shingle attached to land at one end + extending into the sea.

How does a spit form?

Longshore drift transports sediment - coastline changes direction or crosses an estuary - sediment continues into open water + is deposited.

Why can the end of a spit become recurved?

Changes in wind/wave direction can curve the end towards the land.

What may form behind a spit?

Sheltered water allows mudflats + salt marshes to develop.

What is a bar?

A ridge of deposited sediment extending across a bay, joining two headlands.

How does a bar form?

A spit continues growing across a bay until it connects with the opposite headland.

What can form behind a coastal bar?

A lagoon.

What are sand dunes?

Ridges or hills of wind-blown sand formed behind a beach.

How do sand dunes begin to form?

Wind transports dry sand inland - obstacles trap it - vegetation colonises + stabilises the accumulating sand.

What is coastal management?

Strategies used to reduce coastal erosion + flooding.

What is hard engineering?

Building artificial structures to control natural coastal processes.

What is soft engineering?

Working with natural processes to reduce erosion/flooding with less environmental disruption.

How does a sea wall protect the coast?

A strong wall reflects/absorbs wave energy + prevents erosion/flooding behind it.

What are advantages of sea walls?

Very effective + can protect valuable property/infrastructure for many years.

What are disadvantages of sea walls?

Expensive, visually intrusive + reflected waves can increase erosion at the base.

What is rock armour?

Large boulders placed at the coast to absorb wave energy.

What are advantages of rock armour?

Effective, relatively quick to construct + absorbs wave energy.

What are disadvantages of rock armour?

Can be expensive to transport, may look unnatural + can restrict access.

What are gabions?

Wire cages filled with rocks placed along the coast.

How do gabions protect the coast?

Rocks absorb wave energy + reduce erosion.

What are advantages of gabions?

Relatively cheap + quick to install.

What are disadvantages of gabions?

Wire cages can corrode/break + they may be unattractive.

What are groynes?

Barriers built at right angles to the coast that trap sediment moved by longshore drift.

How do groynes protect the coast?

They create a wider/higher beach which absorbs more wave energy.

What are advantages of groynes?

They build beaches, reduce erosion + can increase recreational value.

What are disadvantages of groynes?

They interrupt longshore drift, causing sediment starvation + increased erosion further down the coast.

What is beach nourishment?

Adding sand or shingle to a beach to replace material lost by erosion.

What is beach reprofiling?

Redistributing beach sediment to create a shape that absorbs wave energy more effectively.

What are advantages of beach nourishment/reprofiling?

They look natural, maintain a beach + absorb wave energy.

What are disadvantages of beach nourishment/reprofiling?

They require repeated maintenance + can become expensive over time.

What is dune regeneration?

Restoring/stabilising sand dunes using vegetation, fencing or controlled access.

How does dune regeneration protect the coast?

Dunes act as a natural barrier that absorbs wave energy + reduces flooding.

What are disadvantages of dune regeneration?

It can restrict access + dunes may still be damaged by storms or people.

What is managed retreat?

Allowing selected low-value coastal land to flood or erode naturally.

What are advantages of managed retreat?

Relatively low cost + can create natural habitats such as salt marshes that absorb wave energy.

What are disadvantages of managed retreat?

Land/property may be lost + compensation or relocation may be needed.

Why must coastal management strategies be evaluated?

A strategy's economic, social + environmental costs must be compared with its benefits.

What is a river's source?

The point where a river begins, usually in an upland area.

What is a river's mouth?

The point where a river enters the sea, lake or another river.

What is a tributary?

A smaller river or stream that flows into a larger river.

What is a confluence?

The point where two rivers meet.

What is a drainage basin?

The area of land drained by a river + its tributaries.

What is a watershed?

The boundary separating one drainage basin from another.

What is a river's long profile?

The change in the gradient of a river from its source to its mouth.

How does a river's long profile change downstream?

It becomes progressively less steep towards the mouth.

What is a river's cross profile?

The shape of the river channel + valley when viewed across it.

How does a river valley change downstream?

It generally becomes wider, flatter + less steep-sided.

How does the river channel change downstream?

It generally becomes wider + deeper.