Edexcel Igcse Geography. Coastal Environments Key Words

Front 1

Sub-aerial processes

Back 1

The general re-shaping of the land by normal atmospheric processes, for example wind and rain; includes weathering, mass movement, erosion and deposition.

Front 2

Longshore drift

Back 2

The movement of loose materials along a coastline by wave action because waves break at an oblique angle to the shore.

Front 3

Ecosystem

Back 3

An organic community of plants and animals interacting with their environment

Front 4

Coral reef

Back 4

A marine ecosystem formed by reef-building corals

Front 5

Mangroves

Back 5

Tropical and sub-tropical coastal forests; mangrove trees can grow in salty, tidal water.

Front 6

Sand dunes

Back 6

Coastal sand hills above the high tide mark covered with grasses and shrubs.

Front 7

Salt marsh

Back 7

A tidal ecosystem in estuaries and deltas consisting of mud flats with salt-tolerant grasses and plants.

Front 8

Biodiversity

Back 8

The variety of species in an ecosystem

Front 9

Hard engineering

Back 9

the use of concrete and large artificial structures by civil engineers to defend land against natural erosion processes.

Front 10

Soft engineering

Back 10

Managing erosion by working with natural processes to help restore beaches and coastal ecosystems.

Front 11

hydraulic action

Back 11

the power of the waves hitting the coast

Front 12

Abrasion

Back 12

Waves pick up stones and hurl them at the coast

Front 13

Corrosion

Back 13

Sea water gradually destroys some rock components

Front 14

attrition

Back 14

material carried by waves bumps against other material and is worn smaller and smoother

Front 15

Beaches

Back 15

Accumulations of sand and shingle formed by deposition and shaped by erosion, transportation and deposition.

Front 16

Spits

Back 16

Long narrow beaches of sand or shingle that are attached to the land at one end. The extend across a bay or estuary or where a coastline changes direction. They are formed by longshore drift and powered by a strongly prevailing wind.

Front 17

Concordant coastline

Back 17

Where the rock outcrops run parallel to the sea. (For example the south or the Dorset coast)

Front 18

Discordant coastline

Back 18

Rocks outcrop at right angles to the sea, forming headlands and bays. (For example the east of the Dorset coast)

Front 19

How Geology affects the coast

Back 19

Less resistant rocks are eroded more than the resistant rocks, this can lead to a coastline of headlands and bays.

Hard rock forms high, rugged, steep cliffs. Softer rocks are generally less high, less steep and usually have evidence of slumping.

Front 20

Examples of soft rock

Back 20

Clays and sands

Front 21

Examples of hard rock

Back 21

Chalk or limestone

Front 22

How vegetation affects the coast

Back 22

Helps to protect and preserve coastal landforms. Over time features such as sand dunes will be colonised and "fixed" by vegetation.

Front 23

Submergent coastlines

Back 23

Produced by rising sea levels, features rias (drowned river valleys) and fjords (drowned glacial valleys)

Front 24

Emergent coastlines

Back 24

Produced by falling sea levels, features raised beaches (old wave-cut platforms and beaches now above sea level) and relict cliffs.

Front 25

How human activities affect the coast

Back 25

Human activities can transform the landscapes and features of the coast. It is mainly effected by, settlement, economic development and coastal management.

Front 26

Threats to coral reefs

Back 26

Pollution, overfishing, quarrying of coral for building stone and warming sea temperatures (this causes coral bleaching)

Front 27

Threats to mangroves

Back 27

Economic development is the main threat, fish and shrimp aquaculture in south-east Asia has involved large scale clearance of mangroves. Mangroves are felled for timber and fuel, and their deforestation clears land for development.

Front 28

Threats to salt marshes

Back 28

Development, agricultural and industrial pollution and rising sea levels

Front 29

Threats to sand dunes

Back 29

There are issues with over-use of dunes for recreation, causing loss of vegetation and the "blow out" of the dune.

Front 30

Stakeholders

Back 30

people with different interests in the coast

Front 31

Sea wall (Hard engineering)

Back 31

A wall, often made of concrete, which protects the coast from waves (e.g. in Hornsea)

Front 32

Groynes (Hard engineering)

Back 32

Wood or steel piling built at right angles to the beach that traps beach material being moved by longshore drift (e.g. in Hornsea)

Front 33

Rip-rap (Hard engineering)

Back 33

Large boulder piled up to protect a stretch of coast.

Front 34

Beach replenishment (Soft engineering)

Back 34

Pumping or dumping sand or shingle back onto a beach to replace eroded material being moved by longshore drift.

Front 35

Fencing, hedging and replacing vegetation (Soft engineering)

Back 35

Helps stabilise sand dunes or beaches and reduces wind erosion

Front 36

Cliff regarding (Soft engineering)

Back 36

The angle of a cliff is reduced to reduce mass movement.

Front 37

Managed retreat

Back 37

Abandoning existing coastal defenced and allowing the sea to flood inland until it reaches higher land or a new line of sea defences.