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Geography Paper 1 - Physical Geography > Section B - Coastal Landscapes and Change > Flashcards

Section B - Coastal Landscapes and Change Flashcards

1
Q

What is a high-energy environment?

A

Where the rate of erosion exceeds the rate of deposition

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2
Q

What is a low-energy environment?

A

Where the rate of deposition exceeds the rate of erosion

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3
Q

Characteristics of high energy coastlines?

A

Older resistant rock (igneous, sedimentary and metamorphic) that are all resistant to the erosive powers of the sea, wind and rain

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4
Q

Characteristics of low energy coastlines?

A

Weaker and younger sedimentary rocks including clays, chalks, sand and sandstone - more susceptible to erosion - leaves areas of low, flat relief or coastal plains

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5
Q

Inputs of the coastal system (4)

A

Marine - waves, tides, storm surges
Atmospheric - weather/climate, climate change and solar energy
Land - Rock type and structure, tectonic activity
People - Human and coastal management

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6
Q

Processes of the coastal system (5)

A

Weathering
Mass movement
Erosion
Transport
Deposition

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7
Q

Outputs of the coastal system (3)

A

Erosional landforms
Depositional landforms
Different types of coast

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8
Q

What is the littoral zone?

A

An area of the coastline which has all features of a complex coastal system - inputs, outputs and processes

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9
Q

The four ways in which coasts can be classified?

A

Geology - this can create rocky, sandy, estuarine, concordant and discordant coasts
Energy levels - high or low energy coastlines
Balance between erosion and deposition - creating either erosional or depositional coasts and their features
Changes in sea level - creating emergent or submergent coasts

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10
Q

What is coastal morphology?

A

The shape and form of coastal landscapes and their features - related to underlying geology, rock type and geological structure (lithology)

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11
Q

What is strata?

A

Layers of rocks

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12
Q

What are bedding planes?

A

Horizontal cracks - natural breaks in the strata caused by gaps in time during periods of rock formation

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13
Q

What are joints?

A

Vertical cracks - Fractures caused by either contractions as sediments dry out or by earth movements during uplift

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14
Q

What are folds?

A

Formed by pressure during tectonic activity which makes rocks buckle and crumple (EG Lulworth Cove)

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15
Q

What are faults?

A

Formed when the stress or pressure to which a rock is subjected exceeds its internal strength causing it to fracture - the faults then slip or move along fault planes

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16
Q

What does dip refer to?

A

The angle at which rock strata lie (horizontally, vertically, dipping towards to sea or dipping inland)

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17
Q

Characteristics and examples of igneous rocks?

A

Resistant and permeable (EG granite) - very slow recession rate - recedes at less than 0.1cm per year

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18
Q

Characteristics and examples of sedimentary rocks?

A

Formed in strata (EG limestone, chalk, sandstone and shale) - recedes moderately quickly (0.4-10cm per year)

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19
Q

Characteristics and examples of metamorphic rocks?

A

Very hard, impermeable and resistant (EG marble and schist) - slow recession rate - 0.1-0.3cm per year

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20
Q

What are concordant coasts?

A

Where bands of more resistant and less resistant rock run parallel to the coast

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21
Q

What are Dalmatian coasts?

A

Coastlines where valleys and ridges run parallel to each other - when they are flooded the tops of the ridges remain above the water as a series of offshore islands (EG Dalmatian coast in Croatia)

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22
Q

What are Haff coasts?

A

Long spits of sand and lagoons aligned parallel to the coast

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23
Q

What are discordant coastlines?

A

Where the geology alternates between bands of more resistant and less resistant rock - forms bays at low resistance and headlands at more resistance

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24
Q

What are headlands?

A

Headlands force the oncoming waves to refract or bend – concentrating their energy at the headlands – this increases the waves’ erosive power which leads to a steepening of the cliffs and their eventual erosion into arches and stacks

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25
Q

What are bays?

A

When waves enter a bay, their energy is dissipated (spread out) and reduced – this leads to the deposition of sediment (sand or shingle) forming a beach

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26
Q

Marine processes - Erosion definition

A

The break down and removal of materials by water wind and ice - EG hydraulic action, abrasion and corrosion, attrition and solution

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27
Q

Types of erosion - Hydraulic Action

A

The process by which breaking waves compress pockets of air in cracks in a cliff - the pressure may cause the crack to widen, breaking off the rock

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28
Q

Types of erosion - Attrition

A

Erosion caused when rocks and boulders transported by waves bump into each other and break up into smaller, smoother, more rounded pieces

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29
Q

Types of erosion - Abrasion

A

The wearing away of cliffs by sediment rubbing against a rock platform

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30
Q

Types of erosion - Solution/corrosion

A

Soluble particles dissolving into the sea

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31
Q

Landforms created by coastal erosion - wave-cut notch

A

When waves break against the foot of a cliff, erosion tends to be concentrated close to the high tide line - this creates a wave cut notch which begins to undercut the cliff - as the wave-cut notch gets bigger, the rock above becomes unstable and eventually the upper part of the cliff collapses

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32
Q

Landforms created by coastal erosion - wave-cut platform

A

As wave-cut notches get bigger, they migrate inland and the cliff retreats, leaving behind a wave cut platform - waves will break earlier and dissipate meaning these only extend a few hundred meters

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33
Q

Landforms created by coastal erosion - cliffs

A

Constant wave action and erosion against the base of the cliff ensure that it maintains a steep profile as it retreats inland - steepest cliffs = vertical or horizontal rock strata - gentlest = where rock dips towards or away from the sea

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34
Q

Describe the process of waves, arches, stacks and stumps?

A

Erosion of rocks EG limestone and chalk tends to exploit lines of weakness EG joints, faults and cracks - when joints and faults are eroded by hydraulic action and abrasion, this can create caves – if the overlying rock then collapses, a blowhole will develop as the cave opens up at ground level – during storm high tides, seawater can be blown out of these blowholes with considerable force

If two caves on either side of a headland join up, or a single cave is eroded through a headland, an arch is formed – this gap is then further enlarged by erosion and weathering – becoming wider at the base

Eventually, the top of the arch will become unstable and collapse leaving an isolated pillar called a stack – the stack itself will continue to be eroded by the sea and as it collapses and is eroded further, it may only appear above the surface at low tide, and is now known as a stump

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35
Q

Process of sediment transport - LSD

A

Waves approach beach at angle of prevailing wind, carry sediment up beach at angle - backwash then pulls sediment back down at right angles to the beach - net movement is a lateral shift of sediment down the beach

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36
Q

What are the six coastal depositional landforms?

A

1) Spits
2) Beaches
3) Offshore bars
4) Barrier beaches (bars)
5) Tombolos
6) Cuspate foreland

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37
Q

Coastal depositional landforms - Spits

A

Long narrow feature made up of sand or shingle on drift aligned beaches - sediment moved along by LSD but if a coast suddenly changes direction a spit will build across the estuary mouth

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38
Q

Coastal depositional landforms - Beaches

A

Commonly found in bays where wave refraction creates a low energy environment which leads to deposition - can consist of either sand or shingle and be swash aligned or drift aligned

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39
Q

Coastal depositional landforms - Offshore bars

A

Submerged ridges of sand or coarse sediment created by waves from offshore of the coast - destructive waves erode the sand from the beach with their strong backwash and deposit it offshore in bars

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40
Q

Coastal depositional landforms - Barrier beach (bars)

A

Where a spit extends across a bay to join two headlands, it forms a barrier beach EG Loe Bar in Cornwall - can trap water behind and form lagoons - where a beach becomes separated from the mainland this is called a barrier island

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41
Q

Coastal depositional landforms - Tombolos

A

A beach that has formed between a small island and the mainland - deposition occurs when waves lose their energy and the tombolo begins to build up

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42
Q

Coastal depositional landforms - Cuspate forelands

A

Triangular shaped headland that extends out from the main coastline - occurs where a coast is exposed to LSD from opposite directions - sediment is deposited at the point where the two meet which helps to form a natural triangular shape as it builds up - as vegetation grows on the cuspate foreland it helps stabilise it and protect it from storms and erosion

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43
Q

Stabilising depositional landforms - sand dunes

A

Sandy beaches may be backed by sand dunes formed by sand which has been blown off the beach by strong winds - dunes can develop where sand is initially trapped by debris towards the back of the beach and are stabilised by plant succession

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44
Q

Stabilising depositional landforms - plant succession

A

Bare ground gradually consolidated by pioneer species - pioneer species modify the environment by binding soil and adding nutrients when they die - creeping plants then help the sand retain moisture which allows species to colonise - this then stabilises the land as more species develop - the final community will then be adjusted to the climatic conditions of the area - known as the climatic climax community

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45
Q

What is a sediment cell?

A

Systems with sources, transfers and sinks - amount of sediment available in a sediment cell is called the sediment budget - within each cell, depositional figures are in equilibrium with the amount of sediment available - if the sediment budget falls depositions increases but if the sediment budget increases more deposition is likely - the ways in which the system attempts to balance this is known as dynamic equilibrium

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46
Q

What are sub-aerial processes?

A

Sub-aerial processes are land based processes which alter the shape of the coastline - these are a combination of weathering and mass movement

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47
Q

What is weathering?

A

The gradual breakdown of rock in situ at or close to the ground surface - divided into mechanical, chemical and biological - by breaking down rock, weathering creates sediment which the sea can use to help erode the coast

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48
Q

Types of mechanical weathering? (3)

A

1) Freeze-thaw weathering
2) Wetting and drying
3) Salt-weathering

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49
Q

What is freeze-thaw weathering?

A

Water seeps into cracks in rocks and freezes - this then expands by about 10% - repeated freeze thaw weathering puts pressure on the rocks until they crack and break the rock - usually occurs when the temp oscillates around freezing point - shattered fragments of rock collect at the bottom of the cliff as scree

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50
Q

What is salt crystallisation?

A

When salt evaporates, it leaves salt crystals behind - these can grow over time and exert stresses in the rock, just as ice does, causing it to break up - salt can also corrode rock, particularly if it has traces of iron

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51
Q

What is wetting and drying?

A

Frequent cycles of wetting and drying are common on the coast - rocks rich in clay (EG shale) expand when they get wet and contract when they dry - this can cause them to crack and break up

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52
Q

Examples of biological weathering? (4)

A
  • Thin plant roots start to grow into small cracks in a cliff face – these cracks then widen as the roots grow thicker, which breaks up the rock
  • Water running through decaying vegetation becomes acidic which leads to increased chemical weathering
  • Birds and animals dig burrows into cliffs
  • Marine organisms are also capable of burrowing into rocks or secreting acids
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53
Q

What is chemical weathering? (carbonation)

A
  • Carbonation occurs when rainwater absorbs CO2 from the air to form a weak carbonic acid – this reacts with calcium carbonate in rocks such as limestone and chalk to form calcium bicarbonate which is easily dissolved – the cooler the temp of the rainwater, the more CO2 is absorbed, increasing the effect of carbonation in winter
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54
Q

What is mass movement?

A

The movement of weathered material down a slope due to gravity

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55
Q

Types of mass movement

A
  1. Flow - very slight movement - soil creep/solifluction
  2. Flow - slow to rapid movement - mudflow/earthflow
  3. Slide - slow to rapid movement - rock fall, rock slide, slump
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56
Q

What is soil creep? (flows)

A

The slowest form of MM - almost continuous process - very slow downhill movement of individual soil particles

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57
Q

What is solifluction? (flows)

A

Averages between 5cm and 1m per year - occurs mainly in tundras where the ground is frozen - when the top layer of soil thaws in summer, the surface layer becomes saturated and flows over the frozen subsoil and rocks

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58
Q

What are earth-flows and mudflows? (flows)

A

An increase in the amount of water (EG due to heavy rain) can reduce friction causing earth and mud to flow over underlying bedrock

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59
Q

What are rock falls (slides)

A

Rock falls are most likely to occur when strong, jointed, steep rick faces are exposed to mechanical weathering – on slopes over 40 degrees - material either bounces or fall vertically to form scree at the foot of the cliff - block falls are similar to rock falls – a large block of rock falls away from the cliff due to the jointing of the rock

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60
Q

What are rock/debris slides? (slides)

A

Rocks that are jointed, or have bedding planes that are parallel to the slope or cliff surface, are susceptible to landslides - an increase in the amount of water can reduce friction, causing sliding - in a rock or landslide, slabs of rock can slide over underlying rocks along a slip plane

61
Q

What are slumps (slides)

A
  • Slumps occur in saturated conditions on moderate to steep slopes - common where softer materials (clays or sands) overlie more resistant rock (granite or limestone) - slumping causes rotational scars - repeated slumping creates a terraced cliff profile
62
Q

Contemporary sea level change - Kiribati (CS)

A

Kiribati is a pacific nation consisting 33 islands in the pacific ocean - many of these will be underwater by 2050 due to rising sea levels - climate scientists predict that by 2100 average sea levels will rise by 40cm meaning Kiribati are at risk of sinking underwater

63
Q

Average global temp rise and sea level rise from 1880-2012?

A

Temp - 0.85 degrees
Sea levels - 21cm

64
Q

What are the two types of sea level change?

A

Eustatic - sea level rise
Isostatic - land rising or falling in relation to sea level

65
Q

What is eustatic change?

A

In glacial periods huge ice sheets are formed that hold water normally help in the oceans - sea levels fall as a result - at the end of a glacial period ice sheets melt and sea levels rise

66
Q

What is isostatic change?

A

During glacial periods the enormous weight of ice sheets makes the land sink – this is called isostatic subsidence - as the ice begins to melt at the end of the glacial period, the land will rise up again as the weight of the ice is lifted from it – this is called isostatic recovery

67
Q

How does tectonic activity affect sea levels? (CS)

A

On boxing day 2004, the Indian Ocean tsunami killed approximately 300,000 people - parts of Indonesia were hit by 15 metre high waves - the earthquake also caused the Earth’s crust at the affected part of Indonesia to sink – permanently flooding some areas - in the past, destructive plate margins have led to the uplift of mountain ranges and coastal land

68
Q

What is an emergent coastline?

A

An emergent coastline is created when a fall in sea level exposes land previously covered by the sea

69
Q

What is a submergent coastline?

A

A submergent coastline is created when a rise in sea level floods the coast and submerges the coastline

70
Q

Emergent coastline landforms - Raised beaches

A

As land rose due to isostatic recovery, former shoreline platforms and their beaches were raised above the present sea level - this created what is known as raised beaches which are common on the West coast of Scotland - here, the remains of eroded cliffs (relic cliffs) can be found behind the raised beach, with wave-cut notches and caves as evidence of past marine erosion

71
Q

Submergent coastline landforms - Rias

A

Rias are sheltered winding inlets with irregular shorelines (SWIWIS) - they form when valleys in a dissected upland area are flooded - common in South-West England EG the Kingsbridge Estuary in Devon

72
Q

Submergent coastline landforms - Dalmatian coasts

A

Similar to rias - long, narrow islands running parallel to the coastline - difference is that in Dalmatian coasts, the rivers flow almost parallel to the coasts rather than at right angles to it - EG Dalmatian coast in Croatia

73
Q

Submergent coastline landforms - Fjords

A

Fjords are formed when deep glacial troughs are flooded by a rise in sea level - long and steep sided with a U cross section and hanging valleys - they can be found in Norway, New Zealand, and Chile

74
Q

Factors affecting erosion at Holderness - Geology

A

Holderness coast = boulder clay - structurally weak and has little resistance to erosion - produces shallow sloping cliffs between 5-20m high - chalk band that surrounds Holderness created a headland at Flamborough Head - erosion has created features such as cliffs, arches, stacks and stumps

75
Q

Factors affecting erosion at Holderness - Fetch

A

Wave energy depends on the fetch - how far the eave has travelled - Holderness is exposed to waves from the North Sea (500-800km) from the North Sea - not that far when you compare to waves crossing oceans

76
Q

Factors affecting erosion at Holderness - LSD/beach material

A

Boulder clay erosion leads to fine clay particles which are brought out to sea through suspension - narrow beaches at Holderness mean waves hit base of cliffs regularly - LSD transports sediment South leaving cliffs at Holderness exposed as there is an imbalance of input and output of sand through swash and backwash

77
Q

Holderness erosion and sub-aerial processes

A

Chemical weathering ineffective - meachanical and biological weathering effective esp freeze thaw and wetting/drying - this leads to slumping as the main form of MM in Holderness

78
Q

Who are the four key players in the Holderness coastline?

A

1 - Central gov agencies EG Environmental Agency
2 - Local gov EG local council
3 - Stakeholders in local economy EG tourism, farming, residence and insurance groups
4 - Environmental stakeholders - EG English Nature

79
Q

The impact of coastal management at Holderness - What is going on at Hornsea and Mappleton?

A

Defences preventing erosion include sea wall, rock armour and groynes at Hornsea - this protects Hornsea but interrupts the flow of beach material by LSD - leads to starvation of sediment down-drift at Mappleton - known as terminal groyne syndrome

80
Q

How much money had the East Riding of Yorkshire Council committed to Holderness erosion?

A

Between 2010 and 2012 the council committed £1.2 million to trial different ways of helping people adapt on an eroding coastline including a relocation package

81
Q

Coastal flooding in Bangladesh - Background issues (pop and floodplains)

A
  • 169 million pop - 46% less than 10m above sea level
  • Lies on the floodplain of three major rivers - Ganges, Brahmaputra and Meghna
82
Q

Human factors increasing flood risk in Bangladesh - Removing vegetation

A

Bangladesh has the largest tract of mangrove forests in the world - helped take the sting out of the 2007 Cyclone Sidr but recent images show Bangladesh’s mangroves retreating at a rate of 200m per year due to erosion and human deforestation

83
Q

What do mangroves do?

A
  • Mangroves stabilise coastlines against erosion and create biodiversity through its ecosystems – also provide protection and shelter against extreme weather events by absorbing and dispersing tidal surges
84
Q

Impact of mangrove forests in Sri Lanka (2004 Indian Ocean tsunami)

A

Report published a year after the 2004 Indian Ocean tsunami compared the affects on two different villages, one with mangrove forests and the other without - 6000 people died in the village with no mangrove forests - only two died in the village with mangrove forests

85
Q

What are Sri Lanka doing to mangrove forests since 2004?

A

Sri Lanka have adopted a scheme that will protect all 8800 hectares of its mangrove forests and replant more mangroves to protect the coastline in the future

86
Q

Impacts of Cyclone Sidr (deaths, storm surge, injuries, cost)

A
  • 3363 deaths
  • 6m storm surge
  • 5500 people injured
  • $1.7 billion cost
87
Q

Coastal flooding in developed countries - UK

A

Mid Dec 2013 – early Jan 2014 – spell of extreme weather and succession of major storms because of low pressure weather systems across the being brought across the Atlantic - led to strong winds in Scotland and coastal flooding in the East of England - two deaths - hundreds of thousands protected by flood defences and the Thames Barrier was closed to protect London

88
Q

Coastal flooding in developed countries - Netherlands

A

Strong winds and a 3.7m storm surge - no deaths unlike in 1953 - - largely due to the building of the Delta Works – a series of dams and storm surge barriers designed to protect against flooding from the North Sea

89
Q

What impact is climate change predicted to have on the strength of winds and amount of rain by 2100?

A

Winds 11% stronger
20% more rain

90
Q

Preparing for the future - What is adaptation?

A

Making changes to lessen the impacts of flooding – includes building things like sea walls, storm surge barriers and reinstating mangrove forests

91
Q

Preparing for the future - What is mitigation?

A

Making efforts to reduce the emissions of greenhouse gases and so reduce the impact of climate change

92
Q

Stopping coastal erosion - What is hard engineering?

A

– This involves buildings structures along the coast (usually at the base of a cliff or on the beach)

93
Q

Types of hard engineering (5)

A

Groynes, sea walls, rock armour, revetments and offshore breakwater

94
Q

What are groynes?

A

Timber or rock structures built at right angles to the coast – they trap sediment being moved along the coast by LSD – building up the beach

95
Q

Advantages of groynes? (3)

A

Built-up beach increases tourist potential and protects the land behind it

Groynes work with natural processes to build up the beach

Not too expensive

96
Q

Disadvantages of groynes? (2)

A

Groynes starve beaches further down the coast of fresh sediment as they interrupt LSD – this often leads to increased erosion elsewhere

Groynes are unnatural and rock groynes can be very unattractive

97
Q

Cost of groynes?

A

£5000 to £10,000 each at 200m intervals

98
Q

What are sea walls?

A

Made of stone or concrete at the foot of a cliff or at the top of a beach – usually have a curved face to reflect the waves back into the sea

99
Q

Advantages of sea walls? (2)

A

Effective prevention of erosion

They often have a promenade for people to walk along

100
Q

Disadvantages of sea walls? (3)

A

Reflect wave energy rather than absorb it

Can be intrusive and not look natural

Very expensive to build and maintain

101
Q

Cost of sea walls?

A

£6000 per meter

102
Q

What is rock armour?

A

Large rocks placed at the foot of a cliff or at the top of a beach – it forms a permeable barrier to the sea breaking up the waves but allowing some water to pass through

103
Q

Advantages of rock armour? (2)

A

Relatively cheap and easy to construct/maintain

Often used to fishing or sunbathing

104
Q

Disadvantages of rock armour? (3)

A

Rocks are generally from somewhere else and don’t fit in with the local geology and can look out of place

Can be very intrusive

The rocks can be dangerous for people clambering over them

105
Q

Cost of rock armour?

A

£100,000-£300,000 for 100m

106
Q

What are revetments?

A

Sloping wooden, concrete or rock structures – placed at the foot of a cliff of the top of a beach – they break up the waves’ energy

107
Q

Advantages of revetments? (1)

A

Relatively cheap to build

108
Q

Disadvantages of revetments? (2)

A

They are intrusive and can look unnatural

They can need high levels of maintenance

109
Q

Cost of revetments?

A

Up to £4500 per meter

110
Q

What is offshore breakwater?

A

A partly submerged rock barrier designed to break up the waves before they reach the coast

111
Q

Advantages of offshore breakwater? (1)

A

An effective permeable barrier

112
Q

Disadvantages of offshore breakwater? (2)

A

Visually unappealing

A potential navigation hazard

113
Q

Cost of offshore breakwater?

A

Similar to rock armour - £100,000-£300,000 for 100m

114
Q

Examples of hard engineering at Holderness - Hornsea

A
  • Defences – Concrete sea walls, groynes, rock armour
  • Impacts – Groynes trap sediment and maintain the beach at Hornsea, but beaches have been starved at Mapleton downstream
115
Q

Examples of hard engineering at Holderness - Withernsea

A
  • Defences – Sea wall (replaced in 1990s by a curved wall at a cost of £6.3 million)
  • Impacts – Waves are noisier and promenade is smaller – views from sea front hotels have also been restricted
116
Q

Examples of hard engineering at Holderness - Mapleton

A
  • Defences – Two rock groynes (at a cost of £2 million) built with the aim of preventing the removal of sand through LSD
  • Impact – Coastline South of Mappleton is starved of sediment leading to increased erosion of the cliff
117
Q

What is soft engineering?

A

This approach is designed to work with natural processes in the coastal erosion system in order to manage (but not necessarily prevent) erosion

118
Q

Examples of soft engineering?

A

Beach nourishment, cliff regarding and drainage, dune stabilisation, marsh creation

119
Q

What is beach nourishment?

A

The addition of sand or pebbles to and existing beach to make it higher or wider – sediment is usually dredged from the nearby seabed

120
Q

Advantages of beach nourishment? (3)

A

Relatively cheap and easy to maintain

Looks natural and blends in with the existing beach

Increases tourist potential by creating a bigger beach

121
Q

Disadvantages of beach nourishment? (1)

A

Needs constant maintenance due to natural processes of erosion and LSD

122
Q

Cost of beach nourishment?

A

£300,000 for 100m

123
Q

What is cliff regrading and drainage?

A

Cliff regrading reduces the angle of the cliff to help stabilise it – drainage removes water to prevent landslides and slumping

124
Q

Advantages of cliff regrading and drainage? (2)

A

Regrading can work on clay or loose rock where other methods don’t work

Drainage is cost effective

125
Q

Disadvantages of cliff regrading and drainage? (2)

A

Regrading causes the cliff to retreat

Drained cliffs can dry out and lead to collapse (rock falls)

126
Q

Cost of cliff regrading and drainage?

A

Details unavailable

127
Q

What is dune stabilisation?

A

Marram grass can be planted to stabilise dunes – areas can be fenced in to keep people off newly planted dunes

128
Q

Advantages of dune stabilisation? (3)

A

Maintains a natural coastal environment

Provides important wildlife habitats

Relatively cheap and sustainable

129
Q

Disadvantages of dune stabilisation? (2)

A

It is time consuming to plant marram grass

People may respond negatively to being kept off certain areas

130
Q

Cost of dune stabilisation?

A

£200-£2000 for 100m

131
Q

What is marsh creation?

A

A form of managed retreat by allowing low-lying coastal areas to be flooded by the sea - the land then becomes salt marsh

132
Q

Advantages of marsh creation? (3)

A

Relatively cheap as it often involves land reverting to its original state pre agricultural use

Creates a natural defence providing a powerful buffer to powerful waves

Creates an important wildlife habit

133
Q

Disadvantages of marsh creation? (2)

A

Agricultural land is lost

Farmers or land owners need to be compensated

134
Q

Cost of marsh creation?

A

Depends of the size of the area

135
Q

Managing future threats - adaptation in Bangladesh

A

South West Bangladesh is at risk of serious flooding -in the last 50 years, Bangladesh has built over 4000km of coastal embankments - however plans to upgrade these have been controversial as people don’t want to give up their land - another way is by expanding mangrove forests - during ‘Super Cyclone’ Kalina, villages that had 4km of mangrove forests recorded no deaths while villages with less than 3km of mangrove forests

136
Q

Odisha’s coastal zone

A

Odisha’s coastal zone is in North-East India and is home to a wide variety of fauna and flora including mangroves - coastal fishing employs a number of workers there as well

137
Q

What is Odisha’s coastal zone under threat from? (8)

A

Odisha’s coastal zone is under stress from:
- Rapid urban industrialisation
- Marine transport, fishing and agriculture
- Tourism
- Coastal and seabed mining
- Coastal erosion
- Offshore oil and natural gas production
- An increase in the frequency and intensity of severe weather events EG cyclones
- Rising sea levels

138
Q

What is being done to help Odisha’s coastal zone

A
  • Attempted to use an ICMZ to help
  • The aim is to establish sustainable levels of social activity, resolve environmental, social and economic challenges and protect coastal environment
139
Q

What is an ICZM

A
  • Integrated Coastal Management Zone
  • ICZM is a process that brings together all of those involved in development, management and usage of the coast
140
Q

Odisha ICZM players and stakeholders (3)

A
  • Central gov - Water resource department, fisheries department
  • State and local gov - Odisha state disaster management authority, Odisha state pollution control board
    Stakeholders in the local economy - handcraft and cottage industries, Odisha tourism development corporation
141
Q

What does the ICZM in Holderness do and where does it protect?

A
  • ICZM used to protect Flamborough Head called the Flamborough Head to Gibraltar Point Shoreline Management Plan (SMP)
  • Sets out policy for coastline and flooding prevention for the next 100 years
142
Q

What are the four options for the ICZM in Holderness?

A

1) Hold the line
2) Advance the line
3) Managed retreat
4) Do nothing

143
Q

What is hold the line?

A

This involves maintaining the current position of the coastline (often using hard engineering methods)

144
Q

What is advance the line?

A

This involves extending the coastline out to sea EG by encouraging the build-up of a wider beach using groyne construction and beach-nourishment methods

145
Q

What is managed retreat?

A

This involves allowing the coastline to retreat, but in a managed way – it can involve the deliberate breaching of flood banks built to protect low quality farmland from flooding

146
Q

What is do nothing?

A

This involves letting nature take its course and allowing the sea to erode cliffs and flood low lying land (whilst letting existing defences collapse)

147
Q

Who are the key players in the Holderness ICZM / SMP (4)

A
  • National gov – Environmental Agency, Natural England
  • Local gov – Lincolnshire County Council, North East Lincolnshire Council, East Lindsey Council
  • Stakeholders in the economy – National farmers union
  • Environmental stakeholders – English heritage
148
Q

What is the plan for Holderness?

A

Cost benefit analysis concluded that
- Along the undefended parts of the coast, the ‘do nothing’ policy has no costs but their will be some economic losses (EG loss of land and houses)
- The benefits of protecting Hornsea, Bridlington and Withernsea outweighed the costs
- The economic benefits of continuing to hold the line at Mappleton is similar to the costs
- Spurn point will be allowed to evolve with minimal costs

Geography Paper 1 - Physical Geography (5 decks)

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