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coastal landcapes and change- EQ4 managing coastlines - Coggle Diagram
coastal landcapes and change-
EQ4 managing coastlines
consequences of coastal recession
the increased rate of coastal recession is creating greater risk for coatsla communities
economic and social losses
-coastal recession and flooding create series ecnomic and social losses
-the damage to houses and buisinesses mean that people are forces to relocate whilst repeairs are done and financial support is needed to supoort this
-many people in less developed countries have limited financial assests and are reliant on international aid
-in more developed countries like the UK, many people cant get enough insureance to cover potential damaged and many houses lose value as the rate of coastla recession increases
south west UK railway line
-in 2014 heavy strosms damaged the railway line that provided a key connection for commuters traveling between devon cornwall and other parts of the uk
-it is estimated that the 2 month closure of the railways line for repairs cost the UK economy £1.2 billion through disruption to the tourist and fishing industries in the local area
austrailian coastal flooding
-rising sea levels in australia are increaing the risk of coastal flooding
-a $2016 billion of key infastructure such as road and rail neyworks, residential housing, commercial properties and emergency service stations are at risk in the future if sea levels continue to rise
the maldives
-the maldives made up of over 1,000 islands is one of the lowest lying countries in teh world. the maldives is at serious risk of bring completly submerged because of coastal flooding
-the islands rely on tourism events threaten the physical features that cause many people to flock to the islands in search of paradise
-coastal flooding also threatens housing and freshwater sources, whih has fourced many locals to migrate away from teh annual flooding
engineering managment approaches
coastal defrences-hard engineering
hard engineering stratagies aim to reduce the effects of flooding and erosion by building man made structures that control the seas flow
rip-rap
-simply a pile of boulders. they are often placed in front of sea walls to dissipate the waves energy and support unstable rock structures
they are long lasting and relatively cheap
but they provide a hazard for people accesing the beeach and have gaps between the rocks allowing erosion and weathering to continue
revetments
-revetments are angles walls places just offshore to assist in breaking dow the force of the waves to reduce their ability to erode the coastline
they are a more cost effective techniuque to a sea wlal and reduce the rate of erosion
-but they often require regular maintenence and can create accress peoblems on the beach
offshore breakwaters
-made up of rocks placed in a line parrallel to the shore
they provide calmer conditions behind the breakwater, allowing the ebach to be used sadely for recreational sports
-but they can cause wave patterns to change and are expensive to install
sea walls
-made of hard concrete that deflects waves. they are often curved to dissipate the waves energy and refract it back towards the sea
they are a good long term solution because of the resistence of concreate keading to less maintentnce
-but they create a strong backwash that can undercut the wall and they are expensive to build and maintain
groynes
-groynes are stone or wooden fences thats tick out at 90 dgrees to teh coast. they stop material being ransportes long distances by longshoredrift
they create wider beaches which slows down waves and so reduces erosion and flooding. they are also relatively cheap
but beaches further down the coast get narrower, which means waves are not slowed down and erosion and flooding are more likely
coatal defences- soft engineering
aim to reduce the effects of flooding and erosion using our understanding of the sea and woking sustainably
beach nourishment and reprofiling
-involves moving material to the upper sections of beaches from elsewhere
-slows down waves by widening beaches and so reduces the risk of erosion ad flooding
maintains beach for tourist use, supports local economy
but removing sand and shingle from the seabed threatens certain organisms eg corals. it is also expensive and must be reapeated
cliff re grading
-cliff re grading and drainage inolves restructuing and supporting the cliff to prevnt further collpase from weathering and mass movement processes
this maintains the cliff and provides a natual environment for plant and wildlife to continue to flourish
but there are risks associated with alerting cliff profiles which can lead to further collapsing and unintedned changes to the profile
dune stabilisation
-involves the creation or restoration of sand dunes to maintain their protective position. this can be achieved through nourishment or planting vegitation
this provides a natural barrier to coastal flooding and can support wildlife habitats
-but only a small area is protected and it is ineffective in preventing wave action during powerful storms
governance approaches
integrates coastal zone management (ICZM)
the integrated coastal zone managment (ICZM) is a holistic approach to coastal managment
-deals with coastal amnagment stratagies
-work involves careful consideration of the most effective maanagment approach for a stretch of coastline
-considers social, economic and environmental implications
-conecpt was created by world leaders at earth summit in 1992
factors of consideration
-stakeholders consider the fllowing factors whne decideing the type of coastal managment thats should be adopted on a coastline
the proposed risk to residential, commercial and industrial buildings
the implication of coastal recession on the local economy
the impact of coastal recession and flooding on the natural environment
leaders opinions
-they beleive the use of ICZM brings the folliowing benefits to coatsla regions:
promotes the careful conservation of natural environment
encourages the efficient use of resources to reduce unnessesary costs
-tries to reduce the potential loss to teh varies stakeholders that rely on coastal regions for their livelihood
shoreline managment
the UK coastline consists of 11 sediment cells. each has an SMP (shoreline managment plan) that has been devised by key organisations to determine the most appropriate managemennt stratagies for aa stretch of coastline. here are 4 key managment approaches
no active intervention
-no mangement used along the coastline with physical proncesses alowed to work maturally
strategic realignment
-physical processes allowed to work nturally, with monitoring and intervention only when necessary
hold the existing defences
-hold the existinf defences- maintaiing the extiting defences to make sure they can continue to be effective
advance the line
-the construction of new engineering techniques to protect the coastline from further recession
CBAs and EIAs
cost benefit analysis , environmental impact assesments are used to help determine whether or not managing the coastline is worthwhile
CBA and EIA
-A CBA is used to determine the economic value of a coatine to decide if intervention is needled in order to protect the surrounding land
-an EIA is used to access the short and long term implications of using managment stratagies on the environment
