1.1.10: Human activity and management on coasts Flashcards
Positive impacts of coastal processes on human activity
6
Recreation and tourism residential job opportunities agriculture industry transportation
Agriculture in coastal areas
example
Can drain tidal mud flats to use for farming
Industry in coastal areas
example
Rias provide deep water ports needed for importing material
Transportation in coastal areas
example
Rias allow deep water vessels to travel inland and flat marine terraces above sea level are ideal for rail and road communications
Reasons tourists attracted to coastal areas
4
natural features
deep water ports have cruise ships
rebranding and marketing by coastal resorts
to visit places from tv or films
Negative environmental impacts of tourism in coastal areas
3
footpath erosion
damage to ecosystems
unsustainable demand for water
Negative social and economic impacts of tourism on coastal areas
6
infrastructure overload
commercialisation of local culture
increase in second home owners
vulnerability of reliance on 1 economic activity
closing of facilities out of season
many of the jobs are seasonal and low- paid
Positive social and economic impacts of tourism on coastal areas
2
local people earn a living through providing services for tourists
multiplier effect
Negative impacts of coastal processes on human activity
6
rapid mass movement events coastal erosion loss of beach sediment erosion of vulnerable ecosystems sea-level rise increase in sediment input
Management strategies
5
do nothing managed retreat/ realignment hold the line advance the line limited intervention
Management strategy
do nothing
Allows natural processes such as coastal erosion to continue
Management strategy
Managed retreat/ realignment
Allows the shoreline to move inland by erosion or flooding to a new line of defence
Management strategy
Hold the line
The present shoreline is protected by a variety of hard and soft engineering
Management strategy
Advance the line
The shoreline is moved seawards either using hard engineering structures or by encouraging sand dune growth
Management strategy
Limited intervention and examples
Deals with the problem to some extent
eg: encouraging growth of salt marshes or sand dunes or raising buildings
Choice of management strategy depends on these factors
4
Feasibility
Cost-benefit analysis (CBA)
Environmental impact analysis (EIA)
Risk assessment
Feasibility
and example
Considers the technical aspects
for example: is an engineering solution possible given marine processes and factors such as geology?
Cost-benefit analysis (CBA)
Divides the value of the benefits by costs and benefits should outweigh the costs for a strategy to be adopted
Environmental impact analysis (EIA)
Considers the effects on the environment on the immediate area and down the coast
Risk assessment
and example
Weighs up the value of what is at risk against management strategy
eg: Considers factors such as recurrence intervals of storms and the strategy to prevent and how long it should last
Examples of hard engineering
8
sea walls rock armour revetments gabions groynes drainage offshore bars rock bund
Sea walls
Concrete structures at the cliff foot absorb wave energy
Rock armour
Large rocks placed to absorb wave energy
Revetments
Wooden or concrete structures that absorb wave energy while allowing some flow of sediment
Gabion cages
Steel cages filled with small rocks to add strength to a coastline
Groynes
Wooden structures jutting into the sea to trap longshore drift
Drainage
drains in cliffs to remove water and thus prevent land slips
Offshore bars
islands of boulders offshore to absorb the force of the wave before they reach land
Rock bund
A row of rocks along a beach
Examples of soft engineering techniques
6
beach replenishment beach reprofiling beach recycling fencing/hedging replanting vegetation cliff profiling
Beach replenishment
Sand or shingle is added, extending the beach or replacing eroded material
Shingle
pebbles/cobbles
Beach reprofiling
beach shape is changed to absorb more energy, reducing erosion
Beach recycling
sediment is moved along the beach to counteract longshore drift
Fencing/hedging
Preserves beach or dunes by reducing the amount of sand blown away
Replanting vegetation
planting grasses or salt-resistant plants to stabilise areas, reducing erosion
Cliff profiling
Reducing the cliff angle, making the cliffs more stable
Conservation strategies
3
Wold heritage sites
National marine reserves
Sites of special scientific interest
Offshore dredging
the extraction of sand and gravel from the seabed for use in construction, especially of sea defences
Offshore dredging negative effects
2
destruction of seabed habitats and marine food webs
changes to wave types and sediment flows, resulting in changes to beach profile
Human impacts on sand dune environments
4
conversion
removal
overuse
external factors
Conversion of sand dunes
The dune area is used for urbanisation or activities such as golf courses. Natural vegetation is altered or removed, changing the dune environment
Removal of sand dunes
Sand is removed for another use which allows further erosion by the wind
Overuse of sand dunes
Used as an amenity for recreation activities, tourism or as military training areas. Overuse results in vegetation removal, increasing the rate of wind erosion
External factors affecting sand dunes
Human activity in another part of the coast affects the dune system
eg: the building of defences reduces sediment input to the dunes
Management of sand dunes
3
complete reconstruction
restoration by revegetation and fencing
removal of external factors
Integrated coastal zone management (ICZM)
Form of sustainable management which tires to balance environmental, social, economic, cultural and recreational needs within the limits controlled by natural factors
