Feedback Systems Management Of Coastlines Flashcards
Introduction - feedback systems - to a significant extent
There are negative feedback systems where initial change to the system is reduced and system returns to the equilibrium, and positive feedback system where initial change to the system is exacerbated and brings system further to disequilibrium. There are examples of both negative and positive feedback systems operating along the coastline. Thus to a significant extent understanding of feedback systems can help with management of the coastal landscapes.
Paragraph 1 - agree - erosion - positive feedback system
For example, erosion operating along the coastline leads to fast coastline retreat, especially in places with predominantly weak rock such as boulder clay on the Holderness coast. This creates a positive feedback loop with higher amount of output produced than input to the system bringing the system to disequilibrium. With predicted higher sea levels, longshore drift and high wave energy, rates of erosion will only increase over time. Thus, an understanding of present and future challenges helped to create a coastal management plan and protect coastal communities, such as in case of the Mappleton.
Ao1 - paragraph 1 - Mappleton
The average rate of erosion along the Holderness coastline is 2 meters per year due to the weak boulder clay and high-energy environment
In 1990, Mappleton was under threat from loosing 30 houses and its main road.
The £2 million project created two large rock groynes to trap materials that are carried in the waves during longshore drift. In addition to this, a revetment consisting of large granite boulders has been constructed.
Evaluation paragraph 2 - understanding of fs is not necessary it can be led by the need to protect coastal communities
It can be argued that an understanding of a positive feedback system of high erosion rates may not be necessary to manage the coastline, as the decision to protect the coastline can be made based solely on the fact of the need to protect the coastal communities. Nevertheless, the understanding of feedback systems in this case would still be to a significant extent useful to choose the right hard-engineering strategy that would be sustainable in the long term.
Paragraph 2 - ineffectiveness of coastal management - leave coast to natural processes
On the other hand, it can be argued that with time coastal management methods that can be implemented will become less effective in protecting coastline from erosion. Therefore the coastline should be initially left to the natural process especially considering high financial costs of hard-engineering strategies used to protect cliffs , until the erosion would reach more resistant chalk and reduce in it’s rates, so that the system would return to it’s equilibrium state.
Ao1 - paragraph 2 - Aldbrough
Aldbrough is located approximately 10 km south-east of Hornsea on the coast of the East Riding of Yorkshire.
The cliffs here are rapidly eroding, so that Seaside Road now terminates at the cliff edge. At high tides the lower and, in some cases, middle sections of the cliff are subject to considerable erosion by wave action
Annual recession rate for the caravan site at Aldbrough is reported to be 2.16 m for the period 1951 to 2004.
Evaluation - paragraph 3 - decision to leave the cliff to nature still requires an understanding of feedback systems - wave-cut platform - rates of erosion decrease
Such a decision would still require an understanding of a negative feedback systems. As the cliff collapses after being exposed to high rates of erosion and wave action, a layer of flat rock is left behind forming a wave-cut platform, this will have a significant impact on the ability of waves to erode the base of the cliff. The waves will have to travel further in shallower water as the platform grows. Waves will then tend to break earlier before they can reach the face of the cliff, thus over time rates of erosion will slow down, bringing the system back to the equilibrium due to the operation of a negative feedback loop.
Paragraph 3 - ICZM - aims to bring coastal systems back to equilibrium
Coastal management strategies have in aim to return coastal systems to equilibrium. Integrated coastal zone management (ICZM) scheme is an example of holistic approach to coastal management that prioritises a sustainable future development of the coast which responds to changes, always seeking to restore balance in coastal systems. An example of such scheme is Triton project. It is aimed at protecting coastal areas and reducing the consequences of coastal erosion due to natural causes, such as high wind and wave energy, and human induced causes such as urban expansion, tourists development and infrastructure. In this context the project has in aim to return the coast to a more stable equilibrium in a sustainable way.
AO1 - paragraph 3 - Triton project in Italy and Greece
Triton project has a total budget of € 858.00.
Triton project is a model of integrated coastal zone management between Puglia, Italy and Western Greece.
Triton project lasted 6 years from 2014-2020.
Conclusion
In conclusion, to a significant extent understanding of feedback systems operating on the coastline can help with management of coastal zones. AS it was seen on the example of Mappleton on the Holderness coastline, understanding of the positive feedback system of high rates of coastal retreat due to high rates of erosion helped to implement the hard-engineering strategies. Nevertheless, it can be argued that the decision to protect the coastline could have been made bas solely on the intention to preserve coastline communities, infrastructure and building. In this case, understanding of positive feedback system would still be helpful to chose the hard-engineering strategy that would be sustainable in addressing higher rates of erosion in the long-term. On the other hand, it can be argued that for example ‘no intervention approach’ does not require an understanding of feedback systems, as nature is allowed to erode the coast until the hard-rock is reached and consequently the rates of erosion will decrease. This approach still requires some understanding of feedback systems, as when the cliffs collide wave-cut platforms are left, which would prevent cliffs from further erosion by reducing wave action, thus a negative feedback loop will operate to reduce the rates of erosion operating along the coastline. Understanding of feedback systems is especially necessary for such holistic approaches to coastal management as ICZMs, which promote sustainable long-term management of the coastlines. As it was seen on the example of triton project understanding of the feedback systems to a significant extent helped to provide a scheme to affectively assess and address high erosion rates. Therefore, understanding of the feedback systems are to a significant extent helpful in managing the coastlines on local and international scale for their sustainable development in the long-term.
