Coastal Erosion- Soft engineering methods.

Beach Nourishment-

This involves replacing sediment that has been lost through long shore drift or erosion. The sediment that has been moved further down the beach is moved back to its original area of the beach by local authorities. The longer incoming waves have to travel the more power they lose, this process creates a wider beach which reduces the power of the waves that hit the beach. As a result of this the amount of coastal erosion, such as hydraulic action, the beach is subjected reduces. This process usually takes place in between the tourist season, in order to reduce disruption. It costs around £3000 per 
km, the process will need to be repeated fairly regularly in order to
maintain the coastal defense.

Managed Retreat-

Managed retreat is a method whereby we allow the sea to erode and create land forms such as spits and salt marshes. Cliff erosion is allowed to occur in areas of low value farmland, farmers are then compensated for their losses. This method is cheaper than constructing more expensive coastal defenses. This can only work where the coasts of compensation are significantly less than the coasts of building coastal defenses.
It can also be beneficial to plants and animals by providing new 
habitat. The cost of this coastal defense depends

on the amount needed to compensate local people.

Sand Dunes Regeneration-

Sand Dunes often form naturally however they are fragile and come under threat because of people walking over them. Sand Dune regeneration involves using fencing to help trap sand and planting vegetation to reinforce the Sand Dune. By encouraging the formation of Sand Dunes the coastline is protected, this is because Sand Dunes intercept and absorb storm and wave energy. This costs around £2,000 per 100m.

Do Nothing-

This a method that is similar to Managed Retreat, however there are no costs at all for the local authorities. This method of doing nothing and letting nature take its course only occur in uninhabited areas of the country. These areas are not considered valuable by the government as they do not have people, houses, businesses or public buildings. This is by far the cheapest method of coastal defence as it costs the local authorities nothing.

The Demographic Transition Model.

The Demographic Transition Model:

Development indicators:

These are development indicators, they help to judge how developed a country is:

• 
  
•     Literacy rate- Total percentage of the population aged 15 and above who can read and write.
• 
  
•     Infant Mortality-the number of deaths of infants under one year old per 1,000 births.
• 
  
•     Death Rate-  The total number of deaths per 1,000 of a population in a year.
• 
  
•     Birth Rate- The total number of live births per 1,000 of a population in a year.
• 
  
•     Life Expectancy- The total number of years on average a person from a particular country is expected to live for.

Some of these development indicators contribute to calculating which stage of the

Demographic Transition Model (DTM) a particular country appears in.There are five stages to

the DTM.

My DTM revision sheet:

10 Mark Question- Internal Factors UK

Describe and explain how internal factors have caused changes in the UK population in the 20^th Century.(10)

In the early 20^th century an equal rights movement lead by The Suffragettes swept over Britain. It lead to changes in attitude and gave women more freedom and opportunities. As a result of this, women felt free to pursue their own career and delayed having children or had fewer children all together. This caused a reduction in the UKs birth rate.

The establishment of the NHS in 1948 meant that free health care was offered to everyone. This lead to an increase of around 30 years in the UKs life expectancy. In addition to this the increasing number of students studying A-levels and university caused changes in employment. More jobs in the tertiary sector caused changes to social status and resulted in increasing numbers of middle class people. The quality of life was increasing drastically in the UK throughout the 20^th century.

The increasing number of jobs in the tertiary sector were mainly focused around the south-east of the UK. In contrast the north of England suffered a huge loss of jobs due to the decline of the secondary sector. This led to a surge of people internally migrating from the north to the south-east of England, in search of work.

15 Mark Question- Aging population.

An aging population can bring economic, political and social advantages as well as disadvantages. (15)

An aging population results in a greater need for residential homes, to accommodate for the increasing number of elderly people who are living longer due to an increase in world life expectancy of 74 years by 2050. The building of more residential care homes create jobs for builders and other labourers. This is an economic advantage as it allows builders, plumbers and electricians to earn money to provide for their families and put back into the economy.

Elderly grandparents often provide free child care for their children this allows them to work more hours and build careers. They will be reassured of their children’s wellbeing because they trust their parents to look after them properly. Professional childcare can be very expensive, therefore having the grandparents there to care for their children saves them a lot of money. Grandparents often enjoy looking after their grandchildren and have a lot of experience and wisdom to pass onto them. This is therefore a social advantage of an aging population.

Due to the aging population, in the UK, 1.9% of the population is aged 85 years old or older. This makes the elderly a big target audience for political parties. Having the elderly on board with their campaigns could dramatically boast their chances of being elected. This is known as the ‘Grey vote’, stereotypically older people are more likely to vote in the general election than the youth of the country. Therefore being able to focus on getting the older generations votes, as they are a big proportion of the population, is a political advantage of an aging population.

However there are many disadvantages to a country having an aging population. The general increase of the world’s average life expectancy means that people will require more of the world resources. For example an aging population can put extra strain on a country’s healthcare system, as generally the older a person gets the more their health deteriorates which will increase their use of the healthcare system. This put healthcare resources such as doctors, nurses, medicine and hospital beds under strain which results in the government having to spend more money to try to accommodate the aging population’s needs. This is therefore an economic disadvantage of an aging population.

In the UK, due to a significant rise in the population aged 65 and over which in 2014 was at 11.1 million (17.4% of the population). In order to cope with this surge of older people the government have increased the retirement age, this requires people to work for longer. This is a social disadvantage as some people have aspirations to take their savings and travel the world for example. The government raising the retirement age restricts people’s ability to live their lives the way they planned to.

       

In order to fund the extra services we need to manage an aging population, the government have had to increase taxes. To be able to house this aging population more residential care homes and adapted bungalows have had to be built. Also more doctors and other medical staff have to be employed to be able to continue offering free health service to the elderly population, who need it most. This angers working people, who make up a large amount of the votes in the general election. This is a disadvantage for political parties as they could be at risk of losing the election due to their decision to raise taxes, even though realistically this has to be done to cope with the strain an aging population puts on our resources.

River Landforms.

River Landforms:

• Potholes- These are small circular depressions in the river bed, they are formed when rocks are drilled into holes on the river bed in a whisking action. Corrasion can also contribute to the formation of pothholes. They are commonly found at the botttom of waterfalls e.g High Force Falls.
  
• Braiding- When a river is overloaded and as a result starts to divide between small islands of deposition.
  
• Floodplain- This is a flat area of land on either side of a river which sometimes floods.This makes it very fertile.

• Levees- Small hill type structure on the riverside (Outside of channel), formed by dropped material when a river floods.  

River Transportation.

River Transport:

• Solution- Minerals are dissolved in the water and carried along in solution.

• Suspension-Fine light material is carried along in the water.

• Saltation: Small pebbles and stones are bounced along the river bed.

• Traction: Large boulders and rocks are rolled along the river bed.

• River Capacity: The capacity is the maximum load a river can transport. Capacity will also increase with increasing discharge and velocity.

• River Competence:The competence of a river is the maximum particle size that it is able to transport. The velocity of the river increases it is able to transport larger particles and so its competence increases.

Why does deposition occur?

Deposition may take place when a river enters an area of shallow water or when the volume of water decreases - for example, after a flood or during times of drought. Deposition is common towards the end of a river's journey, at the mouth. Deposition at the mouth of a river can form deltas.

Erosion.

Types of erosion:

Hydraulic action- The force of the water forces air into cracks increasing pressure causing parts to break off. The force of the water hitting river bank cause weathering.

Abrasion- Big sediment particles rub against river banks creating a sand paper effect. If this occurs on the riverbed under high pressure then pothholes can be formed.

Attrition- Big rocks that are being carried by the river smash against each other. This results in them becoming smaller and smoother.

Solution/Corrosion- Carbon dioxide dissolves in the river to form a eak acid. This dissolves rock be channel processes.