Monday 20 May 2013

Fieldwork: Studland Sand Dunes

Location: East coast of the Isle of Purbeck in Dorset, nearest village is Studland, close to Poole and Bournemouth

Aim: To investigate environmental and vegetation changes across Studland Bay Sand Dunes

Hypothesis: Percentage of vegetation cover and number of plant species will increase as you move inland from the embryo dunes

Why were Studland Sand Dunes Chosen?

  • Fully developed 600 year old dune system as otherwise if it was not fully developed there would be data missing leading to inaccurate conclusions
  • They are a National Nature Reserve and a SSSI owned by the National trust so they are protected and have been able to develop with  a minimum of human interference - any changes we observe in the natural environment should be linked to natural changes in the immediate physical environment
  • The dunes are accessible at all tidal times and there is no risk of being cut off at high tide - full access to the sand dune system and kept fieldwork risks to a minimum
  • The beach can have up to 25,000 visitors on it in the summer, and as the dunes are not heavily protected or patrolled we could also observe the human impact on sand dunes
  • Very accessible as close to a B road and good parking
There are:
Embryo Dunes followed by
Grassy Dunes
Then a Heather Slack
Then a main dune ridge
Then a tree line

Fieldwork: Risk Assessment

There was a pre-visit to the dunes by staff.

We discussed possible risks in groups and as a class did a risk assessment, looking at the site on google earth to help us.

Risks:
  • Sharp Dune grass causing cuts on fingers
  • Sand blowing into eyes
  • Eating poisonous plants
  • Being cut off by high tide
  • Snake bite, more serious with a venomous bite than a dry bite
  • Verbal abuse and possible physical harm from members of the public
We assigned the risks with a Severity Score and a Likelihood score each out of 5, then used these to determine an overall risk score.

eg  Sand blowing into eyes = Likelihood score: 4   Severity Score: 1   Total risk score:   4
How we would combat this: Student briefing and carrying a first aid kit with eye wash.

Snake bite   Likelihood Score: 2    Severity Score: 4    Total Risk score: 8
How we would combat this: Student brief, wearing appropriate clothing like walking boots, checking where putting quadrat down, having mobile phones to call 999

Fieldwork: Spearman's Rank Correlation Coefficient

A simple statistical test examining the relationship between 2 sets of data.

95% significance: 0.377       99% significance: 0.534

For % of vegetation cover: +0.41 so there is a 95% certainty that it and distance from the sea are related.

For number of plant species: +0.47 so there is a 95% certainty but is more than vegetation cover

There is a moderate positive correlation.

Given that we had had 20 sites we can say with certainty that there is a 95% correlation between the variables. We can't be 99% sure.

Advantages:

  • Tells whether direction of relationship is positive or negative
  • Tells exactly the strength of the relationship unlike the scattergraph which only gives a general indication

Disadvantages:

  • Correlation does not equal causation
  • Simplistic technique
  • Need at least 10 sets of data

Fieldwork: Scattergraph

A scattergraph of distance from sea against percentage plant cover.

Dependent Variable: % of Vegetation cover
Independent variable: Distance from the sea (the one we changed)

Positives:

  • Shows the 'direction' of a relationship between 2 sets of variables through the line of best fit
  • Indicates strength of correlation by how close the points are to the line of best fit
  • Simple and visual representation of correlation
  • Shows anomalies

Negatives:

  • Have to subjectively assess the strength and correlation of the relationship
  • Individual sites are hard to identify
Ideally we would use it in conjunction with a spearmans rank.

Our results so show a positive relationship so vegetation does seem to increase but it is a fairly weak relationship as there are lots of anomalies.

Fieldwork: Improving Reliability

In order to improve the overall reliability of our results, reduce the impact of anomalies and strengthen our conclusions we could have:

  1. Repeat our experiments at another time - the environment changes throughout the year
  2. Other samples would mean a more valid conclusion
  3. We could have visited other sand dunes to compare - otherwise our conclusions are just about Studland Bay Sand Dunes and they might be anomalous
  4. Do more transects or spread them further apart to come to genuine conclusions about the sand dunes
Braunton Burrows, Devon:

would reduce the impact of anomalies and increase our results validity.

Fieldwork: Interrupted Line Transect


We did an interrupted line transect across the sand dunes every 10m.

Appropriate?

Yes

  • We were looking for changes between the sea and trees, so it was appropriate for our hypothesis.
  • If we had done random sampling all 20 sites might have been in the same place and we wouldn't have observed change with distance



Fieldwork: Systematic Sampling


We sampled slope angle, vegetation, wind speed and temperature every 10 metres.

Advantages:

  • It meant every area of the dune was sampled - we could see that trend changes with distance


Disadvantages:

  • Most of the sand dunes are missed out because we only sampled every 10m
  • We may have picked out a trend in nature - eg underlying limestone might cause chalky soils which only allow some plants to grow - This could give us a false impression
Appropriate Method?

Could have used random sampling and put numbers 1 - 200 in a hat to decide where to do our measurements.
BUT in order for it to be truly random we would have to put the numbers back, and all the places we picked out might be the same place 20 times which wouldn't give us an appropriate picture


Fieldwork: Quadrat


To assess vegetation changes we used a Quadrat. It had 25 squares (each square was 4%), and we placed it on the ground every 10 metres (systematic sampling). We estimated the total vegetation cover as well as the number of species, which was vital to our hypothesis.

Advantages:

  • Gives consistent/closed area to analyse
  • Helps estimate percentages

Problems:

  • Can crush/squash larger vegetation like marram grass
  • Percentages were a crude guess
  • Some species might have been misidentified or obscured
  • Might have missed out some vegetation that grows in clumps
  • Mights have missed out some species eg trees

Friday 10 May 2013

Population Change in LEDCS

LEDCS tend to:

  • Have higher birth rates in Stages 1 and 2 of the demographic transition model
  • Have a steeper fall
  • Have a larger base population
  • Once they reach stage 3 the fall tends to be much steeper
  • Population change is more linked to stronger government intervention than economic benefit


Case Study: Thailand

  • National Family Planning programme since 1970
  • Advertising the benefits to a two child family
  • Establishing health care centres throughout the country
  • Public information programmes about contraception methods
  • Training parademics and midwives from local villages who are known and trusted


Case Study: Corfe Castle Services

















Friday 3 May 2013

Case Study: British American Tobacco

Our goals are to grow our brands and the value of the business, to improve productivity and to embed the principles of corporate responsibility around the Group
Brands They Produce: Dunhill, Kent, Lucky Strike, Pall Mall, Bensons & Hedges etc

They have the dominant market share in: Canada, Australia, Brazil, South Africa, Pakistan, Norway and many more.


Manufacturing:

  • HQ in London
  • R&D in Southampton and Cambridge (university towns)
  • 52 Factories worldwide, plus 4 specific cigar factories

Tobacco Leaf Sourcing: 

  • Purchase 460,000 tonnes of tobacco leaves
  • 80% of the tobacco leaves are from emerging countries
  • The supply chain is made up of around 250,000 farmers
  • Tobacco leaves are produced under a 'Social Responsibilty in tobacco production programme

Global Brands Drive:

  • Trying not to be reliant on just USA and Western Europe as while there are high profit margins there is a decline in sales volume
  • Trying to break into emerging economies where volumes are set to rise like Indonesia, where lots of cheap tobacco is sold until a lot of people are addicted

An ethical approach means that shareholders, consumers and producers are happy. BUT there are some issues...

Developing Economies and Tobacco:

  • Largest agribusiness in Kenya, contracting over 17,000 farmers who work on 15,000 hectares.
  • In these regions food production had dropped dramatically
  • The danger is that tobacco cultivation will replace food crops
  • Tobacco sourced from the devloping world tends to be used to make less expensive brands - cigarrettes made from tobacco grown in Brazil cost half of ones with American tobacco
Developing economies and tobacco: 
  • Shift in production to LEDCs because of their lower labour costs, with many factories in South East Asia
  • Factories in places like Singapore and Kores are closer to destination markets
  • Closure of UK factories like one in Southampton
Marketing and Tobacco:
  • Harder to advertise cigarrettes in MEDCs due to advertising bans
  • Iincreased activity in NIC and LEDC markets as oppose to MEDCs, where it is declining in part due to health/social issues
BAT in India:

  • It is an emerging market
  • Around 5 million children under the age of 15 are addicted to tobacco
  • BAT are actively advertising to convert people, particularly the young, to cigarettes eg branded pop concerts, free samples
  • TNCs can now own factories outright in India


http://www.bat.com/

Tobacco TNCs

Brands: Camels, Malboro, Prince, More, Mayfair
TNCs: Phillip Morris International, China National Tobacco, Japan Tobacco International

(Not so fun) Facts:

  • 5 trillion cigarettes are produced per year globally
  • Tobacco is smoked by over 1 billion customers around the world every day
  • Around 6 million people die globally each year from smoking
  • Globally there are between 8,00 to 14,000 cigarettes produced every minute

CHINA:
China is the biggest market with 350 million smokers consuming 1800 billion cigarettes each year.

It accounts for 35% of the global market.

70% of chinese men smoke, but only 4% of women.

The industry in China is owned by the State.

The Chinese National Tobacco Company was worth $91.7 billion in 2010.

The Health Risks of Smoking:

  • Heart attacks and strokes - Smokers are 5x more likely to have a heart attack than non smokers
  • Cancer - Oral, throat, lung, cervical
  • Other lung problems like Emphysema

Sunday 21 April 2013

Formation of Wave Cut Platforms


High and steep waves crash into the foot of the cliff, focusing their erosive capabilities into a small area.

A wave cut notch is created by undercutting the cliff:
Continual undercutting causes increased stress and tension in the cliff which eventually collapses.

Rock debris collects at the foot of the cliff and forms a terrace which is eventually moved into deeper water by backswash or along the beach by longshore drift.

The cliffs continue to retreat leaving behind a gently sloping (less than 5 degrees) wave cut platform.

This means that the waves break further out to sea and have to travel across more platform before reaching the cliff line.

This leads to a greater dissipation of wave energy which reduces the rate of erosion of the headland which slows the growth of the wave cut platform.

Saturday 20 April 2013

Managing Coastal Environments: Shoreline Management Plans

have been developed by local councils and the environment agency, adopting a more holistic approach.

Coastal defence authorities can't carry out works without the aid of a shoreline management plan.

Tend to include:

  1. Hold the Line - maintain/upgrade the level of protection provided by the existing coastal defences
  2. Advance the line - Build new defences seaward of the existing defence line
  3. Managed Realignment - allow retreat of the shoreline inland with management to control or limit that movement
  4. No active Intervention - a decision not to invest in providing or maintaining defences
Sustainable Future?
  • Sea levels are predicted to continue to rise approx 6m a year because of global warming
  • Areas of the UK continue to sink because of isostatic uplift, changing at the rate of 2mm a year
  • The use of public money to defend the undefendable is unsustainable
  • A 'do nothing' approach is often the only affordable way in the long term


Sediment Cells

The movement of sand and shingle in the nearshore zone by longshore drift has been found to occur in discrete, functionally separate sediment cells.

There are 11 such cells around England and Wales with smaller sub cells within them eg from The Wash to The Thames.

The main cells are defined as a length of coast and its associated nearshore area within which the movement of coarser sediment is largely self contained.

Interruptions to sediment within one cell should not affect beaches in adjacent cells.

Malthusian population theory

Name: Thomas Malthus
Date: 1798

Main Arguments:

  • Population increases faster than food supply and supporting resources
  • Increasing population could lead to war, famine and disease
  • PREVENTION: Celibacy, delaying marriage and having less children
  • War, famine and disease are good things as they increase mortality
Limitations/Criticisms:
  • Didn't foresee the development of new technology like GM crops
  • Was wrong in assuming that overpopulation was the reason for famine, there are many factors, like war
  • Didn't consider that people would eventually control their birth rates
Case Study:
In 1960 Mauritius had finite island and the fastest growing population in the world.
Most of the land was used to grow sugar, but it was a cash crop that went to MEDCs.

How it was solved:

Family planning meant that fertility rates were halved from 6 children a woman to 3.

Promotion of contraception meant that in 2001 the population was 1.1 million where it would have otherwise been 3 million.

Ester Boserup Population Theory

Name: Ester Boserup
Date: 1965

Main Arguments:

  • Increases in population stimulates the development of technology for things like food production
  • Incentive to modify technology to produce more food
  • "Necessity is the mother of all invention"
  • eg GM crops
Limitations/Criticisms:
  • Things like GM crops are more susceptible to disease
  • GM seeds are more susceptible to drought
  • There was a 27% increase in cancer rates after they were introduced in the Phillipines
Real life examples:
  1. The Phillipines 1966-1986, rice production increased from 3.7 million tonnes to 7.7 million tonnes
  2. 'Green Revolution' the widespread introduction of high yielding seeds, water control and mechanisation, use of fertilizers and pesticides to allow more people to be fed

Friday 19 April 2013

Case Study: US Health system and French Health System

USA: Free market health care provision 
  • Based on the principles of a free market economy
  • Extremely privatised
  • Most care providers are privately run organisations
  • There are a few federal, state, county and city run facilities
  • 65% of hospitals are privately run not-for profit organisations
  • Per Capita expenditure on health was US$6714 in 2006
  • One of the most expensive models in the world
  • Usually provided through health insurance with 64% of the population having some sort of medical insurance plan
  • Insurance is often paid for by employers as part of a salary package - the health insurance alone is around US$10,000 per year to an employee and their family
  • Health insurance companies operate to make a profit
  • Recently introduced some governmental support - all Americans over the age of 65 have access to Medicare
  • Medicaid provides basic state provided health care for the poorest people but not comprehensive cover - 14 million people still have no acces to healthcare
  • Around 15% of the US population (45 million) does not have any health insurance
France
  • Mainly funded by the government 
  • Administrated through a number of social insurance schemes
  • In 2004 80% of the population were covered by the main State regulated insurer
  • Individuals must pay a compulsory health insurance of 0.75% of their earnings which is deducted from their salary
  • Their employer then makes a 12.08% contribution
  • About 85% of the population also pay a voluntary top-up premium of 2.5% of their income to make sure all their health costs are fully reimbursed
  • Recently introduced a system of health coverage CMU so that those earning less than 6600 euros don't have to make any health insurance payments
  • Provided by general physicians
  • No restrictions on where doctors can set up their practises
  • Individuals have the choice of using more than one general physician
  • You can demand access to hospitals and specialist services without a referral from a general physician

Healthcare Systems

Emergent:

  • Healthcare viewed as an item of personal consumption
  • Physician operates as a solo entrepreneur
  • Professional associations are powerful
  • Private ownership of facilities
  • Direct payment of physicians
  • State's role in healthcare is minimal
  • Development of local health workers 
Eg, in India healthcare is highly diversified with both western and traditional practises operating.

Socialised:
  • Healthcare is a state-provided service
  • Physicians are state employed 
  • Professional associations are weak or non existenet
  • Facilities are wholly publicly owned
  • Payments for services are entirely indirect
  • State's role in healthcare is total
Cuba's health service is very effective, with the WHO ranking it just below the USA's despite the fact it spends 10x less. 

1 in 6 doctors in South Africa are Cuban partly because there are 21 medical schools providing free training.

Pluralistic:
  • Healthcare viewed as a consumer product 
  • Physician operates as a solo entrepreneur
  • Professional associations are powerful
  • Private and public ownership of facilities
  • State's role in healthcare is minimal and indirect
In the USA the health system is provided by thousands of independent doctor, clinics and pharmacies however the federal government recently introduced Medicaid and Medicare.

Insurance/social security:
  • Healthcare is an insured and guaranteed consumer product 
  • Physicians operate as social entrepreneurs and as members of strong professional associations
  • Private and public ownership of facilities
  • Payment for services mostly indirect
  • State's role in healthcare is evident but indirect
WHO judged the French healthcare system to be the most effective in the world, but it also very expensive accounting for 10% of France's GDP.

National Health Service:
  • Healthcare is a state supported service
  • Physicians operate as solo entrepreneurs and as members  
  • Facilities are mainly publicly owned 
  • State's role in healthcare is central and direct
The only countries with national health care are the UK and Canada. Canada's aim is to provide its citizens with equal access to healthcare regardless of their ability to pay in a scheme known as Medicare.


Thursday 18 April 2013

Helicoidal Flow

Helicoidal Flow is the cork-screw like flow of water in a meander.

It is a contributing factor to the formation of sli off slpoes and river cliffs in a meandering section of river. The helicoidal motion of the flow aids the processes of hydraulic action and corrasion on the outside of the meander, and sweeps sediment across the floor of the meander towards the its inside.

The Genesis of a Meander

Pools are are areas of deeper calmer water with greater erosion and where the river flows faster due to reduced friction.
Meandering River Wharfe

Riffles are wide shallow areas of the river where water 'ripples' over pebbles beds with protruding rocks.

As these pools and riffles enlarge, the river will be propelled by centripedal force to twist round the riffles thus starting the side to side flow of the river. Erosion occurs on the outside of the bend, while deposition occurs on the inside.

All rivers take the path of least resistance to maintain theire maximum velocity (thalweg).

Outside of the bend:

  • Fastest flow
  • Lateral erosion
  • Hydraulic action
  • Undercutting of the alluvial materials of the river's floodplain
  • Abrasion
  • Deeper
  • River cliff

Inside of the bend:

  • Deposition
  • Shallow
  • Slowest flow
  • Slip off slope/point bar
  • Low energy

Monday 15 April 2013

The Demographic Transition Model


Stage 1: High Fluctuating, eg Zimbabwe

Reasons for High Birth Rate:

  1. High infant mortality rate
  2. In some cultures children are a sign of fertility
  3. Limited birth control/family planning
  4. Future source of income

Reasons for High Death Rate:

  1. Poor levels of hygiene facilitates the spread of disease
  2. Not much food surplus, famine
  3. Inadequate health facilities

Stage 2: Early Expanding eg Uganda

Reasons for falling death rate:

  1. Industrialisation generates wealth leading to an improvement in public health
  2. Increase in personal wealth means better nutrition
  3. Improvement in public health facilities and widening access to healthcare, often leading to a decrease in child mortality rates

Stage 3: Late Expanding eg China

Reasons for a falling birth rate:

  1. Increasing personal wealth leads to a change in social trends and fashions followed by a rise in materialism
  2. Better access to family planning
  3. Compulsory schooling makes children more expensive
  4. Improved access to health and sanitation facilities leads to a lower infant mortality rate
  5. Greater access to education for women and later marriages leads to a preference for smaller families


Stage 4: Low Fluctuating eg Japan

Reasons for fluctuations in Birth/Death rate:

  1. Increase in lifestyle diseases from low excersize and fatty foods
  2. Groth of and acceptance of childlessness
  3. Growth of individualism linked to women working
  4. Greater financial independence of women
  5. Concern for the impact an increased population has on the world's resources
  6. Breakout of relatively new epidemics/pandemics eg AIDs

Stage 5: Decline eg Germany