geography snapshot notes dynpl
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Geography Snapshot Notes (DynPl)
Dynamic Planet
Restless Earth
Tectonic PlatesThe Earths Structure and tectonic movement
The earths core is 5000c these high temperatures are caused byradioactive decay
The heat given off by the earths core causes convection currents in themantle and these convection currents drive plate motion
Inner and Outer core made up of iron and nickel Mantle is semi-molten rock more solid near the top Crust is made up of tectonic plates oceanic and continental
Magnetic Field Protects us from harmful radiation and particles in the solar winds they would destroy all living things and
burn us
It also helps us navigate The solar winds get destroyed by the magnetic field around the earth it blocks the solar winds from
reaching the earth
A reason for the magnetic field is because of the convection currents in the outer core which is made byiron and nickel these convection currents create electrical and magnetic fields
Plate Boundaries
Constructive plate boundary
Plates get pulled away from each other caused by convectioncurrents moving in the opposite direction
When the plates move apart the magma spills out from underneath(lava is runny and not explosive)
When the lava cools it creates new land e.g. the Atlantic mid-oceanridge
Causes shield volcanosDestructive plate boundary
Collision Margino Continental and continental drive into each othero The crusts causes the land to buckle upwards causing fold
mountains (the Himalayas)
o One of the plates gets forced underneatho Causes earthquakes
Destructive margino Ocean and ocean or Ocean and continentalo One of the plates gets forced under and the carbon in
the crust gets heated and CO2 gets formedo The pressure, because the CO2 gas needs to escape builds
up and causes an earthquake and composite volcano
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o The subduction zone is the area where the one plate gets forced underneath the other plateo Where the oceanic plate goes under there are ocean trenches
Conservative Plate Margin
Two plates moving in different directions or the same direction butat different speeds passed each other
The plates get jammed as they move pass each other building upextreme tension
When they move pass each other it causes big earthquakes (SanAndreas fault line)
Major tectonic plates
Volcanos and Earthquakes
Volcanos
Mainly situated around the pacific ocean and the Ring of FireShield Volcano
Caused by constructive plate boundaries Basalt magma which is sticky and runny The runny lava can travel long distances before cooling producing large gentle slopes Low gas content in lava meaning little or no explosions Low in silica allowing easy flow
Composite/Dome Volcano
Caused at destructive plate boundary High silica content means it flows less easily leading to steep sided volcanos Gasses trapped in the magma leads to lots of explosions Molten lava a pyroclastic material thrown out of the volcano in the explosion
Why are volcanos important?
They create new land when the lava melts The ash from the ash clouds put nutrients into soil making it very fertile
Reducing impacts of Volcanos
Prediction Technologyo
Monitor tell-tale signs like escaping gas and the shape of a volcanoo Gives time to evacuate
Building Techniqueso Designed to withstand pyroclastic and lava flows strengthened so withstand hot ash
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o Barriers divert lava awayo All this reduces unemployment after the volcano
Placement planningo Avoiding risk areas and using fire breakso Emergency service planning and prepo Evacuation routes
Educationo Training on reaction and evacuationo Survival kits
Sending aid to help outCASE STUDIES:
MONTSERRAT (LEDC)
WHAT: Composite volcano WHERE: Montserrat, 25.06.1997 SOCIAL IMPACT:
o 19 people died (P)o schools and buildings destroyed (P)o 8 12,000 left population decline by 66% (S)o 20 villages destroyed by pyroclasic flow (P)
ENVIRONMENTAL IMPACT:o 4km2 covered in lavao Many villages covered in ash (P)o Crops destroyed (P) however soil fertility improved in long run (S)
ECONOMIC IMPACT:o Tourists stayed away and economy declined (S)o UK 41 million to rebuild and mitigate short term impacts
Response:o People evacuated and shelters were builto 17 million sent in initial aid by UK - 41 mill in totalo Local emergency serviceso Montserrat volcano observatory set up to predict future eruptions
St Helen Volcano (MEDC)
WHAT: Composite volcano WHERE: USA Washington State , 07.2005 SOCIAL IMPACT:
o 63 people died (P)o People lost jobs (S)o Flooding destroyed communications such as roads and railway bridges (S)
ENVIRONMENTAL IMPACT:o Hot ash destroyed forests (P) soil fertility improved (S)o Ash blocked rivers (P) destroying fishing and causing flooding which destroyed crops and livestock
(S)
ECONOMIC IMPACT:o Re- Housing for homelesso Re-building bridgeso Increased tourism
Response:o People evacuated and shelters were built
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o 17 million sent in initial aid by UK - 41 mill in totalo Local emergency serviceso Montserrat volcano observatory set up to predict future eruptions
Earthquakes
Weak Shallow Earthquakes
Produced with constructive boundariesStrong shallow Earthquakes
Destructive plate boundariesStrong Deep Earthquakes
Destructive plate boundaries Conservative plate boundaries
Reducing impacts of Earthquakes
Prediction no technology or sure way of knowingo Clues: like animal behaviour and small tremors
Building Techniqueso Reinforced concreteo Special foundations (rubber shock absorbers)o Pendulum on very large buildings to move with earthquakeo Cross bracing for more flexibility
Placement planningo Previous earthquakes can help predict future oneso Fire breaks can be put in to reduce the spread of fireo Planned evacuation routes and procedures
Educationo Training for emergency services and peopleo Survival kits
Sending aid to help outCASE STUDIES
SICHUAN (LEDC)
WHAT: Collision Margin, 7.9 on Richter scale Indian and Eurasian plate WHERE: Himalayas, 12.05.2008 SOCIAL IMPACT:
o 70,000 people died (P)o 375,000 injured (P)o 7,000 schools destroyed (P)o 4.8 million Homeless (S) (80% of homes destroyed (P))o 169 hospitals collapse (P)o Communication destroyed (S)
ENVIRONMENTAL IMPACT:o 2 chemical factories collapsed (P)o Dams burst (P)o Landslides blocked rivers (S)
ECONOMIC IMPACT:o $150 billion to rebuild (S)o 1.4 million lose jobs (S)
Response:
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o Emergency couldnt reach for 30 hourso 3.3 million tentso International aid neededo Troops brought ino Government aid neededo Aimed to rebuild in 3 years
ITALY (MEDC) WHAT: Collision Margin, 6.3 on Richter scale WHERE: Italy, 6.04.2009 SOCIAL IMPACT:
o 290 people died (P)o 1,000s buildings destroyed (P)o Bridge collapsed (P)o Water pipe broke (P)o Many homeless (S)o Fires caused by broken electrics (S)
ENVIRONMENTAL IMPACT:o Broken water pipe caused landslide (S)
ECONOMIC IMPACT:o $15 billion to rebuild (S)o Whole town had to be rebuilt
Response:o After shocks made rescue difficult (S)o Camps set up for homelesso Rescue services and diggers to clear rubble and save peopleo Government aid neededo Investigated why buildings werent built to withstand earthquakes
Climate Change
How has climate changed in the past?
Climate Change: Any long term trend or shift in climate Short term climate change: Last few decades Medium term/Historical climate change: Last few thousand years Long term/geological climate change: Hundreds of thousands or millions of years ago
Climatologists
Confident about past climate change by looking at evidence like:o Ice coreso Fossilised plants and animalso Polleno Landforms e.g. U-shaped valleys
Medieval Warm Period (Historical Climate Change) 900-1400
Before little ice age Peak in 1150 around 0.25 degree rise in temperature Very good for crops Increased life expectancy
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Little Ice Age (Historical Climate Change) 1500-1850
Peak around 1630 with a 0.25 degree temperature drop Precipitation increased and Winters were longer and harsher Rivers and seas froze Iceland lost half its population Crops destroyed because of cold conditions and livestock died
o Farmers abandoned farms and falls in harvesto Led to starvation
People died of coldo Wet and cold weather caused more disease e.g. Black Death
Tree growth stunted Evidence from drawings, newspapers, diaries and records Ships and trading overseas increased and became more advanced People enjoyed ice skating on the Thames
Changes of Climate in the Past
Pleistocene (Last major cold period)o 1.8 million years ago
Halocene (Warmer period since) Both these periods part of the quaternary period of the earths history
Why did the Megafauna go extinct?
Most recent major climate change was the extinction of the megafauna at the end of the last ice age At the end animals began to migrate North, fighting for food and spaceFood chains disrupted and food
shortage
Caused the megafauna to die outCauses of Climate Change
Natural causes
VolcanosEruption Theoryo Ash and Sulphur dioxide blanket the Stratosphereo This stops sunlight reaching the earth and causes cooling on earth
Changes in solar activityThe Sunspot Theoryo More sunspots means higher amount of solar activityo Warms the earth
Orbital ChangesThe Orbital Theoryo Over a very long time orbit of earth can slightly changeo
This effects our distance from the sun
Human Causes
CO2 emissions and other greenhouseemissions/ pollution
Ozone layer damage Deforestation
Greenhouse Effect
Earth emits greenhouse gases througho CO2 (89% of GHG): factory and cars -
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o Methane (7% of GHG but 21% more powerful than CO2): Landfill sites, gas pipeline leaks, cattleand rice farming
o Water vapour/ dust particles: Cars, planes and factories etc.o Nitrous oxide (3% of GHG but 250 times more powerful than CO2): Aircraft, cars and lorries,
fertilisers and incinerators etc.
o Halocarbons: Solvents and cooking equipment They rise and as it gets thicker it traps more and more heat China USA and Russia all produce lots of CO2 Deforestation reduces the absorption of CO2
Evidence for the Greenhouse effect
Before the 18th century there was barely any CO2 emissions Populations were smaller Industrial revolution led to its rise 20th and 21st century has seen a dramatic increase because of cars, technology and oil In MEDCs have caused the most problems as they use a lot of fuels Strong reliance of fossil fuelsdoesnt seem possible to go back
Amounts of Rising Greenhouse Gases
CO2 risingo From 1800-1900 8% rise (300 parts/million)o 1900-1950 8% riseo 1950 2010 15% rise
Nitrous Oxide risingo From 1800-1900 6% rise (290 parts/million)o 1900-1940 3% riseo 1940 1980 10% rise wood burning fires and smoke/ soot etc.o 1980 2010 levelling off
Predictions of the future
Scientists create models based on a range of scenarios The majority have a bleak output Estimate that temperatures will rise between 1.1 and 6.4 degrees by 2100 Sea levels will rise by 30cm 1m by 2100 (due to melting glaciers)
Impacts and Causes of Climate Change
Social:o
Richer countries who are responsible - less affected than the poorer countrieso Richer countries need to be more responsible and reverse global warmingo Wont be able to grow as much food in some areas lead to malnutrition and starvationo Migration to less extreme climates overcrowding in some areas
Economics:o Fossil fuels are finite cheaper than renewables source of income for richer countrieso Richer countries will be effected most by move to renewableso Serious flood defences would have to be put in place to survive e.g. in low lying cities like London
and NYC
o In LEDCs because of heavy reliance on farming etc. flooding will destroy income and jobs Environmental:
o Sea levels rise as arctic meltso Ecosystems affected and animals become extincto Distribution of species will change
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Political impacts:o Competition for water could lead to war etc.o Increased immigration and emigrationo Pressure on Governments to change
CASE STUDIES:
UK impacts of Climate change
ECONOMICo Farmers grow new crops in the warmer climate e.g. Oliveso More money spent on dealing with extreme weather conditions households are estimated to have
to pay 4% more
o Estimated 1% rise for householders to reduce emissionso Tourism would increase (especially in coastal areas)o New businesses increasing like air conditional
SOCIALo Diseases that didnt exist in UK would become more common e.g. Malariao
Fewer cold related deaths but could have heat related issues ENVIRONMENTAL
o Sea level rising would cause more floodingo Threaten coastal habitatso Some species may not adapt to temperature rise and rainfallo New species distribution of species change
POLITICALo Govt. set up new department to deal with environment etc. Department for energy and climate
change
o External unrest from other countries less land as flooding increases conflict for lando Migration from other countries because countries being lost underwater
Change so faro Coastal waters warmed by 0.7C in 70 yearso Sea levels in 10cm higher since 1900o Rainfall increased increase flooding damage 1bn so faro Holden already experiencing serious flooding
Bangladesh Impacts of climate change
ECONOMICo Economically a very poor countrycant afford flood protectiono 80% of country relies on agriculture loss of many jobs and income lead to even poorer country
SOCIALo 9% of population will be affected by floodingo Destruction of homes, livestock and buildings by floodingo Starvation due to destroyed crops and farmso Strained water supply because of less fresh watero More disease as there will be less clean watero High population density means impact of extreme conditions would be higher
ENVIRONMENTALo Sea level rise by 1m flood 18% of the country as 90% of country is less than 10m above sea levelo More extreme weather cyclones etc. and loss of life
Change so faro Already have serious problems with flooding people being washed away etc.
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Battle for the Biosphere
Key Terms
Biome A community of plants and animals that exist in a similar
climate e.g. Rainforest, Tundra or coral reef
Biosphere Part of the earth and its atmosphere where living
systems exist capable of supporting life
Permafrost Permanently frosty, semi frozen ground
Relief Shape of the land
Altitude Height of land
Sustainable management Act environmentally towards an ecosystem by
conserving it for future generation ensuring it is not
being used up faster than it is being renewed however
ensuring locals have enough resources and jobs
World Biomes
Tundra cold and dry Northern permafrost Boreal Forests/Northern conifer forestscold forests,
pine trees (like Christmas trees!)
Temperate Deciduous and temperate rainforest Clearseasons and plants drop their leaves (deciduous) cool,
medium wet (rainforest is very wet)
Temperate Grasslands Huge grassland e.g. Prairies ofNorth America (Mid Northern) cooler
Mediterranean Scrub ForestHarsher forest/dry andsparse (e.g. Spain)
Deserts Dry, arid and hot in the day and cold at
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night(Mid e.g. North Africa)
Mountainsmountainous areas, e.g. Himalayas Tropical Scrub ForestHarsher forest/sparse, hot and slightly wet Tropical Grassland and SavannaHighly fertile land (e.g. Most of Africa) cool and slightly wet Tropical Deciduous Forest near coasts in the south, hot and wet Tropical Rainforest lies along the equator, rainy and highly fertile lots of plants, very hot and very wet Snow, ice and glaciers southern ice deserts
Local Factors on Biome Distribution
Altitudeo Height of land has impact of climate the higher the land the lower the temperature stunts plant
growth temperature decreases by 1C for every 100m in height
Reliefo Slopes that face the sun will be warmerAspect Reliefo E.g. Warm wet air rises from the ocean, up a slope will rain on one side of the slope but not on the
other (Cause a rain shadow)
Ocean Currentso Current of warm water creates a relatively warmer climate than other areas on the same latitude
Thermohaline Circulation
o Colder currents of water will lead to colder climates on the same latitude Continentally
o Sea heats up slowly and cools down slowly land in the middle of sea then the climate will becold/hot with more rain
o Land heats up quickly and cools down quickly - landlocked countries will have warmer/cold climateswith less rain
Prevailing windso Northern winds are coldo Southern winds warmo Wind travelling over water will be wet and rainyo Wind travelling over land will bring dust and dirto Where your area gets wind from will affect climate
Unusual Biomes
Alpinemainly in Northern Indiao Where it should be very hot as it is near the equatoro Because of Mountains and high altitude it is very cold
Value of Ecosystems
Natural Values of plants and vegetation
Plants and vegetation remove CO2 from the atmosphere and give out oxygen Help us get over the negative impacts of global warming- remove greenhouse gases Trees, forests and vegetation protect soil erosion from water
o 1. Reduce flooding by taking in watero 2. They trap soil and keep it in place
Regulate the Hydrological Cycle Plants and Vegetation put nutrients back into the soil help new plants grow
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Hydrological Cycle
Carbon Stores
We release the carbon stores by:o Global warming heating the oceano Burning oil and gaseso Cutting down treeso Mining for stone
Goods and Services of Ecosystems
Goods
Fish, meat, food and fibre crops (clothing) Timber and rubber Fuel mass and biomass for energy Fruits, nuts and medicines Water for drinking and irrigation Gene pool
Services
Food web and ecosystems Water regulation Atmospheric gas balance and climatic regulation (carbon cycle) Employment and recreation Nutrient recycling
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Genetic resources for future generation (genetic cycle)CASE STUDY: Kombai People of Papua New Guinea (Using the TRF)
Foodo Pigs, bats and cannibalism (not often)o Sagho starch that is dried by fire and the maggots that feed on rotted sagho (Sahgo is a big tree with
soft wood)
Shelter
o They live in isolated tree houseso Never stray from own territory
Heatingo Fire
Cookingo Wrap in leaves and cook in hot stones
Moneyo They use pigs for trade
Utensilso Bamboo as kniveso Stones and twigs for fireo Dogs to help them look for pigs
CASE STUDY: Tropical Rainforest - Goods and Services
Social/ Medicinalo Provides many of Western foods e.g. Pineapple, coffeeo 25% of all cancer drugs are plants from the rainforestso Plants used in contraceptive pillo Drugs to help diabeteso Periwinkle drug improves survival chance of child Leukaemia (moved from 10 to 90%)o Illegal Drugs created in the rainforest
Economicalo Raw materials provide many commodities like rubber and timbero Tourism is popular in the Rainforest
Environmentalo Home to 25% of worlds biodiversity in rainforesto Many indigenous people with traditions
Systemso Regulates Hydrological cycleo Huge carbon storeo Nutrients for the soil
Impacts we are having on TRF (Deforestation)o Fish
Because of deforestation there have been droughts and water levels have been low Fish are being washed into shore dead because of low oxygen levels
o Dolphins Effects of fish dying on food chain Dolphins then dying because they have no food
o Increase in Vultures Because of dead fish
o Fishermen Loss of income low water cannot get to sea and hard for them to find fresh water
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How are we ruining Ecosystems?
Deforestation
Big companies buy large areas of land for cattle, timber, crop growing and rubber (TRF) Locals also use land for similar reasons No Interception of water
o leads to soil erosion and floodingo
Nutrients get washed out of soilo Little filtration of water more surface runoffo Landslides can occur as roots dont hold soil together
No transpiration from leaves not releasing water back into atmosphereo Little evaporation and cloud formationo Can lead to creating deserts as no rain or clouds
Loss of habitat for animals Loss of drinking water as water becomes muddy and unusable
Mining and Drilling
Mining and drilling for oil causes surface damage
Oil produces pollution Mining disrupts ecosystems and tourism
Over harvesting and over fishing
Causes changes in the food chainConserving the Biosphere
Decisions around conserving the biosphere
Balancing:o Costo Difficultyo Importanceo Rarity
Conservation Organisations (CASE STUDIES)
Scale
Global (CITES) National (UK National Parks) Local (BAPs in the UK)
Aims
Protection and conservation (e.g. National parks) Preventing exploitation (CITES)
CITES (Convention on International Trade and Endangered Species) Global Scale
Signed in 1973 Lists endangered species AIM: To prevent trade of endangered species e.g. crocodile skin and ivory etc. However: Global measures are difficult to manage as lots of convicting interests
UNESCO (United Nations Educational, Scientific and Cultural Organisation) Global Scale
World heritage site that lists buildings Aim: Prevent exploitation of important and historical landmarks
Happening
in the
Rainforest
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Ramsar Convention Global Scale
Habitat conservation and protection of wildlife Aim: Protection of habitats globally
UK National Park (ANPA) National Scale
Conserves the UKs 14 national parks AIM: High protection on a national level of habitats
BAPs (Biodiversity Action Plans) Local scale
Aim: Local plans to protect and replace vegetation e.g. tree plantingSustainable Conservation of Biospheres (CASE STUDIES)
1. Selective Loggingo Only some trees are felled mainly oldesto They do it in different areas selectively only a few trees are taken from each area so that alrge ares
arent cleared
o Remove logs by using helicopters of horsesso big trucks dont have to come through and ruin 2. Afforestation
o Replant same varieties of trees after they cut them downo In Costa Rica this is now a law
3. Reduce demand for hard woodo Heavy taxing on hard woods as it takes long to grow and is running outo Discouraging the use of some hard woods some countries banned it
4. Educationo Trying to educate the local people as some dont understand how to be sustainableo Showing them alternative ways to make money like ecotourismo International education to reduce demand on TRF
3 additional ways of reducing deforestation of rainforest
o 1. Eco tourismo 2. Reducing debtso they dont have to make money on the rainforesto 3. Protection passing laws to ban logging. Setting up national parks
Water World
Describe the distribution of water on the earth
97% of water in oceans 2% in glaciers 0.7% groundwater 0.1% in lakes 0.0005% in soil 0.0001% in rivers 0.0004% in organisms
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Hydrological Cycle
Closed cycle amount of water is always the same Process:
o 1. Evaporation/Transpiration: Water evaporated from sea or land when heated by the sun, ortranspires from plants
o 2. Movement: Wind moves water vapour inlando 3. Condensation: Water vapour condenses to form cloudso 4. Precipitation: Falls over land through precipitationo 5. Movement of water: Transfer stages belowo 6. Storage: Storage stages belowo 7. Return: Return to the ocean through rivers etc.
Key Terms
Areaso Biosphere areas above ground e.g. cloudso Lithosphere ground and undergroundo Ocean
Inputso Precipitation snow, rain etc.
Transfero InfiltrationMovement of water from surface to soil
SaturationWhen the soil cant hold any more soil Water table the level at which saturation occurs in the water or the ground
o Percolation Movement of the water from the soil to the rockso Stem Flow transfer of water through plantso Surface Runoff Surface water runs into the rivero Through Flow Transfer of water through the soil to the rivero Groundwater flow water travelling through aquifers (permeable rock) to the river
Storageo Surface StoragePuddles, lakes, rivers etc.o Groundwater storage underground in rocks and soilo Interception storage in plants from capture on leaves etc.
Outputso EvaporationWater loss from surface storage, sea or groundwatero Transpiration water loss through plants
How humans effect the supply of water
Deforestation increases flood risk and reduces rainfall Over abstraction takes too much water out and leads to dry rivers
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Build too many reservoirs which increases evaporation (through higher surface area to volume ratio)CASE STUDY: Murray Darling Basin in Australia
Murray Darling Basin
39% of national agriculture production 2 million people living in basin
Demands on water Agriculture irrigation for farming Increasing population in Australia Rising living standards water needs to be used for:
o Washingo Drinkingo Gardens etc.
Causes of water shortage
Over abstraction of water Climate change is making droughts worse Freshwater is being polluted North using too much not enough getting to the south
Impacts of water shortage
Farmers and agriculture is suffering River has not met the see for many years River is accumulating pollutants making it unusable Wetlands full of salt freshwater not reaching them Dryness of the area is causing forest fires
Management plans
Using water wisely Support healthy rivers Investing in water infrastructure to make water use more efficient
Human effect on water quality
Salt comes from factories etc. makes water unusable e.g. water cannot be used for farming and kills fishand plants
Fertilisers can lead to eutrophication and water becomes deprived of nutrients and oxygen Toxic waste (like chemicals, pesticides, cyanide, radiation) in rivers kills fish Domestic waste sewage, toxic chemicals from washing etc. Solids/dirt colour the water and kill fish Thermal Pollution hot water comes out of power stations and reduces oxygen in water killing life
CASE STUDY: River Rhine
Companies along the river emptied waste, salt and toxic substances into river Households put sewage and household chemicals in the river Agriculture dumped fertilisers and chemicals in water
Impacts
Public health affect with impure water Polluted water was useless Fish were dying
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1986 chemical fire
Fire in a chemical plant Thousands of tons of waste went into the river Millions of fish and wildlife were killed
Action: Rhine Action programme
They improved water quality
Salmon returned to the Rhine 50% reduction in pollution
Water Management Schemes
Large Management schemes: DAMS
Pros:o Increased water supplyo Money generated from selling water good for economyo HEP createdo Recreation fishing, sailing and swimming
Cons:o Land and habitat losso Relocation
CASE STUDY: Lesotho Dam
Social:o PROS:
Built new clinics and schools with the income from the dam Short term jobs were created to build the dam
o CONS: 300 homes lost through flooding Farmland was lost hard for uneducated farmers to get new jobs
Economical:o PROS
35,000-40,000 short term jobs created $40 million a year from selling the water
o Cons Project cost $18bn 4,000 hectares of grazing land lost
Environmental:
o Pros: Environmental education and soil erosion control plans have been paid for by the scheme
o Cons: Dam induced seismic activitycausing cracks in the earths surface Loss of wood as a source of fuel Soil becomes saturated underneath the dam will never be able to be used again
Small scale water management
Generally set up by no-governmental organisations in LEDCs
Bottom up approaches Low cost using intermediate technology Appropriate for locals and environment Self-sustaining people trained and educated to use the small methods
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CASE STUDY: Water Aid charity
Rain water Harvesting
Falling water (rain) is the cleanest Generally collected from pre-cleaned roofs Runs from roofs into a storage tank
Hand Dug wells
Ground water safe to drink as fine layers of the earth act as filters for bacteria and other impurities Digs deeper wells so they get to the water table even in dry season Porous walls made out of concrete to allow water to get in They are lined semi-permeable lining to stop pollutants getting through The top is raised and covered to stop surface water polluting it
Tube Wells and bore holes
Small diameter hole drilled with hand powered methods (Tube Wells) Quick and cheaper to build and require less maintenance than hand dug wells Can reach greater depths However: you need equipment and where there are rock it is hard In areas where there is lots of rocks or little water (need more depth) machinery is needed (Bore holes) Hand pump or electric pump to bring up the water Storage in lined tanks
Coastal Change and Conflict
Key Terms
Coastal Zone system Area where land meets the sea constantly changing
Crest Top of wave
Trough Bottom of waveWavelength Distance between two crests
Wave height Distance between crest and trough
Constructive waves Build up beaches
Destructive waves Take from beaches
Swash The wave as it goes onto the beach goes in the
direction of the wind
Backwash As the wave comes back again away from the beach
always at right angles
Fetch Distance over the which the wind has blown on a wave
bigger fetch means a more energetic wave
Long shore drift The movement of waves as it transports material alongthe beach
Concordant A cliff that runs parallel with the coast
Discordant A cliff that runs away from the coast of perpendicular to
the coast
Weathering Disintegration of the earths surface in situations
Mass movement Landslides and landslips large scale movement
Erosion The process of being worn down by wind, water or other
natural agents
Wave cut notch The undercut at the bottom of a cliff where it has been
eroded away by wave action
Wave cut platform Top bit of the cliff that has collapsed and leaves debris at
the bottom of the cliff
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Wave Refraction As the waves reach the coast, the waves tend to bend
and mirror the coastline like at headlands and bays
Coastal System
Inputso Windo Waveso Tides
Processeso Weatheringo Erosiono Transportationo Deposition
Outputo Landforms
Erosional landforms (bays and headlands, cliffs and arches etc.) Depositional Landforms (beaches, dunes and spits etc.)
Waves
Constructive waveso More swash than backwasho Deposit things on the beach more than they take from the beacho Long wavelength and shallow gradiento Steep beaches
Destructive waveso More backwash than swasho Tall waves with a short wavelengtho Smooth beaches
Wave Refractiono As the waves reach the coast, the waves tend to bend and mirror the coastline like at headlands
and bays
Wave action how does it work?
Breaking waves:
o Bottom of wave slows as it touches the sand due to friction on sea bedo Wavelength decreases but the top keeps toppling so wave height increaseso The top topples over and breaks wave breaks
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Wave energy depends on the fetchthe longer the wind has worked over the wave, the more energy it has the fetch is the distance over which the wind has blown a wave
Swash The wave as it goes onto the beach goes in the
direction of the wind
Backwash As the wave comes back again away from the beach
always at right angles
Fetch Distance over the which the wind has blown on a wave
bigger fetch means a more energetic waveLong shore drift The movement of waves as it transports material along
the beach
Rocks and Landforms on a coast
Hard Rock
Leads to high, steep and rugged cliffs The cliff face is often bear with no vegetation or loose rock At the cliff foot there are a few boulders or rocks that have fallen from cliff An example is Lands End (Cornwall)
Soft Rocks
Could be high cliffs but not as steep or rugged You may see piles of mud and clay that has
slipped down the face of the cliff meaning
vegetation on cliff face
At the cliff foot there will be little or no rocksand boulders but clay deposits and some mud
An example of the is HoldernessCASE STUDY: Dorset Coast line
The Dorset coast line has many different typesof rocks
Area at the top with clay and sand wherePoole harbour and Studland Bay are soft clay
and sand is more eroded and created bays and
harbours
Then it has hard chalk rock which isnt as easily eroded has created Ballard Point (a headland) More clay and sand which makes Swanage Bay Around the South coast is Limestone which is hard and has created Durlston Head
Discordant
Concordant
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Headlands and Bays
Weathering, Erosion and Mass Movement
The processes of weathering and mass movement are called Sub-Ariel because they can happed away fromthe sea
Weathering
Disintegration of the earths surface in situationsTypes of Weathering
Physicalo Like freeze thaw when water get into cracks it freezes and expands causing crackso When it thaws again it leaves ito The cracks get bigger as this happens over and over
Biologicalo Plant roots get into rocks and can slowly pull them apart as they grow causing crackso Animals can also wear away the rocks by burrowing into the ground
Chemical Weatheringo Chemicals like Nitrous oxide mix to form acid with water (acid rain)o These acids pollute and wear away limestone
Erosion
The process of being worn down by wind, water or other natural agents Harder rocks dont get eroded as quickly e.g. granite at Cornwall forms headlands Softer rocks like boulder clay get eroded quickly and form bays e.g. Holderness
Mass Movement
Landslides and landslips large scale movementCliff foot Processes
Waves attack the base of a cliff1. Hydraulic Action
a. As waves crash into the rocks they force air into themb. This air is drawn out again when the waves recedec. This action of air being forced in and out causes cracks
2. Solution and Corrosiona. Weak acids in the water slowly erode some of the rocks
3. Attrition
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a. Waves force little rocks in the sea to smash into each other leaving them smooth4. Abrasion
a. Small bits of rock and sand rub against the cliffb. Over time this wears away the cliff
Over time all of these processes cause a wave cut notch to be formedo This means that the under part of the cliff where the water is gets worn away creating a notch
Eventually the cliff top becomes unstable as it isnt being held up by anything and collapses The cliff then retreats and moves back The debris of the top of the cliff creates a wave cut platform
Formations
Cove
Happens when there is a layer of hard rock on a coast and a layer of soft rock behind it The sea get through a weakness in hard rock and causes a small opening When it gets to the soft rock it erodes it quickly forming a large cove
Headland erosion stacks and stumps
1. Headland2. Cracks form in the headland because of wave action3. Over time the crack expands with further wave action and a cave forms4. As the cave get bigger and deeps, the wave erodes through
the back and forms and archway
5. As the wave act on the archway it widens e.g. Durdle Door6. Eventually the arch gets so wide that the top cannot support
itself and collapses leaving a stack that is no longer joined to
the headland e.g. Old Harry Rocks
7. Waves eventually wear away the stack leaving a stump8. The stump gradually get eroded away and the process starts
again
Beaches
Beaches form in sheltered environments such as bays Has to be constructive ways that deposit beach sediment Sometimes strong winds can blow sand from offshore bars onto the beach and dunes get created
Spits
1. Steady prevailing winds which causes longshore drift2. This collects sand and sediment from a bay, around a
headland
3.
Spits form when, around the headland, there is a riveroutlet travelling in the opposite direction
4. This pushes out the sediment from following theheadland round making the spit curve out
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5. Between the headland and spit salt marshes get formedTombolo
Longshore drift moves sand around a headland The sand connects with an island near the headland This forms a beach between the headland and the island creating a
tombolo
Bar
Longshore drift moves sand around a headland The sand connects with another headland near This forms a beach between the two headlands creating a bar A lagoon forms behind it and gradually will be fill up and both bar
and lagoon will become one beach
Threats of rising sea levels of rapid coastal erosion
CASE STUDY: Easington on Holderness coastline
Rise is sea level is causing rapid erosion
Many holiday homes at Bridlington but no coastal defence so houses can fall in At Easington there is the British Gas terminal 25% of all North Sea gas needs defending as the Gas
terminal is vital
Easington have slowed erosion with rip rap Withernsea has protection with re-curved sea wall and rip rap boulders There is a farm near Mappleton which is in fear of being lost because there is no sand because of the stone
groynes at Mappleton, no sediment is being deposited further down the coast erosion has gone up by a lot
The spit as the end of Humber Estuary has roads that erode away in storms lifeboat operates from there Many people along the coast need protection- but how do you pick who gets it, when protection would
harm other areas further down the coast?
o Conservationists:dont want anything nature should be left aloneo British Gas: wants protection at Easington as gas is vital for the whole countryo Farmers and caravan site owners: wants protection at their coasts as they need to conserve it for
their homes and jobs however putting protection at one coast will have a bad effect on coastsfurther down the coasts
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Coastal Protection
Hard Rock Engineering
Schemes designed to put physical barriers in the way of erosion or flooding Often they interfere with natural processes
Re-curved Sea Walls
Reflect the energy of the wave back to the sea stopping erosion and flooding ADV:
o Very good at dissipating wave energy and reflecting back to see stopping erosion and floodingo Better than flat sea walls that tend to break when waves crash and causes cracks
DisADV:o Can stop access to beacho Looks quite ugly sometimeso Quite expensive
Groynes
Slow long shore drift and allow beach material to build up forming a natural defence along the coast ADV:
o People are used to them so look naturalo They work in building up the beach
DisADV:o Wood groynes can rot and be dangerouso Stone ones can wash awayo Can be quite expensive
Rip Rap
Absorbs energy of the waves from the rocks granite rocks that lie on beach ADV:
o They work well and look natural DisADV:
o Can be washed away and get erodedo Have to be imported and are quite expensiveo Importing them increases carbon footprint
Gabions
Cages of stones placed together in the beach or under the water ADV:
o They are cheapo Work quite wello Dont stop access to the beacho Last quite a long time
DisADV:o Quite uglyo Can be dangerous
Revetments
Sloping features than dissipate the wave energy, can be made from wood or stone ADV:
o They work well in dissipating energy and stopping erosiono Long lasting
DisADV:
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o Can stop access to the beacho Look VERY uglyo Quite expensive
Soft Rock Engineering
Schemes that work with natural processes to build up beachesBeach Replenishment
Beach material is dragged onto the beach to absorb more wave energy and slow down erosion ADV:
o They work in stopping erosion and floodingo Its looks naturalo Quite cheap
DisADV:o Doesnt last very long as long shore drift moves the beach materialo Has to be repeated
Managed Retreat
Allow the land to be flooded that you once were protecting ADV:
o It creates new habitats and salt marshes for animals and plantso It is controlled
DisADV:o You lose the land
Oceans on the Edge
Key terms
Coral Reef Flow of water which might contain nitrated andphosphates picked up from the land and takes them to
the sea
Surface Runoff Deposition of sediment which can choke coral reefs
Siltation Plants and animals in an ecosystem showing the sources
of food for each organism
Food web Structure made up of the external skeletons of polyps
Eutrophication Loss of oxygen in water after too much nutrient
enrichment chemicals, like crop fertiliser, has been put in
the water
Coral Bleaching The loss of zooxanthellae due to changes in conditions
such as temperature. The coral will expel thezooxanthellae causing the coral to go white
Producers Produce food through photosynthesis
Herbivores Eat plant material
Carnivores Eat animals
Omnivores Eat both animals and plant matter
Decomposers Bacteria which cycle organic matter back to nutrients
Locating Coral Ecosystems
Coral occupies 0.2% of the oceans area but it is home to 33% ofthe earths marine life
Mostly found around the equator World Reefs:
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o Caribbean Reefs: 15% of the worlds reefso Pacific Reefs: 25% - including the Great Barrier Reefo Indian Ocean: 60% ofthe worlds reefs
Suffering Reefs: Mini CASE STUDIES
Kenyao Issue: Damage of corals due to tourism and overfishingo
Management: They introduced a national park and have seen a 30% increase in coral cover Thailand
o Issue: Tsunami damaged most of the coral Florida Keys
o Issue: Damaged by tourism they trample and take it. Also damaged by boats that drop heavyanchors on the coral which breaks it.
Jamaican Reefso Issue: Damaged by sewage disposal, agriculture runoff eutrophication, tourism and natural
disasters
Great Barrier Reefo Management: Managed very well without much damage caused to coral
Israel, Jordan and Egypt Reefso Issue: Suffering from coral bleaching as the crown of thorn starfish is eating them however still lots
of coral in that area
Seychelleso Issue: Has lost 90% of coral because of temperature of water going down and overfishingo Management: Taking measures to mitigate effects and coral is coming back slowly
Structure of Coral Reef
Tentacles Soft tissue polypmouthRock like external skeleton made from calcium carbonate whichforms the coral Coral reef is the hard ridge made up of millions of polyp skeletons
Inside the coral lives the zooxanthellae which photosynthesise to produce food for the coral polyp to ear The coral and zooxanthellae havea symbiotic relationship meaning they rely on each other for food and
shelter
Conditions Coral need to survive Temperature of water between: 20 - 30C Shallow seas up to 40m in depth Clear and unpolluted water
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Water with a steady salt contentCoral Food web
ProducersProduce food through photosynthesis Herbivores - Eat plant material CarnivoresEat animals OmnivoresEat both animals and plant matter
Decomposers Bacteria which cycle organic matter back to nutrients
Coral Food Web
If the Reef Shark is hunted then the long nosed butterfly fish wont be in as much threat
If the Long Nosed Butterfly fish isnt in as much threat than there population will grow If their population grow their will be more long nosed butterfly fish eating coral polyps In the end this will lead to a shortage of coral and the long nosed butterfly fish will slowly die out Then the reef shark that are left will have to eat more of its other prey like the Caribbean reef squid The population of the other prey will decrease and have a knock on effect on their food chain There is a problem with the crown of thorns starfish that eat coral there are too many of them because
their predator is overfished
This means the coral reef is being eaten too much and dying outWhy corals are threatened with distinction
Conditions Coral need to survive
Temperature of water between: 20 - 30C Shallow seas up to 40m in depth Clear and unpolluted water Water with a steady salt content If any of these conditions are changed then the coral will be seriously threatened and will die
Natural Causes of Coral damage
Natural disasters like Tsunamiso Tsunamis come in and drag house and building debris back to sea which smashes against the coral
and kill it
Human Causes of Coral damage
Global Warming
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o The water will become hottero The water depth will go up because of glaciers meltingo Glaciers melting will also cause the salt content of the water to go down because glaciers are fresh
water stores
Overfishingo An example of the is the crown of thorns starfish that eat coral there are too many of them
because their predator is overfished
o This means the coral reef is being eaten too much and dying out Trawling and Methods of fishing
o Trawling means that nets full of fish get dragged over the coral and damaging ito Cyanide, another method of fishing, is used to catch large amounts of fish for aquariums the
cyanide is used to stun the fish so that they can be caught alive
The cyanide also poisons the coral Boats
o Boats from fishing and tourists can damage and break coral especially when big heavy anchors aredropped on them
Fertilisers, sewage and Eutrophicationo Farmers use fertilisers and sewage on their farms this gets washed off into the seao The algae in the sea then grows as more nutrients are loaded into the watero Algae competes with the coral for space and lighto It reduces the light so that the zooxanthellae cannot photosynthesise and provide food for the coralo This causes coral bleaching where the zooxanthellae leave due to the change in conditions and
causes the coral to go white
o When the algae die they use up oxygen in the water this means there is less for the fish to respireand they die
o This process of ruining biodiversity with fertilisers and sewage from farms etc. is calledeutrophication
Tourismo Tourists pick up and step on coral which damages ito Sun- cream chemicals can lead to coral bleaching
Increased sediment from deforestationo Blocks sunlightcoral cant photosynthesise causes coral bleachingo Also can crush and damage coral
Goods and Services of Coral Reefs
The coral reef ecosystems are worth up to $200bn a year in terms of the goods and services it provides They are important for tourism and divers, fishing and are a natural form of coastal defence Coral is home to 33% of all marine life and has the same level of biodiversity as he rainforest
Provisioning Services
-foodfish and shellfish
-genetic resources
- natural medicines and pharmaceuticals
-ornamental resources
- building materials
Regulating Services
- carbon storage / climate
regulation
-erosion control
-storm protection
Economical Services
-recreation and ecotourism
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CASE STUDY: St Lucia
Value of the Coral Reefs to St Lucia
Coral reef tourism and recreation (like diving)brings in $160 194mil a year (almost 20% of St
Lucias GDP) and it is considered that 25% of
visitors to St Lucia come for factors related to the
Coral Reefs Coral reef associated fisheries brings in $0.5-
0.8mil a year
The coral also is a natural method of shorelineprotection and saves St Lucia around $28-50mill
a year and 44% of St Lucias coastline is
protected by coral reefs
How are the coral reefs threatened?
Coastal development- causing pollution and corals cannot survive in polluted water
Sewage, sedimentation and deforestation blocking the sunlight coral bleacing Tourism is increasing meaning increasing damage of corals
o Sun-cream use causing coral bleaching Overfishing
o The black spine sea urchin died out - The sea urchin ate the algae and seaweed but as theywerent getting eaten they grew more and blocked out the sunlight causing coral bleaching
and coral damage
Warming Seas (global warming)Management Soufriere Marine Management Area (SMMA)
Marine Reserves/ no go areas
o These reserves have been set aside only scientific research, divers and snorkelers with a specialpurchased permit can go in the areas
o Has allowed marine life to flourish and fish stocks toregenerate
Fishing priority areaso Only fishing is really allowed to go on in these areas
other uses can happen if it doesnt interfere with the
fishermen
Recreational areaso Beaches where tourism and locals can enjoy
recreational activities
Multiple use areaso Can be used by all as long as they are abiding by the
SMMA rules
Yacht Mooring areaso As anchoring is not permitted in the SMMA mooring
areas are provided for yachts
Conflicts
Conservationist vs. Local Fishermeno Conservationist: Want to see reefs protected and bans
on catching important species and a quota for numbers of fish caught
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Problems with this: If too many restriction it could drive up illegal fishing if locals have notalternative
o Fishermen: Only catch enough fish to feed families and sell a little for surplus income Problems with this: Pots and nets used to catch fish damage coral and reduce breeding stock
of fish
Local People vs. Govt.o Locals: 20% of population living below poverty line and 15% are unemployed have to do what they
can to support their families
Problems with this: They do what they can to make an income this including deforestationand damaging fishing methods, like using cyanide which poisons coral
o Govt.: Population is growing by 2% a year need to support them but also need to manageresources sustainably
Problems with this: Due to the mountainous interior of the island, most live in coastal areas putting pressure on coastal ecosystems and resources
CASE STUDY: Firth of Clyde
Pressures on the Firth of Clyde Fishing
o Very important for local incomeo However over-fishing has caused some fish (e.g. cod) to die out
Tourism and leisureo Falling Incomes from fishing have made them turn to tourismo The tourist activities have caused wild life to be disturbed
Sewage disposalo In the past sewage would be flushed straight into the sea and damage wildlifeo Now there are new laws to stop this
Military testingo Testing ground for Royal Navys nuclear submarines a serious accident would devastate the
ecosystem
Scallop Fishing in Lamlash Bay
Much of the Firth of Clyde has been overfished Scallops have been heavily affected they used to thrive in the past The machinery used to scallop has damaged the Maerl, their coral like habitat, which was a home to fish
like cod and haddock
With the Maerl almost gone the fish have gone too.Management in Lamlash Bay
Lamlash Bay has become a No Take Zoneo No fishing from shore or boato No taking of shellfisho Recreational activity allowed (even boating)
In the No Take Zone they are trying to encourage tourist activity as they cant get any money from fishing There is a 5000 penalty fare if rules are broken good deterrent
Conflict at Lamlash Bay
Conservationist vs. Local Fishermen
o Conservationist: Want to see the Maerl protected and the fish thrive Problems with this: If too many restriction it could drive up illegal fishing if locals have not
alternative and could lead to a suffer on the economy
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o Fishermen: Need to fish for a source of income Problems with this: If they overfish there wont be any fish left so a loss of income in the
long term. Also it will affect the biodiversity of the marine life
Management schemes of maintaining and protecting the health of the oceans
Dolphin friendly labelling sets standards for tuna fishing (regional scale)o PROS: protects dolphinso CONS: can lose money for tuna industry and makes tuna more expensive
MSC tick certification Charity set up to find solution to overfishing(regional scale)o PRO: rewards well managed fisheries recognisable label helps solve problems of overfishingo CONS: lost money for fishermen
UNCLOS they control the activity that goes on in the ocean and makes sure its sustainable and 40% of seais under their law (International scale)
o PROS: prevents certain nations from getting unfair share of ocean wealth (protects against whalingand sharking)
o CONS: It is hard to control in some areas and global warming is creating new problems that would behard to stop
International Whaling Commission (IWC)Provides proper conservation of whale stocko PROS: Provides complete protection of some species of whales provides whale sanctuary makes
sure female and child whales are not caught controls number of whales caught
o CONS: bad for whaling industry