1. Causes of Aridity: Cold Ocean Currents
As air masses pass on wind currents, there is an
upwelling of cold ocean water, cooling clouds and
reducing their carrying capacity. This causes what
Extreme Environments little water is left to be precipitated along the
coastline, leaving none for further inland.
Causes of Aridity: Relief
Air masses pick up water from the sea and rise on
prevailing winds, reducing pressure. As it
depressurises, it cools so condensation and
precipitation occur over the mountain range. Dry air
continues to the other side and there is no moisture
left to rain.
Causes of Aridity: Global Atmospheric Circulation
There is an are of low pressure between the Hadley
cells called the inter-tropical convergence zone (ITCZ)
where air will rise and move polewards, sinking
between 20-30▫ North or South in the Hadley cells. It
meets air doing the opposite in the Ferrel cells,
causing a high pressure zone with anticyclonic
conditions, building up heat during the day, picking
up moisture from the area and radiating heat out at
night.
Causes of Aridity: Continentiality
Maritime regions often receive the majority of rain
from evaporated sea water, and with less water
sources on land, there is often far less moisture to be
distributed inland.

2. Normal soil profile:
Vegetation: the layer of plant life on top
Humus: the uppermost layer of soil where organic
material decomposes and leaves nutrients and
minerals
Top soil: area that includes the humus and where
nutrients and minerals may sink to
Sub soil: several layers of old soil which have been
pressurised by new soil
Bedrock: a layer made of solid stone
Aridisol profile:
Vegetation: a layer of plant life which is far sparser than
a normal profile, with only certain plants being able to
adapt to the conditions
Humus: a much thinner layer than a normal profile as
there is no decomposing matter to add to it
Top soil: also far thinner than a normal profile, contains
less minerals and nutrients
Sub soil: a single layer primarily made of sand and salt
making it hydrophobic with possible salinization
Bedrock: same as a normal profile, made of solid stone
Hydrophobility: Fear/Hatred of water. Sand will no
absorb water, it will sit on top and cause the high salt
content to salinize when dry
Salinized soil: Where the high salt content has
formed a crust on top which solidifies, allowing even
less water through to the soil if any
Desert Flora: Aloe Vera Desert Flora: Desert Melon
•Uses it’s tissue to store large volumes of water •Thrives in warm climates
•Thick fleshy leaves for tissue •Single creeper can produce several fruit
•Leaf cuticle is thick and covered in wax to reduce •Only grow to shrub size to reduce surface area,
water loss stomata and transpiration
•Maintains the high volume of water for dry periods •Horns deter animals that may eat it

3. Desert Flora: Saguaro Cactus Desert Fauna: Gila Monster
•Grow as tall as 50 metres •Yellow, pink or orange colouration to camouflage
•Live for 200 years into surroundings
•Large water storage space •Venomous
•Shallow net of roots •Can store fat in its tail
•Grows arms to increase reproduction •Thick skin prevents water loss
•Needles reduce transpiration and deter animals •Spends 98% of its life underground
•Very green to allow maximum photosynthesis •Slow metabolic rate – fat lasts longer so it needs to
feed less often
Desert Fauna: Sidewinder Desert Fauna: Fennec fox
•Well developed muscles allow sideways movement •Nocturnal and burrow during the day
to cope with shifting sands •Extremely large ears to increase surface area to
•Scales over eyes to protect them volume ratio and keep cool
•Movement reduces the time its body touches the •Good hearing for hunting
hot sands •Camouflaged colouration
•Nocturnal to avoid heat of the day •Thick fur on feet to insulate from the heat
•Sandy colouration to camouflage into surroundings •Kidneys restrict water loss
Human pressures on deserts: Population growth Human pressures on deserts: Population growth
Sonoran Desert Positives
1970 2.3 million 4% annual growth Tourism produces economic stability
1995 5.5 million 3% annual growth Better facilities are developed e.g. Hospitals
2001 8 million+
Mexicali has 500,000 people Negatives
Loss of plants and animals
Reasons: Disruption of natural drainage system
Migration Depletion of water and food
Movement of retirees Increased flash floods due to new impermeable
Birth rate>Death rate surfaces e.g. Buildings and roads
Human pressures on deserts: Population growth Human pressures on deserts: Population growth
Mojave Desert Positives
Millions in tourist revenue
1.9 mil people in Las Vegas, 2.3 mil in the desert
Urban centres are sparse and spread out, reducing pressure
Divided amongst urban centres (Vegas, California)
on single areas
In 2003, 1.5 mil were present, 660,000 residents More people means more facilities
2000-2003 the population grew by 3%
Negatives
Reasons: Soil erosion and land degredation from residential and
Tourism industry tourist activites e.g. Use of all terrain vehicles
Urban sprawl and rapid growth e.g. South California
Military stations
It can effect the wildlife dramatically

4. Human Pressures on deserts: Mining Human Pressures on deserts: Mining
Roxby Downs - Australia Positives
Largest source of uranium in the world Employs 1,136 of the 4,000 population, and 900
5th largest mine in the world commuters
Sold for $9.2 billion
Established in 1987
$5 billion expansion plan will lead to more jobs
It also produces copper, gold and silver
Negatives
Lots of water required to process the ores (35 milion litres
daily)
60 million tonnes rsdioactive waste
Dec 2003 145,000 tonnes of uranium solution spilled
Human pressures on deserts: Mining Human pressures on deserts: Mining
Tanami Desert – Australia Positives
Gold mining site since 1900 Boosts the economy
In 2010, a single operation produced 2 million oz of It allows countries to develop
Some profit was used for the development of aboriginal
gold
people
$30 milion has been invested in a deep shaft project
Since 1997, expenditure has been in excess of $12 Negatives
million Work is dangerous: In 2006, 17 were trapped, 14
escapred, 1 died, 2 found after 5 days
Destroys habitat and isn’t an unlimited resource
Machinery can be expensive
Human pressures on deserts: Farming Human pressures on deserts: Farming
Atacama desert – Chile Positives
Crops: Cucumbers, beans, cotton, olives, grapes Contributes to 20% of revenue
Livestock: Cattle, pigs, alpacas Makes use of unused land
Method: Solar panels create energy which is used to
pump water from the groundwater storage to irrigate Negatives
crops at night when evapotranspiration is at its Groundwater storage will not be replaced quickly –
lowest point the Atacama received 0.01in of rain a year
Farmers must compete with other industries e.g.
mining
Human pressures on deserts: Farming Human pressures on deserts: Farming
Sonoran desert – USA/Mexico Positives
Crops: 1.5 million tonnes of wheat, 100,000 Produces more food
potatoes, 177,000 oranges Contributes to revenue
Livestock: 1.4 million cattle, 1.2 million pigs, 38,000
sheep Negatives
Method: Dams and reservoirs are used to irrigate Less water for consumption
land when it is at its coolest in the night Water table dropping
Increased soil salinity

5. Sonoran Desert Conservation Plan Sonoran Desert Conservation Plan
The program was established in 1998 and targets 5 Achievements to date:
key areas: •Over 200 reports compiled
•Critical habitat and biological corridors •Over 60,000 acres in county management
•Riparian protection •Rehabilitation projects over another 200 acres
•Mountain parks and nature preserves •16% of perennial streamsides are either in or will so
•Cultural resources be in county management
•Ranch conservation •2,000 of the 16,000 acres of intermittent streamside
will be in the preservation network
Sonoran Desert Conservation Plan Sonoran Desert Conservation Plan
Positives
Has prevented some further damage from occuring Overall the plan has failed due to:
Restored some habitats
•More planning occuring than taking action
Tax is proportionate to cattle
•That nothing has been done in relation to the plan
Negatives since 2009, and that was a report on turtles with
More planning than action nothing 5 years prior
Nothing has been done since 2009
Land degredation cannot be reversed
Cost $174 million ($559.48 per km2)
Tried to save “endangered” owl but miscounted
Arid Recovery – Roxby Downs Arid Recovery – Roxby Downs
The program was set up to: Achievements to date:
•Facilitate the restoration of arid zone ecosystems •An exclusion fence has been built to protect native
•Protect a range of native biota e.g. Long-lived flora biota
which had been driven out by short-lived annual or •Radio tracking GPS collars were put on wild cats and
week species foxes to gain a greater understanding of them
•Re-introduce regionally extinct animals e.g. The •Native floras have been regenerated within the
greater stick nest rat, the western barred bandicoot reserve
and the woma python. •Research and monitoring has been developed to
help the program
Arid Recovery – Roxby Downs Arid Recovery – Roxby Downs
Positives
It protects threatened species from extinction and Overall the program is working as there are more
reintroduces those regionally extinct positive impacts than negative ones, primarily in
Raises awareness an gains volunteer involvement favour of the wildlife.
Natural area is conserved
Negatives
Though it had some problems initially, the fence does
Excluded animals could gain access when the fence was
washed out by rain
protect conserved animals from the excluded
Fence became rusted after 9 days predators and many are now becoming safer as a
Dingoes broke in and killed all foxes within 17 days species in the region.
It cost $12,432 AUD per km ($13,057.33 per km)

6. Dubai Desert Conservation Reserve Dubai Desert Conservation Reserve
The program was established to: Achievements to date:
•Create a permanently protected area which ensures •In 1997, camels were evicted from 5% of the country
the future for habitats to protect native species
•Protects natural resources and maintains original •In 1999, 70 Arabian Oryx were reintroduced to the
desert landscapes area in a 27km2 conservation reserve and 6000 native
•Ensures the community and visitors have access in a shrubs planted
sustainable way •Emrites Airline entered a 5 year sponsorship deal
•Registering to get international recognition for the worth $14 million. The government added $7 mil.
reserve under the United Nations Protected Area •The DDCR (4.7% of countries land) was created to
Management protect animals and landscape
Dubai Desert Conservation Reserve Dubai Desert Conservation Plan
Positives
The list of bird species in the DDCR rose from 60 to 126 Overall the plan has failed as, though it has made a
The 70 Oryx formed the basis of the herd of now 400
significant difference to biodiversity and saved
There has been a rapid recovery in plant biomass
endangered animals, it is far too expensive to be
Negatives
Ecological health and indigenous knowledge are in decline sustainable, even with tourism revenue being
Large areas of land are rapidly becoming urbanised generated
Overgrazing reduced the range of species and biodiversity
It is costly - $21 mil was required for initial infrastructure
across 225km2 (4.7%) = $93,333. per km2
There are 2 types of Tundra – arctic and alpine, caused The soil of tundra environments is also vastly
by either latitude or altitude. different from normal soil profiles. Where as
Arctic Tundra: is located 60◦ North in latitude and temperate environments have a ‘normal’ soil profile,
includes parts of Canada, Greenland, Russia and Alaska. and deserts have aridisol, tundra environments
There is a full 24 hours of light and a full 24 hours of generally have cryosol and inceptisol. There are often
darkness annually to class as arctic tundra. large areas of permafrost, ground which has been
frozen at or below 0◦c for two years or more.
Alpine Tundra: is found in mountain ranges around the
world. For each 10 metres altitude increased, the
temperate drops 1◦, so you would be able to have a
tundra environment 4000m above the equator (Andes)
Tundra Flora: Puya Raimondii
•Antifreeze chemical in sap
Frost heave results from water in the soil freezing and •Grow up to 10 metres high
forming ice, and as more water passes through •Takes between 80-150 years to flower
porous soils, it is able to grow bigger. Once a •Produces 8-12 million seeds
sufficient size, it may be able to lift soil above it,
causing ‘lenses’ of uneven ground levels.

7. Tundra Flora: Rhododendron Tundra Flora: Moss Campion
•Leaves photosynthesise even when cold •5-15cm tall
•Thrive in acidic soil •Close to the ground to conserve heat
•Grows at between 12,000 and 14,500 feet •Small leaves give it less exposure to the harsh
•Low lying to withstand strong winds environment
•Protective cushion shape to restrain moisture and
heat
•Plant is 10◦c warmer than its surroundings
Tundra Flora: Artic Willow Tundra Flora: Arctic Moss
•Forms pesticide to keep animals and insects away •Aquatic to avoid winds
•Suited to cold, dry places •1cm growth per year
•15-20cm tall to avoid high winds •Tiny rootlets 1 cell thick
•Oval shaped, pointed leaves •Stores fat
•15-50mm leave length •Long life span 7-9 years
•Dark green bottom, light green top
•Petals don’t fall off, they just release seeds
•Has adapted a shallow net of lateral shoots
Tundra Flora: Bearberry Tundra Fauna: Alpaca
•Low lying
•2-8 inches tall
•Thick bark and fine silk hairs for warmth
•Blooms between March and June (warmer months)
•Adapted to non-nutrient rich soils
•Doesn’t use moisture or heat
•Provides food for animals
Tundra Fauna: Wild Yak Tundra Fauna: Elk
•12 million in the world •Herbivores
•23 year life span •4 part stomach for bark, grass, shrubs and tree limbs
•Females have 20in horn, males have 40in horn •Heavy coat for warmth
•Use horns to dig up food •Strong legs to escape predators
•Long thick coat for warmth •Have antlers for 6 months of the year
•Hot digestive tract •Sharp hooves to lash out
•Travel in single sex herds •Teeth for grinding
•Only give birth when the temperature is above
freezing
•Move above snowline in summer

8. Tundra Fauna: Wolverine Tundra Fauna: Snowy Owl
•Related to weasel rather than bears •Thick layers of down and feathers
•Large teeth and jaws •Claws to pick up prey
•65-107cm tall •9.5 year life span in wild
•13 year life span •30 years + in captivity
•Hydrophobic thick coat •Wing span of 1.5 metres
•Large feet to spread weight •60-75cm tall
•5 large claws per foot for climbing •Camouflaged beak
•Pounces on prey from trees •Short sharp beak
•Lets other animals hunt then scavenges food •Eyes don’t move, head does
Tundra Fauna: Musk Ox Human pressures on tundra: Tourism in Iceland
•Herbivore Tourism created 7,385 jobs in 2000, 8,211 in 2006
•Breaks through ice to get to plants and 8,500 in 2009
•12-20 year life span Tourism related jobs make up a significant
•4-5 ft tall percentage of tourisms revenue
•Long fur coat for warmth Winter sports often attract tourists
•500-800lb
•Found in Alaska, Greenland and Russia
•Males and females have horns
Human pressures on tundra: Tourism in Iceland Human pressures on tundra: Pollution: Norilsk
Positives Located in a continuous permafrost zone in Russia,
Creates jobs, employment, increases foreign exchange and
covered in snow 250-270 days a year
regional development
Improves amenities and facilities, may encourage traditional Temperature ranges from -23◦c to 25◦c
customs and crafts Main reason is smelting of ores, approximately 4
Some sites may have higher call for preservation eg. Historical, million tonnes of cadmium, copper, lead, nickel,
cultural or environmental sites (volcanoes) arsenic etc. being released into the air every year
Negatives
6th most polluted city in the world
Inflation and higher land values, overdependence on tourism
industry (Eyjafjallajokull eruption) Population declined from 183,000 in 1982 to 131,900
Bad visitor behaiour, erosion of local cultures in 2005
Overuse of water, pressure on local resources, wildlife harmed
Human pressures on tundra: Pollution: Norilsk Human pressures on tundra: Mineral exploitation: Prudhoe Bay
Positives Largest oil field in North America
Company is worth £17 billion, 2006 net profit was £3 billion, Two major oil producers: BP and Phillips
employs cities workforce, investment in South African gold
5 other companies with financial interest
mining
Produces many jobs and deals with unemployment Produces 1 million barrels of oil a year
In 2015, SO2 emissions will be reduced by 2/3 15 million barrels in 25 year history, nearly 1/5 of the
Negatives total US consumption
Process to produce economic gain can still be costly
Respiratory disease from emissions amounts to 15.8% of child
deaths, life expectance 10 years below the rest of Russia
CNN claims there isn’t a tree with 48km, contamination has
been found 60km away, 1% of world’s pollution

9. Human pressures on tundra: Mineral exploitation: Prudhoe Bay Alaska Department of Fish and Game
Positives •Run water programs to make recommendations based
Oil and gas produce mass revenue, $5.18 billion in 2009, $95
on data and analysis
billion since 1957
•Establishes hydroelectric projects
Accounts for 41,744 jobs, 9.4% of Alaska’s total
New technology reduces damage caused by drilling •Works with the Alaska Clean Water Actions program
Negatives to bring resource agencies together
Success rate is low and expenditure is high, oil reserves will run •Work with private land owners in costa share
out eventually programs to restore habitats, e.g. Kenai peninsula
May force native Inuits out of their homes •Controlled areas e.g. Southern Southwest Islands
Freshwater resources drained, lowers planning permissions for
cannot use vehicles for black bear hunting
other forms of exploitation, significant damage to corals,
destruction to habitat from infrastructure e.g. Alaskan pipeline
•Sets laws and regulations in fish-bearing areas
Alaska Department of Fish and Game WWF
Positives •Support the Catlin Arctic survey to measure sea ice
Protected areas vary from wildlife refuges, critical loss
habitat areas, important waters and state parks •Assessing Arctic vunerability to climate change
220,051 acres provide protection for wildlife •Working with national governments and local
Negatives communities to promote networks of ecologically-
It’s limited just to certain parts of Alaska based Marine Protected areas
It will prevent oil drilling based revenue in •Welcomes the initiative in April 2009 that brought
conservation areas, also limiting jobs together ministers from the Arctic Council and Antarctic
Inuits who rely on hunting in certain areas may be Treaty to discuss the environmental role of each area
penalized for it
WWF Conservation of Arctic Flora and Fauna
Positives •Serve as a vehicle for co-operation on species and
IUU fishing in the Barents Sea has been reduced by 50%
habitat management
It has significantly raised awareness of the issues
It aids and guides governments who can take actions •Facilitate knowledgeable decision making on
biodiversity management and conservation
Negatives •Promote sustainability of Arctic resources
They work around the world so only a limited amount of time •Report to key stakeholders and governments in
can be allocated to Arctic conservation
order to facilitate an active response to changes in
They are just a pressure group, they don’t actually hold any
power over governments the environment, providing policy recommendation if
necessary
Conservation of Arctic Flora and Fauna
Positives
It may not be a government organization, but does aid in the
decisions made by 9 member nations
Hundreds of programs are already underway, which CAFF will
co-ordinate
Negatives
It does more monitoring and assessing than taking action
It doesn’t actually hold any power and member nations are free
to leave