Climate case studies

Page 1

Sahara, Sahel region (hot desert)

Background info:

North Eastern, Northern, North Western Africa

Northern hemisphere

Countries: Algeria, Niger, Sudan, Egypt

Vegetation adaptations:

Succulence: capture and store water in leaves, stems or roots

Drought tolerant plants: strategies that help tolerate droughts (can live without water)

Drought avoiding plants: only 'live' when there is water available (when it's dry they're dormant)

Cactus:

large stems for water storage

thick waxy cuticle to reduce water loss through pores

wide spread root system - can collect water easily

spikes instead of leaves: reduce SA for transpiration and protects from predators

Wildlife adaptations:

Camels:

Long eyelashes, opening nostrils, ears covered in hair àsand/dust doesn’t get in

Eyebrows shield eyes from sun

Drink up to 46 litres per session

Store fat in hump for energy

Body temperature fluctuates so less sweating

Wide feet so doesn’t sink in sand

Thick lips to eat prickly plants without pain

Colour allows them to blend in

Snakes:

Slither through grass/rocks à soundless, no alarm

Can enter narrow holes to find rodents

Flexible jaw to eat large prey

Teeth directed backwards (prey escape)

Forked tongue for smelling

Colour/pattern for camouflage

Threats:

Desertification: overcultivation of land due to population growth (for food) --> nutrients used up

Deforestation: fuel wood needed

Drought:climate change, less rain than 50 years ago (Egypt 125 mm a year)

Overgrazing: cattle, sheep, goats eat vegetables --> wind erosion

Salinity: water for irrigation contains mineral salts --> water evaporates --> salts --> crops die

Conservation (sustainable farming):

Less animals: less overgrazing, protective vegetation

Aforestation: roots hold soil together

Earth dams: collect & store water in wet season --> irrigation in dry season

Solar panels for energy (Algeria in Sahara)

Impacts:

13% GDP, 32% labour in farming

lost jobs, loss of income

Food shortages, price increase (25 to 89 million people --> population pressure)

Loss of fertile land: $70 billion to transfer water from lake Nasser to irrigate land (30% more land)

Deforestation --> desertification --> loss of vegetation

Soil salinity

Soil erosion (wind)

Page 2

Amazon Rainforest (tropical rainforest)

Background info:

A rainforest in Brazil and Colombia

Biggest rainforest in the world

In South America

Vegetation adaptations:

Buttress roots – rainforests soils is thin so shallow roots are needed to soak up nutrients in soil. These massive roots give the 30m trees extra stability in shallow soil

Stilt roots – provide tall trees with support is shallow rainforest soil

Red leaves – give protection from sunlight for plant saplings as reflect red light to protect internal organs for photosynthesis while still developing

Lianas – roots in ground and use other trees to climb up into canopy for sunlight. Some start in canopy and go down for roots

Leaf angling – leaves arranged at different angles so plant avoids shading its own leaves as competition for sunlight is high

Drip tips – waxy surface with pointed tips to enable excess rainwater to run-off. Prevents growth of algae (which would block out sunlight and reduce photosynthesis)

Epiphytes – live on surface of other plants (mostly tree trunks and branches) to get most sunlight in canopy

Thin bark – don’t need thick bark as plenty of water available. Smooth bark also makes it harder for plants to grow on it.

Wildlife adaptations:

Toucan:

Bright colours to attract mates

Strong claws for grip on branches

Stron bill for cracking nuts

Loud call to scare enemies

Nest in tree holes to hide from predators

Sloth:

Strong claws to hang to branches

Lengthy limbs to hang on to branches

Algae on fur for camouflage

Threats:

Mining: Carajas mine - largest iron ore mine in the world. Rainforest removed to get iron, copper, tin, aluminium, gold, manganese

Road building: to reach mines, transport ore, logging, for farming, basic communication - up to 50 km of deforestation on either side of the road

Farming: tuitional Amerindians - land cleared, farmed a few years, people leave and move on after burning some trees to fertilise soil. Kind of sustainable as it's only small area.

Logging: many trees cut down for wood, e.g. Mahogany

Conservation

Yosuni National Park: one of the most biologically diverse area in the world, 10 000 km2, Amazonian tribes live there (some don't even want contact with outside world)

Selective logging: only fell trees that are mature --> protects forest canopy, ground below is also protected BUT each selectively logged tree may damages 30 other trees by the way

Conservation swamps: country lowers its debt by agreeing to conservation activities, e.g. USA and Peru preserved jaguar in Peruvian rainforest

Responsible management and use: Forest Stewardship Council only approves responsible wood products. Company can use their logo, customers decide who to choose: sustainable or not product

Impacts:

Foreign currency from mining

Road network helps country develop

Only subsistence farming

Jobs created in mines

Communication is improved

Traditional ways of life are preserved

Deforestation

Forest logged --> more forest opened up --> more logged

Sustainable farming