Fragile Environments Case Studies Flashcards
Describe the location of the ‘Sahel’
The Sahel is a belt of land stretching from the West to East Coast of Africa
below the Sahara desert. It is under extreme desertification from climate
change.
What are the human and physical causes of desertification in the Sahel
Human:
• Population Increase - As the people multiply the demand for food, water and wood increases.
• Deforestation - Trees stop soil erosion and bind together soil. Their leaf litter and decaying organic matter acts as a compost. When burnt release the carbon they are storing contributing to climate change.
• Over-grazing and over-cultivation draining the soil which eventually erodes.
Physical:
• Climate change - The increased temperature causes a lack of moisture in the soil and drought and the soil inevitably erodes.
What are the impacts of desertification in the Sahel?
• As a result of desertification people and animals living in the Sahel face dehydration, malnutrition (scurvy), disease from the presence of mosquitoes and other bugs due to temperature increase, habitat loss (extinction), thus are forced to migrate and conflict may arise over the scarce amount of productive land left.
How is desertification being managed in the Sahel?
- To manage desertification projects such as the great green wall (introducing green plants and trees to transform the deserted desert land into fertile land once again) have been kicked off.
- Acacia trees are used due to their ability to tackle soil erosion and act as a barrier to wind and surface water runoff.
- Various water conservation strategies are being used such as demi-loons.
What and Where is the Murray-Darling-Basin?
• The Murray Darling Basin is mainly made of a combination of three complex
rivers (Murray, Darling and Murrumbidgee) which intermingle to make one
large Basin. The MDB is located in the south-eastern area of Australia. Altogether it is home to 2.7 million people.
What wildlife lives in the MDB and what biomes are there?
• It is home to 46 native fish and 120 waterbird
species. There are lots of different biomes such as swamps, bogs,
forestland, grassland and other wetlands/biomes.
What are the physical and human causes of desertification in the MDB?
Human causes include:
- Overgrazing - This drains the soil of it’s nutrients reducing it’s ability to store water for grass leaving animals with no more lush grass.
- Climate change - Causing drought from emissions by releasing stored carbon in the soil when it erodes.
- Un-sustainably using water (overusing it) - Drying up water sources reducing the amount of water - lowering of the water table.
Physical causes include:
• Soil erosion and degradation,
• Flooding
• Drought as a result of climate change and weather patterns.
What are the impacts of desertification in the MDB?
- Lack of food and water to feed animals and families.
- Farm income falls causing widespread poverty and an increased reliance on the government and/or overseas aid.
- Habitat Loss/Extinction
How is desertification being managed in the MDB?
Methods:
• Limiting water consumption allowing water for the environment,
• Maintaining water quality,
• Efficient irrigation systems - Not too much, not too little,
• Recycling water.
Who was and Why were people cutting down the trees in Costa Rica? Causes?
- Subsistence Farmers - To grow food and raise livestock needing space to have a home.
- Commercial Farmers - For wood to build barns, fences and other strategies to improve production in return for an income.
- Logging Companies - To make a profit by selling the timber to make furniture and construct.
- National Government of Costa Rica - To provide homes, schools, hospitals, road networks, etc. - For the growing population
What were the positive and negative impact of cutting down the trees in Costa Rica?
Pros:
• Homes and schools can be built for the growing population as well as roads, bridges, ports, and airports enabling more trade.
• New towns can be built and jobs created.
Cons:
• Biodiversity decreases as ecosystems and habitats are lost.
• Without the trees, the tropical soils are exposed to the heavy rain and win and thus the soil is eroded from the land and washed into the rivers leading to increased sedimentation.
What methods of sustainable management has Costa Rica employed to sustainably manage their rainforests?
- Ecotourism - This is an effective way for local people to find a way of earning an income from the trees without cutting them down.
- Replanting - In the last 20 years, over 100,000 trees of Costa Rica have been replanted mainly with fast growing eucalyptus and teak.
- Selective Logging - Using only the most valuable trees with specific dimensions and fallen trees where possible.
- Agroforestry - Farmers have turned to agroforestry, planting trees in their fields in between their crops. This has increased their incomes and improved the quality of soil.
- National Parks - ‘Up to 25% of the land has been set aside for conservation. They have created over 30 national parks as well as many wildlife reserves and corridors.
- Debt Reduction - In the Forever-Costa-Rica debt-for-nature swap deal, the USA wrote off debts of over $30 million owed by Costa Rica in return for a commitment to protect more of the rainforest.
Why is Tuvalu at risk of climate change?
Tuvalu has a population of 12,000, most of the islands of Tuvalu are low lying and the highest point on the islands is only 4.5 m above sea level. Its economy is reliant on fishing and other low income jobs with a GDP of only $4060
If sea levels continue to rise, the island will flood, this has caused many citizens to flee from the island fearing that their homes will become uninhabitable.
Describe the UK response to climate change.
The UK ranks 17th in World rankings of GHG gas emissions
– 1.1% of all emissions.
Large areas of the coast are at risk of flooding.
The UK government has pledged to cut emissions by 78%
by 2035.
To achieve this the UK would need to move to more
renewable sources of energy (there has been a huge
reduction in use of coal), a growth in the use of electric
cars (from 2035 all new cars will need to be electric), etc.
