Fragile Environments Flashcards
Define the term ‘fragile environment’.
An ecosystem or biome which can be easily damaged, as it is unable to adapt to variations (changes) that may arise as a result of human and physical activities.
Define the terms ‘ecological footprint’ and ‘sustainability’.
Sustainability - Concerned with meeting the needs of the present in such a way
without compromising the ability of future generations to meet their own needs.
Ecological Footprint - A measure of the impact of human activities in terms of/considering the amount of biologically productive land (area or environment) necessary to collect enough water, food, energy, raw materials, and support waste disposal in order to support a particular lifestyle.
What are some of the human and physical causes that can destroy fragile environments?
Human :
- Intensive farming (agriculture)
- Habitat loss due to hunting and the cutting down of trees.
- Deforestation
- Climate Change (CC)
- Mining
- Desertification
Physical (Natural) :
- Climate Change - Milankovitch cycles, solar variation, volcanic activity.
- Drought
- Volcanic Activity
- Earthquakes
- Tropical Storms
Why do you think there has been an
increase in impact on fragile
environments in recent history?
- Increased resource consumption
• Building material, food, water, etc. - Population increase
• More people means more
resources needed, services such as education, healthcare, etc which means more land needed to be cleared.
Define the term ‘desertification’
The process by which once productive land becomes unproductive into a desert like landscape as a result of human and natural causes. This usually takes place on the edges of existing deserts.
Define the term ‘drought’
Drought - This is a period of time where there is a shortage of water, this may mean that water bodies become evaporated such as in the Murray Darling Basin (MDB) in Australia
What are the characteristics of desertification?
• Absence of surface water
• Evaporation
• Increased soil erosion as bare soil is revealed causing it to be vulnerable to wind erosion (this could get into water bodies and taken away (increased sedimentation)).
• Increased presence of dry, loose, sand-like soil.
• Vegetation becomes completely lost or degraded.
What are the causes of desertification?
• Population Growth- As the population increases the demand for resources such as food, water, and settlement also increases.
• Climate Change - Drought; water scarcity, crop failure, erosion, etc. Migration - No more resources to live sustainably - must move.
• Deforestation - Trees provide structure for the soil, when cut down the soil becomes vulnerable to erosion causing crop failure, etc.
Soil stores large amounts of carbon, when the soil erodes it releases the carbon leading to climate change.
• Overgrazing - Land used un-sustainably for animal grazing causing;
Mineral loss, soil erosion, and infertile soil.
• Over-cultivation - Plantations - Large farms growing the same type of crop for products such as palm oil. Mineral loss & Soil erosion.
• Drought - A period of time where there is a lack of water. This causes: Crop failure, Water scarcity, Dehydration & Soil Erosion.
• Migration - The process of moving settlement for certain reasons.
As the people make new settlement over-population occurs draining the land.
What are the impacts of desertification?
Social :
- Food and water shortages/insecurity - Crop failure; malnutrition, starvation, dehydration and heat strokes.
- Migration - As recourses run out, people migrate to regions where there are a sustainable amount of necessities and resources for them, their family, and their livestock.
- Increased presence of biting bugs due to temperature causing diseases such as mosquitoes = malaria.
- Conflict & Disputes - Conflict may arise over disputes over land between farmers as resources become scarce. This may turn into war harming the environment and its wildlife.
Environmental :
- Soil Degradation & Erosion - As the soil dries out, loses it’s nutrients/minerals, and plant/tree cover begin to decline the soil becomes vulnerable to wind erosion, and can easily be carried away by surface water.
- Soil releases carbon - Eroded soil loses it’s ability to store carbon compared to fertile soil. This contributes to climate change as the carbon is released into the atmosphere.
Economic :
- Farm income falls - Due to water scarcity, crop failure, food shortages and drought farmers cannot sell their produce to make a profit so will have to migrate to a better area where the soil and land is suitable for agriculture, etc.
- Government Dependancy - Widespread poverty; increased reliance on overseas aid and government grants.
Define the term ‘deforestation’.
The deliberate act of cutting down of/removing trees for their source of timber and/or to clear land for settlement, production and road building.
Identify one good and one service provided by forests.
• Goods - Source of timber (wood), food, medicines, etc.
• Services - Water purification and regulation, nutrient recycling, habitats for plants and animals, air purification (photosynthesis), tourist attraction, etc.
What are the causes of deforestation?
• Commercial Timber Extraction - Trees cut down for their valuable wood for furniture and building.
• Agriculture - Over-cultivation grazing. Forests burnt for cattle ranching.
• Settlement - Agriculture - pasture land. Land for towns and factories.
• Road Building - Forests cleared for roads, transportation and settlement.
• HEP - Hydro-Electric-Power - Forest flooding, mining for stone for material for dam.
• Mining - Large areas of forests cut down. Causes air and water pollution.
What are the impacts of deforestation?
• Economic Development - Loggers benefiting from selling timber for furniture and construction illegally and commercially. The consumer buys the product which has been manufactured.
• Habitat Loss - Animals & insects habitats are destroyed as a result of the trees being cut down. Biodiversity is lost, the food chain is broken, extinction.
• Climate Change - As forests are burned, they release the carbon they are storing into the atmosphere very fast. Tree roots provide structure for the soil and their leaf litter and organic matter helps the soil. When cut down the soil erodes and loses it’s fertility.
• Destruction of local communities - Communities and tribes who rely on the forest for survival and basic necessities are killed by loggers or kicked off the land.
• Flooding - As eroded soil is carried away by water bodies such as rivers an increased chance of flooding above its banks.
• Vapour Regulation - Trees help maintain/control a steady amount of water in the atmosphere - transpiration. The vapour reflects the sun’s rays cooling the Earth and stop the soil from eroding due to a lack of moisture.
Define the term ‘climate change’.
The change in climate in various ecosystems or biomes or globally as a result of greenhouses gases such as Co2 being released into the atmosphere.
What are the human and physical causes of climate change?
Human :
- Greenhouse Emissions - Gases such as Co2 being released into the atmosphere by factories and other causes. These gases cause the enhanced greenhouse effect.
- Deforestation - Trees photosynthesise, reducing the amount of Co2 and converting it into oxygen. When cut down they release the carbon they are storing into the atmosphere contributing to climate change.
- Soil Erosion - Soil stores carbon, when they lose their structure due to the up-rooting of plants and trees they release that carbon.
Physical (natural) :
- Milankovitch Cycles - Slight tilts/movements in the Earth’s orbit heating the colder areas and cooling the hotter areas.
- Sunspots & Solar Flares - Extremely hot areas of the sun shining on the Earth’s surface warming its average temperature.
- Volcanic Eruptions - As a volcano erupts, it releases fumes containing reflective properties such as sulphur. These reflect the sun’s rays cooling the Earth.
