Grade 11 Resources And Sustainability (T4) Flashcards
What is a resource?
A commodity or feature of the environment that people use to meet their needs.
What has led to a depletion of our natural resources (in the last 250 years)?
(3)
An increase in population
Each person uses more manufactured goods
Modern transport uses a lot of fuel
What are 4 types of resources?
Natural resources
Human resources (more skilled person is a more valuable)
Manufactured resources (e.g. roads, cars, buildings)
Financial resources
What is the relationship between resources and economic development?
Cities and towns developed where resources were available. Once established, they continued to grow (even once local resources ran out)
What is causing demand to increase rapidly?
2
Population increase and urbanisation
What is a renewable resource?
A resource that is continually replaced.
Why are non-renewable resources not continually replaced?
2
Either because they form very slowly or because they form under conditions that are unlike those present on earth today.
What are the 4 different ways that people relate to their natural resources?
Exploitation
Depletion
Conservation
Preservation
Exploitation
To make use of something. This can eventually cause a species to be depleted.
Depletion
Reduce the number of a species by over-exploiting or degrading the environment
🍃🍂🍂🐿
Conservation
To protect a species or habitat for future use (e.g. by replanting trees)
Preservation
To keep in its present condition. Areas of the earth that are still untouched by humans. 🐚
What is sustainability?
A process of change whereby exploitation of resources meets the current need of humans without endangering future needs.
What are the two main factors contributing to non-sustainability?
Increase in population (worse in LEDC’s)
Increase in stress on natural resources caused by climate change
What can developed countries do to promote sustainability?
Bring their wants closer in line with their needs
How can disadvantaged people with few natural resources meet their needs sustainably?
(3)
- Develop technology that can be used and afforded by the locals and which can be recycled (e.g. inexpensive solar-operated cooking devices)
- Using natural resources without damaging the environment (e.g. growing wood that lasts longer when burnt, using solar power)
- Educating rural people to improve productivity on farms in an affordable way (e.g. to use improved seed, to use manure to make compost to improve fertility of fields)
Life straws and wind power are 2 more examples of improving sustainability and quality of life in rural areas
Probably won’t need to know😊
Give 4 examples of environmental damage causes by development
Ozone depletion Climate change Increased environmental despoliation Factories built on natural habitat Air pollution
Give 3 examples of how development can positively impact the environment
Environmental resources are efficiently used for development in a sustainable way
Raw materials from the environment are processed to uplift the local community and improve quality of life
Infrastructure improved for all (e.g. the building of dams)
Give 4 possible solutions to negative environmental impact
Companies forced to take responsibility for their actions (e.g. building of dams)
Environmental Impact Assessments (EIA’s) made compulsory
Smoke stack filters and taller smoke stacks builts
Smoke scrubbers (filter)
Afforestation
Reforestation
What do you call conservation areas that are linked to allow game to roam freely?
Wild life corridors
What is soil erosion?
The loss of soil from the ground’s surface by wind or water.
When does soil erosion usually start?
When there’s not enough vegetation to protect the soil from being washed or blown away.
What are the 3 agents that start soil degradation?
- Natural physical processes
- Animals
- Humans
What are the 4 human agents of erosion?
Deforestation
Ploughing downslope
Over-cropping
Overgrazing
Deforestation
Clearing of forests to provide timber for export, farmlands or buildings.
How can unprotected soil be eroded by heavy rain?
2
Rain splash loosens soil particles.
Run-off carries soil away.
Why would ploughing downslope result in more soil erosion?
This leads to furrows where rain can run off fast and carry soil away.
What is over-cropping?🙂
When farmers plant the same crop every year without replenishing the humus. The soil gets sandy and can then be blown away by wind.
What is over-grazing?🙂
Animals remove vegetation and cause compaction. Then the soil is easily eroded.
What can overgrazing cause?
Arid and semi-arid conditions
Name and explain 4 ways in which humans can have a positive impact on soil formation.
Mineral content: fertilizer can be added to increase its ability to produce crops.
Irrigating: water added to soil to support biota which helps humus to form. It also speeds up weathering of the bedrock and soil formation.
Drainage schemes: allows oxygen into the soil and decreases acidity
Windbreaks and strip cropping: reduces soil loss
Increase biota: land left fallow and new plants and animals introduced.
Time: soil left alone (new material can be added to soil to speed up soil rejuvenation)
What are biota?
Organisms living in soil.
What is rain splash?
Rain drops hitting soil and loosening soil particles
How much does deforestation increase run off?
From 3% to 70%
How can animals impact erosion?
3
Compact the soil.
Kill the roots of plants.
Create furrows which can become dongas or gullies.
How can physical agents of erosion lead to soil loss?
Causes like climate change decrease the vegetation cover. Soil degradation occurs, leading to soil loss.
List 4 strategies to prevent and control soil erosion.
Contour ploughing Strip cropping (growing different crops in parallel strips) Afforestation Not ploughing on steep slopes Crop rotation Avoid overgrazing Windbreaks Retain soil cover
What process causes plant and animal remains to become humus in soil?
Decomposition
How can climate affect soil? Refer to hot, humid climates and cold, dry climates.
(4+4)
Hot, humid climate:
Weathering takes place at a faster pace.
Humidity increases amount of vegetation and influences the type of vegetation.
High rainfall helps with leaching and eluviation of soil.
Better quality soil.
Dry climate:
Weathering is slower.
This decreases the amount of vegetation and therefore humus created.
Soil is therefore thin and poor.
What is a donga?
A furrow, gulley or sinkhole
What is fallowing?🙂
Leaving land ploughed but uncultivated and unseeded.
Soil
Loose material of the earth’s surface in which plants grow.
Name and briefly describe the 5 layers of soil in order from top to bottom.
O Horizon: organic layer, humus A Horizon: eluvial layer B Horizon: illuvial layer C Horizon: unconsolidated material R/D Horizon: bedrock
Describe the O Horizon.
Humus is decayed organic material that forms the top layer of soil and provides nutrients for the soil.
Describe the A Horizon.
True soil. The fertile topsoil made up of finer soil particles and nutrients. Important for farming.
Describe the B Horizon.
Subsoil. Coarser soil particles. Usually less fertile.
Describe the C Horizon.
Disintegrated parent rock which has been partially broken down through weathering.
Describe the R/D Horizon.
Regolith/ parent rock. Has not been broken up by weathering (solid).
Eluviation
Particles of soil and minerals are transported in solution downward through the horizons.
Illuviation
The deposition of particles and minerals in the B horizon
Leaching
Nutrients are washed from the A horizon downwards.
Calcification/ salination
Excessive evaporation causes lime or calcium to move upwards and be deposited on top of the surface, resulting in a hard layer that reduces infiltration.
What do you know about soil that is grey and where is it found?
Low humus content
Arid areas
What do you know about soil that is dark brown and where is it found?
High humus content
Grasslands
What do you know about soil that is red?
There is a high iron content
What do you know about soil that is whitish?
There is excessive calcification
What do you know about soil that is yellow?
There is excessive leaching
What do you know about soil that is bluish?
Marshy. Weak drainage.
In what pH of soil do garden plants typically grow best in?
Neutral or slightly acidic soil
What causes soil to be acidic?
Excessive leaching
Weathering
The weakening of rock through mechanical weathering, biological weathering and chemical weathering.
Mechanical weathering
Extremes in temperature cause rocks to weaken and break down.
Biological weathering
Breaking down of rocks by plants and animals
Chemical weathering
Chemicals in rocks change due to processes involving water and oxygen.
What does the texture of soil determine?
The drainage quality of the soil.
When is soil considered to be loamy?
When there are equal proportions of clay, silt and sand. (Better👍)
What is meant if the texture of soil is clay loam?
2
It has a higher clay content. Not porous, so water does not easily pass through.
What does the structure of soil influence?
The rate of water absorption and erosion.
What are soils that group easily referred to as?
Soil structure
peds
What are soils that do not group easily referred to as?
apeds
Which 2 factors play an important role in soil formation?
Climate and time
How does time impact soil formation?
Time is needed for decomposition and weathering to take place to create all the horizons.
Study the processes of a coal power station (yellow ‘booklet’). Don’t need to know for gr.11 but probably will for gr.12.
🌺
What is the national grid?
The storage and distribution centre for our electricity.
Write the names of the following items in the correct order in which they are uses to make electricity:
Boiler. Generator. Coal pulveriser. Transformer. Transmission lines. Turbine.
(Learn in matric)
Coal pulveriser. Boiler. Turbine. Generator. Transformer. Transmission lines.
Name 4 impacts of coal mining and thermal power stations on the environment.
Destruction of habitats, removal of vegetation and forests, and threatened plants and animals.
Solid waste dumps and fine dust.
Methane gas and harmful chemicals released.
Acid rain, air pollution and lung disease.
Environmental despoilation.
Environmental despoilation
Using non-renewable resources which produce solid and gaseous waste.
Name 4 non-renewable resources.
Oil (petroleum)
Natural gas
Uranium
Fuelwood
Name 4 renewable energy sources
Hydroelectric power Solar Wind Geothermal (natural heat of the earth's rocks, usually brought to the surface by hot water and steam) Waves and tides Biomass and biogas
Name 4 advantages of wind energy
Freely available Renewable No harmful emissions Saves coal and water. No excess heat produced. Farmers can farm underneath it.
Name 4 disadvantages of wind energy
Strong, continuous wind needed Initially expensive Can interfere with TV signals Noise (a low hum) Kills birds and bats Unsightly Large areas of land must be cleared to install turbines and they can destroy ecosystems
What are the different percentages of soil composition?
4
2% is humus
48% is weathered rock particles (mineral content of soil)
25% is water that has accumulated in the pore spaces
25% is gas in the pore spaces
What caused the Chernobyl disaster?
Inexperienced nightshift staff at a nuclear power station an early design that didn’t have important safety features
Name 4 advantages of using nuclear energy
Lower greenhouse gas emission
Low running costs (but expensive to build or close down)
Low transport costs
New generation nuclear powerstations are built to be cheaper, safer and more reliable.
Safer than coal mines (fewer have died in the last 30 years)
Name 4 disadvantages of using nuclear energy
Waste disposal (Used nuclear fuel rods remain radioactive for 10 000 years. Safe storage is expensive and there are no permanent safe storage sites.)
Building costs reduced when energy production and nuclear production are combined. This can be globally threatening.
Earthquakes (earth tremors cause modern nuclear power stations to switch of and shut down)
Powerful earthquakes and tsunamis can cause radioactive spillage (hundreds of injuries but few deaths)
Previous accidents
