Natural Resources Module Flashcards
what are natural resources and what do they include
the earth’s natural resources are thing that can be use by people that are found in nature. natural resources include:
a) Air
b) Water
c) Forests
d) Soil
e) Animals
f) Marine life
what is essential for all life on earth
air
what gasses is air made up of
78% - nitrogen
21% - oxygen
1 % - Carbon dioxide, Argon, Water vapour & other gasses
what are the 5 sectors of the atmosphere (Look at P2) and describe them
(Starting from the closest to the earth) 1 - Troposphere 2 - Stratosphere 3 - Mesosphere 4 - Thermosphere 5 - Exosphere
i) 95% of earth’s air found in Troposphere which stretches to 20 km above the earth’s surface
ii) the remaining 5% stretches to a height of about 280 km to the Thermosphere. it is here in the centre of Thermosphere where the International Space Station orbits the earth.
what are the different causes of air pollution in SA and what can this air pollution cause
causes of air pollution:
i) industry
ii) the burning of fossil fuels in power stations, fire and vehicles
air pollution can cause:
i) Respiratory problems
ii) Headaches
iii) Sleepiness
iv) or Lung cancer
Look at P4, what are the stages in the water cycle (must be able to label) and explain the diagram
1 - evaporation 2 - transpiration 3 - condensation 4 - precipitation 5 - run-off 6 - surface water 7 - infiltration 8 - substance outflow
Explain how given drawing (P4) of the water cycle works.
due to the heat from the Sun, water on the Earth’s surface evaporates while water transpirates from plants. the evaporated water rises in the form of water vapour into the air cooling at about 1 degree C per 100m until it reaches dew point temperature where it condenses and forms clouds, once clouds are saturated, precipitation occurs and water falls to the Earth. water will run off the land in rivers which will flow to lower areas until they either reach lakes, dams or the sea. some water however infiltrates the soil to form subsurface aquifers where some of this subsurface water will reach the sea.
where is most of our water
- 97% Earth’s water found in the oceans and it’s salty in nature. as desalination of water is expensive, very little sea water is used at drinking water.
- more than 66% of remaining water found in glaciers and ice caps.
- there is more fresh water below the surface of the earth then water in dams and lakes. wells, windmills and pumps are used to extract this water from the ground.
why does SA have rainfall that increases from west to east
due to the cold Benguela Current in the west and the warm Mozambique Current in the east, the rainfall increase from west to east, with most abundant rainfall occur in the east.
a) Why is this so
more rapid evaporation takes place over the warm Mozambique Current therefore more clouds and more rain.
why is drought and ever-present risk in SA
66% of SA receives less than 500mm average annual rainfall.
what do future predictions indicate will happen by 2025 to our water (SA)
the country’s water requirements will outstrip supply unless urgent steps are taken to manage the resource more sustainably.
what is the growing water crisis exacerbated by
i) Many of SA’s wetlands have been lost
ii) Pollution of catchment areas
iii) Alien plant infestations are using excessive water.
what are the 10 largest dams in SA (in order of size) and what river are they part of and in what province are they in
1 - Gariep Dam - Orange River - Border: Free State and Eastern Cape
2 - Vanderkloof Dam - Orange River - Border: Free State and Northern Cape
3 - Sterkfontein Dam - Nuwejaar Spruit - Free State
4 - Vaal Dam - Vaal River - Border: Gauteng, Mpumalanga and Free State
5 - Pongolapoort Dam - Phongolo River - KwaZulu-Natal
6 - Bloemhof Dam - Vaal River - Border: North West and Free State
7 - Theewaterskloof Dam - Riviersonderend - Western Cape
8 - Heyshope Dam - Assegaai River - Mpumalanga
9 - Woodstock Dam - Tugela River - KwaZulu-Natal
10 - Loskop Dam - Olifants River - Mpumalanga
What do forests do / why are they so important
a) trees provide soil from erosion
b) forests home to birds, animals and insects
c) forests can be source of food
d) forests can cut down to produce timber for construction, furniture and paper. also can be used as firewood.
e) forests produce oxygen
learn different forests in SA on P7
how well do you know this
describe soil as a resource
1 - animals that we eat & foods that are grown are dependant on soil. without soil nothing would be able to grow. it takes hundreds of years for soil to be made.
