IELTS Listening · Cam 2
Test 3 Part 4
Good morning. This morning we are continuing our look at Australia And its natural problems.
Level: B1 · 62 sentences
Transcript
- Good morning. This morning we are continuing our look at Australia
- And its natural problems.
- Actually, dryness or aridity, as it is generally called by geographers,
- Is probably the most challenging of Australia's natural problems.
- And so it's very important in this course for you to have a good understanding of the subject.
- For Australia, water is a precious resource,
- And its wise management is of the greatest importance.
- As I've said, Australia is a dry continent,
- Second only to Antarctica in its lack of rainfall.
- Long hours of hot sunshine and searing winds...
- Give Australia an extremely high rate of evaporation,
- Far more than in most other countries.
- It's estimated that approximately 87% of Australia's rainfall is lost through evaporation,
- Compared with just over 60% in Europe and Africa,
- And 48% in North America.
- You generally think of Africa
- As being a very hot and dry place,
- But it's not.
- In comparison with Australia.
- In many parts of Australia, standing water,
- That is, dams, puddles and so forth,
- Dry up rapidly, and some rainfall barely penetrates the soil.
- The reason for this is that the moisture is absorbed by thirsty plants.
- Some parts of Australia are dry
- Because rainwater seeps quickly through sandy soils and into the rock below.
- In parts of Australia, this water, which seeps through the sandy soil,
- Collects underground to form underground lakes.
- Water from these subterranean lakes can be pumped to the surface and tapped,
- And so used for various purposes above the ground.
- In fact, extensive underground water resources are available over more than half of Australia's land area.
- But most of the water is too salty to be used for human consumption
- Or for the irrigation of crops.
- However, most inland farmers do rely on this water for watering their animals and,
- Where possible, to a lesser extent, for irrigation.
- Underground water can flow very large distances
- And can be kept in underground reservoirs for a very long time.
- Water from these underground reservoirs bubbled to the surface
- As springs in some parts of the country,
- And these rare sources of permanent water were vital to early explorers of inland Australia
- And to other pioneers last century who used the springs for survival.
- But in many places,
- Levels have fallen drastically through continuous use over the years.
- This has necessitated the pumping of the water to the surface.
- Remarkably, underground water sources in Australia supply about 18% of total water consumption.
- So you can see it's quite an important source of water in this dry land.
- So, most of the consumption of water in Australia comes from water
- Which is kept above ground.
- More than 300 dams regulate river flows around the country.
- The dams store water for a variety of functions.
- The rural irrigation of crops,
- Without which many productive areas of the country would not be able to be farmed.
- The regulation of flooding,
- A serious problem which will be dealt with later in the course.
- And last but not least, the harnessing of the force of gravity...
- For the generation of electricity.
- That is all we have time for this morning,
- But you'll be able to do further study on this important area in the library.
- I have a handout here with references on the subject,
- So if you're interested,
- Please come up to the desk and take a copy.
- Next week's lecture is a case study of an outback farm.
- And it'll be going into detail about some of the problems we've discussed here.