02-Unit 1 Part 2.mp3

【A】I- Interviewer B- Brian Cowles
I: Brian Cowles is the producer of a new series of documentaries called TheEarth at Risk which can be seen on Channel 4 later this month. Eachprogram deals with a different continent, doesn't it, Brian?
B: That's right. We went to America, both North and South and then wewent over to Africa and Southeast Asia.
I: And what did you find in each of these continents?
B: Starting with Africa, our film shows the impact of the population on theenvironment. Generally speaking, this has caused the Sahara Desert toexpand. It's a bit of a vicious circle we find. People cut down trees forfirewood and their domestic animals eat all the available plants - andso consequently they have to move south as the Sahara Desert expandsfurther south. I mean, soon the whole of Mali will become a desert. Andin East Africa: here the grasslands are supporting too many animals andthe result is, of course, there's no grass - nothing for the animals to eat.I: I see. And the next flm deals with North America?
B: That's right. In the USA, as you know, intensive agriculture requiresa plentiful supply of rain for these crops to grow, I mean if there isn'tenough rain the crops don't grow. And growing crops stabilize soil,without them the top soil just blows away. This is also true for any regionthat is intensely farmed . most of Europe, for example.
I: And what did you find in South America?
B: In South America (as in Central Africa and Southern Asia) tropical forestsare being cut down at an alarming rate. This is done so that people cansupport themselves by growing food or to create ranches where cattlecan be raised to be exported to Europe or America as tinned meat. Theproblem is that the soil is so poor that only a couple of harvests arepossible before this very thin soil becomes exhausted. And it can't be fedwith fertilizers like agricultural land in Europe.For example, in Brazil in 1982 an area of jungle the size of Britain andFrance combined was destroyed to make way for an iron ore mine. Hugenumbers of trees are being cut down for export as hardwood to Japan,Europe, USA to make things like luxury furniture. These forests can'tbe replaced - the forest soil is thin and unproductive and in just a fewyears, a jungle has become a waste land. Tropical forests contain rareplants (which we can use for medicines, for example) and animals - one animal or plant species becomes extinct every half hour. These foresttrees also have worldwide effects. You know, they convert carbon dioxideinto oxygen. The consequence of destroying forests is not only that theclimate of that region changes (because there is less rainfall) but thischange affects the whole world. I mean, over half the world's rain foresthas been cut down this century (20th century).