Succeed in IELTS Academic Listening Test 4 (Online Test)

The Jatbula Trail, located within Nitmiluk National Park, is a four-to-five day trek in Australia's Northern Territory. It follows an ancient Aboriginal song line, and the boulders along the way are scattered with rock paintings. There are five campsites along the trail, first, Biddlecombe Cascade, then Crystal Falls, 17 Mile Falls, Edith River Crossing, and finally Sandy Camp Pool. Only ten people at a time are allowed in each campsite, so you must book in advance, although usually you will not see another person on the trail. Every campsite has a source of permanent water, but otherwise, facilities at each campsite vary. Your first stop, Biddlecombe Cascades, has toilets and an emergency call device. The next two stops, Crystal Falls and 17 Mile Falls are the most developed campsites; both offer toilets, an emergency call device, and a checkpoint where you must sign in to help rangers locate you in case of an emergency. Edith River Crossing also has a checkpoint and an emergency call device, but no organised toilets are provided. Sandy Camp Pool is the most primitive site of all; there is nothing there other than a beautiful sandy beach where you can pitch your tent.

The trail begins at Nitmiluk Centre, where you must register and pay a deposit of 50 dollars. After registering, you may begin your trek. You'll follow the trail overlooking 17 Mile Creek on your left for 8 kilometres until you reach the first campsite, Biddlecombe Cascades, where you'll stop for the night.

On the second day, the track leads north from camp. After you have walked for about 5 hours and 10.5 kilometres, you'll reach Crystal Falls campsite located at a sharp bend in the trail. There's a marked trail from the campsite to the Crystal Fall viewpoint. Crystal Falls is 30 metres high, and it's breathtaking, so be sure to have a look.

The next day you'll change direction and head west across a valley and then northwest again for about 9.5 kilometres. The track is quite even and flat for the first part of the day, which is a welcome break from the rocky ground of previous days. Before you reach the next campsite, you will pass 'The Amphitheatre' - a butterfly and frog filled canyon that's important to the aboriginal people who have left intricate rock paintings on the rock walls. A few kilometres further you'll come to 17 Mile Falls campsite beside a series of rock pools and small cascades above 17 Mile Falls Creek. There is a lookout over the falls that shouldn't be missed, and is particularly beautiful at sunset.

On day four you'll take your longest hike, 15 and a half kilometres, going to the west. You'll cross a boggy area as you approach the Edith River. If you're tired you may camp here, where you first cross Edith River, or instead follow the river south, crossing it several more times before you reach the campsite at Sandy Camp Pool, where you can spend the last night of your adventure camping on a sandy beach beside a tranquil waterhole.

Leaving Sandy Camp Pool, the track continues through woodland until you pass a checkpoint at Edith River South. From here the trail is lined with the river on the left-hand side and high rocks on the right. One last stop is a must at Sweetwater Pool. This is a large waterhole surrounded by rocky ledges that is perfect for a picnic before you return to civilisation. Day trippers can access this point from Edith Falls so it may be your first encounter with another person since leaving Nitmiluk. After a swim make your way to Edith Falls, where your adventure ends. Make sure you deregister at the Edith Kiosk, and then take a hot shower.

L: Hi there, I'm Laura. I'm the laboratory technician for these chemistry labs, and Professor Mills has asked me to explain the procedure that you'll all have to go through to get your final year projects approved. Most of the procedure involves safety concerns, which we take very seriously. We don't want any uncontrolled explosions, no fires, and definitely no incidents with toxic gases.

D: You mean like what happened in 2008 when the whole science block had to be evacuated?

L: Yes, exactly! So you've heard about that already, Denise?

D: Professor Mills told us about it on the first day of class. It was hilarious!

J: Yeah, but I reckon some people must have gotten into a lot of trouble.

L: To be honest it was mortifyingly embarrassing for the chemistry department, because, not only could no one identify what the toxic substance was, but also at the time of the incident, no one was actually authorized to be carrying out experiments with any toxic substances whatsoever. It turned out a student had got a bit bored and had decided to do some spontaneous experimentation by mixing up some random powders that were lying around. This is actually incredibly foolish, because there are some extremely dangerous substances in the laboratory stores, and everyone was utterly shocked that someone of college age would do something so childish and irresponsible. And, in effect, this incident was the reason we developed the safety procedure that each of you must now go through before we let you loose in the laboratory to do your final year project. The procedure will force you to really be aware of safety issues, so just in case, at the moment, any of you think it would be a laugh to mix up some colourful substances or light things on fire for no reason, by the time you've worked your way through the procedure, you'll at least pause for a second thought; at least, we would hope so!

J: So, uh, can I ask something?

L: Yes, Jamie?

J: So, we're basically being punished because some other student was irresponsible?

L: Actually, the approval process isn't as bad as that. We can't really call it a punishment! It seems really very long and cumbersome at first, because you'll have to get a lot of different tasks stamped for approval by a lot of different staff members, and I'm sure most of them will have various concerns and suggestions. But my aim today is to break down the process, and explain all the different steps to you, so that it doesn't seem quite so bad.

L: All right, let's get started. As I said before, a number of different staff members will be giving you suggestions, and they may not always agree, so just to keep things clear, you should remember that the laboratory supervisor has the final say about whether or not an experiment may be done here, in our laboratory. Your professor has the final say on whether you can do a particular experiment for your project, provided it's approved by the laboratory, and I've got the final say on how it may be done.

So, the first step is that you will fill out this safety assessment form. You will have to have a fairly clear idea of your experiment, because you'll need to list all the chemicals you'll be using, the quantities you'll be using for each one, and the nature of the reactions that you'll carry out. You'll also be required to provide a week-by-week schedule so that we can be sure that whatever substances you're working with won't prove to be incendiary if they get mixed up with whatever the person next to you on the bench is getting up to. Really, for most of you this assessment form will be quite straightforward because you're simply not going to be working with anything very dangerous. But for some of you, particularly if you are working with any volatile substances, it could be a bit more complicated. You might have to justify the use of certain substances, or only be allowed to use them on particular days.

Now then, after you've filled out your safety assessment form, and given a copy to your professor, you will submit it to the laboratory supervisor, and he'll review it. This could take a couple of weeks so do it early, don't leave it to the last minute; he's a busy man. The laboratory supervisor will eventually make a recommendation to your professor about whether the experiment can go ahead, requires modifications, or may not be done. Next, your professor will either approve the project, or not. If your professor does not approve the project due to safety concerns, then you, the student, will be notified and you'll begin the process over again by submitting a new safety assessment form that takes into account those troublesome safety issues. Is everyone with me so far?

J: Uh..... I have a question.

L: Yes, Jamie?

J: Er, so if we have to wait weeks for the laboratory supervisor to give his approval, and then we have to re-do the form, uh, we're going to be quite behind our classmates who got approval on their first go. That's a bit unfair, isn't it? I mean, some people are going to have an advantage of several weeks over other people.

L: Well, you needn't really worry about getting behind at this stage; after all, you'll have six months to work on your final project. And you'll only get a two-week block of laboratory time, anyway, so there's time to wait for the laboratory supervisor, provided you get started promptly and don't leave it all to the last two months! Also, don't forget that this is only one step; there are plenty of other steps for other students to get hung up on farther down the line. It will all balance out.

D: But, um, Laura, what if our projects aren't approved?

L: Then you'll come up with another one. Don't get too attached to your project in the beginning. Projects get turned down. Let's see, last year I think only 15 projects got approval on their first go.

J: Out of how many?

L: Out of .... about ...... 45, I think; there are less of you this year. But still, be prepared to come up with an alternative project. There are plenty of people to help you if you need ideas; your professor, his RAs, even your fellow students. And don't forget that in the first months of your project the library will be your second home, and the librarians will be your greatest friends.

D: Laura, what's an RA?

L: RA stands for research assistant, like Jess, over there, in the lab coat. Hi, Jess! Now, once your professor has approved your project, you will need to write up a set of experiment safety procedure guidelines. This will include all the practical steps you'll take to keep safe, and exactly what you'll do if you have a spill or some such thing.

D: How will we know all this? We've got no experience in the laboratory.

L: Well, after your professor approves your project, he'll assign an RA to help you write the experimental safety procedure guidelines. You won't be on your own. Finally, once that's written, you'll give it to the laboratory technician, that's me, for approval. If I approve it, then you can begin your experiment. If there are problems, we'll sit down together and talk about it, then you and your assigned RA will come up with a way of making your experiment completely safe to conduct, you'll re-do the guidelines, and give it to me again, until it's approved. But the RAs know what they're doing so I don't expect there will be too many problems. Ok? Any questions?

To begin our topic on sustainable development in South America, I would like to briefly acquaint you with the 6 biomes present in the country. Each of these biomes has its own geographic and environmental features, has unique resources that people may exploit, and indeed, each is facing different threats from human development.

Biomes, if you recall, are regions that are climatically and geographically defined and contain distinct communities of plants and animals. They are sometimes named for the plant communities that occur such as forest, savannah, and grassland; whether these plants are evergreen or deciduous; and climatic factors as well, for example, tropical, temperate, etc.

All right, let's take a look at this map of Brazil. The largest biome in Brazil is the Amazonian Rainforest Biome, which you can see located in the north of the country. It's one of two rainforest biomes in Brazil; the second being the Atlantic rainforest Biome, which is located in a relatively narrow strip running up the eastern Atlantic coast. In the very southernmost part of Brazil, bordered by the Atlantic rainforest, lies the very small and relatively unstudied Pampas biome, which is grassland. Finally, stretching like a belt across the middle of the country, between the two rainforest biomes, lie the Pantanal, the Cerrado, and the Caatinga. Starting at the left of the map, you can see the smallest of the three, which is the Pantanal Biome a unique seasonally flooded wetland area. In the centre of the country is the Cerrado, the second largest biome in Brazil. Cerrado is tropical savannah - a scattering of grassland and deciduous forest that experiences a short dry season. Finally, the last biome, called Caatinga, is located between the Cerrado and the Atlantic forest in the north east of the country. The Caatinga has a very long dry season, lasting 8 to 9 months, and is covered in deciduous scrub.

So, let's begin with the Amazonian Rainforest Biome. As I mentioned previously, it's rainforest, and it's incredibly diverse. It contains the largest single reserve of biological organisms in the world. No one really knows how many species occur in the Amazon forest, but scientists estimate that there could be as many as 5 million. Recently this biome has been under a great deal of pressure from agriculture, with large swathes being cleared and burned to create pasture for the 19 million cattle that the area supports. However, the soils are acidic with very low levels of certain important minerals, and are quickly degraded when heavily grazed, which necessitates more clearing and burning of forest. The rainforest is further disturbed by selective logging of valuable tree species.

The second largest biome in Brazil is the Cerrado, which is a tropical savannah environment made up of sparse trees and drought resistant grasses. The Cerrado also contains a huge biodiversity; it's estimated that one third of Brazil's plant and animal species are located in this region. But since 1995, the cultivated pasture area in the Cerrado has increased by almost 70%. It is a common practice to use newly cleared land for the cultivation of crops for a few years, and then when it starts to degrade, to use it for pasture for cattle. The Cerrado now supports 72.3 million cattle, which amounts to 41 percent of the cattle in Brazil.

Next, we have the biome called the Caatinga, which is a tropical dryland with a dry season that lasts 8 or 9 months of the year. Vegetation is deciduous, sparse and thorny, and contains a high number of species endemic to Brazil. Agriculture is limited by the lack of water but this biome supports 8.8 million goats and 8.1 million sheep, besides 23.9 million cattle.

The Pantanal Biome, a wetland formed by the flooding of the rivers of the Paraguay basin, is the world's biggest flooded plain. Vegetation is patchy and variable; it consists of tall grasses, bushes, and widely dispersed trees similar to those of the Cerrado, except that in the Pantanal they are partially submerged for a portion of the year. Three million cattle are raised in this biome, however the available grazing area is limited by flooding so large areas can sustain only low numbers of animals. UNESCO recognizes it as a "World Biosphere Reserve" and also as a "World Natural Heritage Site." Ecotourism is becoming important in this region, which diversifies the economic activity.

The Atlantic Rain Forest is the most endangered biome in Brazil and also its most affluent region. It's the most important agricultural and industrial area of the country. It supports 36 million cattle, and most of the country's dairy production takes place there. More than 70% of the Brazilian population, the largest Brazilian cities and the production of about 80% of Brazil's gross domestic product are all located in what used to be the Atlantic Forest. Today, as a result, less than 10 per cent of the Atlantic forest is left. The Biome is also beginning to be recognised as ecologically very important; in the state of Bahia, for example, international researchers have identified a world record of 458 tree species in a single hectare of Atlantic Forest. That is even more diverse than the Amazon rain forest. At the moment, less than 2% of the remaining Atlantic forest is under protected status, and the scientific community is scrambling to secure what little undisturbed forest still remains.

Finally, the Brazilian Pampas Biome has a temperate climate - it's the only biome in Brazil that is not tropical. Grasslands scattered with shrubs and trees are the dominant vegetation. The shallow soil, originating from sedimentary rocks, often has an extremely sandy texture that makes it fragile and highly prone to water and wind erosion. The Pampas supports 26 million cattle and 6 million sheep, in mostly natural unmodified pastures; however this biome is being threatened with rapid conversion to the agriculture of cash crops.

All right, so, next week we will go into more detail about the economic policies of the Brazilian government in relation to the development of each of these biomes.