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Test Type | Matching features, Matching Heading, Multiple Choice, note/form/sentence completion, T/F/NG |
READING PASSAGE 1
You should spend about 20 minutes on Questions 1-13 which are based on Reading Passage 1 below.
The Forgotten Forest
Found only in the Deep South of America, longleaf pine woodlands have dwindled to about 3 percent of their former range, but new efforts are under way to restore them.
THE BEAUTY AND THE BIODIVERSITY of the longleaf pine forest are well-kept secrets, even in its native South. Yet it is among the richest ecosystems in North America, rivaling tallgrass prairies and the ancient forests of the Pacific Northwest in the number of species it shelters. And like those two other disappearing wildlife habitats, longleaf is also critically endangered.
In longleaf pine forests, trees grow widely scattered, creating an open, parklike environment, more like a savanna than a forest. The trees are not so dense as to block the sun. This openness creates a forest 1oor that is among the most diverse in the world, where plants such as many-1owered grass pinks, trumpet pitcher plants, Venus 1ytraps, lavender ladies and pineland bog-buttons grow. As many as 50 different species of wild1owers, shrubs, grasses and ferns have been cataloged in just a single square meter.
Once, nearly 92 million acres of longleaf forest 1ourished from Virginia to Texas, the only place in the world where it is found. By the turn of the 2lst century, however, virtually all of it had been logged, paved or farmed into oblivion. Only about 3 percent of the original range still supports longleaf forest, and only about 10,000 acres of that is uncut old-growth—the rest is forest that has regrown after cutting. An estimated 100,000 of those acres are still vanishing every year. However, a quiet movement to reverse this trend is rippling across the region. Governments, private organisations (including NWF) and individual conservationists are looking for ways to protect and preserve the remaining longleaf and to plant new forests for future generations.
Figuring out how to bring back the piney woods also will allow biologists to help the plants and animals that depend on this habitat. Nearly two-thirds of the declining, threatened or endangered species in the southeastern United States are associated with longleaf. The outright destruction of longleaf is only part of their story, says Mark Danaher, the biologist for South Carolina’s Francis Marion National Forest. He says the demise of these animals and plants also is tied to a lack of fire, which once swept through the southern forests on a regular basis. “Fire is absolutely critical for this ecosystem and for the species that depend on it,” says Danaher.
Name just about any species that occurs in longleaf and you can find a connection to fire. Bachman’s sparrow is a secretive bird with a beautiful song that echoes across the longleaf flatwoods. It tucks its nest on the ground beneath clumps of wiregrass and little bluestem in the open under-story. But once fire has been absent for several years, and a tangle of shrubs starts to grow, the sparrows disappear. Gopher tortoises, the only native land tortoises east of the Mississippi, are also abundant in longleaf. A keystone species for these forests, its burrows provide homes and safety to more than 300 species of vertebrates and invertebrates ranging from eastern diamond-back rattlesnakes to gopher frogs. If fire is suppressed, however, the tortoises are choked out. “If we lose fire,” says Bob Mitchell, an ecologist at the Jones Center, “we lose wildlife.”
Without fire, we also lose longleaf. Fire knocks back the oaks and other hardwoods that can grow up to overwhelm longleaf forests. “They are fire forests,” Mitchell says. “They evolved in the lightning capital of the eastern United States.” And it wasn’t only lightning strikes that set the forest aflame. “Native Americans also lit fires to keep the forest open,” Mitchell says. “So did the early pioneers. They helped create the longleaf pine forests that we know today.”
Fire also changes how nutrients flow throughout longleaf ecosystems, in ways we are just beginning to understand. For example, researchers have discovered that frequent fires provide extra calcium, which is critical for egg production, to endangered red-cockaded woodpeckers. Frances James, a retired avian ecologist from Florida State University, has studied these small black-and-white birds for more than two decades in Florida’s sprawling Apalachicola National Forest. When she realised female woodpeckers laid larger clutches in the first breeding season after their territories were burned, she and her colleagues went searching for answers. “We learned calcium is stashed away in woody shrubs when the forest is not burned,” James says. “But when there is a fire, a pulse of calcium moves down into the soil and up into the longleaf.” Eventually, this calcium makes its way up the food chain to a tree-dwelling species of ant, which is the red-cockaded’s favorite food. The result: more calcium for the birds, which leads to more eggs, more young and more woodpeckers.
Today, fire is used as a vital management tool for preserving both longleaf and its wildlife. Most of these fires are prescribed burns, deliberately set with a drip torch. Although the public often opposes any type of fire—and the smoke that goes with it—these frequent, low-intensity burns reduce the risk of catastrophic con1agrations. “Forests are going to burn,” says Amadou Diop, NWF’s southern forests restoration manager. “It’s just a question of when. With prescribed burns, we can pick the time and the place.”
Diop is spearheading a new NWF effort to restore longleaf. “It’s a species we need to go back to,” he says. Educating landowners about the advantages of growing longleaf is part of the program, he adds, which will soon be under way in nine southern states. “Right now, most longleaf is on public land,” says Jerry McCollum, president of the Georgia Wildlife Federation. “Private land is where we need to work,” he adds, pointing out that more than 90 percent of the acreage within the historic range of longleaf falls under this category.
Interest among private landowners is growing throughout the South, but restoring longleaf is not an easy task. The herbaceous layer—the understory of wiregrasses and other plants – also needs to be re-created. In areas where the land has not been chewed up by farming, but converted to loblolly or slash pine plantations, the seed bank of the longleaf forest usually remains viable beneath the soil. In time, this original vegetation can be coaxed back. Where agriculture has destroyed the seeds, however, wiregrass must be replanted. Right now, the expense is prohibitive, but researchers are searching for low-cost solutions.
Bringing back longleaf is not for the short-sighted, however. Few of us will be alive when the pines being planted today become mature forests in 70 to 80 years. But that is not stopping longleaf enthusiasts. “Today, it’s getting hard to find longleaf seedlings to buy,” one of the private landowners says. “Everyone wants them. Longleaf is in a resurgence.”
READING PASSAGE 2
You should spend about 20 minutes on Questions 14-26 which are based on Reading Passage 2 below.
Storytelling, From Prehistoric Craves To Modern Cinemas
A
It was told, we suppose, to people crouched around a fire: a tale of adventure, most likely—relating some close encounter with death: a remarkable hunt, an escape from mortal danger; a vision, or something else out of the ordinary. Whatever its thread, the weaving of this story was done with a prime purpose. The listeners must be kept listening. They must not fall asleep. So, as the story went on, its audience should be sustained by one question above all: What happens next?
B
The first fireside stories in human history can never be known. They were kept in the heads of those who told them. This method of storage is not necessarily inefficient. From documented oral traditions in Australia, the Balkans and other parts of the world we know that specialised storytellers and poets can recite from memory literally thousands of lines, in verse or prose, verbatim – word for word. But while memory is rightly considered an art in itself, it is clear that a primary purpose of making symbols is to have a system of reminders or mnemonic cues – signs that assist us to recall certain information in the mind’s eye.
C
In some Polynesian communities, a notched memory stick may help to guide a storyteller through successive stages of recitation. But in other parts of the world, the activity of storytelling historically resulted in the development or even the invention of writing systems. One theory about the arrival of literacy in ancient Greece, for example, argues that the epic tales about the Trojan War and the wanderings of Odysseus traditionally attributed to Homer were just so enchanting to hear that they had to be preserved. So the Greeks, c. 750-700BC. borrowed an alphabet from their neighbors in the eastern Mediterranean, the Phoenicians.
D
The custom of recording stories on parchment and other materials can be traced in many manifestations around the world, from the priestly papyrus archive of ancient Egypt to the birch-bark scrolls on which the North American Ojibway Indians set down their creation myth. It is a well-tried and universal practice: so much so that to this day storytime is probably most often associated with words on paper. The formal practice of narrating a story aloud would seem – so we assume – to have given way to newspapers, novels and comic strips. This, however, is not the case. Statistically it is doubtful that the majority of humans currently rely upon the written word to get access to stories. So what is the alternative source?
E
Each year, over 7 billion people will go to watch the latest offering from Hollywood. Bollywood and beyond. The supreme storyteller of today is cinema. The movies, as distinct from still photography, seem to be an essentially modern phenomenon. This is an illusion, for there are, as we shall see, certain ways in which the medium of film is indebted to very old precedents of arranging ‘sequences’ of images. But any account of visual storytelling must begin with the recognition that all storytelling beats with a deeply atavistic pulse: that is, a ‘good story’ relies upon formal patterns of plot and characterisation that have been embedded in the practice of storytelling over many generations.
F
Thousands of scripts arrive every week at the offices of the major film studios. But aspiring screenwriters really need look no further for essential advice than the fourth-century BC Greek Philosopher Aristotle. He left some incomplete lecture notes on the art of telling stories in various literary and dramatic modes, a slim volume known as The Poetics. Though he can never have envisaged the popcorn-fuelled actuality of a multiplex cinema, Aristotle is almost prescient about the key elements required to get the crowds flocking to such a cultural hub. He analyzed the process with cool rationalism. When a story enchants us, we lose the sense of where we are; we are drawn into the story so thoroughly that we forget it is a story being told. This is. in Aristotle’s phrase, ‘the suspension of disbelief.
G
We know the feeling. If ever we have stayed in our seats, stunned with grief, as the credits roll by, or for days after seeing that vivid evocation of horror have been nervous about taking a shower at home, then we have suspended disbelief. We have been caught, or captivated, in the storyteller’s wet). Did it all really happen? We really thought so for a while. Aristotle must have witnessed often enough this suspension of disbelief. He taught at Athens, the city where theater developed as a primary form of civic ritual and recreation. Two theatrical types of storytelling, tragedy and comedy, caused Athenian audiences to lose themselves in sadness and laughter respectively. Tragedy, for Aristotle, was particularly potent in its capacity to enlist and then purge the emotions of those watching the story unfold on the stage, so he tried to identify those factors in the storyteller’s art that brought about such engagement. He had, as an obvious sample for analysis, not only the fifth-century BC masterpieces of Classical Greek tragedy written by Aeschylus. Sophocles and Euripides. Beyond them stood Homer. Whose stories oven then had canonical status: The Iliad and The Odyssey were already considered literary landmarks-stories by which all other stories should be measured. So what was the secret of Homer’s narrative art?
H
It was not hard to find. Homer created credible heroes. His heroes belonged to the past, they were mighty and magnificent, yet they were not, in the end, fantasy figures. He made his heroes sulk, bicker, cheat and cry. They were, in short, characters – protagonists of a story that an audience would care about, would want to follow, would want to know what happens next. As Aristotle saw, the hero who shows a human side some flaw or weak-ness to which mortals are prone is intrinsically dramatic.
READING PASSAGE 3
You should spend about 20 minutes on Questions 27-40 which are based on Reading Passage 3 below.
Living Dunes
When you think of a sand dune, you probably picture a barren pile of lifeless sand. But sand dunes are actually dynamic natural structures. They grow, shift and travel. They crawl with living things. Some sand dunes even sing.
A
Although no more than a pile of wind-blown sand, dunes can roll over trees and buildings, march relentlessly across highways, devour vehicles on its path, and threaten crops and factories in Africa, the Middle East, and China. In some places, killer dunes even roll in and swallow up towns. Entire villages have disappeared under the sand. In a few instances the government built new villages for those displaced only to find that new villages themselves were buried several years later. Preventing sand dunes from overwhelming cities and agricultural areas has become a priority for the United Nations Environment Program.
B
Some of the most significant experimental measurements on sand movement were performed by Ralph Bagnold, a British engineer who worked in Egypt prior to World War II. Bagnold investigated the physics of particles moving through the atmosphere and deposited by wind. He recognised two basic dune types, the crescentic dune, which he called “barchan,” and the linear dune, which he called longitudinal or “sief ’ (Arabic for “sword”). The crescentic barchan dune is the most common type of sand dune. As its name suggests, this dune is shaped like a crescent moon with points at each end, and it is usually wider than it is long. Some types of barchan dunes move faster over desert surfaces than any other type of dune. The linear dune is straighter than the crescentic dune with ridges as its prominent feature. Unlike crescentic dunes, linear dunes are longer than they are wide—in fact, some are more than 100 miles (about 160 kilometers) long. Dunes can also be comprised of smaller dunes of different types, called complex dunes.
C
Despite the complicated dynamics of dune formation, Bagnold noted that a sand dune generally needs the following three things to form: a large amount of loose sand in an area with little vegetation—usually on the coast or in a dried-up river, lake or sea bed; a wind or breeze to move the grains of sand; and an obstacle, which could be as small as a rock or as big as a tree, that causes the sand to lose momentum and settle. Where these three variables merge, a sand dune forms.
D
As the wind picks up the sand, the sand travels, but generally only about an inch or two above the ground, until an obstacle causes it to stop. The heaviest grains settle against the obstacle, and a small ridge or bump forms. The lighter grains deposit themselves on the other side of the obstacle. Wind continues to move sand up to the top of the pile until the pile is so steep that it collapses under its own weight. The collapsing sand comes to rest when it reaches just the right steepness to keep the dune stable. The repeating cycle of sand inching up the windward side to the dune crest, then slipping down the dune’s slip face allows the dune to inch forward, migrating in the direction the wind blows.
E
Depending on the speed and direction of the wind and the weight of the local sand, dunes will develop into different shapes and sizes. Stronger winds tend to make taller dunes; gentler winds tend to spread them out. If the direction of the wind generally is the same over the years, dunes gradually shift in that direction. But a dune is “a curiously dynamic creature”, wrote Farouk El-Baz in National Geographic. Once formed, a dune can grow, change shape, move with the wind and even breed new dunes. Some of these offspring may be carried on the back of the mother dune. Others are born and race downwind, outpacing their parents.
F
Sand dunes even can be heard ‘singing’ in more than 30 locations worldwide, and in each place the sounds have their own characteristic frequency, or note. When the thirteenth century explorer Marco Polo encountered the weird and wonderful noises made by desert sand dunes, he attributed them to evil spirits. The sound is unearthly. The volume is also unnerving. Adding to the tone’s otherworldliness is the inability of the human ear to localise the source of the noise. Stéphane Douady of the French national research agency CNRS and his colleagues have been delving deeper into dunes in Morocco, Chile, China and Oman, and believe they can now explain the exact mechanism behind this acoustic phenomenon.
G
The group hauled sand back to the laboratory and set it up in channels with automated pushing plates. The sands still sang, proving that the dune itself was not needed to act as a resonating body for the sound, as some researchers had theorised. To make the booming sound, the grains have to be of a small range of sizes, all alike in shape: well-rounded. Douady’s key discovery was that this synchronised frequency — which determines the tone of sound — is the result of the grain size. The larger the grain, the lower the key. He has successfully predicted the notes emitted by dunes in Morocco, Chile and the US simply by measuring the size of the grains they contain. Douady also discovered that the singing grains had some kind of varnish or a smooth coating of various minerals: silicon, iron and manganese, which probably formed on the sand when the dunes once lay beneath an ancient ocean. But in the muted grains this coat had been worn away, which explains why only some dunes can sing. He admits he is unsure exactly what role the coating plays in producing the noise. The mysterious dunes, it seems, aren’t quite ready yet to give up all of their secrets.
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