2015年7月11日雅思阅读真题解析--外朗教育
  考试概述：
  本次考试三篇文章两旧一新，第一篇讲保护森林，第二篇讲gesture，第三篇内容主要是关于英国莱斯特的剧院。
  Passage 1
  题材：生物类
  新旧情况：旧题
  题型：填空6+流程3+判断4
  文章大意：
  类似文章及旧题仅供参考
  Saving a Forgotten forests-- The longleaf pine
  Found only in the Deep South of America, longleaf pine woodlands have dwindled to about 3percent of their former range, but new efforts are under way to restore them.
  A 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 tall grass 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.
  B In longleaf pine forests, trees grow widely scattered, creating an open, park like environment, more like a savanna than a forest. The trees are not so dense as to block the sun. This openness creates a forest floor that is among the most diverse in the world, where plants such as many-flowered grass pinks, trumpet pitcher plants, Venus flytraps, lavender ladies and pineland bog-buttons grow. As many as 50different species of wildflowers, shrubs, grasses and ferns have been cataloged in just a single square meter.
  C Once, nearly 92 million acres of longleaf forest flourished from Virginia to Texas, the o
nly place in the world where it is found. By the turn of the 21st 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.pines
  D 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.
  E 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 lo
ngleaf flatwoods. It tucks its nest on the ground beneath dumps 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.’
  F 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."
  G 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 sorawling 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.
  H 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. Althoug
h the public often opposes any type of fire—and the smoke that goes with it—these frequent, low-intensity bums reduce the risk of catastrophic conflagrations. "Forests are going to bum," says Amadou Diop, NWF’s southern forests restoration manager. "It’s just a question of when. With prescribed bums, we can pick the time and the place."
  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. cost solutions.

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