来源：
小编： 1662雅思阅读机经分析
南京环球教育教研中心-李冠群
考试日期： | 2013年7月18日（本次为周四加试，回顾内容较少） |
Reading Passage 1 | |
Title: | Desertification in the US |
Question Types: | Matching TRUE/FALSE/NOT GIVEN |
文章内容回顾 | 介绍美国某地沙漠化现象的形成和治理 建议参考： 剑桥真题5：The impact of wilderness tourism 了解环保话题的背景词汇。 词汇整理： conservation 保护，保存v.s. conversation species endangered species 原文拓展阅读： DESERT FORMATION Desertification is accomplished primarily through the loss of stabilizing natural vegetation and the subsequent accelerated erosion of the soil by wind and water. In some cases the loose soil is blown completely away, leaving a stony surface. In other cases, the finer particles may be removed, while the sand-sized particles are accumulated to form mobile hills or ridges of sand. Even in the areas that retain a soil cover, the reduction of vegetation typically results in the loss of the soil's ability to absorb substantial quantities of water. The impact of raindrops on the loose soil tends to transfer fine clay particles into the tiniest soil spaces, sealing them and producing a surface that allows very little water penetration. Water absorption is greatly reduced; consequently runoff is increased, resulting in accelerated erosion rates. The gradual drying of the soil caused by its diminished ability to absorb water results in the further loss of vegetation, so that a cycle of progressive surface deterioration is established. In some regions, the increase in desert areas is occurring largely as the result of a trend toward drier climatic conditions. Continued gradual global warming has produced an increase in aridity for some areas over the past few thousand years. The process may be accelerated in subsequent decades if global warming resulting from air pollution seriously increases. There is little doubt, however, that desertification in most areas results primarily from human activities rather than natural processes. The semiarid lands bordering the deserts exist in a delicate ecological balance and are limited in their potential to adjust to increased environmental pressures. Expanding populations are subjecting the land to increasing pressures to provide them with food and fuel. In wet periods, the land may be able to respond to these stresses. During the dry periods that are common phenomena along the desert margins, though, the pressure on the land is often far in excess of its diminished capacity, and desertification results. Four specific activities have been identified as major contributors to the desertification processes: overcultivation, overgrazing, firewood gathering, and over irrigation. The cultivation of crops has expanded into progressively drier regions as population densities have grown. These regions are especially likely to have periods of severe dryness, so that crop failures are common. Since the raising of most crops necessitates the prior removal of the natural vegetation, crop failures leave extensive tracts of land devoid of a plant cover and susceptible to wind and water erosion. The raising of livestock is a major economic activity in semiarid lands, where grasses are generally the dominant type of natural vegetation. The consequences of an excessive number of livestock grazing in an area are the reduction of the vegetation cover and the trampling and pulverization of the soil. This is usually followed by the drying of the soil and accelerated erosion. Firewood is the chief fuel used for cooking and heating in many countries. The increased pressures of expanding populations have led to the removal of woody plants so that many cities and towns are surrounded by large areas completely lacking in trees and shrubs. The increasing use of dried animal waste as a substitute fuel has also hurt the soil because this valuable soil conditioner and source of plant nutrients is no longer being returned to the land. The final major human cause of desertification is soil salinization resulting from over irrigation. Excess water from irrigation sinks down into the water table. If no drainage system exists, the water table rises, bringing dissolved salts to the surface. The water evaporates and the salts are left behind, creating a white crustal layer that prevents air and water from reaching the underlying soil. The extreme seriousness of desertification results from the vast areas of land and the tremendous numbers of people affected, as well as from the great difficulty of reversing or even slowing the process. Once the soil has been removed by erosion, only the passage of centuries or millennia will enable new soil to form. In areas where considerable soil still remains, though, a rigorously enforced program of land protection and cover-crop planting may make it possible to reverse the present deterioration of the surface. |
难度分析 | 本篇文章话题属于环保类，通俗易懂，在剑桥真题中有大量类似参考。是非常合理的卷面上第一篇的设定。 |
Reading Passage 2 | |
Title: | Hatching 鸟类孵蛋 |
Question types: | Identify information Matching TRUE/FALSE/NOT GIVEN |
文章内容回顾 | 该篇文章段落不多，主题明确。 前几段都在讲一种鸟Sxx，第一段说它们孵出来之前会敲蛋壳，有的敲的猛，敲很快，一开始100下每秒，周围的蛋都能听到，然后长大一点会慢一点，敲的缓，大概60下每秒。敲的快慢表示着不同的意思，比如敲60下的是鼓励旁边的蛋快点develop，通过敲击产生的交流，最后这些蛋会在同一时间孵化（大自然真神奇）。 第二段讲了这个同时孵化的原因，如果孵化是一批一批的，鸟妈妈移走一批孵出来的chicks的时候，别的就可能被predators盯上。 所以一起孵出来全家大转移是最安全的方法。 后面比较了几个鸟的喂食方式，s鸟只需要妈妈的提示，有的完全依靠妈妈，有的完全独立觅食。 然后一段又讲了好几种其他的鸟，大概是讲它们怎么运输刚出生的infants。 |
难度分析 | 动物类话题是传统经典话题之一，内容简单易懂趣味性强。 |
Reading Passage 3 | |
Title: | 暂无 |
文章内容回顾 | 本篇文章为新题， 现场回忆1：人类文明和社会衰落的过程。 现场回忆2：某种古代人种和其社会结构的介绍，之后它们衰退消失，在现代文明中又有所重现，提到了Iceland这个地方。 原文拓展阅读：（主要讲述了天气变化和冰岛地区的气候地貌简介） National Parks and Climate Change A National parks, nature reserves, protected areas and sites of special scientific interest (SSSIs) are an important part of the natural landscape in most countries. Their habitat and terrains vary massively, from tundra and glacier parks in the north to wetlands in Europe, steppes in central and eastern Europe, and prairie grasslands and deserts in other areas. Virtually all kinds of landscape are protected somewhere. And these protected areas are important for the variety of plant and animal life they harbour: caribou, bears, wolves, rare types of fish and birds. B But these areas are under threat from a recent peril - global climate change. No amount of legislation in any one country can protect against a worldwide problem. What exactly are the problems caused by climate change? David Woodward, head of the British Council for Nature Conservation, spoke to Science Now about some of these areas, and his first point highlighted the enormous variation in nature reserves. C "Each park or reserve is an ecosystem," he says, "and the larger reserves, such as those in Canada, may have several types of ecological subsystems within it. There are reserves which are half the size of Western Europe, so it doesn't make sense to talk about them as if they were all the same, or as if the microclimates within them were uniform." Woodward outlines some of the dangers posed by climatic change to parks in the northern Americas, for example. D "If climatic change is severe, and in particular if the change is happening as quickly as it is at the moment, then the boundaries of the park no longer make much sense. A park that was designated as a protected area 90 years ago may suffer such change in its climate that the nature of it changes too. It will no longer contain the animal and plant life that it did. So the area which once protected, say, a species of reindeer or a type of scenery, will have changed. In effect, you lose the thing you were trying to protect." This effect has already been seen in Canada, where parks which once contained glaciers have seen the glaciers melted by global warming. E Jennie Lindstrom, Chief Executive Officer of H2O, the charity which campaigns on an international level on behalf of mainland Europe's protected wetland and wilderness areas, is even more pessimistic. In a letter to Science Now, she has asserted that up to 70% of such areas are already experiencing such "significant change ... in climate" that the distribution patterns. of flora and fauna are changing, and that all areas will eventually be affected. She estimates that the most profound change is occurring in the northernmost parks in areas such as Finland, Greenland, Iceland and northern Russia, but adds that "there is no place which will not suffer the effects of global warming. What we are seeing is a massive change in the environment - and that means the extinction of whole species, as well as visual and structural changes which means that areas like the Camargue may literally look totally different in 50 or 60 years' time." F The problems are manifold. First, it is difficult or impossible to predict which areas are most in need of help - that is, which areas are in most danger. Predicting climate change is even more unreliable than predicting the weather. Secondly, there is a sense that governments in most areas are apathetic towards a problem which may not manifest itself until long after that government's term of office has come to an end. In poor areas, of course, nature conservation is low on the list of priorities compared to, say, employment or health. Third, and perhaps most important, even in areas where there is both the political will and the financial muscle to do something about the problem, it is hard to know just what to do. Maria Colehill of Forestlife, an American conservation body, thinks that in the case of climate change, the most we can realistically do is monitor the situation and allow for the changes that we cannot prevent, while lobbying governments internationally to make the changes to the pollution laws, for example, that will enable us to deal with the causes of the problem. "I am despondent," she admits. "I have no doubt that a lot of the work we are doing on behalf of the North American lynx, for example, will be wasted. The animal itself can live in virtually any environment where there are few humans, but of course its numbers are small. If climate change affects the other animal life in the areas where it now lives, if the food chain changes, then the lynx will be affected too. Less food for the lynx means fewer lynxes, or lynxes with nowhere to go." G Certainly, climate change is not going to go away overnight. It is estimated that fossil fuels burnt in the 1950s will still be affecting our climate in another 30 years, so the changes will continue for some time after that. If we want to protect the remnants of our wild landscapes for future generations, the impetus for change must come from the governments of the world.
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