大學(xué)英語自學(xué)教程 unit 24

[00:00.00]Unit 24 taxt A [00:04.60]Saving the Rainforests for Future Generations [00:07.77]為子孫后代救救熱帶雨林 [00:10.95]Rainforests are being cut and burned from Brazil to Indonesia [00:14.93]從巴西到印度尼西亞，熱帶雨林正在以極快的速度被砍伐和燒毀， [00:18.91]at such a rate that they could well disappear from the earth's surface before the year 2050. [00:23.44]它們很可能在2050年以前從地球表面消失。 [00:27.98]They are being cleared for valuable timber [00:30.71]砍伐的目的在于獲取珍貴木材 [00:33.44]and other resources [00:35.36]和其他資源 [00:37.28]to speed up the economic growth of the nations in which they are located. [00:40.96]以加快森林所在國家的經(jīng)濟發(fā)展速度。 [00:44.64]The most recent figures [00:46.77]最近的數(shù)字表明， [00:48.90]show that the area of rainforestdestroyed last year alone [00:52.02]僅去年一年熱帶雨林被毀的面積 [00:55.14]was bigger than the size of Great Britain and Ireland. [00:58.41]大于大不列顛及愛爾蘭的面積總和。 [01:01.68]If the present rate of deforestation is allowed to continue [01:05.16]如果目前這種砍伐森林的速度聽在發(fā)展下去， [01:08.65]the consequences for the earth will be great. [01:11.58]給地球帶來的后果會很嚴(yán)重。 [01:14.50]We shall see a massive upsetting of ecosystems, [01:18.03]我們將看到的是，大規(guī)模的生態(tài)失衡， [01:21.55]very large increases in soil erosion, [01:24.58]泥土流失大量增加， [01:27.61]increases in flooding and in drought, [01:30.55]水災(zāi)旱災(zāi)增多， [01:33.49]changes in rainfall patterns and regional [01:36.22]降雨模式的變化， [01:38.95]quite possibly global, changes in climate. [01:41.98]地區(qū)性氣候、很可能全球氣候的改變， [01:45.01]We shall also probably lose many rare plant and animal species. [01:48.89]我們還可能失去很多珍貴樹種和珍奇動物物種。 [01:52.77]According to many scientists, [01:55.10]據(jù)許多科學(xué)家說， [01:57.42]the burning of rainforests is also directly contributing [02:00.75]熱帶雨林被燒毀還直接起因于 [02:04.08]to the so-called greenhouse effect. [02:06.67]所謂的溫室效應(yīng)。 [02:09.25]This effect, they say, [02:11.23]他們說， [02:13.20]is raising average temperatures and sea levels as the polar ice caps recede. [02:17.38]隨著北極冰冠的消融，這一效應(yīng)正在使平均氣溫與海平面升高。 [02:21.56]The rainforest is essential in other areas also. [02:24.94]熱帶雨林對其他地區(qū)也必不可少。 [02:28.32]It is a medicine chest of unlimited potential. [02:31.41]它是一個具有無限潛力的醫(yī)藥寶庫。 [02:34.49]The US National Cancer Institute has identified 2,000 rainforest plants [02:38.96]美國國家抗癌協(xié)會找到的2000多種 [02:43.42]which could be beficial in fighting cancer. [02:46.31]雨林植物對戰(zhàn)勝癌癥可能有益。 [02:49.20]In today's pharmaceutical market [02:51.42]在今天的藥品市場上， [02:53.64]15 of the 125 drugs derived from plants were discovered in the rainforest. [02:58.66]125種從植物中提煉的藥品中有15種是在雨林中發(fā)現(xiàn)的。 [03:03.69]Plant species are not the only forms of lifethreatened with extinction in the rainforest. [03:07.87]植物種類并不是熱帶雨林中唯一受滅絕威脅的生物。 [03:12.05]Rare birds and animals that cannot be found anywhere else in the world [03:15.98]在世界上其它地區(qū)無法找到的稀有鳥類和動物 [03:19.92]have been disappearing at the rate of one a year [03:23.09]以每年一種的速度在消失。 [03:26.26]since the turn of the century. [03:28.55]自本世紀(jì)初以來 [03:30.83]In the face of all these facts, [03:33.26]那些國家面對所有這些事實 [03:35.69]it seems senseless for countries to continuedestroying their rainforests. [03:39.52]仍然繼續(xù)毀滅它們的雨林， [03:43.35]However, the problem is not so simple. [03:45.97]這是遇蠢的。 [03:48.60]The countries in which the rainforests are located are all [03:51.58]雨林所在的國家非常窮， [03:54.55]quite poor and overpopulated. [03:57.04]人口過多， [03:59.52]One of them, Brazil, has a population of 140 million, [04:03.15]其中之一的巴西就有1。4億人口， [04:06.78]about half of whom are living in absolute poverty. [04:09.81]差不多一半的人生活在絕對貧困狀態(tài)之中。 [04:12.84]The governments in these countries are usually also too weak [04:16.03]這些國家的政府往往太弱， [04:19.21]to stop large companies and powerful individuals [04:22.30]無法制止大公司和有權(quán)勢 [04:25.38]from destroying the rainforests. [04:27.90]的個人毀壞森林。 [04:30.42]They have no money, so when the poor whom they cannot feed [04:33.91]政府沒有錢，所以當(dāng)那些政府 [04:37.39]find work cutting down treesor burning forestland, [04:40.48]無法養(yǎng)活的窮人找到砍伐的工作或者燒毀林地的工作時， [04:43.56]the governments often have no choice but to turn a blind eye [04:47.19]它們常常別無選擇，只能視而不見。 [04:50.82]Moreover, for many of these countries, [04:53.64]此外，對多數(shù)這類國家來說， [04:56.46]the valuable timber and other resources found in the rainforests [04:59.79]雨林中發(fā)現(xiàn)的珍貴木材和 [05:03.12]are also a very important source of foreign exchange, [05:06.31]其他資源還是外匯的重要來源。 [05:09.50]which they badly need to pay off their foreign debts [05:12.42]它們迫切需要這些外匯來償還外債， [05:15.35]and purchase foreign equipment and other goods. [05:18.18]購買外國設(shè)備及其他貨物。 [05:21.02]The only solution to the problem, then, [05:23.84]然而解決問題的唯一辦法 [05:26.66]seems to befor the richer countries of the world [05:29.53]看來要靠世界上富有的國家 [05:32.41]to help the countries where the rainforests are located. [05:35.49]幫助熱帶雨林所在的國家。 [05:38.57]One way they could help would beby cancelling the international debts [05:42.44]它們可以幫助的一個辦法是，取消像巴西這樣國家所欠的國際債務(wù)， [05:46.31]that countries like Brazil owe, [05:48.42]仍與這些國家共同努力 [05:50.54]while also working together with these countriesto solve their other economic problems. [05:54.61]解決它們其它的經(jīng)濟問題。 [05:58.69]At the same time, they could suppores to teach the local people [06:02.37]與此同時，他們還應(yīng)支持一個計劃， [06:06.05]to regard the rainforests as gardens to be harvested, [06:09.74]教當(dāng)?shù)厝税延炅忠曌髂軌蚴斋@的花園， [06:13.42]and not merely as places where the only way for themto make a living [06:16.86]不要只看成他們謀生的唯一地方 [06:20.29]is by senselessly cutting down trees and burning [06:23.22]一味愚頑地砍伐焚毀。 [06:26.14]Such programmes could teach the local people how to select trees worth exporting [06:30.56]這些計劃可以教會本地人只選擇值得出口的樹木來砍伐， [06:34.97]and to cut only those trees downwhile leaving the rest, [06:38.55]而留下其它樹木， [06:42.13]so that the basic make-up of the forest would not be disturbed. [06:45.76]這樣森林的基本構(gòu)成不會受干擾。 [06:49.39]This would also mean [06:51.36]這同樣意味著 [06:53.34]that the environment needed for the survival of the many rare species of animals and plants [06:57.36]著許多稀有種類的動物、植物 [07:01.38]as well as of the Indian tribes that live in the rainforest could be preserved. [07:05.70]和居住在雨林的印地安人部落都可以得到保護。 [07:10.03]The local people could also be taught to earn more money [07:12.97]教會當(dāng)?shù)厝送ㄟ^砍伐選定的樹種、 [07:15.91]by cutting the selected trees and making them into furniture on the spot. [07:19.63]就地制成家具來掙更多的錢。 [07:23.35]In addition, they could learn how to harvest other valuable natural materials [07:27.48]此外，他們能學(xué)會如何獲取 [07:31.60]that are now being wasted, [07:33.63]其它正在浪費的寶貴自然資源， [07:35.65]and sell them overseas to earn foreign exchange for their countries [07:39.34]向海外銷售為國家換取外匯。 [07:43.02]Last but not least, people in the richer countries of the world [07:46.40]最后同樣重要的是：世界上的富裕國家 [07:49.79]could also help save the rainforests [07:52.46]可以更精心使用紙張一類源自木材的源產(chǎn)品， [07:55.14]by using wood-derived products such as paper more carefully [07:58.67]也可以回收廢紙產(chǎn)品以減少對新伐樹木的需求， [08:02.19] and by recycling used paper products to help reduce the demand for newly cut wood. [08:07.22]用這些辦法幫助拯救熱帶雨林。 [08:12.25]Life on the tundra [08:14.17]北極凍土帶的生命 [08:16.09]Tundra is the name given to the low,marshy plains of Europe, [08:19.07]凍土帶是給歐洲、西伯利亞、 [08:22.05]SiliCa, and North America that border on the Arctic Ocean. [08:25.08]北美等瀕臨北冰洋的低洼沼澤平原的命名。 [08:28.11]In Alaska, the vast, cold region known as the "Northern Slope" [08:31.60]在阿拉斯加，被稱為北坡的廣闊寒冷地帶 [08:35.08]is part of the tundra. [08:36.75]就是凍土帶的一部分。 [08:38.43]Nature sets harsh terms for survival in thins land [08:41.16]大自然為這片土地設(shè)置的生存條件十分嚴(yán)酷， [08:43.89]only those plants and animals [08:45.66]只有那些能適應(yīng)惡劣環(huán)境的植物和動物 [08:47.44]that are adapted to the hostile environment can survive in it. [08:50.38]才能在這里生存。 [08:53.32]Long periods of darkness and bitter cold [08:55.59]長時間的黑暗和嚴(yán)寒 [08:57.86]are the major threats to life on the tundra. [09:00.20]是這一地帶生命的主要威脅。 [09:02.54]At the Arctic Circle, [09:04.46]在北極圈， [09:06.38]the sun cannot be seen above the horizon in December [09:09.16]在12月，無法見到太陽升出地平線。 [09:11.94]North of the Circle, the darkness lasts even longer. [09:14.62]極圈以北黑暗延續(xù)更長。 [09:17.30]Over the northern reaches of the tundra, [09:19.63]凍土帶的北部邊緣以外， [09:21.97]no sunlight can be seen at all for several months of the year? [09:24.49]一年中甚至有好幾個月根本見不到太陽。 [09:27.01]The darkness is balanced, to some degree [09:29.20]在某種程度上說， [09:31.38]by Continuous daylightduring the summer months. [09:33.74]黑暗被連續(xù)不斷的夏季白晝抵消了。 [09:36.10]But even in the warrmest month, [09:37.84]但即使在最溫暖的冬季月份， [09:39.58]the temperature only averages about 50 degrees F (10 degrees C). [09:43.16]氣溫的平均值才為大約50華氏度（10攝氏度）。 [09:46.74]During the dark winter months the average temperature falls to - 16 degrees [09:50.42]在黑暗的冬季月份里，平均氣溫下降至零下16華氏度 [09:54.10](-27 degrees C), [09:56.44]（零下27攝氏度）， [09:58.78]and sometimes to -40 degrees (C and F) and below. [10:02.64]有時到零下40度（攝氏與華氏），甚至更低。 [10:06.51]Because of the intense cold, [10:08.63]由于嚴(yán)寒， [10:10.74]the subsoil of the tundraremains permanently frozen to a great depth. [10:14.13]凍土帶的下層土壤長久凍結(jié)很深。 [10:17.51]During the brief summer, [10:19.43]在短暫的夏季， [10:21.35]a few feet (about a meter) of soilthaw at the surface. [10:24.52]幾英尺（大約一米）厚的土地只是表層解凍， [10:27.70]It is this thin layer of active soil [10:29.81]就是這層薄薄的活土地支持著 [10:31.93]that supports all living things on the tundra. [10:34.25]凍土帶所有的生命。 [10:36.58]For nine months of the year, [10:38.35]一年之中長達9個月， [10:40.13]the tundra is a dark,seemingly lifeless wild land: [10:42.95]凍土帶一片黑暗，看上去像沒有生命的荒野地。 [10:45.77]Then in Juhe,as if by magic, [10:47.90]不過，到了6月份， [10:50.03]a never-setting summet sun' [10:51.91]如同變魔太一般，一個永不落山的夏季太陽 [10:53.79]gives birth to hurtdreds of speciesof arctic plants to cover the ground. [10:56.91]給數(shù)百種北極植物以生命，使之覆蓋大地。 [11:00.04]A plant that grows more than three feet [11:02.36]長勢超過3英尺 [11:04.69] (about a meter)is unusual on the tundra. [11:07.10]（約1米）高的植物在凍土帶十分罕見。 [11:09.52]There are no tall trees. [11:11.24]沒有高樹， [11:12.97]The frozen subsoil prevents rootsfrom growing deep enough to support them. [11:16.00]凍結(jié)的下層土壤阻礙樹根向足夠的深層生長來供給高樹營養(yǎng)。 [11:19.03]By the end of August the breath of winter returns [11:21.67]到8月底，冬天的氣息重返凍土帶， [11:24.30]and by mid-September the tundra is white again. [11:26.88]到9月中旬凍土地又是白茫茫一片。 [11:29.45]The animal life on the tundra is unusually rich [11:31.83]動物的生活在凍土帶異乎尋常地豐富多彩。 [11:34.20]for an environment that seems so harsh. [11:36.49]對于顯得如此惡劣的環(huán)境來說， [11:38.78] Herds of arctic deer move from place to place in search of food. [11:41.81]成群的北極鹿為了尋找食物從一個地方遷徙至另一個地方， [11:44.84]Bands of wolves follow them and hunt for the weak or sick ones. [11:47.96]狼群尾隨它們，獵食弱小的或者生病的鹿。 [11:51.08]Few birds actually live on the tundra. [11:53.60]幾乎沒有鳥真正在活在凍土帶。 [11:56.12]However, a variety of birds migrate to nest and feed during the summer. [11:59.36]不過，各種不同的鳥在夏季遷徙到這里做巢捕食。 [12:02.60]The wet, marshy land produces a large number of insects [12:05.38]潮濕的沼澤地產(chǎn)生大量昆蟲 [12:08.16]that provide food for the smaller birds that, [12:10.40]為小鳥提供食物， [12:12.63]in turn, provide food for the arctic fox and the wolf. [12:15.45]而小鳥又為北極狐和狼提供食物。 [12:18.27]The balance of nature is so delicate on the tundra [12:20.49]在凍土帶，自然界的平衡真如此而已微妙， [12:22.71]that even minor disturbances [12:24.79]小小的干擾 [12:26.87]may produce major changes in the environment. [12:29.05]可能產(chǎn)生巨大的環(huán)境變化。 [12:31.23]Any increase or decrease in the population of one species [12:34.01]人口的增加或減少 [12:36.79]may affect all other species on the tundra. [12:39.12]可能會受到其他種類的侵襲，在凍土帶。 [12:41.44]For example,if the number of wolves and foxes decreases, [12:44.26]某一物種如狼的數(shù)量的增加或減少， [12:47.09]the food chain is upset. [12:48.90]食物鏈將失去平衡。 [12:50.72]Without wolves, the number of grazing animals [12:53.20]沒有了狼， [12:55.68]like the deer--would increase. [12:57.65]像鹿一類的食草動物增加， [12:59.62]This increase would result in a food shortage, [13:01.81]鹿的增加會引起食物短缺， [13:03.99]which would cause death to many smaller animals. [13:06.27]這就會直接導(dǎo)致許多小動物的死亡。 [13:08.56]A decrease in the number of these smaller animals [13:10.69]這些小動物數(shù)量的減少， [13:12.82]would in turn decrease the food supply fox the arctic fox and the wolf. [13:15.99]繼而會影響北極狐和北極狼的食物供應(yīng)。 [13:19.16]In this way, the entire food chain might he affected by a changein the numar [13:22.55]就這樣，整個食物鏈可能會受 [13:25.93]of a single species. [13:27.81]任一種動物數(shù)量變化的影響。 [13:29.69]Until recently, the chaning seasons on the tundra [13:32.26]直到最近，凍土帶的季節(jié)變化 [13:34.84]were seen onlyby a few Eskimo hunters and explorers. [13:37.78]只有少數(shù)幾位愛斯基摩獵人和探險者見過。 [13:40.72]What would draw men and women to live in such a hostile land? [13:43.50]什么東西吸引著人們生活在條件這樣惡劣的土地上呢？ [13:46.28]The answer is oil. [13:47.90]答案是石油。 [13:49.52]In 1968, oil was discovered beneath the frozen soilon [13:52.55]1968年，凍土地底下發(fā)現(xiàn)了石油 [13:55.58]Alaska's Northern Slope. [13:57.56]是在阿拉斯加北坡 [13:59.55]Now an 800-mile (about 1300 kilometers) [14:02.23]今天已鋪設(shè)了800英里（約1300公里） [14:04.90]pipeline has been builtfrom Prudhoe Bay on the Arctic Ocean to Valdes, [14:08.43]長的輸油管道從北冰洋的普拉德霍灣 [14:11.96]a port on the south coast of Alaska. [14:14.19]到阿拉斯加南海岸的瓦爾迪茲港。 [14:16.42]The pipeline carries the oil from the Northern Slope [14:19.05]管道把石油從北部的傾斜坡 [14:21.68]across the tundra, to the port. [14:23.71]通過凍土地輸送到港口， [14:25.75]From there, it is shipped to the rest of the United States. [14:28.39]再從那里裝運至美國其它地區(qū)。 [14:31.03]Thousands of men and women were needed to build and maintain the pipeline [14:34.29]需要成千上萬的男男女女來鋪設(shè)和維護輸油管， [14:37.56]For the first time, [14:39.18]第一次 [14:40.80]large numbers of peoplewere brought into contact with the tundra. [14:43.42]如此大量的人們接觸凍土帶， [14:46.05]Their presence and the presence of the pipeline they built [14:48.67]他們的到來和他們建造的輸油管的出現(xiàn) [14:51.30]represented a major change in the environment. [14:53.58]意味著環(huán)境的大改變。 [14:55.87]How will the lifecydes of the tundra be affected? [14:58.14]凍土帶的生命循環(huán)將受到怎樣的影響呢？ [15:00.41]The survival of the United States [15:02.24]美國的生存 [15:04.07]depends on the abilityto find new sources of energy. [15:06.80]依賴于找到新能源的能力。 [15:09.53]Oil from beneath the tundra is very important to the nations' development [15:12.51]凍土帶地下的石油對國家的發(fā)展非常重要。 [15:15.49]But the survival of the tundra [15:17.41]但凍土帶的生存 [15:19.33]depends on how carefully people maintain [15:21.56]要依靠人們小心謹(jǐn)慎 [15:23.79]the delicate balance of nature in this environment. [15:26.42]來維持環(huán)境中的微妙平衡。

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