# Water hyacinth - 科目：雅思听力真题（Part 3） - 考频：中频 - 最近考试：2020.7.31/2019.8.24/2017.11.2 - 题目数：9 - 来源页：https://www.yaquan.site/paper/e097674a-7e5a-4cad-ac98-d11c7c5355cb（在线机考练习与音频请访问该页面） - 数据更新：2026-11-07 ## 题目原文 00:00:00,540 Part three. You will hear two students called Alia and John discussing the research on water hyacinths. First, you have some time to look at questions twenty-one to twenty-six. 00:00:21,980 Now listen carefully and answer questions twenty-one to twenty-six. 00:01:02,620 John, how is it going with your research on water hyacinth? 00:01:07,080 Well, I went on a field trip on my own and collected the primary data. After I came back, I also referred to the published data. 00:01:14,900 So what do you know about this plant? 00:01:18,040 The water hyacinth grows in tropical countries. It has beautiful purple-blue flowers, but everybody hates it. 00:01:24,700 Why is that? 00:01:26,000 The water hyacinth, as the world's worst invasive aquatic plant, has attracted significant attention. Millions of these plants grow in rivers and lakes and have brought huge environmental and cultural problems to the local people. Farmers cannot travel in boats on the water and thus cannot fish in it. In addition, heavy free-floating mats of water hyacinth are clogging the dam at the power station in West Africa. Turbines of the power station are often shut down because of the intertwined leaves. Dams often cease to function as a result, severely restricting the electricity generation. Dense mats of water hyacinth also shade the surface and prevent algae growth, thus limiting the production of oxygen and threatening the survival of fish. 00:02:06,720 So where did water hyacinth originate from? 00:02:10,420 The water hyacinth is native to the Amazon basin in Latin America. It has spread mainly to the tropics and subtropics from much of the world since the eighteen hundreds. Later, it was introduced into Europe and Africa as an ornamental garden pond plant due to its beauty. Flowers of this plant were being sold in local markets in African countries as a source of income for women. Since the nineteen hundreds, this weed has infested lakes, rivers, and creeks of the delta areas in West Africa. 00:02:39,340 I guess whoever introduced this plant had never expected the disastrous impact it would have on the local ecological environment. What kind of habitat does water hyacinth thrive most in? 00:02:52,680 Well, it has been discovered that the nutrient-rich environment contributes significantly to the rapid proliferation of this weed, which obtains its nutrients directly from the water. This is normally compounded with a decrease of nutrients along the riverbanks. 00:03:06,360 Why is that? 00:03:07,680 The main reason for soil nutrient loss is that local residents cut down trees. Excessive deforestation accelerates soil erosion, which indirectly compound this issue. Without enough trees to retain nutrients in the soil, frequent rain might partly aggravate this by carrying some of the nutrients into the waterways. 00:03:25,640 Are there any effective measures to control or even eradicate this weed? 00:03:31,440 Yes, a number of approaches have been widely applied throughout the world. Among them, biological control is the most widely favored long-term control method by introducing a type of insect that feeds on the water hyacinth. So far, Nigeria has used this method for six months. However, the water hyacinth won't be removed in immediately. The side effects of this method on local ecology will remain unforeseen for years because it takes time for this external insect species to reach a density sufficient enough to affect ecological development. 00:04:03,320 Then what about other approaches? Is there a quicker way to control it? 00:04:08,380 Well, the mechanical removal of water hyacinth is seen as the best short-term solution. This option includes harvesting plants and inside cutting. This method can immediately open physical space for fish and boat traffic. It is, however, inefficient for workers to process extensive areas and costly to use large cutting and dredging equipment. Ironically, it costs even more to dispose of this plant than to remove it. 00:04:34,900 Before you hear the rest of the discussion, you have some time to look at questions twenty-seven to thirty. 00:04:52,960 Now listen and answer questions twenty-seven to thirty. 00:05:09,840 Can we make use of this weed and turn it into something good? 00:05:14,460 Now, scientists think that water hyacinth can be useful. The plant itself, although more than ninety-five percent water, has a fibrous tissue and a high energy and protein content and can be used for a variety of useful applications. 00:05:26,720 So what do people do with water hyacinth that is initially removed? 00:05:32,020 First, the cut-down water hyacinth is left to dry under the sun for a few days before being mixed with ash and animal manure. The mixture can be used as alternative soil rather than fertilizer. It can grow crops with increased yield. 00:05:45,020 That sounds interesting. 00:05:46,920 Mushroom farmers can benefit from water hyacinth as well. Using the mixture mentioned earlier, mushrooms generally grow much faster so that farmers can harvest mushrooms sooner, which enables them to make money faster. 00:05:58,880 I see. It can be used to grow oyster and straw mushrooms, right? 00:06:03,820 Yes. In India, attempts have been made to grow these types of edible mushrooms organically utilizing water hyacinth. These mushrooms provide sufficient nutritional values, including minerals and high quality protein, which are essential to people's level of fitness. 00:06:18,380 Right. Are there any other measures taken to utilize water hyacinth? 00:06:23,680 In Southeast Asia, people feed cows using chopped water hyacinth mixed with other vegetables. Then the waste from the cows is treated to produce methane gas, which can be used as fuel for cooking, lighting, or powering an engine. And with global warming getting worse, developing alternative sources of energy will be more urgent than ever. 00:06:42,300 Maybe in the future, people will love water hyacinth instead of hating it. 00:06:47,780 Yes, that's very likely if we can make full use of this weed. 00:06:54,100 That is the end of part three. You now have thirty seconds to check your answers to part three. ## 题目与答案 ### 21-22. 21-22 Which TWO problems are caused by water hyacinth? 21-22 Which TWO problems are caused by water hyacinth? - plants and fish are poisoned. - farmers cannot fish. - the dam`s structure is damaged. - electricity production is affected. **答案**：farmers cannot fish.,electricity production is affected. 原文定位：Farmers cannot travel in boats on the water and thus cannot fish in it. In addition, heavy free‑floating mats of water hyacinth are clogging the dam at the power station in West Africa. Turbines of the power station are often shut down because of the intertwined leaves. Dams often cease to function as a result, severely restricting the electricity generation 同义替换：「production」↔「generation」；「affected」↔「restricted」 ### 23. 23 Where was water hyacinth originally from? 23 Where was water hyacinth originally from? - Latin America - Africa - Europe **答案**：Latin America 原文定位：The water hyacinth is native to the Amazon basin in Latin America. It has spread mainly to the tropics and subtropics from much of the world since the eighteen hundreds. Later, it was introduced into Europe and Africa as an ornamental garden pond plant due to its beauty 同义替换：「originally」↔「native」；「Latin America」↔「Latin America」 ### 24. 24 What is the primary cause of the decrease in nutrients from the soil? 24 What is the primary cause of the decrease in nutrients from the soil? - soil erosion - a change of rainfall - loss or trees **答案**：loss or trees 原文定位：The main reason for soil nutrient loss is that local residents cut down trees 同义替换：「primary cause」↔「main reason」；「decrease」↔「loss」；「loss of trees」↔「deforestation」 ### 25. 25 When will the biological solution bring risks to the environment? 25 When will the biological solution bring risks to the environment? - immediately - 6 months later - many years later **答案**：many years later 原文定位：The side effects of this method on local ecology will remain unforeseen for years because it takes time for this external insect species to reach a density sufficient enough to affect ecological development ### 26. 26 What does John say about the mechanical solution? 26 What does John say about the mechanical solution? - ineffective - dangerous - expensive **答案**：expensive 原文定位：Well, the mechanical removal of water hyacinth is seen as the best short-term solution. This option includes harvesting plants and inside cutting. This method can immediately open physical space for fish and boat traffic. It is, however, inefficient for workers to process extensive areas and costly to use large cutting and dredging equipment 同义替换：「expensive」↔「costly」；「mechanical solution」↔「mechanical removal」 ### 27. dried water hyacinth dried water hyacinth - can reduce the effect of global warming. - can be used an alternative energy resource. - can make quick profits. - can produce materials for plants to grow in. - can be good for human health. - can produce fertilizer. **答案**：can produce materials for plants to grow in. 原文定位：water hyacinth is left to dry under the sun for a few days before being mixed with ash and animal manure. The mixture can be used as alternative soil rather than fertilizer. It can grow crops with increased yield 同义替换：「dried」↔「left to dry under the sun」；「can produce materials for plants to grow in」↔「used as alternative soil」 ### 28. mushroom farmers mushroom farmers - can reduce the effect of global warming. - can be used an alternative energy resource. - can make quick profits. - can produce materials for plants to grow in. - can be good for human health. - can produce fertilizer. **答案**：can make quick profits. 原文定位：Mushroom farmers can benefit from water hyacinth as well. Using the mixture mentioned earlier, mushrooms generally grow much faster so that farmers can harvest mushrooms sooner, which enables them to make money faster 同义替换：「make quick profits」↔「make money faster」；「mushroom farmers」↔「Mushroom farmers」 ### 29. oyster and straw mushrooms oyster and straw mushrooms - can reduce the effect of global warming. - can be used an alternative energy resource. - can make quick profits. - can produce materials for plants to grow in. - can be good for human health. - can produce fertilizer. **答案**：can be good for human health. 原文定位：Yes. In India, attempts have been made to grow these types of edible mushrooms organically utilizing water hyacinth. These mushrooms provide sufficient nutritional values, including minerals and high quality protein, which are essential to people's level of fitness 同义替换：「good for human health」↔「nutritional values」；「mushrooms」↔「mushrooms」 ### 30. cows cows - can reduce the effect of global warming. - can be used an alternative energy resource. - can make quick profits. - can produce materials for plants to grow in. - can be good for human health. - can produce fertilizer. **答案**：can be used an alternative energy resource. 原文定位：In Southeast Asia, people feed cows using chopped water hyacinth mixed with other vegetables. Then the waste from the cows is treated to produce methane gas, which can be used as fuel for cooking, lighting, or powering an engine. And with global warming getting worse, developing alternative sources of energy will be more urgent than ever 同义替换：「cows」↔「cows」；「alternative energy resource」↔「alternative sources of energy」 --- 以上内容由鸭圈雅思真题库（www.yaquan.site）提供，收录近期雅思考试真题回忆，支持在线机考模式免费练习。