Oxygen trends in the Galactic thin and thick disks

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2024年统招专升本英语考试真题及答案

2024年统招专升本英语考试真题及答案

2024年统招专升本英语考试真题及答案全文共3篇示例,供读者参考篇1Title: 2024 National Unified Entrance Examination English Exam Questions and Answers for Part-time UndergraduatesIntroduction:The National Unified Entrance Examination for part-time undergraduates is a key milestone for individuals looking to further their education through specialized programs. In 2024, the English exam questions have been carefully crafted to assess candidates' language proficiency and comprehension skills. In this document, we will provide a comprehensive overview of the exam questions and answers for aspiring part-time undergraduates.Section 1: Reading Comprehension (45 points)Question 1:Read the following passage and answer the questions below:"Climate change is one of the most pressing issues facing our planet. Rising temperatures, extreme weather events, andmelting ice caps are all signs of the impact of human activities on the environment. To combat climate change, we must take action now by reducing our carbon footprint, investing in renewable energy sources, and promoting sustainable practices."Question 1.1: What are some of the signs of climate change mentioned in the passage?Question 1.2: What are three ways mentioned in the passage to combat climate change?Answers:1.1: Rising temperatures, extreme weather events, and melting ice caps are signs of climate change.1.2: Reducing our carbon footprint, investing in renewable energy sources, and promoting sustainable practices are ways to combat climate change.Question 2:Read the following passage and answer the questions below:"Artificial intelligence (AI) is revolutionizing various industries by improving efficiency, accuracy, and innovation. From autonomous vehicles to medical diagnostics, AI has the potential to transform how we live and work. However, concernsabout AI ethics, privacy, and job displacement have also emerged."Question 2.1: What are some benefits of artificial intelligence mentioned in the passage?Question 2.2: What are some concerns related to artificial intelligence mentioned in the passage?Answers:2.1: Improving efficiency, accuracy, and innovation are benefits of artificial intelligence.2.2: Concerns about AI ethics, privacy, and job displacement are mentioned in the passage.Section 2: Writing (30 points)Question 1:Write an essay of at least 300 words on the following topic: "The Importance of Lifelong Learning in a Globalized World."Answer: (Sample essay)In today's globalized world, the pace of change and innovation is ever-accelerating, making lifelong learning more crucial than ever before. Lifelong learning is the process ofacquiring new knowledge and skills throughout one's life, enabling individuals to adapt to new challenges and opportunities. This continuous pursuit of learning not only enhances personal growth but also contributes to individual and societal success.One of the key benefits of lifelong learning is its ability to enhance personal development and career advancement. In a rapidly changing job market, individuals who prioritize lifelong learning are better equipped to acquire new skills, stay relevant in their fields, and seize opportunities for growth. Lifelong learners are also more adaptable and resilient in the face of technological advancements and economic shifts, making them valuable assets in the workforce.Moreover, lifelong learning promotes intellectual curiosity, creativity, and critical thinking skills. By engaging in lifelong learning activities such as reading, attending workshops, or pursuing further education, individuals can expand their knowledge base, stimulate their minds, and foster a culture of innovation. In a globalized world where creativity and problem-solving are highly valued, lifelong learners are more likely to contribute to the advancement of society and address complex challenges.In conclusion, lifelong learning plays a vital role in empowering individuals to thrive in a globalized world. By embracing a mindset of continuous growth and development, individuals can adapt to change, expand their horizons, and contribute to a more prosperous and sustainable future for all. Embracing lifelong learning is not only a personal choice but a societal imperative in today's dynamic and interconnected world.Section 3: Listening Comprehension (25 points)Instructions: Listen to the audio clips and answer the questions below.Question 1: (Audio clip)What is the speaker talking about?Answers: (based on audio content)The speaker is discussing the benefits of volunteering and its impact on communities.Question 2: (Audio clip)What are the speaker's recommendations for effective time management?Answers: (based on audio content)The speaker recommends setting priorities, delegating tasks, and using technology to manage time effectively.Conclusion:The 2024 National Unified Entrance Examination forpart-time undergraduates includes a comprehensive assessment of candidates' English language skills through reading comprehension, writing, and listening exercises. By familiarizing themselves with the exam questions and answers provided in this document, aspiring part-time undergraduates can prepare effectively for the exam and enhance their chances of success. Good luck to all candidates!篇22024年统招专升本英语考试真题及答案Section I Listening Comprehension (30 points)Part A (10 points)Directions: In this part, you will hear ten short dialogues. At the end of each dialogue, a question will be asked about what was said. Both the dialogue and the question will be spoken only once. After you hear a dialogue and the question about it, readthe four possible answers on your paper, and decide which one is the best answer to the question you have heard.1. What does the woman want?A. A glass of water.B. A cup of tea.C. Some coffee.D. A bottle of soda.2. How is the man feeling now?A. Nervous.B. Excited.C. Upset.D. Satisfied.3. What is the woman looking for?A. Her keys.B. Her phone.C. Her wallet.D. Her glasses.4. What did the woman forget to bring?A. Her umbrella.B. Her ID card.C. Her lunch.D. Her purse.5. What time will the meeting start?A. At 8:30.B. At 9:00.C. At 9:30.D. At 10:00.6. How will the man get to the airport?A. By taxi.B. By bus.C. By car.D. By subway.7. What is the woman’s job?A. A teacher.B. A doctor.C. A lawyer.D. An accountant.8. When is the woman’s birthday?A. In January.B. In February.C. In March.D. In April.9. What is the man’s favorite food?A. Pizza.B. Sushi.C. Pasta.D. Hamburger.10. Why is the man calling the woman?A. To make an appointment.B. To cancel a meeting.C. To ask for directions.D. To say thank you.Part B (10 points)Directions: In this part, you will hear two passages. At the end of each passage, you will hear five or six questions. Both the passage and the questions will be spoken only once. After you hear a question, read the four possible answers on your paper, and decide which one would be the best answer to the question you have heard.Passage OneQuestions 11-1511. What is the speaker’s favorite hobby?A. Reading books.B. Watching movies.C. Playing sports.D. Traveling.12. How does the speaker feel about music?A. She enjoys it.B. She dislikes it.C. She is indifferent.D. She hates it.13. What does the speaker say about her job?A. It is boring.B. It is stressful.C. It is rewarding.D. It is flexible.14. What does the speaker do in her free time?A. Hang out with friends.B. Volunteer at a charity.C. Go to the gym.D. Paint pictures.15. What book does the speaker recommend?A. The Great Gatsby.B. Pride and Prejudice.C. To Kill a Mockingbird.D. Harry Potter.Passage TwoQuestions 16-2016. What is the passage mainly about?A. The benefits of exercise.B. The importance of healthy eating.C. The dangers of smoking.D. The effects of stress.17. How many hours of sleep is recommended for adults?A. 5-6 hours.B. 7-8 hours.C. 9-10 hours.D. 11-12 hours.18. What is the speaker’s advice on diet?A. Skip breakfast.B. Eat fast food.C. Avoid sugar.D. Drink soda.19. What does the speaker suggest for reducing stress?A. Taking a vacation.B. Watching TV.C. Working longer hours.D. Sleeping less.20. What is the speaker’s final advice?A. Exercise regularly.B. Eat more vegetables.C. Quit smoking.D. Meditate daily.Section II Use of English (20 points)Directions: Read the following text. Choose the best word(s) for each numbered blank and mark A, B, C, or D on your answer sheet.Since the invention of the smartphone, many people have become 21 on social media. It is not uncommon to see individuals completely immersed in their phones, 22 to the world around them. This behavior can have negative consequences for one’s social life. Instead of having face-to-face interactions,people are opting for virtual 23, which can lead to feelings of loneliness and isolation.Moreover, the excessive use of social media can impact one’s mental health. The constant need for validation 24 likes and comments can make individuals anxious and even depressed. Studies have shown that heavy social media users are more likely to experience 25 levels of anxiety and stress compared to those who use social media sparingly.It is important to remember that social media is a tool, not a substitute for real-life connections. While it can be a useful platform for staying in touch with friends and family, it should not be the sole means of communication. 26, it is essential to set boundaries and prioritize face-to-face interactions to maintain healthy relationships and mental well-being.21. A. addicted B. dependent C. fascinated D. obsessed22. A. oblivious B. unaware C. indifferent D. clueless23. A. discussions B. conversations C. exchanges D. dialogues24. A. on B. by C. for D. with25. A. high B. elevated C. increased D. heightened26. A. In addition B. On the contrary C. Therefore D. FurthermoreSection III Reading Comprehension (40 points)Part A (10 points)Directions: Read the following passage and answer the questions that follow.The Benefits of Outdoor ExerciseSpending time outdoors has numerous benefits for both physical and mental health. One of the main advantages of outdoor exercise is the exposure to natural sunlight, which allows the body to absorb vitamin D. This essential nutrient plays a key role in bone health and immune function.Additionally, outdoor activities such as hiking, biking, and jogging provide an opportunity to connect with nature and reduce stress levels. Research has shown that spending time in green spaces can improve mood and cognitive function.Furthermore, outdoor exercise can increase motivation and engagement compared to indoor workouts. The variety of terrains and the changing scenery can make workouts more enjoyable and challenging.27. What is one of the benefits of outdoor exercise mentioned in the passage?A. Improved heart healthB. Enhanced creativityC. Increased vitamin C absorptionD. Better immune function28. According to the passage, how can spending time outdoors reduce stress levels?A. By increasing exposure to natural sunlightB. By engaging in physical activitiesC. By consuming vitamin D supplementsD. By avoiding indoor environments29. Which of the following activities is NOT mentioned as an outdoor exercise in the passage?A. SwimmingB. HikingC. BikingD. Jogging30. How does outdoor exercise differ from indoor workouts, according to the passage?A. It requires less motivationB. It offers less varietyC. It is more engagingD. It is less challengingPart B (30 points)Directions: Read the following passages. Answer the questions according to the information given in the passages.Passage OneThe Impact of Climate ChangeClimate change is a global issue that poses significant threats to the planet. The rise in average global temperatures has led to extreme weather events such as hurricanes, droughts, and wildfires. These environmental disasters have devastating consequences for ecosystems, wildlife, and human populations.In addition to the immediate impacts of climate change, there are long-term effects that will have lasting repercussions. Rising sea levels, melting ice caps, and ocean acidification are allcontributing to the decline of biodiversity and the destruction of natural habitats.It is essential for governments, industries, and individuals to take action to combat climate change and reduce carbon emissions. Sustainable practices, renewable energy sources, and conservation efforts are crucial in mitigating the effects of global warming.31. What are some of the extreme weather events caused by climate change mentioned in the passage?A. Floods and blizzardsB. Earthquakes and tsunamisC. Hurricanes and droughtsD. Tornadoes and heatwaves32. What are some of the long-term effects of climate change discussed in the passage?A. Volcanic eruptions and landslidesB. Biodiversity decline and habitat destructionC. Disease outbreaks and water contaminationD. Deforestation and soil erosion33. According to the passage, what is needed to combat climate change?A. Increased carbon emissionsB. More natural disastersC. Sustainable practices and conservation effortsD. Deforestation and pollutionPassage TwoThe Benefits of BilingualismResearch has shown that being bilingual has numerous cognitive benefits. Bilingual individuals have been found to have improved problem-solving skills, better multitasking abilities, and enhanced creativity compared to monolingual speakers.Furthermore, being bilingual can delay the onset ofage-related cognitive decline and reduce the risk of neurodegenerative diseases such as Alzheimer's. The constant need to switch between languages and juggle linguistic rules can keep the brain active and agile.In addition to cognitive advantages, bilingualism can also provide social and cultural benefits. Bilingual individuals have theopportunity to communicate with a wider range of people and access different cultures and perspectives.34. According to the passage, what are some cognitive benefits of being bilingual?A. Enhanced problem-solving skillsB. Improved memory recallC. Increased vocabulary sizeD. Better physical coordination35. How can being bilingual help reduce the risk of neurodegenerative diseases?A. By improving social skillsB. By increasing creativityC. By delaying cognitive declineD. By enhancing problem-solving abilities36. What social and cultural benefits are associated with bilingualism, as mentioned in the passage?A. Increased isolation and exclusionB. Limited communication opportunitiesC. Access to a wider range of people and culturesD. Narrowed perspectives and viewpointsSection IV Writing (30 points)Directions: Write an essay of about 200-300 words on the following topic. You should base your essay on the information given in the outline below.Topic: The Importance of Lifelong LearningOutline:1. Introduction- Definition of lifelong learning- Importance of acquiring new knowledge and skills throughout life2. Benefits of lifelong learning- Personal development and growth- Career advancement and job satisfaction- Improved cognitive function and mental well-being3. Ways to engage in lifelong learning- Formal education programs- Online courses and workshops- Self-study and reading4. Conclusion- Recap of the importance of lifelong learning- Encouragement for individuals to pursue continuous learning opportunitiesRemember to organize your ideas logically and support your essay with relevant examples.The above essay must be structured and written in proper English, demonstrating a clear understanding of the topic and presenting a coherent argument. Good luck with your essay!Overall, the 2024 English exam for the Specialized Undergraduate Program is designed to test your listening, reading, comprehension, and writing skills in English. By preparing thoroughly and practicing consistently, you can improve your performance and achieve success on the exam. Best of luck with your studies and exam preparation!篇32024 National Unified Entrance Examination for Junior College English ExaminationPart I Listening Comprehension (30 points)Section ADirections: In this section, you will hear 8 short conversations and 2 long conversations. At the end of each conversation, one or more questions will be asked about what was said. Both the conversation and the questions will be spoken only once. After each question, there will be a pause. During the pause, you must read the four choices marked A), B), C) and D), and decide which is the best answer. Then mark the corresponding letter on Answer Sheet 1 with a single line through the centre.1. A) The man will book a hotel room for the woman.B) The woman will borrow the man's car.C) The man will take the woman to the airport.D) The woman will drive to the airport.2. A) Reading a book.B) Writing an e-mail.C) Watching TV.D) Having dinner.Section BDirections: In this section, you will hear 3 short passages. At the end of each passage, you will hear some questions. Both the passage and the questions will be spoken only once. After you hear a question, you must choose the best answer from the four choices marked A), B), C) and D). Then mark the corresponding letter on Answer Sheet 1 with a single line through the centre.Passage OneQuestions 11 to 13 are based on the passage you have just heard.11. A) It's 20 dollars.B) It's 21 dollars.C) It's 19 dollars.D) It's 18 dollars.12. A) Take the elevator to the 10th floor.B) Walk straight ahead and take the elevator to the 8th floor.C) Take the stairs to the 8th floor.D) Walk straight ahead and take the elevator to the 10th floor.13. A) He is a journalist.B) He is an engineer.C) He is a taxi driver.D) He is a tour guide.Passage TwoQuestions 14 to 16 are based on the passage you have just heard.14. A) To review what they learned.B) To review what they missed.C) To learn history.D) To know if they can miss class.15. A) Because they can't pay much.B) Because it's too difficult for them.C) Because they don't have time to study.D) Because they don't see the point of it.16. A) Studying the history of American economics.B) American political economy.C) Where to put the roots of democratic society.D) The political economy of America.Passage ThreeQuestions 17 to 20 are based on the passage you have just heard.17. A) 18-month-old.B) 21-month-old.C) 24-month-old.D) 27-month-old.18. A) Everywhere.B) In a small space.C) In a large space.D) At a desk.19. A) 4000 vocabulary words.B) 3000 vocabulary words.C) More than 3000 vocabulary words.D) At least 3000 vocabulary words.20. A) Parents.B) Teachers.C) Other children.D) Everybody.Part II Reading Comprehension (40 points)Section ADirections: In this section, there is a passage with ten questions or incomplete statements. Read the passage carefully. Then answer the questions or complete the statements in the fewest possible words (not exceeding 10 words). Mark your answers on Answer Sheet 1.2019 research study discussed work-life balance ___women aged 25-54.Are American women feeling the challenging feelings?The study explains that women may struggle due to ____family responsibilities.Parents are given more _____ than non-parents.The study found the majority result _______ about achieving a balance.A balance requires personal strategies as well as _____ strategies.Flexible work hours and ____ are linked to work-life balance.The study recommends increasing fair _____ and flexibility.In the extension of family benefits to all employed, the balance requires the employer to _____.Women are advised to prioritize activities that would bring ___.Sleep, not leisure, ______ the stress levels of the subjects.The author's suggestion for helping women is to ______.Section BDirections: In this section, there are four passages. Each passage is followed by several questions or unfinished statements. For each of them, there are four choices marked A), B), C) and D). Choose the one that fits best according to the information in the passage you have just read. Mark your answers on Answer Sheet 1.Passage OneQuestions 21 to 25 are based on the passage you have just heard.21. According to the passage, what product is in high demand?A) white sugarB) organic foodC) soft drinksD) vegetables and soybeans22. What is a new development in the food market?A) Only the wealthy can afford organic food.B) Traditional food is becoming less popular.C) The market for natural food is growing rapidly.D) Supermarkets are selling less organic food.23. Why are consumers buying organic food?A) for the low priceB) for the improved qualityC) for the fresh tasteD) for the popular brands24. What has a big influence on consumers' choices?A) the size of the food marketB) the origin of the productsC) the price of the foodD) the quality of the products25. What can consumers find in supermarkets now?A) less sugarB) less plastic packagingC) more unnatural ingredientsD) more organic products......(To be continued)。

新高考英语题型精析精练与话题拓展:话题拓展03.气候变化(解析版)

新高考英语题型精析精练与话题拓展:话题拓展03.气候变化(解析版)

03.气候变化养成良好的答题习惯,是决定高考英语成败的决定性因素之一。

做题前,要认真阅读题目要求、题干和选项,并对答案内容作出合理预测;答题时,切忌跟着感觉走,最好按照题目序号来做,不会的或存在疑问的,要做好标记,要善于发现,找到题目的题眼所在,规范答题,书写工整;答题完毕时,要认真检查,查漏补缺,纠正错误。

一、阅读理解1Rough temperature records from December have yet to be finalized, climate scientists at the National Oceanic and Atmospheric Administration have found there’s a more than 99%chance that 2023 will have the hottest recorded global average temperature, beating out 2016, the previous leader. The year will be the hottest in 174 years of second-keeping where humans have directly measured the temperature of the planet. It’s also likely to be the hottest in the last 125,000 years, which scientists measure by rebuilding temperature records from physical evidence like tree rings and layers of polar ice that have grown over time.The record-breaking year caused fuel climate-driven disasters around the globe from extreme heat that hit Arizona for weeks to floods in Libya and record-hot oceans that caused coral to bleach (变白) off Florida.Scientists say the extreme temperatures are in line with forecasts (预测) for how the planet will continue to warm. The biggest driver of the heat is the buildup of greenhouse gases in the atmosphere (大气层) from burning fossil fuels (化石燃料). “We know why this is happening,” says Zeke Hausfather, climate scientist at Berkeley Earth, a non-profit organization that studies climate trends. “A year like this would not have occurred without the trillion tons of carbon we’ve put into the atmosphere over the last century.”Even with the chart-topping heat this year, next year could be equally as hot. A strong El Nino has already begun, where ocean temperatures warm up in the eastern Pacific. El Nino years are typically hotter, because a large amount of heat that’s stored in the ocean is sent tothe atmosphere. “There’s absolutely still time to act,” an expert says. “Everything we do to change course today will make things better in the future.”1. What can be inferred from paragraph 1?A. 2016 is likely to have the hottest global temperature.B. The temperature records of 2023 have been finished.C. Humans began to directly measure global temperature 174 years ago.D. Tree rings are bad for recording temperature.2. What is the main reason for the record-breaking heat?A. The lack of fossil fuels.B. The increase of greenhouse gases.C. Corals bleached in the ocean.D. Drivers putting much waste into the air.3. Why could the next year be equally hot according to the text?A. El Niño tends to cool down the atmosphere.B. Ocean pollution leads to a warming Pacific.C. A strong El Niño has begun in the western Pacific.D. A lot of heat stored in the ocean goes into the atmosphere.4. What is the best title for the text?A. 2023 Has Suffered from a Strong El NinoB. 2023 May Be the Hottest Year on RecordC. Climate driven Disasters Influence Daily LifeD. The Ocean Plays a Key Role in Cooling Earth【答案】1. C 2. B 3. D 4. B【解析】本文是一篇说明文。

托福阅读真题第245篇Earth’sAtmosphere(答案文章最后)

托福阅读真题第245篇Earth’sAtmosphere(答案文章最后)

托福阅读真题第245篇Earth’sAtmosphere(答案文章最后)Earth’s AtmosphereParagraph 1: Earth’s atmosphere has changed through time. Compared to the Sun, whose composition is representative of the raw materials from which Earth and other planets in our solar system formed, Earth contains less of some volatile elements, such as nitrogen, argon, hydrogen, and helium. These elements were lost when the envelope of gases, or primary atmosphere, that surrounded early Earth, was stripped away by the solar wind or by meteorite impacts, or both. Little by little, the planet generated a new, secondary atmosphere by volcanic outgassing of volatile materials from its interior.1. In paragraph 1, why does the author state that Earth has less nitrogen, argon, hydrogen, and helium than the Sun?O To argue that these elements were once part of an early atmosphere, which disappearedO To suggest that these elements were drawn into the Sun’s atmosphereO To provide evid ence that Earth’s original atmosphere came primarily from meteoritesO To support the claim that Earth’s atmosphere would have changed even more if it had contained more volatile elements Paragraph 2: Volcanic outgassing continues to be the main process by which volatile materials are released from Earth, although it is now going on at a much slower rate. The main chemical constituent of volcanic gases (as much as 97 percent of volume) is water vapor, with varying amounts of nitrogen, carbon dioxide, and other gases. In fact, the total volume of volcanicgases released over the past 4 billion years or so is believed to account for the present composition of the atmosphere with one important exception: oxygen. Earth had virtually no oxygen in its atmosphere more than 4 billion years ago, but the atmosphere is now approximately 21 percent oxygen.2. According to paragraph 2, the history of volcanic outgassing cannot explain which of the following?O The lack of oxygen in the atmosphere 4 billion years ago O The amount of water vapor in the atmosphere todayO The proportions of nitrogen and carbon dioxide in the atmosphere todayO The present abundance of oxygen in the atmosphereParagraph 3: Traces of oxygen were probably generated in the early atmosphere by the breakdown of water molecules into oxygen and hydrogen by ultraviolet light (a process called photodissociation). Although this is an important process, it cannot begin to account for the present high levels of oxygen in the atmosphere. Almost all of the free oxygen now in the atmosphere originated through photosynthesis, the process whereby plants use light energy to induce carbon dioxide to react with water, producing carbohydrates and oxygen.3. Paragraph 3 suggests which of the following about the process of photodissociation?O It is more common today than it was in the early history of the atmosphere.O It is responsible for only a small amount of the oxygen in the atmosphere today.O It removes trace amounts of oxygen from the atmosphere.O It produces more free oxygen than photosynthesis does.Paragraph 4: Oxygen is a very reactive chemical, so at firstmost of the free oxygen produced by photosynthesis was combined with iron in ocean water to form iron oxide-bearing minerals. The evidence of the gradual transition from oxygen-poor to oxygen-rich water is preserved in seafloor sediments. The minerals in seafloor sedimentary rocks that are more than about 2.5 billion years old contain reduced (oxygen-poor) iron compounds. In rocks that are less than 1.8 billion years old, oxidized (oxygen-rich) compounds predominate. The sediments that were precipitated during the transition contain alternating bands of red (oxidized iron) and black (reduced iron) minerals. These rocks are called banded-iron formations. Because ocean water is in constant contact with the atmosphere, and the two systems function together in a state of dynamic equilibrium, the transition from an oxygen-poor to an oxygen-rich atmosphere also must have occurred during this period.4. Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information.O Since the oceans and the atmosphere function together, the atmosphere must have become oxygen rich during this period.O Because ocean water is in constant contact with the atmosphere, the two systems maintain a dynamic equilibrium.O The transition to an oxygen-rich atmosphere could not have happened without constant contact with the oceans.O Much of the oxygen in the oceans must have been pulled out of the atmosphere during this period.5. According to paragraph 4, what can be learned from the type of iron compounds in seafloor rocks?O How the process of photosynthesis has changed over time O The level of oxygen in the water at a certain time in history O How levels of iron in ocean water decreased over timeO The overall mineral content of the ocean water6. According to paragraph 3, banded-iron formations are found in what kind of rocks?O Those that are more than 2.5 billion years oldO Those that do not contain oxidized compoundsO Those that are from a transitional period in terms of oxygen richnessO Those that are less than 1.8 billion years oldParagraph 5: Along with the buildup of molecular oxygen (O2) came an eventual increase in ozone (O3) levels in the atmosphere. Because ozone filters out harmful ultraviolet radiation, this made it possible for life to flourish in shallow water and finally on land. This critical state in the evolution of the atmosphere was replaced (took place) between 1100 and 542 million years ago. Interestingly, the fossil record shows an explosion of life forms 542 million years ago.7. According to paragraph 5, which of the following happened sometime between 1100 and 542 million years ago?O A sudden explosion of life forms on land occurred together with a sharp decline of life in the water.O Ultraviolet radiation became more harmful to living organisms.O Molecular oxygen levels in the atmosphere stabilized, and ozone levels began to rise.O Ozone reduced ultraviolet radiation to a level acceptable for life on land.Paragraph 6: Oxygen has continued to play a key role in theevolution and form of life. Over the last 200 million years, the concentration of oxygen has risen from 10 percent to as much as 25 percent of the atmosphere, before setting (probably not permanently) at its current value of 21 percent. This increase has benefited mammals, which are voracious oxygen consumers. Not only do we require oxygen to fuel our high-energy, warm-blooded metabolism; our unique reproductive system demands even more. An expectant mother’s used (venous) blood must still have enough oxygen in it to diffuse through the placenta into her unborn child’s bloodstream. It would be very difficult for any mammal species to survive in an atmosphere of only 10 percent oxygen.8. According to paragraph 6, which of the following is NOT true of the connection between mammals and oxygen?O Mammals are able to survive only because oxygen levels are relatively high.O Mammals first emerged when atmospheric oxygen levels reached 10 percent.O A mammal’s unborn child receives oxygen through the mother’s placenta.O Mammals use a lot of oxygen partly because they are warm-blooded.Paragraph 7: Geologists cannot yet be certain why the atmospheric oxygen levels increased, but they have a hypothesis. First, photosynthesis is only one part of the oxygen cycle. The cycle is completed by decomposition, in which organic carbon combines with oxygen and forms carbon dioxide. But if organic matter is buried as sediment before it fully decomposes, its carbon is no longer available to react with the free oxygen. Thus there will be a net accumulation of carbon in sediments and ofoxygen in the atmosphere.Paragraph 5: Along with the buildup of molecular oxygen (O2) came an eventual increase in ozone (O3) levels in the atmosphere. ■Because ozone filters out harmful ultraviolet radi ation, this made it possible for life to flourish in shallow water and finally on land. ■This critical state in the evolution of the atmosphere was replaced between 1100 and 542 million years ago. ■Interestingly, the fossil record shows an explosion of life forms 542 million years ago.■9. Look at the four squares [■] that indicate where the following sentence could be added to the passage.The timing strongly suggests that atmospheric changes were responsible for this sudden increase in new life.Where w ould the sentence best fit? Click on a square [■] to add the sentence to the passage.10. Directions: An introductory sentence for a brief summary of the passage is provided below. Complete the summary by selecting the THREE answer choices that express the most important ideas in the passage. Some answer choices do not belong in the summary because they express ideas that are not presented in the passage or are minor ideas in the passage. This question is worth 2 points. Drag your choices to the spaces where they belong. To review the passage, click on View Text.Internal and external forces on Earth’s atmosphere have changed its chemical composition over time.Answer choicesO Mammals could not have survived without an oxygen-rich atmosphere, and land-based life would not be possible without the ozone layer to filter solar radiation.O Although they are currently at about 21 percent, oxygenlevels will probably not always remain this high.O The breakdown of organic matter removes free oxygen, but if this process is interrupted, extra oxygen may accumulate in the atmosphere.O Over the last 4 billion years, outgassing destroyed Earth’s primary atmosphere of volatile elements and replaced it with nonvolatile materials including carbon dioxide.O The sm all amount of oxygen in Earth’s early atmosphere was due to photodissociation and, later, photosynthesis created free oxygen.O When oxygen levels in the ocean water reached a critical level about 542 million years ago, life emerged in the oceans, as shown by sedimentary rocks.。

2023年高考英语外刊时文精读专题14气候变化与珊瑚礁(含答案)

2023年高考英语外刊时文精读专题14气候变化与珊瑚礁(含答案)

2023年高考英语外刊时文精读精练(14)Climate change and coral reefs气候变化与珊瑚礁主题语境:人与自然主题语境内容:自然生态【外刊原文】(斜体单词为超纲词汇,认识即可;下划线单词为课标词汇,需熟记。

)Human beings have been altering habitats—sometimes deliberately andsometimes accidentall y—at least since the end of the last Ice Age. Now, though, that change is happening on a grand scale. Global warming is a growing factor. Fortunately, the human wisdom that is destroying nature can also be brought to bear on trying to save it.Some interventions to save ecosystems are hard to imagine andsucceed. Consider a project to reintroducesomething similar to a mammoth(猛犸象)to Siberiaby gene-editing Asian elephants. Their feeding habits could restore the grassland habitat that was around before mammoths died out, increasing the sunlight reflected into space and helping keep carbon compounds(碳化合物)trapped in the soil. But other projects have a bigger chance of making an impact quickly. As we report, one example involves coral reefs.These are the rainforests of the ocean. They exist on vast scales: half a trillion corals line the Pacific from Indonesia to French Polynesia, roughly the same as the number of trees that fill the Amazon. They are equally important harbor of biodiversity. Rainforests cover18% of the land’s surface and offer a home to more than half its vertebrate(脊椎动物的)species. Reefs occupy0.1% of the oceans and host a quarter of marine(海洋的)species.And corals are useful to people, too. Without the protection which reefs afford from crashing waves, low-lying islands such as the Maldives would have flooded long ago, and a billion people would lose food or income. One team of economists has estimated that coral’s global ecosystem services are worth up to $10trn a year. reefs are, however, under threat from rising sea temperatures. Heat causesthe algae(海藻) with which corals co-exist, and on which they depend for food and colour, to generate toxins(毒素)that lead to those algae’s expulsion(排出). This is known as “bleaching(白化)”, and can cause a coral’s death. As temperatures continue to rise, research groups around the world are coming up with plansof action. Their ideas include identifying naturally heat-resistant(耐热的)corals and moving themaround the world; crossbreeding(杂交)such corals to create strains that are yet-more heat-resistant; employing genetic editing to add heat resistance artificially; transplantingheat-resistant symbiotic(共生的)algae; and even repairing with the bacteria and other micro-organismswith which corals co-exist—to see if that will help.The assisted evolution of corals does not meet with universal enthusiasm. Without carbon reduction and decline in coral-killing pollution, even resistant corals will not survive the century. Some doubt whetherhumans will get its act together in time to make much difference. Few of these techniques are ready for action in the wild. Some, such as gene editing, are so controversial that it is doubtful they will be approved any time soon. scale is also an issue.But there are grounds for optimism. Carbon targets are being set and ocean pollution is being dealt with. Countries that share responsibilities for reefs are starting to act together. Scientific methods can also be found. Natural currents can be used to facilitate mass breeding. Sites of the greatest ecological and economical importance can be identified to maximise benefits.This mix of natural activity and human intervention could serve as a blueprint (蓝图)for other ecosystems. Those who think that all habitats should be kept original may not approve. But when entire ecosystems are facing destruction, the cost of doing nothing is too great to bear. For coral reefs, at least, if any are to survive at all, it will be those that humans have re-engineered to handle the future.【课标词汇精讲】1.alter (通常指轻微地)改动,修改;改变,(使)变化We've had to alter some of our plans.我们不得不对一些计划作出改动。

高二英语海洋科学单选题40题

高二英语海洋科学单选题40题

高二英语海洋科学单选题40题1. There are many kinds of fish in the ocean. The ______ is one of them.A. sharkB. elephantC. tigerD. monkey答案:A。

本题考查海洋生物名词。

选项B“elephant”是大象,生活在陆地;选项C“tiger”是老虎,生活在陆地;选项D“monkey”是猴子,生活在陆地。

只有选项A“shark”鲨鱼是海洋生物。

2. The ______ can change its color to protect itself.A. dolphinB. starfishC. chameleonD. whale答案:B。

此题考查海洋生物特性。

选项A“dolphin”海豚不能变色;选项C“chameleon”变色龙,但它不是海洋生物;选项D“whale”鲸鱼也不能变色。

而选项B“starfish”海星可以改变颜色来保护自己。

3. Which of the following is NOT a marine mammal?A. SealB. JellyfishC. WalrusD. Orca答案:B。

本题考查海洋哺乳动物。

选项A“Seal”海豹、选项C“Walrus”海象、选项D“Orca”虎鲸都是海洋哺乳动物,而选项B“Jellyfish”水母是腔肠动物,不是哺乳动物。

4. The ______ has a hard shell and moves slowly.A. crabB. birdC. catD. rabbit答案:A。

本题围绕海洋生物的特征。

选项B“bird”鸟、选项C“cat”猫、选项D“rabbit”兔子都不是海洋生物,且没有硬壳。

而选项A“crab”螃蟹有硬壳且移动缓慢,是海洋生物。

5. Among these marine creatures, the ______ is known for its beautiful shape.A. sea urchinB. horseC. pigD. duck答案:A。

【必刷题】2024高一英语上册英语学术论文阅读专项专题训练(含答案)

【必刷题】2024高一英语上册英语学术论文阅读专项专题训练(含答案)

【必刷题】2024高一英语上册英语学术论文阅读专项专题训练(含答案)试题部分一、选择题:1. 在英语学术论文中,以下哪个部分通常用来概述研究背景和目的?A. IntroductionB. MethodologyC. ConclusionD. Literature Review2. 以下哪个词组常用于表示“结果表明”?A. As a resultB. It turns out thatC. The findings show thatD. In conclusion3. 在阅读英语学术论文时,以下哪个部分可以帮助我们了解研究方法?A. AbstractB. IntroductionC. MethodologyD. Discussion4. 以下哪个词组表示“在某种程度上”?A. To some extentB. In some wayC. On the other handD. As a matter of fact5. 在学术论文中,以下哪个标点符号用于引号内的句子结尾?A. CommaB. PeriodC. Question markD. Exclamation point6. 以下哪个词组表示“”?A. In additionB. HoweverC. ThereforeD. Moreover7. 在阅读学术论文时,以下哪个部分可以帮助我们了解研究的主要发现?A. IntroductionB. MethodologyC. ResultsD. Literature Review8. 以下哪个词组表示“尽管如此”?A. NeverthelessB. ThereforeC. MoreoverD. Otherwise9. 在学术论文中,以下哪个部分通常用于提出研究问题?A. IntroductionB. MethodologyC. DiscussionD. Conclusion10. 以下哪个词组表示“考虑到”?A. Taking into accountB. Given thatC. In order toD. On the condition that二、判断题:1. 学术论文的应简洁明了,直接反映研究主题。

挑战映日辉的英语作文

挑战映日辉的英语作文

The suns radiant brilliance is a common theme in English compositions,often used to symbolize hope,vitality,or the triumph of the human spirit.Here is a detailed English composition that captures the essence of the challenge against the suns dazzling light:Title:The Challenge of the Suns RadianceIn the vast expanse of the cosmos,the sun stands as a beacon of life,illuminating the Earth with its unyielding light.It is a symbol of warmth,energy,and the relentless cycle of day and night.Yet,the suns radiance is not just a passive force it is a challenge that humanity has faced and continues to confront in various forms.The suns challenge is multifaceted.It is a test of survival,as the scorching heat can be as destructive as it is lifegiving.It is a test of ingenuity,as we harness the suns energy to power our world.And it is a test of spirit,as we strive to understand the mysteries of the sun and our place in the universe.Survival Against the ElementsThe suns rays are a doubleedged sword.They provide the warmth necessary for life to flourish but can also bring about devastating heatwaves and droughts.In the deserts, where the suns challenge is most pronounced,life has adapted in remarkable ways.Plants and animals have developed unique strategies to conserve water and withstand the extreme heat.Humans,too,have learned to live with the suns harsh conditions,building homes that keep the heat out and finding ways to collect and store water. Harnessing Solar PowerThe suns energy is a gift that has been harnessed by humans for centuries.From the simple use of sunlight to dry clothes and food,to the sophisticated solar panels that convert sunlight into electricity,we have learned to tap into the suns radiance.The challenge here is to make this energy accessible and sustainable.Scientists and engineers are constantly innovating,developing more efficient solar cells and finding ways to store solar energy for use when the sun does not shine.Exploration and UnderstandingThe suns radiance is not just a physical phenomenon it is also a source of inspiration and curiosity.Astronomers and astrophysicists are drawn to the challenge of understandingthe suns complex processes.They study solar flares,sunspots,and the solar wind, seeking to unravel the mysteries of our star.This knowledge not only satisfies our innate curiosity but also has practical applications,such as predicting solar storms that can affect our technology and understanding the broader implications for the universe.The Human Spirit in the Face of the SunThe challenge of the suns radiance is also a metaphor for the human spirit.It represents the struggle against overwhelming odds,the pursuit of knowledge in the face of the unknown,and the resilience to adapt and thrive.Whether it is an athlete pushing through the heat of a marathon,a farmer working the land under the relentless sun,or a scientist delving into the mysteries of the cosmos,the suns challenge is a testament to our determination and perseverance.In conclusion,the suns radiance is a challenge that we cannot ignore.It is a call to action, a spur to innovation,and a reminder of our place in the grand scheme of things.As we continue to face the suns challenge,we grow stronger,wiser,and more connected to the world around us.The suns light may be blinding,but it is also illuminating,guiding us on our journey through life and the cosmos.。

新教材适用2024版高考英语二轮总复习第2部分阅读能力突破篇专题1阅读理解第9讲体裁破解__新闻报道

新教材适用2024版高考英语二轮总复习第2部分阅读能力突破篇专题1阅读理解第9讲体裁破解__新闻报道

第二部分专题一第9讲A(2023·辽宁省沈阳市高中高三二模)Swot satellite is scheduled to be launched Thursday morning to conduct a comprehensive survey of Earth's vital resource.By using advanced microwave radar technology it will collect height-surface measurements of oceans, lakes and rivers in high-definition detail over 90% of the globe.It's really the first time to observe nearly all water on the planet's surface.The major mission is to explore how oceans adjust climate change by absorbing atmospheric heat and carbon dioxide in a natural process.Oceans are estimated to have absorbed more than 90% of the extra heat trapped in the Earth's atmosphere by human-caused greenhouse gases.Swot will scan the seas and precisely measure fine differences in surface elevations(高度) around smaller currents and eddies(漩涡), where much of the oceans' decrease of heat and carbon is believed to occur.“Studying the mechanism will help climate scientists answer a key question: What is the turning point at which oceans start releasing, rather than absorbing, huge amounts of heat back into the atmosphere and speed up global warming, rather than limiting it,” said Nadya Shiffer, Swot's program scientist.By comparison, earlier studies of water bodies relied on data of rivers or oceans taken at specific points, or from satellites that can only track measurements along a one-dimensional line, requiring scientists to fill in data gaps through extrapolation(外推法).Thanks to the radar instrument, Swot can scan through cloud cover and darkness over wide ranges of the Earth.This enables scientists to accurately map their observations in two dimensions regardless of weather or time of day and to cover large geographic areas far more quickly than it was previously possible.“Rather than giving us a line of elevat ions, it's giving us a map of elevations, and that's just a total game changer,” said Tamlin Pavelsky, Swot freshwater science leader.1.What does the underlined expression “vital resource” in the first paragraph refer to?A.Technology.B.Climate.C.Oceans.D.Water.2.What is the major mission of Swot satellite?A.To identify when global warming is worsened.B.To explore where oceans absorb heat and CO2.C.To study how oceans influence climate change.D.To explain why greenhouse gas comes into being.3.What makes it possible for Swot to measure precisely?A.The high-definition computer.B.Advanced radar technology.C.The three-dimensional image.D.An accurate map of elevations.4.Which can be the best title for the text?A.A Solution to Climate ChangeB.A Breakthrough in Space TravelC.Successful Launch of Swot SatelliteD.First Global Water Survey from Space【语篇解读】本文是一篇新闻报道。

2023全国乙卷英语完型翻译

2023全国乙卷英语完型翻译

2023全国乙卷英语完型翻译2023 National College Entrance Examination (Gaokao) English Reading Comprehension Translation。

In recent years, the National College Entrance Examination (Gaokao) has undergone significant changes, and the English section is no exception. The 2023 Gaokao English paper aims to test students' reading comprehension skills through a variety of texts, including news articles, essays, and literary works. In this article, we will provide a translation of the reading comprehension section of the 2023 Gaokao English paper, offering students a better understanding of the questions and helping them prepare effectively.Text 1。

Most people are familiar with the concept of "fast fashion," which refers to the rapid production and consumption of inexpensive clothing. However, the environmental impact of fast fashion is often overlooked. The production of these garments leads to excessive water usage, pollution, and the generation of large amounts of waste. To address this issue, many fashion brands are now embracing sustainable practices and promoting ethical fashion.Question 1: What is the main concern raised in the text?A) The cost of fast fashion。

托福阅读tpo71R-1原文+译文+题目+答案+背景知识

托福阅读tpo71R-1原文+译文+题目+答案+背景知识

托福阅读tpo71R-1Electrical Energy from the Ocean原文 (1)译文 (5)题目 (8)答案 (15)背景知识 (16)原文Electrical Energy from the Ocean①Solar energy reaching Earth is responsible for differential heating of the atmosphere and thus air circulation as wind. Some of the energy of wind is transferred to the oceans, where it causes waves and is partly responsible for oceanic currents, although Earth’s rotation also plays a role in currents. Gravitational attraction between Earth and the Sun and Moon generates tides and, along with Earth’s rotation, causes most coastal areas to experience a twice-daily rise and fall of sea level. In short, the oceans possess a tremendous reservoir of largely untapped energy.②If we could effectively harness the energy possessed by the oceans, an almost limitless, largely nonpolluting energy supply would be ensured. Unfortunately, ocean energy is diffuse, meaning that the amount of energy for a given volume of water is small and thus difficult to concentrate and use. Several ways of using ocean energy are being considered or are under development, and one is currently in use, although it accounts for only a tiny proportion of all energy production. Of the several sources of ocean energy ---temperature differences with depth; currents; waves; and tides ---only the last shows much promise for the near future.③Ocean water at depth might be as much as 25℃colder than surface water, a difference that allows for ocean thermal energy conversion (OTEC). OTEC exploits this temperature difference to run turbines and generate electricity. The amount of energy available is enormous, but a number of practical problems must be solved before it can be used. For one thing, any potential site must be close to land and also have a sufficiently rapid change with depth to result in the required temperature difference. Furthermore, enormous quantities of warm and cold seawater would have to circulate through an electrical-generating plant, thus requiring that large surface areas bedevoted to this purpose.④The concept of OTEC is more than a century old, but despite several decades of research, no commercial OTEC plants are operating or even under construction, although small experimental ones have been tested in Hawaii and Japan.⑤Wind-generated ocean currents, such as the Gulf Stream, which flows along the east coast of North America, also posses energy that might be tapped to generate electricity. Unlike streams that can be dammed to impound a reservoir, any electrical-generating facility exploiting oceanic currents would have to concentrate currents’diffuse energy and contend with any unpredictable changes in direction. In addition, whereas hydroelectric generating plats on land depend on the rapid movement o water from the higher elevation to the turbines, the energy of ocean currents comes from their flow velocity, which is at most a few kilometers per hour.⑥The most obvious form of energy in the oceans lies in waves.Harnessing wave energy and converting it to electricity is not a new idea, and it has been used on an extremely limited scale. Unfortunately, the energy possessed by a wave is distributed along its crest and is difficult to concentrate. Furthermore, any facility would have to be designed to withstand the effects of storms and saltwater corrosion. The Japanese have developed wave-energy devices to power lighthouses and buoys, and a facility capable of providing power to about 300 homes began operating in Scotland during September 2000.⑦Perhaps tidal power is the most promising form of ocean energy. In fact, it has been used for centuries in some coastal areas to run mills, but its use at present for electrical generation is limited. Most coastal areas experience a twice-daily rise the fall of tides, but only a few areas are suitable for exploiting this energy source. One limitation is that the tidal range must be at least five meters, and there must also be a coastal region where water can be stored following high tide.⑧Suitable sites for using tidal power are limited not only by tidal range but also by location. Many areas along the U.S. Gulf Coast would certainly benefit from tidal power plants, but a tide range of generallyless than one meter precludes the possibility of development. Even areas with an appropriate tidal range such as the Arctic islands of Canada offer little potential because of their great distances from population centers.译文海洋电能①太阳能对地球的影响及海洋能量的潜力到达地球的太阳能是大气层差异加热的根源,进而导致空气循环,即我们所知的风。

2024年高一英语气候科学研究进展单选题40题

2024年高一英语气候科学研究进展单选题40题

2024年高一英语气候科学研究进展单选题40题1.Climate change is mainly caused by the increase in _____.A.greenhouse gasesB.ozone layerC.pollutantsD.water vapor答案:A。

温室气体的增加是气候变化的主要原因。

选项B 臭氧层主要起到阻挡紫外线的作用,与气候变化的主要原因关系不大。

选项 C 污染物的范围比较广,不是气候变化的主要原因。

选项 D 水汽也不是气候变化的主要原因。

2.The phenomenon of global warming is closely related to _____.A.carbon dioxide emissionsB.air pollutionC.water pollutionD.soil pollution答案:A。

全球变暖现象与二氧化碳排放密切相关。

选项B 空气污染不是全球变暖的直接主要原因。

选项C 水污染与全球变暖关系不大。

选项D 土壤污染也与全球变暖没有直接关系。

3.The term “El Niño” refers to _____.A.a weather patternB.a climate change phenomenonC.an ocean currentD.a type of storm答案:A。

“厄尔尼诺”是一种天气模式。

选项B 它不是气候变化现象本身。

选项C 它不是洋流。

选项D 它不是一种风暴。

4.The “greenhouse effect” is caused by _____.A.the absorption of heat by the atmosphereB.the reflection of sunlight by the EarthC.the emission of heat by the SunD.the cooling of the Earth答案:A。

2024届高考英语(新高考通用)压轴真题专项练习——阅读理解CD篇(医疗健康健身类)附答案

2024届高考英语(新高考通用)压轴真题专项练习——阅读理解CD篇(医疗健康健身类)附答案

2024届高考英语(新高考通用)压轴真题专项练习——阅读理解CD篇(医疗健康健身类)命题预测时代感。

从近年全国卷和各地高考试卷中科普类阅读命题的统计来看,高考阅读理解科普类文章的理论性和逻辑性强、生词多、句式结构复杂体现。

命题尊重语篇的文体特征和行文特点,考查了考生理解说明文语篇的能力,以及灵活运用各种阅读策略提取、归纳所读信息的能力,尤其加大了对概括能力和推断能力等高阶思维能力的考查。

预测1、说明文基本规律及解题要领高考中科普类阅读理解一般不给标题,反而经常要求考生选择最佳标题。

说明文一般采用如下四部分:首段:一般即是文章的主题段,开门见山点明新发明或研究对象。

背景: 交代问题的现状或研究的起因。

主干: 部分介绍研究所取得的突破,作者往往会详细介绍研究对象、研究方法、研究理论或具体的实验、统计等过程。

结尾: 通常会再次对中心进行概括、重述研究成果、预计的市场未来等与主题呼应。

二、说明文的解题技巧1. 运用语篇结构(text structure),了解文章大意科普说明文主题鲜明、脉络清晰,行文结构模式较为固定。

弄清文本结构有助于把握文章主旨和阅读重点。

医疗健身健康类文章多用描述法、问题与对策法等方法,通过列数据、做对比等来说明新的科学研究发现及其对医疗、疾病、健康等方面产生的影响。

结构上一般采用上述四个部分,说明手法上常使用以下说明方法:描述法(包括举例子、下定义、列数据等)、因果法、问题与对策法。

实验研究型文章一般会以实验的过程进展为线索,多用描述法、问题与对策法等方法,通过列数据、做对比等来说明新的科学研究发现及其产生的影响。

阅读时,首先用略读法快速浏览每段的首尾句,根据英语说明文思维模式特征,作者一般都会开门见山,直奔主题。

结尾通常也是中心思想的概括,并与导语相呼应。

因此在做主旨大意、写作意图和最佳标题等题目时,需要重点关注首尾段落里面高频复现的词汇和内容。

2. 定位标志词,分析长难句,进行逻辑推理判断每一个问题,在原文中,都要有一个定位。

Atmospheric carbon burial in modern lake basins and its

Atmospheric carbon burial in modern lake basins and its

Ž.Global and Planetary Change 302001167–195 r locate r gloplachaAtmospheric carbon burial in modern lake basins and itssignificance for the global carbon budgetGerhard Einsele a ,Jianping Yan a ,Matthias Hinderer b,)aGeological Institute,Sigwartstr.10,72076Tubingen,Germany ¨bGeologisch–Palaontologisches Institut,Schnittspahnstr.9,64287Darmstadt,Germany ¨Received 20July 2000;received in revised form 12September 2000;accepted 27April 2001AbstractŽke basins ;2.7=10km ,about 0.8%of the ocean surface or 2%of the land surface bury a surprisingly highŽ6.amount of atmospheric carbon ;70=10t r a which reaches more than one fourth of the annual atmospheric carbon burial in the modern oceans.This is mainly accomplished by the rapid accumulation of lacustrine sediments and a very high Ž.preservation factor on average 50times higher than that in the oceans .Lakes with relatively large drainage areas commonly display the highest carbon accumulation rates.In most cases,burial of organic matter is more important than that of carbonate carbon produced by silicate weathering,in contrast to the oceans where the burial of atmospheric carbonate carbon almost reaches the same amount as that of organic carbon.Exceptions to this rule are closed lake basins in arid to Ž.semiarid climate which precipitate a major part of their atmosphere-derived dissolved inorganic carbon DIC as carbonate.Ž.These results are demonstrated in some detail for L.Qinghai,China,low contribution of atmospheric carbonate carbon and Ž.L.Turkana,East Africa,high contribution from silicate rocks .Further data are gained by estimates for a number of closed and open lakes.The drainage areas of the lakes withdraw atmospheric carbon at rates of mostly 1–4g r m 2r a,calculated from the lacustrine carbon burial.Carbon burial rates in lakes commonly increase with change to wetter and warmer climate Žpartially larger lake surfaces,higher rates of seasonal carbonate precipitation,trend to stratified lake waters with .oxygen-deficient bottom water .Anthropogenic influence mostly enhances the production and preservation of organic carbon Ž.in lake basins often by a factor of 3–4.After the last glacial maximum,the joint action of the globally spreading vegetation,peat growth,and carbon burial in lakes would have been able to reduce the atmospheric carbon pool to one third to one half of its present amount within a time period of 1ka.However,CO exchange between the atmosphere and the 2ocean has brought about an overall increase in the atmospheric CO during the Holocene.The contribution of lakes and 2artificial reservoirs in counteracting man-made CO emissions should not be neglected.q 2001Elsevier Science B.V.All 2rights reserved.Keywords:modern lakes;atmospheric carbon burial;organic and carbonate carbon;global carbon budget;glacial–interglacial)Corresponding author.Tel.:q 49-6151-162671;fax:q 49-6151-166539.Ž.E-mail address:hinderer@geo.tu-darmstadt.de M.Hinderer .1.IntroductionThe global carbon budget,as well as temporal and regional variations in the carbon fluxes between the0921-8181r 01r $-see front matter q 2001Elsevier Science B.V.All rights reserved.Ž.PII:S 0921-81810100105-9()G.Einsele et al.r Global and Planetary Change302001167–195 168atmosphere and various compartments of the conti-nental and oceanic ecosystems,are still not suffi-ciently quantified.Whereas Pleistocene–Holocene changes in the carbon storage of the vegetation cover,peatlands,and soils on the continents haveŽrecently received considerable attention e.g.,several. articles in Faure et al.,1998;Adams and Post,1999, the importance of lakes as carbon sinks has been largely overlooked.Only a few authors have real-ized the importance of modern natural lake basins and artificial reservoirs as sinks of atmospheric Žcarbon Mulholland and Elwood,1982;Lerman.and Stumm,1989;Dean and Gorham,1998.ExceptŽ.in the work of Dean and Gorham1998,how-ever,carbonate carbon was not considered in these studies.The present-day chemical weathering rates on the continents are relatively well established from theŽsolute fluxes including organic and inorganic car-.Žbon of rivers all over the world e.g.,Ludwig et al., .1996.As to the bicarbonate fluxes of rivers,at-tempts have been made to discriminate between bi-carbonate associated with the weathering of eitherŽsilicate or carbonate rocks e.g.,Amiotte Suchez and.Probst,1995;Ludwig et al.,1998.It appears that about70%of the global riverine dissolved inorganic Ž.carbon flux DIC is of atmospheric origin,30%are derived from carbonates.Almost50%of the total DIC flux are ultimately buried as carbonate carbon in lakes and in the ocean.These relationships are essential for the net consumption of atmosphericCO because it is solely silicate weathering which 2withdraws carbon from the atmosphere by inorganic processes.On the other hand,it has been pointed out that increased chemical weathering of silicate rocks may be less relevant for the reduction of atmosphericCO and thus for a global cooling trend than the 2enhanced burial of organic matter in limited areas of the ocean,as in the Bengal fan of the Indian oceanŽduring the Neogene France-Lanord and Derry, .1997.Other authors have pointed out that periods of reduced deposition or increased dissolution of car-bonate in the ocean may have caused the glacial CO2Ždecrease of the atmosphere e.g.,Archer and Maier-.Reimer,1994.These and other problems of the global carbon cycle are discussed in Houghton et al.Ž.1996.Our approach in the study of lake basins differs in some aspects from previous studies.We consider denudation–accumulation systems of limited extent consisting of the drainage and lake areas of selected closed and open lake basins.In some of these sys-tems,the processes of chemical weathering control-ling both the river fluxes to the lake basins and theŽburial of specific species in the lake sediments in-.cluding organic and inorganic carbon can be quanti-fied.For many other lake basins,total sediment accumulation rates,carbonate contents,and organic carbon contents are available which allow estimates of their carbon burial rates.The fraction of atmo-spheric carbon in the deposited carbonate carbon is found by evaluating the rock types in the drainage areas.Although we have considered only a small number out of the enormous number of modern lake basins,we believe that our results contribute to the closing of a significant gap in the general knowledge of the global carbon budget and its temporal varia-tion.Publications on lakes and lake sediments are widely distributed in many journals covering limno-logical,sedimentological,biological,and environ-mental aspects.Only a limited number of these papers could be rmation on the sources,nature,microbial metabolism and remineral-ization,resuspension,and diagenesis of lacustrine organic matter is summarized in some books andŽreview articles e.g.,Wetzel,1975;Meyers and Ishi-.watari,1993and not discussed here.Inventories on the size,volume,and drainage areas of the world’sŽ. large lakes have been provided by Herdendorf1988Ž.and Meybeck1995.In the following,we introduce our general con-cept and report the most important results from the study of two middle-sized lake basins,L.Qinghai in western China and L.Turkana in East Africa.The results from other,large and small,closed and open lake basins of different climatic zones are mainly listed in tables supplemented by some remarks.Fi-nally,the significance of our results is documented by comparing them with published data on the global cycling and budget of carbon.()G.Einsele et al.r Global and Planetary Change302001167–1951692.Carbon budget of lake basins:concept and definitions2.1.Influxes from the drainage areaŽ.The total riverine carbon flux TC to a lake basin from its drainage area comprises three components Ž.Fig.1:Ž.Ž.1dissolved organic carbon DOC,Ž.Ž.2particulate organic carbon POC,Ž.Ž.3dissolved inorganic carbon DIC.These components are commonly noted as con-Ž.Žcentrations mg r l in river water,loads g r a or t r a;.Ž2a s year,or as specific yields e.g.,SDIC,g r m r a2.or t r km r a,related to the drainage area.Although DOC can reach significant concentrations in rivers originating from poorly drained soils and swamps Ž.e.g.,Meybeck,1982;Ludwig et al.,1996,its con-tribution to organic carbon burial in lakes is very limited and therefore neglected here.However,ter-restrial POC often contributes substantially to the carbon burial in both lacustrine and marine sedi-ments,particularly so in or close to tropical and subtropical regions.POC can also be transported by wind,which carries considerable amounts of terres-trial plant debris into the sea and into some large lake basins of arid regions.DIC is a major compo-nent of all river waters and therefore of particular interest here.2.2.Storage and burial of carbonA very small fraction of the riverine TC is storedŽ.in the lake waters cf.Fig.5.DOC is almost completely used up in the lake by biogenic activity and mineralization.The terrestrial POC is also largely decomposed and mineralized,but some of it can beŽburied as allochthonous organic matter OM,ex-.pressed here as organic carbon OC with the lake sediments.The primary organic production in the lake,controlled by the ecology and nutrient supply of the lake,is partially buried as autochthonousŽ. organic carbon see, e.g.,Wetzel,1975.In the following,no distinction is made between al-lochthonous and autochthonous organic carbon,sum-marized as OC,present in the lake sediments.Similar to POC and DOC,only a small fraction ofŽ. the DIC input is stored in lake waters cf.Fig.5.In closed lake basins,about one half of the incoming DIC can be deposited as biogenic and chemicallyŽ. precipitated total carbonate carbon TCC in combi-nation with the riverine dissolved Ca and Mg.Open Fig.1.Definitions for the carbon budget of lake basins.()G.Einsele et al.r Global and Planetary Change302001167–195 170lake systems commonly precipitate much less of theriverine bicarbonates.The sedimentary OC and TCC are expressed in g r a,g r ka,etc.,for the total lake orŽ2as mass accumulation rates MARs;g r m r a s 2.t r km r a.2.3.Carbon loss from the lake basinOrganic and inorganic carbon which is not buried with the lake sediments can leave the lake by de-gassing of CO,in dissolved form with the outflow2Ž.from open lake systems,and by subsurface leak-age.The solubility of CO is very low in lake waters2of high alkalinity,but the concentration of HCO—3 may be high and thus also the loss of DIC by leakage.Some of the DIC is also taken up by clay minerals which undergo reverse weathering within the lake.For these reasons,the total loss of carbon-ate species from a lake basin is difficult to assess.In the case of closed lakes,the discrepancy betweenŽ. influx and storage in lake water and sediment approximately indicates the carbon loss out of the Ž. lake basin mainly into the atmosphere;cf.Fig.5.2.4.Burial r influx ratioThe relationship between organic carbon pre-served in lacustrine or marine sediments and produc-tion of organic carbon,"including the influx ofPOC,is often expressed by the preservation factor Ž.e.g.,Einsele,1992,2000;see also below.This termcannot be used for the burial of carbonate carbonwhich plays a significant role in this study.Wetherefore propose a somewhat different approach.The burial r influx ratio,BIR,describes the rela-tionship between the organic carbon and au-Ž. tochthonous total carbonate carbon OC q TCC de-posited in the lake and DIC q DOC q POC derived from the drainage area.OC includes part of the catchment-derived POC;TCC should not contain detrital carbonate.The burial r influx ratio is definedŽ.in terms of masses per time unit g r a or t r a for theŽtotal lake or as mass accumulation rates MAR;22.g r m r a or t r km r a and specific yields of thedrainage area,e.g.,SDIC,per unit area and time:OC q TCCBIR sDIC q DOC q POCMAR q MAROC TCCor1Ž.SDIC q SDOC q SPOC The burial r influx ratio characterizes the efficiency of the denudation–accumulation system to deposit and preserve both organic and inorganic carbon.In those cases where DOC and POC fluxes to theŽ. basin are very low and can be neglected,Eq.1is simplified to:OC q TCC MAR q MAROC TCCBIR s or1aŽ.DIC SDICIf BIR and DIC are known or can be assumed withŽ.some confidence,Eq.1a can be used to determine the role of a lake in the burial of atmospheric carbon. In this case,however,the drainage area must be devoid of carbonates and carbonate-bearing rocks.Then the burial of total atmospheric carbon,TC,AT can be estimated without the knowledge of the masses or accumulation rates of the lake sediments:w xTC s DIC=BIR t r a2Ž.ATor2STC s SDIC=BIR=A r A t r km r a2aŽ.AT L Dwhere A s drainage area and A s lake area.TheD Lspecific withdrawal rate of carbon from the atmo-sphere,STCAT,is related to A,analog to theDspecific yield,SDIC,of DIC.For carbonates and mixed rock types in the drainage area,this simple relationship has to be Ž.modified Section2.6.In general,BIR values of lakes drained from silicate rock regions are consider-ably greater than those of lakes surrounded by car-bonates and carbonate-bearing rocks,where atmo-spheric carbon is buried almost exclusively as OC.2.5.DIC fluxes to ancient closed-lake basinsThe riverine DIC fluxes to ancient closed lakes can be estimated if the amount of authigenic lake carbonate,e.g.biogenic and biochemically precipi-tated CaCO can be determined for a certain time 3period.Many closed lakes are supersaturated withŽ.respect to Ca Mg CO.Thus,neglecting loss by3leakage,all the inflowing Ca q Mg is trapped in the lake basin.Carbonates are precipitated by groundwa-ters as cement in alluvial deposits and directly in the lake as marl or limestone.Considering the mass of()G.Einsele et al.r Global and Planetary Change302001167–195171CaCO present in all the sediments and the atomic 3and molecular weights of carbon and CaCO,the3 mass of total carbonate carbon,TCC,buried in the lake is:TCC s0.12CaCO3Ž.3If MgCO or Na CO is present,e.g.in dolomite or 323soda,a similar calculation can be made.To transport Ca and Mg as bicarbonates,at least twice as much carbon is necessary than found in the lake carbonate. The ancient DIC flux therefore amounted to at least:DIC s0.24CaCO4Ž.3Assuming that the inflow composition remained con-stant through time,one can also calculate the masses of total dissolved matter,TDS,if the fractions of DIC or Ca in TDS are known,e.g.from present-dayŽing burial r inflow ratios BIR,Eq.Ž..1found for modern lakes,an attempt can be made to determine carbon burial rates for ancient lake ŽŽ..systems Eq.2.This concept is not tested further here.()2.6.Carbon sources atmosphere and rocks and their partitioningThe proportion of DIC originating from the atmo-sphere depends on the composition of the soils and rocks exposed to weathering in the drainage area in question.In regions of carbonate rocks,about half of the riverine DIC is derived from the atmosphere.The remainder comes from the dissolved carbonate min-erals in the drainage area.In regions of silicate rocks or sediments containing relatively unstable silicate minerals,but being devoid of carbonate,the riverine DIC reflects silicate weathering and is entirely atmo-spheric.The dissolved bicarbonates entering the lake,Ž.e.g.as Ca HCO,bind about twice as much of the32riverine DIC than needed for carbonate precipitationŽŽ..in the lake as autochthonous CC Eq.4.The other half of DIC is used by organisms or leaves the lake,Ž.mostly by outgassing CO see above.It is only the2Žweathering of silicates and the riverine fluxes of.DOC and POC which draw CO from the atmo-2sphere by inorganic processes.In addition,someCO from the atmosphere may directly enter the lake 2surface due to continuous or seasonal high primaryŽorganic production tropical lakes and middle to.high-latitude lakes,resp..Thus,organic carbon,OC Ž.including some POC,buried with the lake sedi-ments and that part of the total autochthonous lacus-trine carbonate carbon,TCC,derived from theweathering of silicate rocks,,originateATfrom the atmosphere.The amount of total carbon,Ž.TC e.g.,in t r ka,withdrawn from the atmo-ATsphere and buried in a lake is:TC s OC q CC5Ž.AT ATFor drainage areas solely consisting of silicate rocks, this means:TC s OC q TCC6Ž.ATFor pure carbonates,it is:TC s OC6aŽ.ATFor mixed rock types and carbonate-bearing rocks,it is:TC s OC q a fraction of TCC7Ž.ATŽ.Eq.7is further discussed below.Expressing TC as specific withdrawal,STCAT AT Ž2.e.g.,in t r km r a,from the atmosphere per unitŽ.land area similar to specific yield and using mass accumulation rates for the lake sediments,one gets: for silicate rocks:STC s MAR q MAR=A r A8Ž.Ž.AT OC TCC L Dfor pure carbonates:STC s MAR=A r A9Ž.AT OC L DŽwhere A s lake area;A s drainage area.In Eqs.L DŽ.Ž.8and9,the units of mass and area have to be the22. same for all parameters,e.g.g r m r a s t r km r a.As mentioned above,allochthonous detrital car-bonate coming from the drainage area has to be subtracted from the total carbonate deposited in the lake.Its proportion of the total lake carbonate is mostly small,as in the examples discussed below.Many drainage areas of lake basins,particularly those of large lakes,are characterized by a mixture of various soil and rock types.The ratios of specific inorganic carbon yields,SDIC,from different rock()G.Einsele et al.r Global and Planetary Change302001167–195 172types at similar runoff conditions are as follows Ž.Amiotte et al.,1993,1995:Plutonic and metamorphic rocks1Acid volcanic rocks 3.5 Basaltic rocks shales7 Carbonate rocks17This means that the SDIC of carbonate rocks is17 times greater than that of plutonic rocks,but only half of the DIC delivered by carbonate rocks comes from the atmosphere.SDIC from basalts is twice that of acid volcanics,but in these cases,all DIC are atmospheric.Unfortunately,the evaluation of DIC yields from mixed rock types is even more complex.Carbonate-Ž.bearing soils and rocks e.g.,marls have almost theŽ.same specific DIC yield SDIC as pure carbonates if the climate conditions are similar.For the same rock type,SDIC increases with enhanced specific runoff. Rocks protected by a thick clayey cover produced low SDICs regardless of the nature of the underlying rocks.Quartzose sandstones have lower SDICs thanŽ. granites and gneisses see,e.g.Einsele,2000.For all these reasons and other factors controlling the rates of weathering,a precise partitioning of the carbon derived from the atmosphere and various rocks is difficult.In context of this paper,a simpli-fied method is used.It is based on the following observations:Ž.–The mean carbonate yield ratio,CYR cf.Fig.2,Ž.of the specific DIC yields SDIC of carbonate-bearing rocks and silicate rocks of a certain climatic region,as determined in river water,mostly ranges from4:1to6:1.At a global scale,Berner et al.Ž.1983have found a ratio range of4:1.–For groundwater,emanating in springs,this ratio is 4–6:1.Ž.Assuming a DIC yield ratio of5:1CYR s5,theatmospheric fraction,g CC,of the buried totalATcarbonate carbon,TCC,in closed lakes is:a g SIL ag CC s s s RTFAT a g SIL q b g CBT a q5b10Ž. where a s fraction of drainage area covered by car-bonate-free silicate rocks,SIL;b s fraction ofŽ. drainage area covered by carbonate rocksCBT Fig.2.Rock type factor,RTF,as a function of silicate rocks,SIL,ŽŽ..in the drainage area Eq.10and the DIC yield ratio,CYR,of carbonate-bearing and silicate rocks.Ž.a qb s1,g SIL s1,relative specific DIC yield of silicate rocks,g CBT s5,relative DIC yield of car-bonate rocks,DIC yield ratio,CYR sg BT r g SILŽs5.RTF is the so-called rock type factor see .below.Ž.Using Eq.10,the atmosphere-derived carbon stored in the lake carbonate is:a g SILCC s TCC s RTF=TCC AT a g SIL q b g CBT11Ž. and the total atmospheric carbon stored in the lake asŽŽ..CC and OC is compare Eq.7:ATTC s OC q RTF=TCC12Ž.ATŽ.or,using mass accumulation rates MARs:w x TC s MAR q RTF=MAR A t r a Ž.AT OC TCC L13Ž.To determine the total specific carbon withdrawalrate from atmosphere,STC,mass accumulationATrates for the lake sediments and the ratio of the lakeŽŽ. area r drainage area have to be applied cf.Eqs.8Ž..and9:STC s MAR q RTF=MAR A r AŽ.AT OC TCC L D=2t r km r a14Ž.()G.Einsele et al.r Global and Planetary Change302001167–195173Ž.Ž.Ž.Notably,Eqs.8,9and13demonstrate that the burial of atmospheric carbon is controlled by theŽmass accumulation rates or linear sedimentation .rates of OC and CC in the lake.In the followingATŽŽ.Ž.Ž.Ž. examples,particularly Eqs.8,9,12,13and Ž.14are used.2.7.Error eÕaluationThe results to be gained by the methods outlined above may be subject to considerable error.Refer-Ž.ring to Eq.13,the following parameters are most important:Ž.–The mass accumulation rates MARs available from central parts of a lake may not be representa-tive for the entire lake area,apart from delta sedi-ments,which are excluded from this study.This uncertainty may cause an error by a factor2.How-ever,one has to bear in mind that increased accumu-lation rates of detrital material lead to lower percent-Ž.ages by weight of OC and autochthonous CC by dilution but not necessarily to lower accumulation rates of these constituents.–In the published data on OC contents of young surface sediments,it is not always clear whether the organic matter undergoes further benthic degradation which would reduce the OC content of the deeper sediment.Due to rapid sediment accumulation and decrease of bacterial activity with depth in lacustrine sediments,this uncertainty is probably of minor im-portance.This is supported by high-resolution stud-ies of cores which have sampled the sediment–water interface and have found only little carbon lossŽ. within the sediment Talbot and Laerdal,2000.–The fractions of silicate and carbonate rocks,a and b,in a drainage area,needed to determine the rock type factor,RTF,are often not well known.Carbon-ate-bearing rocks and sediments,including Quater-nary deposits and periglacial cover layers may be-have in a similar way as pure carbonate rocks and thus reduce the fraction of silicate rocks.–The ratio of specific DIC yields,CYR,coming from carbonate and silicate rocks,may deviate fromŽ.that used above5:1.The impact of the last two factors is shown in Fig.2.If,for example,the fraction of silicate rocks in the drainage area is-0.5and the SDIC yield ratio high Ž.e.g.,CYR s8,the factor RTF becomes very small Ž.-0.11.This means that a certain amount of lake carbonates does not contribute very much to the burial of atmospheric carbon.A high contribution of the same amount of lake carbonate is only realized when the fraction of silicate rocks exceeds about0.7 and the SDIC yield ratio,CYR,drops to5or less.Further problems are mentioned in the brief dis-cussions about individual lake basins.3.Atmospheric carbon burial in modern closed lakes3.1.Two test basins:L.Qinghai and L.TurkanaWe first present two examples of closed-lake basins which have been worked out in a study on the chemical evolution of their lake waters and saltŽ.mineral precipitation Yan,1998.Lake Qinghai is located in the northeastern part of the Qinghai-Xizang Plateau,China,it occupies an intermontane rift depression presumably formed in the Pliocene and lies in a region of semi-arid conti-nental climate at an altitude of3194m a.s.l.Its drainage area is dominated by sedimentary rocks Ž. limestones,shales and sandstones and a minor Ž.Žproportion ca.20%of silicate rocks Fig.3;LZIG, .1979.The lake became topographically closed about Ž.15ka BP Yuan et al.,1990and now covers an area 2Žof4340km mean water depth16m,salinity14.1 .g r l,pH9.2.The following mass balance is basedŽ.on the past10ka Lister et al.,1991.Lake Turkana is the largest water body in the eastern branch of the East African Rift system.Since about4000years,it has been topographically closed Ž.time span of following mass balance,and its water level fluctuated between20and50m above theŽpresent level Cerling,1986;Yuretich,1986;Barton .Žet al.,1987.The modern lake is shallow mean.Žwater depth31m and of moderate salinity 2.5g r l, .pH9.3.Its drainage area is characterized by Pre-cambrian granitic and metamorphic rocks and widespread late Tertiary–Quaternary volcanic ter-Ž.rains Fig.4.Both lakes are oligotrophic and there-fore bury limited amounts of organic matter.Further data from both lakes are listed in Table1.They()G.Einsele et al.r Global and Planetary Change 302001167–195174Fig.3.Location of Lake Qinghai and the lithologies in its drainage area.P and P ,mean annual precipitation in drainage area and over the d l lake.include the concentrations of those species of the river inflow which are relevant here as well as various characteristics of the lake sediments.For reasons of simplicity,it is here assumed that DOC and POC influxes from the drainage area and leak-age of brine out of the lake basins can be neglected and that,in addition,the composition of the river inflow remained constant during the time period considered.The results of our calculations are summarised in Table 1and Fig. 5.For Lake Qinghai,the bulk Ž.masses of the Holocene 10ka lake sediments,their organic carbon and authigenic carbonates were esti-mated using data for different facies zones and sedi-Ž.ment thicknesses within the basin Yan,1998.Then the mean mass accumulation rates,MARs,were determined for the entire lake.The present-day total biomass in the lake water reaches 1,75=1011g organic carbon,OC,which corresponds to about Ž65%of the annual DIC influx Fig.5;to convert organic matter to carbon,a factor of 0.546was used;.Yan,1998.Inorganic carbon,DIC,dissolved in the lake water is about 60times more than the annual DIC influx.About 87%of the DIC influx are re-Žturned via the lake surface to the atmosphere includ-.ing loss by leakage .The annual DIC flux into L.Turkana is higher than that into the Qinghai lake due to the larger drainage area.The present lake water stores 600=1011g DIC,which is about equal to the DIC influx of 86years.DIC released as CO into the atmo-2sphere amounts to 57%of the DIC influx.The differences between the two lakes can be seen best by comparing the total mass accumulation Ž.rates of atmospheric carbon,MAR Table 1.This TC Ž2.value is much greater in L.Turkana 25g r m r a()G.Einsele et al.r Global and Planetary Change302001167–195175Fig.4.Location of Lake Turkana and the lithologies in its drainage area.P and P,mean annual precipitation in drainage area and over thed llake.。

英语阅读图片及参考答案

英语阅读图片及参考答案

英语阅读图片及参考答案在英语教学中,图片是一种非常有效的辅助工具,它可以帮助学生更好地理解和记忆文本内容。

以下是一篇英语阅读材料,以及相应的图片和参考答案,旨在提高学生的阅读理解能力和分析能力。

阅读材料:The Amazon Rainforest, often referred to as the "lungs of the Earth," is a vast tropical rainforest that stretches across the northern South America. It is the largest rainforest in the world and is home to an incredible diversity of plant and animal species. The Amazon covers an area of about 6.7million square kilometers, which is roughly the size of the 48 contiguous United States.The Amazon is a treasure trove of biodiversity. It is estimated that it contains over 400 billion individual trees, representing more than 16,000 species. The rainforest is also home to about 2.5 million species of insects, 2,200 species of birds, and 4,000 species of mammals. Many of these species are found nowhere else on the planet.The Amazon plays a critical role in the global climate. It absorbs large amounts of carbon dioxide and releases oxygen into the atmosphere through the process of photosynthesis. However, the rainforest is under threat due to deforestation and climate change, which are causing the loss of habitat formany species and contributing to global warming.图片:1. A panoramic view of the lush Amazon Rainforest with dense vegetation.2. A close-up of a variety of trees and plants, showcasing the diversity of species.3. A group of vibrantly colored birds perched on branches.4. An aerial view showing the extent of deforestation, with patches of cleared land.问题:1. What is the Amazon Rainforest known as, and why?2. How large is the Amazon Rainforest, and what does it cover in terms of area?3. What is the estimated number of individual trees in the Amazon, and how many species do they represent?4. What role does the Amazon play in the global climate, and what are the threats it faces?参考答案:1. The Amazon Rainforest is known as the "lungs of the Earth" because of its significant role in absorbing carbon dioxide and releasing oxygen into the atmosphere.2. The Amazon Rainforest is the largest rainforest in the world, covering an area of about 6.7 million square kilometers, which is approximately the size of the 48contiguous United States.3. The Amazon is estimated to contain over 400 billion individual trees, representing more than 16,000 species.4. The Amazon plays a critical role in the global climate by absorbing carbon dioxide and releasing oxygen. The threats it faces include deforestation and climate change, which lead to habitat loss for many species and contribute to global warming.通过这篇阅读材料和图片,学生不仅能够了解亚马逊雨林的基本情况,还能够认识到保护雨林的重要性。

2020年职称英语考试理工类AB级阅读判断练习(3)

2020年职称英语考试理工类AB级阅读判断练习(3)

2020年职称英语考试理工类AB级阅读判断练习(3)The Northern LightsThe sun is stormy and has it own kind of weather.It is so hot and active that even the Sun's gravity cannot hold its atmosphere in check! Energy flows away from the Sun towardthe Earth in a stream of electrified particles that move at speeds around a million miles per hour.These particles are called plasma,and the stream of plasma coming from the Sun is called the solar wind.The more active the Sun,the strongerthe solar wind.The solar wind constantly streams toward the Earth,butdon't worry because a protective magnetic fields surroundsour planet.The same magnetic field that makes your compasspoint north also steers the particles from the Sun to thenorth and south poles.The charged particles become trapped in magnetic belts around the Earth.When a large blast of solar wind crashes into the Earth’s magnetic field first gets squeezed and then the magnetic field lines break and reconnect.The breaking and reconnecting of the magnetic field lines can cause atomic particles called electrons trapped in thebelts to fall into the Earth's atmosphere at the poles.As the electrons fall into the Earth,they collide with gas moleculesin the atmosphere,creating flashes of light in the sky.Each atmospheric gas glows a different color.Oxygen and nitrogen glows red and green and nitrogen glows violet-purple.As these various colors glow and dance in the night sky,they createthe Northern Lights and the Southern Lights.Watching auroras is fun and exciting,but normally you can only see them in places far north like Alaska and Canada.The movement of the aurora across the sky is usually slow enough to easily follow with your eyes but they can alsopulsate,flicker,or even move like waves.During solar maximum,auroras are seen as far south as Florida,even Mexico!Auroras often seem to be very close to the ground,but the lowest aurora is still about 100 kilometers above the ground,a distance much higher than clouds are formed or airplanes can fly.A typical aurora band can be thousands of kilometers long,a few hundred kilometers high,but only a few hundred meters thick.We hope you are able to travel to far-north places like the Arctic Circle and see the Northern Lights at least once during your lifetime.We know you will never forget it!1.The Sun's gravity is too weak to keep its plasma from flowing to the Earth.A.rightB.wrongC.not mentioned2.The Earth is quite safe with a magnetic field surrounding it to protect it from the attack by the solar wind.A.rightB.wrongC.not mentioned3.Some scientists are worrying about the possible disappearance of the Earth's protective magnetic field in the future.A.rightB.wrongC.not mentioned4.The auroras are formed when the electrons falling into the Earth's atmosphere at the poles and colliding with gas molecules in the atmosphere.A.rightB.wrongC.not mentioned5.You cannot see the Northern Lights unless you are in Alaska or Canada.A.rightB.wrongC.not mentioned6.Tens of thousands of tourists take special trips to Norway and Sweden every year to watch the Northern Lights.A.rightB.wrongC.not mentioned7.An aurora is generally close to the ground and is very long and thick.A.rightB.wrongC.not mentioned。

高考英语一轮复习必修2Module6FilmsandTVProgrammes课时规范训练(含解析)

高考英语一轮复习必修2Module6FilmsandTVProgrammes课时规范训练(含解析)

Module 6 Films and TV Programmes[基础巩固篇]一、默写版块Ⅰ.重点单词请快速写出下列单词对应的汉语意思1.thriller n. 充满刺激的电影2.sword n. 剑3.fiancé n. 未婚夫4.telly n. (非正式)电视5.drama n. 戏剧6.shark n. 鲨鱼7.masterpiece n. 杰作8.ad n. 广告9.rooftop n. 屋顶10.section n. 部分;节11.graceful adj. 优美的;优雅的请快速写出下列英语单词12. poster n.海报13. character n.角色;人物14. leap v.跳跃;飞跃15. plot n.情节16. channel n.频道请快速写出下列英语单词及拓展单词17. actress n.女演员actor n.男演员act v.表演18. female adj.女的;女性的male adj.男的;男性的19. interest vt.使感兴趣interested adj.感兴趣的interesting adj.令人感兴趣的20. brave adj.勇敢的bravery n.勇敢21. moving adj.感人的moved adj.感动的move vt.使感动22. argue vi.争论argument n.争论23. entertaining adj.有趣的;令人愉快的entertain vt.使愉快entertainment n.愉快24. occasionally adv.有时;偶尔occasional adj.有时的;偶尔的occasion n.场合;时机25. setting n.(小说、戏剧、电影的)背景set vt.以……为背景Ⅱ.高频短语1. e out 出现;出版;发行2. fall in love with 爱上;喜欢(表动作)3. be in love with 爱上;喜欢(表状态)4. to one's surprise 令某人吃惊的是5. in surprise 吃惊地6. tell of 讲述7. care about 关心;顾虑;在乎8. every now and then 有时;偶尔9. a number of 若干,许多10. play a part 扮演角色11. at the age of 在……岁时Ⅲ.经典句型1. Brave,good and strong ,Xiulian is the character we care about most.我们最关注秀莲这个角色,她勇敢、善良、坚强。

高考英语时文阅读与强化练习:新一代养生潮流,Z世代簇拥茶文化

高考英语时文阅读与强化练习:新一代养生潮流,Z世代簇拥茶文化

Young people increasingly find that traditionis their cup of tea新一代养生潮流,Z世代簇拥茶文化英文新闻:Young people increasingly find that tradition is their cup of tea In a burst of springtime flavor, new-style Chinese tea chain, Molly Tea, has attracted beverage enthusiasts with its latest creation, Yongchun Foshou. Made from the renowned oolong tea of the same name from Yongchun County, Quanzhou, Fujian Province, this new offering has quickly become a hit. Yet, it is merely a highlight in a series of new brands that have taken the tea market by storm.Young consumers are really getting into new Chinese-style (xinzhongshi) tea drinks and desserts. Even though young people have been enjoying milk tea and fruit tea, their interest in traditional Chinese tea keeps growing.A recent report from the China Tea Marketing Association stated that as young people aged 18 to 30 gradually became the main drinkers of the beverage, such trends as guochao ("National tide" or "China chic"), wherein younger consumers prefer products made innovatively with Chinese elements, such as with aspects of intangible cultural heritage, are gainingtraction. Modern Chinese teahouses have emerged as a fresh socializing spot for the youth, signaling an upgrade of the drink's consumption.Wang Qing, president of the China Tea Marketing Association, says that as consumers favor more high-quality drinks, traditional premium teas are becoming the top choice, which is also boosting the consumption and innovation.重点词汇1. chic英 [ʃiːk]美 [ʃiːk]n. 特种风格,时髦雅致2. traction英[ˈtrækʃn]美[ˈtrækʃn]n. 牵引力中文新闻:新一代养生潮流,Z世代簇拥茶文化在这个春意盎然的季节里,新式中国茶叶连锁店茉莉奶白的最新产品永春佛手吸引了众多饮品爱好者。

2024年高一英语气候科学研究进展练习题40题

2024年高一英语气候科学研究进展练习题40题

2024年高一英语气候科学研究进展练习题40题1.Climate change is mainly caused by the increase in _____.A.greenhouse gasesB.pollutionC.wasteD.noise答案:A。

“greenhouse gases”是温室气体,气候变化主要是由温室气体增加引起的。

“pollution”污染,范围太广,不一定直接导致气候变化。

“waste”废物,和气候变化关系不大。

“noise”噪音,与气候变化毫无关系。

2.Scientists are studying ways to reduce _____.A.climate changeB.global warmingC.pollution levelsD.carbon emissions答案:D。

“carbon emissions”是碳排放,科学家正在研究减少碳排放的方法。

“climate change”气候变化是结果不是要减少的对象。

“global warming”全球变暖也是结果。

“pollution levels”污染水平,比较宽泛,不如减少碳排放具体针对气候变化。

3.The melting of glaciers is a result of _____.A.rising temperaturesB.polluted airC.waste disposalD.noise pollution答案:A。

冰川融化是温度上升的结果。

“polluted air”污染的空气,不是冰川融化的直接原因。

“waste disposal”废物处理,与冰川融化无关。

“noise pollution”噪音污染,和冰川融化毫无关系。

4.One way to combat climate change is to increase the use of _____.A.fossil fuelsB.renewable energyC.nuclear powerD.coal答案:B。

惠州2024年10版小学六年级上册D卷英语第4单元综合卷

惠州2024年10版小学六年级上册D卷英语第4单元综合卷

惠州2024年10版小学六年级上册英语第4单元综合卷考试时间:90分钟(总分:120)A卷考试人:_________题号一二三四五总分得分一、综合题(共计100题)1、填空题:The chicken lays _______ (蛋) in the coop.2、填空题:Understanding how to attract beneficial ______ can help your garden thrive.(了解如何吸引有益生物可以帮助你的花园茁壮成长。

)3、听力题:The _______ of a flashlight beam widens as it moves away from the source.4、听力题:The temperature at which a gas condenses into a liquid is its ______ point.5、How many planets are in our solar system?A. 7B. 8C. 9D. 106、What is the color of a typical goldfish?A. SilverB. BlueC. OrangeD. Yellow答案:C7、填空题:The __________ is a large reservoir in the United States. (胡佛水坝)8、填空题:The country famous for its spices is ________ (印度).9、What is the name of the sweet dessert that is typically served on birthdays?A. CakeB. PieC. TartD. Pudding答案: A10、听力题:The process of breaking down food in our bodies releases _____.11、听力题:The chemical formula for sodium carbonate is __________.12、How many colors are in a rainbow?A. 5B. 6C. 7D. 8答案:C13、填空题:A ________ (冰川) can create valleys as it moves.14、填空题:My favorite sport is ______ (拳击).15、What do you call the hot liquid inside a volcano?A. MagmaB. LavaC. AshD. Gas答案:A16、填空题:A _____ (63) is a place where animals live in the wild.17、听力题:A _______ is a tool used to measure temperature changes.18、听力题:We attend ________ (school) every day.19、填空题:I saw a _____ (magnolia) tree in bloom.What is the main ingredient in soup?A. WaterB. VegetablesC. MeatD. All of the above21、填空题:The ________ (历史遗迹) tell stories of the past.22、填空题:The __________ (历史的追求) enriches lives.23、What is the capital of France?A. BerlinB. MadridC. RomeD. Paris答案: D24、选择题:What is the name of the insect that makes silk?A. AntB. ButterflyC. SilkwormD. Bee25、填空题:The ancient Romans are known for their ________ and contributions to law.26、听力题:A ______ is a type of reaction that produces a gas.27、听力题:Chemical reactions can be exothermic or _____ (endothermic).28、填空题:The ______ (种植) of native plants supports local wildlife.29、What is the name of the fairy tale character with long hair?A. RapunzelB. CinderellaC. Snow WhiteD. Aurora答案:AMy favorite _____ is a bright blue kite.31、填空题:The first person to win the Nobel Prize in Physics was _______. (亨利·贝克勒尔)32、What do you call a person who sells flowers?A. FloristB. GardenerC. HorticulturistD. Botanist33、听力题:The process of making hydrogen gas from electrolysis involves _______.34、How many strings does a standard guitar have?A. 4B. 5C. 6D. 7答案: C35、填空题:A _______ (小乌龟) hides in its shell when scared.36、Which vegetable is orange and long?A. PotatoB. CarrotC. TomatoD. Cucumber答案:B37、听力题:The Earth's surface is shaped by a combination of internal and ______ forces.38、听力题:The chemical formula for calcium phosphate is ______.39、What is the term for the study of the Earth's physical features?A. BiologyB. GeologyC. GeographyD. Meteorology答案:BA ____(circular economy model) minimizes waste through reuse.41、填空题:The tree has many ______.42、填空题:The dolphin swims with its _________. (伙伴)43、听力题:The ______ is known for her innovative projects.44、听力题:A barn owl hunts at ______.45、What do we use to write?A. BrushB. PencilC. HammerD. Spoon答案: B46、听力题:We will go to the ______ for a field trip. (museum)47、听力题:A molecule of carbon dioxide consists of one carbon and _______ oxygen atoms.48、听力题:We are going to _____ ice cream later. (eat)49、填空题:A parakeet loves to sing and ______ (说话).50、听力题:The ______ is known for its bright colors.51、填空题:A parakeet can be blue or ______ (绿色).52、填空题:Many _____ (insect) live on the leaves.53、What do we call a young female horse?A. FillyB. ColtC. FoalD. Mare54、听力题:The __________ is where most life forms exist.55、What do we call a young cow?A. CalfB. KidC. LambD. Foal56、填空题:We celebrate our ______ (生日) with cake.57、填空题:The starling can mimic other _______ (声音).58、听力题:The chemical formula for sodium bicarbonate is ______.59、Which part of the body do we use to hear?A. EyesB. EarsC. NoseD. Mouth答案:B60、听力题:The _____ (铁路) connects cities.61、填空题:I like to ______ (玩) in the park after school.62、填空题:A ________ (岛) is surrounded by water.63、填空题:The __________ (历史的景象) reflects society.64、填空题:The turtle carries its _______ (壳) everywhere.65、听力题:I like to _______ (collect) stickers.66、Which planet is known as the Red Planet?A. EarthB. MarsC. JupiterD. Saturn67、填空题:I like to swim in the ______.68、填空题:She is a scientist, ______ (她是一名科学家), studying the environment.69、填空题:The _______ (The Space Race) was a competition for supremacy in space exploration.70、听力题:A mineral's streak is the color of its ______ powder.71、听力题:Bees help ______ plants by pollinating.72、填空题:I admire __________ (科学家) for their discoveries.73、听力题:An endothermic reaction absorbs ______.74、填空题:The __________ was a significant event in the fight for civil rights in America.(黑人民权运动)75、选择题:What is the largest ocean?A. AtlanticB. IndianC. ArcticD. Pacific76、填空题:The rabbit's fur helps keep it ______ (温暖).77、What is the name of the famous bridge in San Francisco?A. Brooklyn BridgeB. Golden Gate BridgeC. London BridgeD. Sydney Harbour Bridge答案: B. Golden Gate Bridge78、How many zeros are in one thousand?A. TwoB. ThreeC. FourD. Five答案: B79、Which bird is known for its colorful feathers?A. SparrowB. ParrotC. PigeonD. Penguin答案: B80、听力题:Some flowers bloom at _______ times of the year.81、选择题:What is the main ingredient in a salad?A. BreadB. LettuceC. CheeseD. Meat82、填空题:I love to _____ (explore) the woods for plants.83、What do we call the act of inspiring others to take action?A. MotivationB. EmpowermentC. EncouragementD. All of the Above答案:D84、听力题:The substance that is dissolved in a solution is called the _______.85、填空题:My uncle is very .86、填空题:Flowers bloom in _____ (春天) and bring color to the garden.87、听力题:I enjoy _____ with my friends. (playing)88、听力题:Plants absorb carbon dioxide through their ______.89、填空题:The _______ (Wright brothers) are credited with inventing the first airplane.90、填空题:The goose honks loudly in the _______ (湖).91、填空题:Many ________ (动物) depend on plants for food.92、What is the name of the famous painting by Leonardo da Vinci?A. The Starry NightB. The Last SupperC. Mona LisaD. Girl with a Pearl Earring答案:C93、填空题:A _______ (金鱼) can be orange, yellow, or white.94、填空题:The __________ (花园) is filled with colorful blooms.95、听力题:The chemical formula for ethanol is ______.96、听力题:The chemical formula for chromium oxide is _______.97、听力题:My cousin is a ______. She enjoys hiking.98、填空题:The _____ (植物生长潜力) can be studied in various habitats.99、What is the name of the famous English author known for his detective stories?A. Agatha ChristieB. Arthur Conan DoyleC. Charles DickensD. J.K. Rowling答案:B100、填空题:I often invite my friends over for a toy ________ (名词) party. We share our favorites and play together.。

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Key words. Stars: fundamental parameters – Stars: abundances – Galaxy: disk – Galaxy: formation – Galaxy: abundances – Galaxy: kinematics and dynamics
Abundances expressed within brackets are as usual relative to solar values: [O/Fe] = log(NO /NFe )⋆ − log(NO /NFe )⊙ 2 These brackets indicate that the spectral line is forbidden and should not be confused with the notation of abundances given relative to solar values.
T. Bensby, S. Feltzing, and I. Lundstr¨ om
Lund Observatory, Box 43, SE-221 00 Lund, Sweden
arXiv:astro-ph/0310741v1 27 Oct 2003
Received 21 July 2003/ Accepted 24 October 2003
abundance of oxygen ([O/Fe]1 > 0) indicates that the region have had a high star formation rate and undergone a fast chemical enrichment (e.g. Tinsley 1979; Matteucci & Greggio 1986). The determination of oxygen abundances is unfortunately often troublesome due to the limited number of available oxygen lines in the visual part of a stellar spectrum. The main indicators are the O triplet at ∼ 7774 Å, the forbidden [O ]2 lines, especially those at 6300 Å and 6363 Å, the ultraviolet (UV), and the infrared (IR) OH lines. The analysis of these lines all have their difficulties. The triplet at 7774 Å should be ideal to work with since its lines are strong and are located in a clean part of the spectrum that is free from blending lines. The lines are, however, strongly affected by deviations from local thermal equilibrium (LTE) (see e.g. Kiselman 1991) and, even if these deviations are considered not very well understood even for the Sun, they are probably due to convective inhomogeneities (Kiselman 1993). The forbidden lines are very robust indicators but are hard to work with since
1. Introduction
Oxygen is, next to hydrogen and helium, the most abundant element in the Universe. Of the three stable isotopes 16 O, 17 O, and 18 O, the first is the dominating one, making up ∼ 99.8 % of the total oxygen content in the Solar system. Oxygen is a bona fide primary element that essentially only forms in the interiors of massive stars through hydrostatic burning of mainly He, C, and Ne. By analyzing elemental abundances in the atmospheres of long-lived F and G dwarf stars it is not only possible to determine the chemical composition of the gas that the stars were born out of but also to trace the chemical history in the different stellar populations in the Milky Way. In this respect the oxygen fossil record is of extra importance and is often used in models of Galactic evolution. It can, among other things, be used to measure the rates of supernovae type II (SN II) and supernovae type Ia (SN Ia) with time (e.g. Wheeler at al. 1989). An overSend offprint requests to: Thomas Bensby, thomas@astro.lu.se ⋆ Based on observations collected at the European Southern Observatory, La Silla and Paranal, Chile, Proposals #65.L-0019, 67.B0108, and 69.B-0277 ⋆⋆ The full Table 4 is only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cats/J.A+A.all.htx
Abstract. We present oxygen abundances for 72 F and G dwarf stars in the solar neighbourhood. Using the kinematics of
the stars we divide them into two sub-samples with space velocities that are typical for the thick and thin disks, respectively. The metallicities of the stars range from [Fe/H] ≈ −0.9 to +0.4 and we use the derived oxygen abundances of the stars to: (1) perform a differential study of the oxygen trends in the thin and the thick disk; (2) to follow the trend of oxygen in the thin disk to the highest metallicities. We analyze the forbidden oxygen lines at 6300 Å and 6363 Å as well as the (NLTE afflicted) triplet lines around 7774 Å. For the forbidden line at 6300 Å we have spectra of very high S /N (>400) and resolution (R 215 000). This has enabled a very accurate modeling of the oxygen line and the blending Ni lines. The high internal accuracy in our determination of the oxygen abundances from this line is reflected in the very tight trends we find for oxygen relative to iron. From these abundances we are able to draw the following major conclusions: (i) That the [O/Fe] trend at super-solar [Fe/H] continues downward which is in concordance with models of Galactic chemical evolution. This is not seen in previous studies as it has not been possible to take the blending Ni lines in the forbidden oxygen line at 6300 Å properly into account; (ii) That the oxygen trends in the thin and the thick disks are distinctly different. This confirms and extends previous studies of the other α-elements; (iii) That oxygen does not follow Mg at super-solar metallicities; (iv) We also provide an empirical NLTE correction for the infrared O triplet that could be used for dwarf star spectra with a S /N such that only the triplet lines can be analyzed well, e.g. stars at large distances; (v) Finally, we find that Gratton et al. (1999) overestimate the NLTE corrections for the permitted oxygen triplet lines at ∼ 7774 Å for the parameter space that our stars span.
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