ST_007
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综合写作
Some scientists have proposed an interesting way to slow down global climate change: they want to increase the growth of phytoplankton in Earth’s oceans by fertilizing the oceans with iron dust. Phytoplankton are tiny, ocean-dwelling plants that can absorb great amounts of carbon dioxide (CO2). Since carbon dioxide contributes enormously to global warming, increasing phytoplankton by iron fertilization is expected to slow global warming. However, there are many potential problems with iron fertilization.
First, iron fertilization may not be very effective. So far, only very few experiments have shown that iron fertilization leads to increased absorption of atmospheric CO2 by phytoplankton. In addition, the increases in CO2 absorption detected in the experiments were quite small. This leads many experts to think that full-scale iron fertilization would be just as ineffective.
Second, the quick growth of phytoplankton can lead to dangerous increases in environmental toxins. Some phytoplankton produce toxins that are relatively harmless in small amounts but can be very dangerous when produced by a large enough population. The toxins kill some species of fish, which hurts the fishing industry. They also cause other species of fish to be poisonous for human consumption, which causes many people to become sick. If we implement iron fertilization, we can expect this to happen much more often.
Third, seeding the oceans with large volumes of a nutrient such as iron could upset the oceans’ ecological balance. We do not know how the various ocean organisms will react to an iron-rich environment. Some may thrive in it, while others may suffer. In the long run, iron fertilization could change the plant and animal composition of the ocean ecosystems; some species may even become extinct as a result.
学术写作：
教授：为了保护环境，政府应该做点什么来鼓励人们用电车？
Claire：多建电桩。
Paul：给电动车修专用道。
Doctor Achebe: As countries work to reduce emissions and protect the environment, many governments are encouraging the adoption of electric vehicles through new policies. This week we will discuss ideas for policies that could promote electric vehicle usage. In your post, I would like you to address this question: What policies should the government implement to promote electric vehicles for environmental protection?
Claire: More charging stations are key to getting people to buy electric cars. It’s frustrating when you can’t charge your car. The government should offer big tax credits to businesses to build charging stations. If charging spots are everywhere, range anxiety will go away and electric car sales will take off. We need that to help the Earth.
Paul: The government needs to create entire highways just for electric cars. These special roads could have charging stations along the way so range anxiety disappears. Exclusive electric highways would show electric cars are the transportation of the future. We’d see tons more Teslas on the road helping clear the air.
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