TOEFL TPO -1 Writing Task 1 Sample: Sure. There are some concerns about iron fertilization. I'm going to address the concerns and explain why I think iron fertilization is a very good idea. First, it's true that iron fertilized phytoplankton in the experiments did not absorb a lot of carbon dioxide. However, these studies are unconvincing, because they were too short. Most of them lasted less than a month. But it turns out that phytoplankton plants live for 2 or 3 months and absorb most carbon dioxide in the last month of their lives. So phytoplankton may not be efficient absorbers of co two during the first month. But the efficiency would probably greatly increase in the second and third month.
Second, it's true that phytoplankton may occasionally produce too many environmental toxins in certain areas. But this problem can be easily addressed if we just stop fertilizing those areas with iron. If we stop fertilizing the areas, the phytoplankton will not have enough nutrition and will quickly start dying out. As a result, the production of the toxins will quickly decline, and there will be no permanent damage.
Finally, it's true that we don't really know the long term effects of iron fertilization on ocean ecosystems. But this is a risk we may have to take. Because if we don't, we will be facing a much greater risk. The rapid changes to earth's climate will probably cause much greater harm to the ocean ecosystems than iron fertilization ever could. We have to act now in a big way to reduce carbon dioxide. If we want to slow climate change, and iron fertilization is one of our best bets it's exceeding. • LingoLeap