英语科普：海洋酸化对浮游植物有巨大影响

Oceans have absorbed up to 30 percent of human-made carbon dioxide around the world, storing dissolved carbon for hundreds of years. As the uptake of carbon dioxide has increased in the last century, so has the acidity1 of oceans worldwide. Since pre-industrial times, the pH of the oceans has dropped from an average of 8.2 to 8.1 today. Projections2 of climate change estimate that by the year 2100, this number will drop further, to around 7.8 - significantly lower than any levels seen in open ocean marine3 communities today. Now a team of researchers from MIT, the University of Alabama, and elsewhere has found that such increased ocean acidification will dramatically affect global populations of phytoplankton - microorganisms on the ocean surface that make up the base of the marine food chain. In a study published today in the journal Nature Climate Change, the researchers report that increased ocean acidification by 2100 will spur a range of responses in phytoplankton: Some species will die out, while others will flourish, changing the balance of plankton4 species around the world. The researchers also compared phytoplanktons response not only to ocean acidification, but also to other projected drivers of climate change, such as warming temperatures and lower nutrient5 supplies. For instance, the team used a numerical model to see how phytoplankton as a whole will migrate significantly, with most populations shifting toward the poles as the planet warms. Based on global simulations, however, they found the most dramatic effects stemmed from ocean acidification. Stephanie Dutkiewicz, a principal research scientist in MITs Center for Global Change Science, says that while scientists have suspected ocean acidification might affect marine populations, the groups results suggest a much larger upheaval6 of phytoplankton - and therefore probably the species that feed on them - than previously7 estimated. Ive always been a total believer in climate change, and I try not to be an alarmist, because its not good for anyone, says Dutkiewicz, who is the papers lead author. But I was actually quite shocked by the results. The fact that there are so many different possible changes, that different phytoplankton respond differently, means there might be some quite traumatic changes in the communities over the course of the 21st century. A whole rearrangement of the communities means something to both the food web further up, but also for things like cycling of carbon.词汇解析1 acidity n.酸度，酸性参考例句：This plant prefers alkaline soil,though it will readily tolerate some acidity.这种植物在酸性土壤中也能生存，但硷性土壤更加适宜。Gastric acidity would not prevent the organism from passing into the gut.胃的酸度不能防止细菌进入肠道。2 projections 预测( projection的名词复数 )； 投影； 投掷； 突起物参考例句：Their sales projections are a total thumbsuck. 他们的销售量预测纯属估计。The council has revised its projections of funding requirements upwards. 地方议会调高了对资金需求的预测。3 marine adj.海的；海生的；航海的；海事的；n.水兵参考例句：Marine creatures are those which live in the sea. 海洋生物是生存在海里的生物。When the war broke out,he volunteered for the Marine Corps.战争爆发时，他自愿参加了海军陆战队。4 plankton n.浮游生物参考例句：Plankton is at the bottom of the marine food chain.浮游生物处于海洋食物链的最底层。The plankton in the sea feeds many kinds of animals. 海的浮游生物成为很多种动物的食物。5 nutrient adj.营养的，滋养的；n.营养物，营养品参考例句：Magnesium is the nutrient element in plant growth.镁是植物生长的营养要素。The roots transmit moisture and nutrient to the trunk and branches.根将水分和养料输送到干和枝。6 upheaval n.胀起，(地壳)的隆起；剧变，动乱参考例句：It was faced with the greatest social upheaval since World War .它面临第二次世界大战以来最大的社会动乱。The country has been thrown into an upheaval.这个国家已经陷入动乱之中。7 previously adv.以前，先前（地）参考例句：The b