墨尔本PTE素材库——Greenland’s Meltwater May Fertilize Fjords with Phosphorus

墨尔本PTE素材库——Greenland’s Meltwater May Fertilize Fjords with Phosphorus

中文批注

冰川融化除了带来上涨的海平面，还会带来什么？这篇报道告诉我们，格陵兰岛上融化的冰川同时还会将丰富的矿物质如磷等带入海洋中，随着冰川的融化，格陵兰岛的冰川河流带入海洋中的磷，竟然等同于密西西比河和亚马逊河带入海洋中磷的总量！是不是很惊人呢？

澳大利亚语言学院会定期整理一些PTE的素材库，旨在用这些与Question Criteria高度契合的素材，让大家在平日复习的时候有题可练，有素材可学习。光靠PTE官方所给出的那些复习材料，想要大幅度的提升自身英语水平，其实是远远不够的。

这段材料，虽然不长，但是有一些日常不会接触到的生词，如phytoplankton，oxygenated等等。难度和题材都非常适用于练习Re-tell Lecture，或者当成一篇阅读材料。如果你听完了，试试你能不能讲解清楚，Greenland’s Meltwater 会对海洋造成怎样的作用吧！关键信息，就在整个Podcast的后半段哦~

【key Vocabulary】

Phosphorus: 磷

Estimate: 估计，估价

Meltwater: 冰雪融化成的水

Dumping: 倾销，倾泻

Nutrient: 营养物，滋养物

Mineral: 矿物，矿物的

Arctic: 北极的

Grind: 磨碎

Glacial: 冰的，冰冷的

Biogeochemist: 生物地球化学工作者

Reactive:  反应的

Trace: 追踪，追溯

Lattice: 晶格，格子，格架

Funnel: 漏斗，烟囱

Flush: 发红，奔涌，用水冲洗

Par: 标准，平均数量

Fertilizer: 肥料

Phytoplankton: [植] 浮游植物

Speculate: 推测，投机，思索

Runoff: 径流，流走的东西。

Ultimately: 最后，根本，基本上

Oxygenated: 氧化的，充满氧气的

Organism: 有机体，生物体，微生物

Full Transcript

Greenland’s glacial rivers may flush some 400,000 tons of phosphorus into ocean waters—on par with the Mississippi or the Amazon. Christopher Intagliata reports.

The massive ice sheet topping Greenland is losing nearly 300 billion tons a year to melting, according to NASA estimates. And all that meltwater means rising seas. But it’s also dumping huge amounts of nutrients and minerals into Arctic waters.

“The great thing about glaciers and ice sheets, is that they’re these big, very heavy systems, and as they move over rock they grind and crush the rock up.” Jon Hawkings, a glacial biogeochemist at the University of Bristol in the U.K. “So they expose all these reactive kind of trace components of the rock lattice to the fresh meltwater that’s coming in.”

That meltwater funnels rock dust into Greenland’s glacial rivers, where Hawkings and his colleagues took their samples. They found that Greenland’s rivers are much richer in phosphorus than previously believed. And they estimate that Greenland’s glacial rivers may flush some 400,000 tons of phosphorus into ocean waters every year—that’s on par with the amount of phosphorous dumped into the ocean by the Mississippi or Amazon rivers. The findings appear in the journal Global Biogeochemical Cycles. [Jon Hawkings et al, The Greenland Ice Sheet as a hot spot of phosphorus weathering and export in the Arctic]

All that extra phosphorus could be fertilizer for ocean life. “It’s an essential nutrient for phytoplankton, who are the guys on the bottom of the food chain. So it’s really, really important for life. And life can’t exist without it.” And this process—glaciers grinding rocks, then melting and flushing those nutrients to sea—it’s not the first time it’s happened. In fact, the authors speculate that during the last extreme ice age—the so-called “snowball Earth,” some 700 million years ago—all this phosphorus runoff may have caused a bloom in ocean life. A bloom that may have ultimately oxygenated the planet…and paved the way for organisms like us.

—Christopher Intagliata

(Source: http://www.scientificamerican.com/podcast/episode/greenland-s-meltwater-may-fertilize-fjords-with-phosphorus/)