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The True "Bottom" of the Food Chain Is Plenty Polluted 食物链最底层——遭污染的深海食物

The Mariana Trench¹ is the deepest spot in the world’s oceans. Only three humans have ventured into the trench in submersibles. But plenty of our pollution has made the voyage to the bottom of the sea: a new study finds that critters living more than six miles below the ocean surface contain high levels of harmful compounds like polychlorinated biphenyls, or PCBs, and flame retardants.

马里亚纳海沟是全球海洋最深的地方。只有3个人曾乘潜水器冒险进入这一壕沟。然而，人类制造的许多污染物已经潜入了海底:一项新的研究发现，生活在海平面六英里以下的生物体内含有高浓度的有害化合物——比如多氯联苯（PCBs）和阻燃剂。

“An important thing is that, if you’re in the deepest place in world, there’s no place to go.”

“重点是，当你身处世上最深之地时，你就再无其他可去之处了。”

Alan Jamieson, a marine² ecologist at Newcastle University in the U.K.

英国纽卡斯尔大学的海洋生态学家艾伦·杰米森（Alan Jamieson）说道。

\“You can’t be disturbed horizontally. You can’t go back up. So, for every nanogram of pollutant³ that’s gone into the deep sea, there’s no mechanism⁴ to put it back again. So, of course the values are going to be high, cause it’s only a one way traffic, right?”

“无法水平移动，也无法回到上层海域。所以，对于每一纳克进入深海的污染物，都没有途径再把它拉回去。因而，付出的代价势必会很高，毕竟这是一条单行道，不是吗？”

Jamieson and his colleagues used robotic traps to collect deep-sea amphipods living in the most remote parts of the oceans. These creatures look a bit like shrimp⁵, and they’re well adapted to their extreme environment, he says.

杰米森和同事们利用机器人捕捞来收集生活在海洋最偏远地区的深海片脚类动物。他说，这些生物看起来有点像虾，而且它们很能适应极端的环境。

“The deep sea-ones are incredible scavengers. This is why they thrive in the deep sea, because it’s a low-food environment where most of their food comes from dead carcasses raining from the surface or particulates⁶ coming down. So, everything from an organic particle to a dead whale is fair game to an amphipod.”

“这些深海动物是能力惊人的食腐动物。这就是为什么它们能在深海中茁壮成长。因为这是一个食物匮乏之地，它们的大部分食物来自雨水从地表冲下来的死去的动物尸体或落下来的微粒。所以，对片脚类动物来说，从一颗有机粒子到一只死鲸，一切物质都是可捕食的猎物。”

The food that floats down to the ocean bottom carries man-made contaminants, including PCBs, which entered the surface ocean from rivers and coastlines. Companies stopped manufacturing these chemicals in the 1970s, after they were found to be dangerous. But they don’t break down easily, so they’re still swirling⁷ around in the oceans and working their way down to the seafloor, where amphipods gobble them up.

漂向海底的食物含有人造污染物，包括从河流和海岸线流进海面的多氯联苯。上世纪70年代，人们发现这些化学物质很危险，此后公司便停止了生产。但它们很难分解，所以它们仍然在海洋中盘旋，并一路飘向海底，在那里被片脚类动物吞噬。

The research was published in the journal Nature Ecology and Evolution.

这项研究发表在《自然生态与进化》杂志上。

In many surface-dwelling species, PCBs have been shown to interfere⁸ with animals’ abilities to reproduce. Jamieson says they don’t have enough data yet to know how deep-sea amphipods are faring, because they’re much harder to study. But he says that wasn’t his motivation for studying pollutants⁹ in the deep ocean.

在许多水面生的物种中，多氯联苯已被证明会损害它们的繁殖能力。杰米森表示，他们还没有足够的数据来了解深海片脚类动物的生活方式，因为它们研究起来比较困难。但他说，这并不是他研究深海污染物的动机。

“The point is that they are there. It’s to challenge people’s perception that the deep sea is not exempt¹⁰ from what’s happening in the rest of the world. And that’s a perception we hear quite a lot of.”

“重点是它们到了那里。这对人们的看法是一种挑战，即深海并不能免受世界其他地区的影响。而现实中我们经常听说那种看法。”