[2008.12.30]Troubled Waters海洋问题堪忧

A special report on the sea

Troubled waters海洋问题堪忧

Dec 30th 2008
From The Economist print edition

The sea is suffering, mostly at the hand of man, says John Grimond
约翰•格里蒙德：海洋状态堪忧，罪魁祸首就是人类。

All of us have in our veins the exact same percentage of salt in our blood that exists in the ocean…And when we go back to the sea…we are going back from whence we came.
John Kennedy
盐在海里的比例和它在人类血管中流淌的血液的完全一样……所以，当我们回归大海，我们也回归故乡。

HUMAN beings no longer thrive under the water from which their ancestors emerged, but their relationship with the sea remains close. Over half the world’s people live within 100 kilometres (62 miles) of the coast; a tenth are within 10km. On land at least, the sea delights the senses and excites the imagination. The sight and smell of the sea inspire courage and adventure, fear and romance. Though the waves may be rippling or mountainous, the waters angry or calm, the ocean itself is eternal. Its moods pass. Its tides keep to a rhythm. It is unchanging.
人类自海而来，尽管现在，海底已不是我们生存发展之地，但人类和海洋的密切关系却不曾改变。居住地离海岸不到100公里（62英里）的人口高达一半以上，10公里以内的也占到十分之一。至少在陆地上人们会认为，海洋既是情感之根，又是想象之源。观其貌，闻其味，顿时倍增勇气，起程壮游，却又平添惊恐，演绎传奇。海浪既可没没汩汩，又能浩浩汤汤，既可白浪滔天，又能水波不兴，但海洋本身却亘古不变：忘我、循序、如一。

Or so it has long seemed. Appearances deceive, though. Large parts of the sea may indeed remain unchanged, but in others, especially in the surface and coastal waters where 90% of marine life is to be found, the impact of man’s activities is increasingly plain. This should hardly be a surprise. Man has changed the landscape and the atmosphere. It would be odd if the seas, which he has for centuries used for food, for transport, for dumping rubbish and, more recently, for recreation, had not also been affected.
或者说，至少人们一直是这么想的，但这却是个假象。确实，大一部分是始终如一的，但还有一部分，尤其是海面和近海水域，人类活动的影响却日益显著，因为90%的海洋生物都聚集在此。这种现象也是不足为奇的。人类已经改变了地貌和大气，如果说海洋还没有受到影响那就太奇怪了，何况几百年来海洋都是食品仓库、运输方式、垃圾处理场，近来又成为休闲娱乐场所。

The evidence abounds. The fish that once seemed an inexhaustible source of food are now almost everywhere in decline: 90% of large predatory fish (the big ones such as tuna, swordfish and sharks) have gone, according to some scientists. In estuaries and coastal waters, 85% of the large whales have disappeared, and nearly 60% of the small ones. Many of the smaller fish are also in decline. Indeed, most familiar sea creatures, from albatrosses to walruses, from seals to oysters, have suffered huge losses.
证据不胜枚举。人们原先认为，鱼类是我们取之不尽的食物，但现在，几乎全世界的鱼类资源都成下降趋势：科学家认为，大型肉食性鱼类锐减90%（大型的包括金枪鱼、旗鱼、鲨鱼等），河口和近海水域的大型鲸鱼减少了85%，小型的也少了近60%。许多小鱼的命运也同样多舛。确实，信天翁、海象、海豹、牡蛎……这些最常见的海洋生物数量锐减，难更仆数。

All this has happened fairly recently. Cod have been caught off Nova Scotia for centuries, but their systematic slaughter began only after 1852; in terms of their biomass (the aggregate mass of the species), they are now 96% depleted. The killing of turtles in the Caribbean (99% down) started in the 1700s. The hunting of sharks in the Gulf of Mexico (45-99%, depending on the variety) got going only in the 1950s.
而这种情况是最近几个世纪才开始的。新斯科舍捕了几个世纪的鳕，但大量捕捞却是1852年以后才开始的；从生物量（单位面积的种群质量）的角度来看，其缩减额达到96%；加勒比海18世纪才开始捕杀海龟（下降99%）；到了20世纪50年代墨西哥湾才开始捕杀鲨鱼（根据种类不同，下降45%到99%）。

The habitats of many of these creatures have also been affected by man’s activities. Cod live in the bottom layer of the ocean. Trawlermen in pursuit of these and other groundfish like pollock and haddock drag steel weights and rollers as well as nets behind their boats, devastating huge areas of the sea floor as they go. In the Gulf of Mexico, trawlers ply back and forth year in year out, hauling vast nets that scarify the seabed and allow no time for plant and animal life to recover. Off New England, off west Africa, in the Sea of Okhotsk north of Japan, off Sri Lanka, wherever fish can still be found, it is much the same story.
人类活动也对这些生物的栖息地发生影响。鳕栖于海洋底层。拖捞船为了捕捉鳕和其他如鳕鱼或黑线鳕之类的底栖鱼，拖着钢铁水力挖掘机，背后还拉着深海拖网，一路走去，大面积的海床就被破坏怠尽了。墨西哥湾的拖捞船年复一年地来来往往，拉着巨大的拖网，破坏了海床，甚至不给海洋动植物恢复的机会。新英格兰、非洲西海岸、日本鄂霍次克海、斯里兰卡……可以说，只要还能找到鱼，情况都是大同小异的。

Coral reefs, whose profusion of life and diversity of ecosystems make them the rainforests of the sea, have suffered most of all. Once home to prolific concentrations of big fish, they have attracted human hunters prepared to use any means, even dynamite, to kill their prey. Perhaps only 5% of coral reefs can now be considered pristine, a quarter have been lost and all are vulnerable to global warming.
珊瑚礁是海洋中生物最丰富、生态系统最多样的地方，因而被喻为“海洋热带雨林”，但它却是破坏最严重的地区。过去，大鱼往往栖居于此，因此，它就吸引了大批渔民，为了捕获猎物，人类可以不择手段，包括炸弹。现在未遭受人类破坏的珊瑚礁大约只剩5% ，被完全破坏的占到1/4，但所有的珊瑚礁在全球气候变暖上都是不堪一击的。

A hotter atmosphere has several effects on the sea. First, it means higher average temperatures for surface waters. One consequence for coral reefs is that the symbiosis between the corals and algae that constitute a living reef is breaking down. As temperatures rise, the algae leave or are expelled, the corals take on a bleached, white appearance and may then die.
气候变暖对海洋有以下几点影响。首先，海面平均气温上升，对珊瑚礁的一个影响是，构成珊瑚礁的珊瑚虫和海藻逐渐分解，随着温度的上升，海藻要么不再参与构成，要么就被珊瑚虫所驱逐，珊瑚礁被“漂白”，色彩日趋苍白，最后，可能会死亡。

Hotter water, slimier slime更热的水，更粘的泥

Warming also has consequences for ice: it melts. Melting sea ice affects ecosystems and currents. It does not affect sea levels, because floating ice is already displacing water of a weight equal to its own. But melting glaciers and ice sheets on land are bringing quantities of fresh water into the sea, whose level has been rising at an average of nearly 2 millimetres a year for over 40 years, and the pace is getting faster. Recent studies suggest that the sea level may well rise by a total of 80 centimetres this century, though the figure could plausibly be as much as 2 metres.
气候变暖对冰同样有影响：冰因此融化。海冰融化会影响生态系统和水流。由于浮冰重力和它排开的水的重力相等，所以它对海平面没有影响。但是，陆地上的冰河和大冰原要是融化了，就会往海里注入大量淡水，一旦如此，海平面上升的速度还会加快，而40多年来，海平面已经以年均近2毫米的速度上升了。近来的研究表明，本世纪海平面总体上升值完全有可能达到80厘米，但就算该数据是2米也不是不可能。

The burning over the past 100 years or so of fossil fuels that took half a billion years to form has suddenly, in geological terms, put an enormous amount of carbon dioxide into the atmosphere. About a third of this CO2 is taken up by the sea, where it forms carbonic acid. The plants and animals that have evolved over time to thrive in slightly alkaline surface waters—their pH is around 8.3—are now having to adapt to a 30% increase in the acidity of their surroundings. Some will no doubt flourish, but if the trend continues, as it will for at least some decades, clams, mussels, conches and all creatures that grow shells made of calcium carbonate will struggle. So will corals, especially those whose skeletons are composed of aragonite, a particularly unstable form of calcium carbonate.
从地质学角度来说，在过去100年左右，化石燃料的使用往大气中排入大量二氧化碳，而这些化石燃料需要5亿年才能形成。1/3的二氧化碳被海洋所吸收，形成碳酸。在漫长的进化过程中，海洋动植物已经习惯了海面的弱碱性——PH值大约为8.3，但现在它们不得不去适应所处环境酸度30%的下降。有些物种会因此得到短暂繁荣，这是毫无疑问的，这种趋势至少在接下来的几十年内还会继续，但假如那时还不停止，那么，包括蛤、蚌、海螺等具有由碳酸钙形成的贝壳的贝类动物的生存就堪忧了。珊瑚礁对此也受到同样的危险，对于骨骼由霰石（极不稳定的碳酸钙）构成的珊瑚来说，情况更是如此。

Man’s interference does not stop with CO2. Knowingly and deliberately, he throws plenty of rubbish into the sea, everything from sewage to rubber tyres and from plastic packaging to toxic waste. Inadvertently, he also lets flame retardants, bunker oil and heavy metals seep into the mighty ocean, and often invasive species too. Much of the harm done by such pollutants is invisible to the eye: it shows up only in the analysis of dead polar bears or in tuna served in New York sushi bars.
二氧化碳的排放并未没有因为人类的干涉停止。尽管心知肚明，但污水、轮胎、塑料袋、有毒废物统统都往海里倒；而不经意间，又让阻化剂、燃料油、重金属流入强大的海洋，也往往进入肉食生物体内。这些污染物的害处又往往是无形的：惟有当人们对北极熊尸检，或是在纽约寿司店检验金枪鱼时，这个问题才会浮现出来。

Increasingly, though, swimmers, sailors and even those who monitor the sea with the help of satellites are encountering highly visible algal blooms known as red tides. These have always occurred naturally, but they have increased in frequency, number and size in recent years, notably since man-made nitrogen fertilisers came into widespread use in the 1950s. When rainwater contaminated with these fertilisers and other nutrients reaches the sea, as it does where the Mississippi runs into the Gulf of Mexico, an explosion of toxic algae and bacteria takes place, killing fish, absorbing almost all the oxygen and leaving a microbially dominated ecosystem, often based on a carpet of slime.
然而，由于海藻爆发生殖产生的赤潮现象，发生次数却越来越多，这是游泳者、水手、甚至是通过卫星检测海域的人有目共睹的。赤潮现象过去是自然现象，但近年来，它的频率、次数、规模都有所上升，尤其是自从上世纪50年代，人造氮肥的广泛使用以来更甚。随着受这些化肥及其他营养物污染的雨水排入大海，有毒藻类、细菌爆发性生殖，几乎将溶解氧消耗怠尽，导致鱼类死亡，生态系统为微生物所支配，这又往往是基于一层黏液的，密西西比河注入墨西哥湾也会发生这种情况。

Each of these phenomena would be bad enough on its own, but all appear to be linked, usually synergistically. Slaughter one species in the food web and you set off a chain of alterations above or below. Thus the near extinction of sea otters in the northern Pacific led to a proliferation of sea urchins, which then laid waste an entire kelp forest that had hitherto sustained its own ecosystem. If acidification kills tiny sea snails known as pteropods, as it is likely to, the Pacific salmon that feed upon these planktonic creatures may also die. Then other fish may move in, preventing the salmon from coming back, just as other species did when cod were all but fished out in Georges Bank, off New England.
就算是只针对个体，这些情况就已经很棘手了，但所有这些却存在联系，而且往往是相互促进。在整个食物链中，一旦有一个物种遭到破坏，那么上下层结构都因此发生连锁改变。所以说，北太平北部几近灭绝的海懒导致了海胆的疯长，海胆的排泄物又导致了一整片海藻森林形成，至今仍保持其自己的生态系统。又比如，海水酸化导致翼足目纲的海螺死亡，那么，以这些浮游生物为食的大鳞大麻哈鱼也会一并死亡。接着，其他鱼类就会占领该地，防止其他大麻哈鱼回来，当时新英格兰的乔治海岸的鳕几乎灭绝时也是这样的。

Whereas misfortunes that came singly might not prove fatal, those that come in combination often prove overwhelming. The few coral reefs that remain pristine seem able to cope with the warming  and acidification that none can escape, but most of the reefs that have also suffered overfishing or pollution have succumbed to bleaching or even death. Biodiversity comes with interdependence, and the shocks administered by mankind in recent decades have been so numerous and so severe that the natural balance of marine life is everywhere disturbed.
这种“倒霉事”要是单枪匹马那还算不上弥天大祸，一旦同恶相求，那就真会是灭顶之灾了。现在还没受到污染的少数珊瑚礁似乎能够应付气候变暖和海水酸化，这是谁也不能避免的，但大多数珊瑚由于过度捕捞或是污染已经产生“漂白现象”甚至死亡了。生态多样性源于相互依赖，然而近几十年来人类对其冲击太巨大，以致海洋生物的自然平衡遭到破坏的情况比比皆是。

Are these changes reversible? Most scientists believe that fisheries, for instance, could be restored to health with the right policies, properly enforced. But many of the changes are speeding up, not slowing down. Some, such as the acidification of the seas, will continue for years to come simply because of events already in train or past. And some, such as the melting of the Arctic ice cap, may be close to the point at which an abrupt, and perhaps irreversible, series of happenings is set in motion.
这些变化还有扭转的余地吗？以渔业为例，多数科学家认为，只要政策有利、实施得当，这个行业还是能够健康发展的。但是，许多变化速度有增无减。像海水酸化这类的变化，只因为事情马上就会发生或者已经发生了，这种变化就会持续数年。还有一些，比如北极冰帽融化，可能要到情况变得一发不可收拾前才能悬崖勒马，甚至可能刹都刹不住车。

It is clear, in any event, that man must change his ways. Humans could afford to treat the sea as an infinite resource when they were relatively few in number, capable of only rather inefficient exploitation of the vasty deep and without as yet a taste for fossil fuels. A world of 6.7 billion souls, set to become 9 billion by 2050, can no longer do so. The possibility of widespread catastrophe is simply too great.
无论如何，人类必须做出改变，这是显而易见的。惟有当人类数量屈指可数、对海洋开发需求寥寥无几，完全不用化石燃料时，人类才可以拍着胸脯认为海洋资源用之不竭。但对于一个人口达到67亿，2050即将达到90亿的世界，我们没有那本钱了。发生大规模灾难的可能性实在太大了。

 

译者：irini   http://www.ecocn.org/bbs/viewthread.php?tid=16502

——约翰•肯尼迪