1、A man-made world一个人造的世界Science is recognising humans as a geological force to be reckoned with 科学上已经将人看作是一个地质推动力了May 26th 2011 | from the print editionTHE here and now are defined by astronomy and geology. Astronomy takes care of the here: a planet orbiting a yellow star embedded in one of the spira
2、l arms of the Milky Way, a galaxy that is itself part of the Virgo supercluster, one of millions of similarly vast entities dotted through the sky. Geology deals with the now: the 10,000-year-old Holocene epoch, a peculiarly stable and clement part of the Quaternary period, a time distinguished by r
3、egular shifts into and out of ice ages. The Quaternary forms part of the 65m-year Cenozoic era, distinguished by the opening of the North Atlantic, the rise of the Himalayas, and the widespread presence of mammals and flowering plants. This era in turn marks the most recent part of the Phanerozoic a
4、eon, the 540m-year chunk of the Earths history wherein rocks with fossils of complex organisms can be found. The regularity of celestial clockwork and the solid probity of rock give these co-ordinates a reassuring constancy.这儿和现在是被天文学和地质学定义的。天文学关注这里：在银河的一个螺旋状的旋臂中镶嵌着一颗黄色的恒星，一颗行星绕着它运行，室女座超星系团的部分是与银河系类
5、似的一个巨大实体，它是点缀在天空中的数百万个星系之一。地质学则研究现在：1 万年之久的全新世是第四纪(Quaternary)1的一部分第四纪的特点就是冰期间冰期的有规律的交替，而全新世(Holocene)2则是一个非常稳定和温和的时期。第四纪是 6500 万年的新生代(Cenozoic)3的组成部分，在此时期，一个显著的特点就是北大西洋的诞生和喜马拉雅山的崛起，以及哺乳动物和开花植物的广泛出现。反过来讲，这个时代是显生宙（Phanerozoic） 4最为年轻的构成部分在地球 5.4 亿年以来的历史中，那些含有复杂生命体的化石都可以在这个时代找到。天体的运动规律和岩石的确凿证据给了以上说法提供了
6、有力的证明。Now there is a movement afoot to change humanitys co-ordinates. In 2000 Paul Crutzen, an eminent atmospheric chemist, realised he no longer believed he was living in the Holocene. He was living in some other age, one shaped primarily by people. From their trawlers scraping the floors of the se
7、as to their dams impounding sediment by the gigatonne, from their stripping of forests to their irrigation of farms, from their mile-deep mines to their melting of glaciers, humans were bringing about an age of planetary change. With a colleague, Eugene Stoermer, Dr Crutzen suggested this age be cal
8、led the Anthropocene“the recent age of man”.现在有一种正在发生变化改变着人类的角色定位。2000 年，著名的大气化学家保罗克鲁岑（Paul Crutzen）说，他意识到不再认为自己生活在全新世了。他说自己生活在另一个时代，一个由人改造的时代。人们向海洋底部撒网，修建的大坝阻止了泥沙的沉积，砍伐森林，灌溉农田，挖掘深达一英里的矿井，一系列的行动导致了冰川融化，人类正在进入一个星球变化的时代。克鲁岑博士和同事尤金史托莫（Eugene Stoermer）建议将这个时代称作是人类世（Anthropocene）5“一个新的人类时代”。The term has
9、slowly picked up steam, both within the sciences (the International Commission on Stratigraphy, ultimate adjudicator of the geological time scale, is taking a formal interest) and beyond. This May statements on the environment by concerned Nobel laureates and the Pontifical Academy of Sciences both
10、made prominent use of the term, capitalizing on the way in which it dramatises the sheer scale of human activity.这个词已经慢慢地被接受，在科学领域（国际地层委员会最终将其作为一个地质时代的名称，正式使用）以及科学领域之外都受到了关注。今年的五月份，由诺贝尔将获得者和罗马教皇科学院(Pontifical Academy of Sciences)关注的有关环境方面的表述都充分地使用了这个术语，它强调一种人类活动的强烈方式。The advent of the Anthropocene p
11、romises more, though, than a scientific nicety or a new way of grabbing the eco-jaded publics attention. The term “paradigm shift” is bandied around with promiscuous ease. But for the natural sciences to make human activity central to its conception of the world, rather than a distraction, would mar
12、k such a shift for real. For centuries, science has progressed by making people peripheral. In the 16th century Nicolaus Copernicus moved the Earth from its privileged position at the centre of the universe. In the 18th James Hutton opened up depths of geological time that dwarf the narrow now. In t
13、he 19th Charles Darwin fitted humans onto a single twig of the evolving tree of life. As Simon Lewis, an ecologist at the University of Leeds, points out, embracing the Anthropocene as an idea means reversing this trend. It means treating humans not as insignificant observers of the natural world bu
14、t as central to its workings, elemental in their force.即便如此，人类世的到来预示着一个科学的精确或者是一个吸引处于生态衰弱中民众的注意力的新途径。思维转换这个术语经常用于各种降低的意思。不过自然科学让人类的活动更集中在这个领域内，而不是分散到了其他领域，这标志着一个现实世界的转变。16 世纪哥白尼（Nicolaus Copernicus）的理论推翻了地球是宇宙中心特别位置的说法。18 世纪的詹姆斯赫顿（ James Hutton）开辟了地质时代的深度，现在这个研究范围已经很窄了。19世纪达尔文（Charles Darwin）将人单独作为进
15、化树的一个分支。还有就是西蒙刘易斯（Simon Lewis） ，这个英国利兹大学（Simon Lewis）的生态学家指出，人类世这个理念的包含内容意味着这种趋势的转变。这意味着，不能将人作为自然界的一个无足轻重的旁观者，而是将其作为整个自然界的中心，并且是最为重要的力量。The most common way of distinguishing periods of geological time is by means of the fossils they contain. On this basis picking out the Anthropocene in the rocks of
16、 days to come will be pretty easy. Cities will make particularly distinctive fossils. A city on a fast-sinking river delta (and fast-sinking deltas, undermined by the pumping of groundwater and starved of sediment by dams upstream, are common Anthropocene environments) could spend millions of years
17、buried and still, when eventually uncovered, reveal through its crushed structures and weird mixtures of materials that it is unlike anything else in the geological record.判断地质时代的最常用方法就是通过研究化石中所包含的信息。以此为基础，挑出人类世那个时代的岩石就相当容易了。城市在这个方面尤为明显。在一个快速下沉的河流三角洲（在地下水被不停地抽走和大坝上游对于泥沙的阻挡的前提下，三角洲会遭到破坏，这是一个人类世很普遍的环境
18、）上的城市，在几百万年后就有可能被埋没，不过最终通过它破碎的结构和独特的材料混合物仍然可以发现它，因为这些材料与地质编录6内容的非常不同。The fossils of living creatures will be distinctive, too. Geologists define periods through assemblages of fossil life reliably found together. One of the characteristic markers of the Anthropocene will be the widespread remains of
19、 organisms that humans use, or that have adapted to life in a human-dominated world. According to studies by Erle Ellis, an ecologist at the University of Maryland, Baltimore County, the vast majority of ecosystems on the planet now reflect the presence of people. There are, for instance, more trees
20、 on farms than in wild forests. And these anthropic biomes are spread about the planet in a way that the ecological arrangements of the prehuman world were not. The fossil record of the Anthropocene will thus show a planetary ecosystem homogenised through domestication.生物的化石同样也独一无二的。地质学家通过将发现的有明显生命信
21、息的化石归类，研究这些化石的集合来定义地质时期。人类世的特征之一就是有机物的广泛使用，或者说是适应人类点主导地位世界的生活。马里兰大学巴尔的摩分校的生态学家艾勒艾丽斯（Erle Ellis）研究表明， 现在地球上的大部分生态系统都反应了人类的活动。例如，农田的树木比野生森林的更多。并且人为的生物群落的分布比人类出现前生态分布更为广泛。人类世的地质编录将因此显示，通过人类的活动，地球的生态系统被同质化了。More sinisterly, there are the fossils that will not be found. Although it is not yet inevitable,
22、 scientists warn that if current trends of habitat loss continue, exacerbated by the effects of climate change, there could be an imminent and dramatic number of extinctions before long.更悲剧的是，还有一些不会被发现的化石。虽然这还不会必然发生，不过科学家警告说，在气候变暖的影响下，如果按照目前栖息地丧失的趋势加剧的话，不久就可能出现物种数量的锐减。All these things would show fut
23、ure geologists that humans had been present. But though they might be diagnostic of the time in which humans lived, they would not necessarily show that those humans shaped their time in the way that people pushing the idea of the Anthropocene want to argue. The strong claim of those announcing the
24、recent dawning of the age of man is that humans are not just spreading over the planet, but are changing the way it works.所有的这一切将会摆在未来的地质学家面前，将带给他们曾经人类的信息。不过他们或许能推断中当时人类生存的时代，不过他们未必能够了解当时的人类是以什么方式来改造那个时代的，这会使未来的地质学家为人类世的有关想法而争论。最近有关人类的时代的强烈声明都表明，人类不仅遍布全球，并且还在改变着地球的作用方式。Such workings are the province
25、 of Earth-system science, which sees the planet not just as a set of places, or as the subject of a history, but also as a system of forces, flows and feedbacks that act upon each other. This system can behave in distinctive and counterintuitive ways, including sometimes flipping suddenly from one s
26、tate to another. To an Earth-system scientist the difference between the Quaternary period (which includes the Holocene) and the Neogene, which came before it, is not just what was living where, or what the sea level was; it is that in the Neogene the climate stayed stable whereas in the Quaternary
27、it swung in and out of a series of ice ages. The Earth worked differently in the two periods.这样的工作是地球系统科学领域的事情，该学科不仅将地球看作是一系列的地理概念或者说一个历史范畴的事物，而此将其看作是一个作用力，河流以及二者之间的反馈系统。这个系统以是一种独特以及不可思议的方式运行着，有时候它会突然从一个状态变到另一个状态。对于一个地球系统科学家来说，比第四纪7（包括全新世）与晚第三纪 8（Neogene）的区别更重要的是，不仅在于生物及其生存地点的差异，而且还在于其海平面的不同；新第三纪的气候
28、很稳定，而第四季却很屡次出现冰川时期9。在这两个时期间，地球的运作方式有所不同。The clearest evidence for the system working differently in the Anthropocene comes from the recycling systems on which life depends for various crucial elements. In the past couple of centuries people have released quantities of fossil carbon that the planet t
29、ook hundreds of millions of years to store away. This has given them a commanding role in the planets carbon cycle.人类世运作方式与以往的时代有很大的不同，其中最为明显的标志就是地球上生命所依赖的各种重要的元素循环。在过去的数百年间，人类排放了大量的化石中的碳，而这些碳在数亿年间都被地球储存了起来。这些碳在全球的碳循环中起到了一个决定性的作用。Although the natural fluxes of carbon dioxide into and out of the atmo
30、sphere are still more than ten times larger than the amount that humans put in every year by burning fossil fuels, the human addition matters disproportionately because it unbalances those natural flows. As Mr Micawber wisely pointed out, a small change in income can, in the absence of a compensatin
31、g change in outlays, have a disastrous effect. The result of putting more carbon into the atmosphere than can be taken out of it is a warmer climate, a melting Arctic, higher sea levels, improvements in the photosynthetic efficiency of many plants, an intensification of the hydrologic cycle of evapo
32、ration and precipitation, and new ocean chemistry.与大气中碳的自然流量相比，人类每年通过燃烧化石燃料向其中排放的二氧化碳只是前者的十分之一，不过人类的影响却不成比例在增加，因为人类打破了自然界碳循环的平衡。米考伯（Micawber ）就曾睿智地指出，在输出没有一个补偿性的变化下，碳输入中的一个小的增长就会造成一个灾难性的影响。向大气中输入比它排出量更多的碳，就会造成气候变暖，北极融化，海平面升高，众多植物光合作用效率的提高，蒸发与降水之水文循环加剧，还有就是新海洋化学的产生。All of these have knock-on effects
33、both on people and on the processes of the planet. More rain means more weathering of mountains. More efficient photosynthesis means less evaporation from croplands. And the changes in ocean chemistry are the sort of thing that can be expected to have a direct effect on the geological record if carb
34、on levels rise far enough.所有的这些都对地球的进程和人类产生了连锁的影响。更多的降雨着更多的山区会遭到侵蚀。更高效的光合作用效率着农田蒸发的减少。如果碳浓度上升得足够高，则大洋中化学成分的改变可以预料到会对地质编录产生直接的影响。At a recent meeting of the Geological Society of London that was devoted to thinking about the Anthropocene and its geological record, Toby Tyrrell of the University of Sou
35、thampton pointed out that pale carbonate sedimentslimestones, chalks and the likecannot be laid down below what is called a “carbonate compensation depth”. And changes in chemistry brought about by the fossil-fuel carbon now accumulating in the ocean will raise the carbonate compensation depth, rath
36、er as a warmer atmosphere raises the snowline on mountains. Some ocean floors which are shallow enough for carbonates to precipitate out as sediment in current conditions will be out of the game when the compensation depth has risen, like ski resorts too low on a warming alp. New carbonates will no
37、longer be laid down. Old ones will dissolve. This change in patterns of deep-ocean sedimentation will result in a curious, dark band of carbonate-free rockrather like that which is seen in sediments from the Palaeocene-Eocene thermal maximum, an episode of severe greenhouse warming brought on by the
38、 release of pent-up carbon 56m years ago.在最近一次的伦敦地质学会会议上，专门讨论了人类世及其地质编录。南安普敦大学的托比 泰利尔（Toby Tyrrell）指出，灰白色的碳沉积物石灰石，粉笔等类似的东西不能放在“碳酸盐补偿深度”10概念之下。现在化石燃料中的碳导致的化学物变化会提高海洋中的碳酸盐补偿深度，就像一个更加温暖的大气会增加高山雪线的高度一样。这类似于滑雪胜的高山比较低一样，当补偿深度上升时，当前的条件也将会失控，一些海洋底部对于碳酸盐积淀来说已经相当浅了。新的碳酸盐将不再沉淀。旧的碳酸盐将会溶解。这种在深海沉积物上的变化将会导致一个奇怪的，黑
39、色的非碳酸盐岩石带这就像古新世11-始新世12（Palaeocene-Eocene）极热事件13一样，5600 万年前，由于释放了积压已久的碳，发生了一个非常严重的温室效应事件。The fix is in 元素固定No Dickensian insights are necessary to appreciate the scale of human intervention in the nitrogen cycle. One crucial part of this cyclethe fixing of pure nitrogen from the atmosphere into usef
40、ul nitrogen-containing chemicalsdepends more or less entirely on living things (lightning helps a bit). And the living things doing most of that work are now people (see chart). By adding industrial clout to the efforts of the microbes that used to do the job single-handed, humans have increased the
41、 annual amount of nitrogen fixed on land by more than 150%. Some of this is accidental. Burning fossil fuels tends to oxidise nitrogen at the same time. The majority is done on purpose, mostly to make fertilisers. This has a variety of unwholesome consequences, most importantly the increasing number
42、 of coastal “dead zones” caused by algal blooms feeding on fertiliser-rich run-off waters.在理解人类对氮循环的干扰力度方面，并非是杞人忧天。氮循环的一个关键组成部分就是在大气中，将纯净的氮固定为成含氮化合物的形式这或多或少要完全依赖于生物（闪电仅起一点儿作用） 。并且生物和人做了其中的大部分工作（看图表） 。过去是微生物单独进行固氮工作，而现在通过引入受到工业化改造的微生物，人类在陆地上的固氮量增加了 150%。其中的一些是偶然的。与此同时，燃烧化石燃料也有增加氮的氧化物的趋势。以上这样做的目的大多数是为
43、了制造肥料。这会造成很多不健康的后果，其中最为显著的就是那依赖于寻些富营养水生存的藻类造成的沿海“死区”数量的增加。Industrial nitrogens greatest environmental impact, though, is to increase the number of people. Although nitrogen fixation is not just a gift of lifeit has been estimated that 100m people were killed by explosives made with industrially fixe
44、d nitrogen in the 20th centurys warsits net effect has been to allow a huge growth in population. About 40% of the nitrogen in the protein that humans eat today got into that food by way of artificial fertiliser. There would be nowhere near as many people doing all sorts of other things to the plane
45、t if humans had not sped the nitrogen cycle up.不过工业氮造成的是最大环境影响就是人类数量的增加。即便固氮不是生命的礼物据估计，在 20 世纪的战争中，由于工业固氮的爆炸，有 1 亿人被剥夺了生命但其净影响就是造成了巨大的人口增长。现在人类所吃食物的蛋白质中，大约其中 40%的氮的的来源都是人工肥料。如果人类没有加速氮循环的速度，那么就远不会有众多人对地球上做其他的各种事情。It is also worth noting that unlike many of humanitys other effects on the planet, the r
46、emaking of the nitrogen cycle was deliberate. In the late 19th century scientists diagnosed a shortage of nitrogen as a planet-wide problem. Knowing that natural processes would not improve the supply, they invented an artificial one, the Haber process, that could mak desired up the difference. It w
47、as, says Mark Sutton of the Centre for Ecology and Hydrology in Edinburgh, the first serious human attempt at geoengineering the planet to bring about a desired goal. The scale of its success outstripped the imaginings of its instigators. So did the scale of its unintended consequences.还值得注意的是，与地球上其
48、他人类的影响不同，对于氮循环的再改造是故意的。在 19 世纪晚期，科学家断定，缺氮将成为一个全球性的问题。当了解到自然的过程不会提高氮的供应后，人们发明了人工固氮的方法，即哈伯的工艺路线（Haber） ，这弥补了氮的不足。位于爱丁堡的生态与水文研究中心的马克萨顿（Mark Sutton）说， ，这是人类第一次在地球工程上为了一个明确的目标而进行的努力。它的巨大成功远远超出其最初设想者的想象。当然其想到的后果也是超出预料的。For many of those promoting the idea of the Anthropocene, further geoengineering may no
49、w be in order, this time on the carbon front. Left to themselves, carbon-dioxide levels in the atmosphere are expected to remain high for 1,000 yearsmore, if emissions continue to go up through this century. It is increasingly common to hear climate scientists arguing that this means things should not be left to themselvesthat the goal of the 21st century should be not just to stop the amount of carbon in the atmosphere increasing, but to start actively decreasing it. This might be done in part by growing forests (see a
