科学家：地球迈入新地质时代 ─ 人类世（Anthropocene） 2010.03.28 中央社 http://tw.news.yahoo.com/article/url/d/a/100328/5/22vxc.html 译者：中央社蔡函岑 科学家宣称，地球已进入新的地质时期，即新人类纪元。人类已对地球造成非常广 泛而前所未见的变化，我们可能正迈入地质史上的新阶段。 据英国「每日电讯报」（Daily Telegraph）报导，科学家认为，由於环境污染、人 口暴增、都市化、人类移动、大量采矿、以及化石燃料的使用；人类已彻底改变地 球生态，势必会影响到未来数百万年。 专家忧心，人类对地球造成的伤害，将导致地球史上第六次大规模物种灭绝，数以 千计的动、植物将不复存在。 这个称为「人类世」（Anthropocene）的新时代，将成为单一物种行为所形塑的的 第一个地质时期。「人类世」原意是指新人类。 尽管科学家早已非正式的使用「人类世」一词长达10多年，科学界正考虑要将该词 正式端上台面。 专家已组成工作小组，负责蒐集各种证据，证明地质时代将从现今的「全新世」（ Holocene）进入「人类世」。 专家小组将考量人类活动对地球造成的影响，包括生物多样性、岩石结构、以及污 染和采矿等其他因素的冲击。 专家小组希望未来三年内能够将研究成果提交到「国际地质科学联合会」（Inter- national Union ofGeological Sciences, IUGS），再由该会裁定地球是否已进入 新地质时期。 这项理论是由一科学家小组所提出，该小组成员包括诺贝尔化学奖得主克鲁岑（Paul Crutzen）。 科学家小组在研究中作出以下结论：「人类世在人类史上和地球史上都代表着新的 发展阶段，此时自然力量和人类力量紧密相连，因而两者命运休戚与共。就地质学 而言，这是地球史上相当显着的事件。」 ------------------------------------------------------------------------------ Not Set in Stone Astrobiology Magazine/ Geology Summary: For the past 12,000 years, the Earth's climate has been relatively stable and hospitable. That time - the Halocene epoch - may be coming to an end as a new period in geologic history begins. Welcome to the Anthropocene - the "human epoch". http://www.astrobio.net/index.php?option=com_retrospection&task=detail&id=3446 Welcome to the Anthropocene – the “human epoch.” Geological time may seem set in stone, and certainly it has been (as far as we've defined it) for the past 12,000 years in the Holocene. But the Holocene's relatively stable interglacial climate, so hospitable that it allowed the rise of human civilization, seems to be coming to a close. Geologic epochs are typically defined by distinctive changes in sedimentary layers. So what makes these days geologically different? Well, long after we're all gone, a million years into the future, some intelligent life would be able to see clear signs of human activity in the same layers of soil across the globe. http://www.astrobio.net/blog/wp-content/uploads/2010/03/Anthropocene- Zalasiewicz-GSA1feb08f1.gif Environmental changes during the Holocene Epoch show the beginnings of dramatic spikes, marking the would-be Anthropocene. Graph courtesy of authors Jan Zalasiewicz, et. al. To show up, the disturbance has to be on a massive scale, and in fact it is. Climate change, mass extinctions, soil erosion, cleared land, pollution, radioactive isotopes from nuclear tests, sea level rise: all these human- induced changes are producing clear patterns of change that are being documented in the soil. Anthropocene has been used informally, starting with Nobel Prize winning chemist Paul Crutzen, who in 2002 coined the phrase quite unwittingly at a conference where, according to his quote in the Encyclopedia of Earth: “… someone said something about the Holocene. I suddenly thought this was wrong. The world has changed too much. So I said: ‘No, we are in the Anthropocene.’ I just made up the word on the spur of the moment. Everyone was shocked. But it seems to have stuck.” In February 2008, a GSA Today article (a monthly publication by the Geological Society of America) made the case for making the anthropocene epoch official among geologists. It nicely tracks the way human activity has made its mark in the geologic record, from mid-Holocene biotic evidence of weed pollen and the remains of cultivated plants in human settlement areas, to a layer of lead pollution that has settled in the polar ice caps and peat bog deposits from the Greco-Roman times onward. The authors write: “Human activity then may help characterize Holocene strata, but it did not create new, global environmental conditions that could translate into a fundamentally different stratigraphic signal. ” That only began to happen during the Industrial Revolution, which resulted in dramatic erosion due to expanded agriculture and construction, the damming of most major rivers thereby changing sedimentary patterns, waves of extinction and the replacement of natural vegetation with agricultural monocultures, ocean acidification, and, of course, a spike in carbon dioxide levels. http://www.astrobio.net/images/galleryimages_images/Gallery_Image_6224.jpg Change in sea surface pH caused by anthropogenic CO2 between the 1700s and the 1990s. Credit: Wikipedia Commons A temperature rise of between 2 degrees to 11.5 degrees Fahrenheit, as predicted under climate change models, hasn't been seen since the Tertiary period 66 million years ago, when mammals replaced reptiles as the predominant vertebrates, the article states. The first step towards making Anthropocene official is to select a date when it begins — not exactly an easy task considering that human impact hasn't be uniform across the globe throughout history. Does it make sense to start at the launch of Industrial Revolution in the West? One clear sign that we're already deep into the Anthropocene is that we talk, not only about human destruction of the Earth, but also contemplate ways to fix it through geo-engineering. Wired this month ran a book review of Hack the Planet by Eli Kintisch about embracing our “God role” since things have so changed so much that “stewardship” is no longer an option. --

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