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2019年09月17日 10:31:51来源:养心媒体

Science and Technolgy科技Invasive species入侵物种Boom and bust繁衍与湮灭Invasive Argentine ants may be less persistent than once feared入侵性阿根廷蚂蚁可能没有想象的那么可怕DESPITE their name, Argentine ants are a well-travelled lot. Human commerce has allowed them to hitch rides from their homeland to every continent on the planet, with the exception of Antarctica. And when they arrive, they often thrive. At least 15 countries now host colonies, which frequently prosper at the expense of native species. This flexibility, combined with an aggressive temperament, makes them one of the worlds best-known and most-hated invasive species.如果不顾它们的恶名,阿根廷蚂蚁可以说是很好的旅行家。人类的商业活动将它们带到了世界各大洲,南极洲除外。并且当它们到达时,它们就会繁衍。目前,至少15个国家受到外来物种的入侵,这种入侵是以牺牲本土物种为代价的。这种侵略性及适应性使得它们成为世界上最著名同时也是最令人深恶痛绝的入侵物种。Yet, as any general knows, establishing a beachhead is not the same thing as conducting a successful, long-term occupation. Argentine-ant colonies sometimes collapse suddenly, and with no obvious explanation. In a paper just published in Biology Letters, a group of researchers at Victoria University of Wellington, in New Zealand, led by Meghan Cooling and Phil Lester, describe their attempts to study such disappearances systematically.但是,众所周知,建立一个滩头阵地不同于成功地进行一次长期占领。阿根廷蚂蚁的入侵有时突然毫无缘由地停止。在最近发表在《生物书简》(Biology Letters)上的一篇文章中,新西兰惠灵顿维多利亚大学(Victoria University of Wellington)的一组研究人员——由梅根?库灵(Meghan Cooling)和菲尔?莱斯特(Phil Lester)领导——描述了他们对这种系统性消失的研究。The researchers examined 150 sites across the country where Argentine-ant nests had been recorded. At 40% of them they found that the ants had vanished. At many of the other sites, ant numbers were much reduced, with areas that once sported dozens of nests over hundreds of hectares reduced to just one or two colonies covering much smaller tracts of land. And with the invaders gone, native ants seemed to be re-establishing themselves, suggesting that the Argentine ants impact on biodiversity had been transient, rather than permanent.研究者们考察了全国范围内150个已经被记录下来的阿根廷蚂蚁据点。他们发现其中的40%已经消失,而在其他的据点,蚂蚁数量减少,原来几百公顷的面积上有几十个蚁巢,而现在一片小面积土地上只有一两个聚居群。随着侵略者离开,本土蚂蚁似乎在重建自己的种群,这表明阿根廷蚂蚁对生物多样性的影响只是暂时的。A statistical analysis of the data yielded an estimate for the likely survival time of a typical colony of between 12.9 and 15.3 years, and suggested that warm and dry conditions were more favourable for survival than cold, wet ones. Exactly what caused the collapses is still not clear, although the researchers suspect that unfamiliar diseases may have played a role.数据统计分析估测了一个典型的聚居群(12.9—15.3年)可能的生存时间。该分析也表明,比起寒冷潮湿的条件,温暖干燥的环境更有利于生存。尽管研究者们怀疑不熟悉的疾病可能起到了一定作用,但导致阿根廷蚂蚁消失的确切原因尚不清楚。y is not strength团结不是力量It is a plausible theory. Because they grew from a small number of founder colonies, or possibly even a single one, New Zealands Argentine ants are genetically similar to one another (the same is true of most infestations outside the ants homeland). That may be one reason for their success: ant researchers hypothesise that, being so closely related, the individual insects are unable to distinguish their nest mates from members of other colonies, which causes ants from different nests to co-operate as if they were kin, and has led students of the field to speak not of hundreds of individual infestations, but of a single, country-spanning ;super-colony;.这种理论可信。因为它们是从很小的群体(或者可能是单一个体)发展起来的,新西兰的阿根廷蚂蚁之间的基因非常相似(蚁巢以外的侵扰也同样具有该特点)。这也许是它们成功的原因之一:蚂蚁研究者假定,关系紧密的个体昆虫不能够把同巢穴的同伴同其它聚居区的成员区分开来,这导致来自不同巢穴的蚂蚁就像亲戚一样相互合作。这使得这一领域的学者不再谈及成百的个体侵扰,而是谈及单一的、跨越全国的;超级群体;。But a shallow gene pool can be a weakness, too. If one nest proves susceptible to some environmental factor-be it disease, predation, or even a cold snap or wet spell-then it is likely that all the other colonies will share that vulnerability.但是,一个浅薄的基因库也可能是一个弱点。如果一个巢穴容易受到某些环境因素的影响——不管是疾病、掠食,亦或是寒流、潮湿期——那么极可能其他的聚居群也有着同样的弱点。Now that they have documented the extent of the collapse the next step, says Ms Cooling, is to test the hypothesis of genetic vulnerability and try to work out precisely what causes the sudden reversals of formicine fortune she has seen. And it is not just ecologists who will be waiting for the results. New Zealands government had reckoned it might have to spend NZm (m) a year keeping the newcomers under control. If Mother Nature can do the job instead, then it would represent a tidy saving for the countrys exchequer.库灵表示,他们现在已经记载了蚁群消失的范围,下一步是验基因脆弱性这一假设,并努力找出导致蚁群突然转变的确切原因。而等待这一结果的不止是生态学家。新西兰政府估计,每年可能会花掉NZm(合m)用于控制新物种的入侵。如果自然母亲能够完成这项工作,那将会为国库省下一大笔资金。 /201210/202576。

  • IN 1989 Edward Kennedy tried to stop time. The ed States Coast Guard was preparing to automate and remove all remaining personnel from the old lighthouse in Boston Harbour. But Kennedy, a liberal senator from a family with deep roots in Boston, sponsored a bill requiring the Boston Light to be permanently manned. And so it soldiered on for nearly another decade, stubbornly holding to the old ways. Built in 1783, it is one of America’s oldest lighthouses (the oldest was its predecessor, which the British blew up as they slunk home in June 1776). In 1998 time and Senator Kennedy reached a compromise: the light itself was at last automated, but it remains the last one with resident Coast Guard keepers.爱德华.肯尼迪试图让时间定格1989年。当时,美国海岸防卫队正准备从波士顿港撤走所有留守人员,实现灯塔全自动化。然而与波士顿有着深厚渊源的自由派参议员肯尼迪,提出了一份议案,要求派人长期驻守灯塔。因此,灯塔由士兵守候了又是近十年光景,这样灯塔顽强地得以维持其原状。兴建于1783年的波士顿灯塔(其前身是美国最古老的灯塔,1776年6月英国人仓惶归国时,将其炸毁)是美国最古老的灯塔之一。经过长期的争取,肯尼迪最终于1998年出台了一项折衷方案:波士顿灯塔最终实现自动化,而且也是全美唯一一座由海岸警卫队驻守的灯塔。The Coast Guard took charge of America’s more than 1,000 lighthouses in 1939, when it absorbed the ed States Lighthouse Service. But it has been slowly letting them go. In 2000 the National Historic Lighthouse Preservation Act allowed the sale or transfer of lighthouses deemed “excess to service requirements” by the Coast Guard to private entities. Since then the federal government has moved 84 lighthouses of the 600 that were left off its books. Most have been transferred to local governments or non-profits, but 28 have been auctioned off to private individuals.1939年,美国灯塔划归到海岸警卫队。自那以后,海岸警卫队负责管理美国1000多座灯塔。但渐渐地,美国海军看护的灯塔越来越少。2000年《国家历史灯塔保存法案》允许海岸警卫队将那些被认为是“其务已不再必要”的灯塔出售或转让给私有个体。从此,美国联邦政府出售转让了书中记载的仅存的600座灯塔中的84座。大部分灯塔转交给当地政府或非营利机构,但28座灯塔已被拍卖给个人。The sad truth is that satellite navigation has made many lighthouses surplus to requirements. Shifting commercial trends have done their damage, too. More than 1,500 ships lie wrecked off North Carolina’s Outer Banks, but today these islands depend far more on tourism than on maritime trade.遗憾的是,现在有了卫星导航技术,好多灯塔根本就用不上了。贸易趋势的转变也让灯塔越来越没有用武之地。北卡罗来纳州外班克斯港有1500多艘触礁的船只残骸,然而今天这些岛屿主要依靠旅游业而不是海上贸易。Still, some fishermen enjoy navigating by light rather than satellite. Sometimes they forget to take their navigation systems on board. Bett Padgett, who heads the Outer Banks Lighthouse Society, which petitioned the federal government for funds to restore Bodie Island’s once-crumbling lighthouse, warns of solar flares knocking out satellites.然而,有许多渔民仍然喜欢利用灯塔而不是卫星来导航,所以有时候,他们会忘记带导航系统。外班克斯列岛灯塔协会(该协会曾请求联邦政府拨款整修一度年久失修的Bodie灯塔)会长Bett Padgett提醒人们太阳耀斑会让卫星暂时失灵。All that is true, but defending lighthouses as a matter of utility surely misses the point.。 Of course, lighthouses draw tourists, who spend money; one informal study estimated that restoring the Bodie Island lighthouse, which is scheduled to open to visitors for the first time in April 2013, would add .7m in total income to the regional economy.But for Ms Padgett, preserving them is a way “to give our children and grandchildren a feel for what happened in this place a hundred or two hundred years ago.” Men built them by hand to stand watch over the sea. Lighthouses remind people that as mariners battled what Walt Whitman called “the wild unrest, the snowy, curling caps—that inbound urge and urge of waves, Seeking the shores forever,” someone was watching over them, and wishing them safely home.上面说的没错,但从实用性角度为灯塔辩护,显然没有说到关键之处。当然,灯塔吸引了大批来此消费的游客;一项非官方调查预计修整 Bodie灯塔将为当地经济带来总计870万美元的收入,该灯塔预计于2013年4月首次向游客开放。但在Padgett女士看来,保存好灯塔是让“我们子孙感受一两百年来这里变迁”的一种方式。人们建造灯塔来让它们守候大海。灯塔让人们想到,当水手们与沃尔特.惠特曼笔下“那永不宁静的奔腾,那白浪般的滚卷的浪峰----那向陆地急推又急推的浪头“搏斗时,有人在灯塔上眺望,盼望他们安全归来。201204/177262。
  • Business Mongolian copper Halfway to where?商业 蒙古铜矿 半程去何方?彷徨,宝石山下倚彤妆A massive mining project hits a snag一个庞大的矿业项目遭到意外困难IN THE endless brown wastes of the Gobi desert in the south of Mongolia huge blue structures are springing up.在蒙古南部一望无际的棕色戈壁沙漠荒原上,庞大的蓝色建筑物拔地而起。Some 18,000 workers are employed on Oyu Tolgoi, or ;Turquoise Hill;, the largest undeveloped copper and gold mine in the world.大约18,000名员工为世界上尚未开采的最大铜金矿山,奥尤陶勒盖(意为;绿宝石山;)工作。Rio Tinto, the mining giant that is managing the project, flew its chairman, Jan du Plessis, to the site for a ceremony on September 25th to mark the halfway point of the first phase of construction.正在经管这一项目的采矿业巨头力拓公司的董事长杜立石飞临现场,参加了9月25日的一项庆典,这标志着矿山建设的第一阶段已经完成了一半。Celebrations were hardly marred by rumblings of discontent back in the capital, Ulaanbaatar, from Mongolian politicians.这些庆祝几乎没有受到来自首都乌兰巴托的蒙古政治家们不满叫嚣的干扰。But since then the rumblings have got louder, worrying not just Oyu Tolgois investors, but all those gleeful at the prospect of a prolonged mining-led boom in the country.但从那时起叫嚣声变得更为响亮了,对此感到担忧的不仅是奥尤陶勒盖的投资方,还有所有因采矿业为这个国家带来的长期繁荣前景感到兴高采烈的人们。A group of 20 members of parliament signed a petition in early September asking the government to reopen negotiations on the ;Investment Agreement; that set the billion project in motion.9月初,20名国会议员在一份请愿书上签字,要求政府就年的;投资协议;——这一协议启动了这项耗资一百亿美元的项目——重开谈判。That could be dismissed as populist political noise ahead of elections due next year.人们可以把这当作为明年大选造势的平民主义政治喧嚣而不予理会。But by the end of the month, it had become the basis of a formal request from the government to Ivanhoe Mines of Canada, which has a 66% stake in the company that owns the mine and is in turn 49% owned by Rio.但到9月末,这已经成了政府向加拿大艾芬豪矿业公司提出的正式要求的基础;力拓公司持有艾芬豪公司49%的股份,而后者则持有这座矿山的拥有者公司中66% 的股份。Opening parliament this week, the speaker, who sits on the National Security Council, voiced his support for a renegotiation.本周宣布议会开幕的议长——他也是国家安全委员会的成员——表示持重开谈判。The main demand is to bring forward the date when the government has the option to increase its 34% share in the project to 50%.他们的主要要求,是让政府可以提前选择将其在此项目中的股份由34%增加到50%的时间。At present, its share—which was financed by a loan from Rio—cannot rise until 2040.根据现有协议,政府的股份——由力拓的一项贷款提供资金——要到2040年才可以增加。The government also wants to impose a ;sliding-scale royalty; on the project.与此同时,政府想对这一项目征收;浮动权利金;。This week, Ivanhoe and Rio shot back a letter saying the agreement was not up for renegotiation.艾芬豪与力拓本周在回信中声称该协议没有谈判余地。All they will concede is that, under its terms, the government is within its rights to ask for talks. They are adamant, however, that the terms cannot be changed.他们做出的仅有让步是,政府有权按照协议规定要求对话。但他们认定,协议条款绝无更改可能。The mining companies point out the huge benefits the project brings in terms of employment, tax revenue and foreign exchange.这两家矿业公司指出了这一项目在就业、税收与外汇方面带来的庞大利益。By 2020, when it will be producing 450,000 tonnes of copper a year, which will be sold across the nearby Chinese border, it is expected to account for a staggering one-third of Mongolias GDP.当2020年矿山年产铜量达到450,000吨时,这些铜可以向不远处的中国出口,预期可占蒙古全国GDP的三分之一,一个令人惊叹的数字。They also argue that, with the copper price falling, a renegotiation might leave the government in a worse position.他们还认为,随着铜价下跌,重开谈判可能对政府不利。The current agreement has the effect of insuring its equity stake against market risk.现有的协议具有保其股权不受市场风险影响的作用。The investors feel some Mongolians do not understand that, because of taxes and royalties, the governments 34% share grossly understates the benefits it will receive from the project.投资者们感到,由于在税收与权利金上的收益,政府从这一项目得到的好处将远远超过表面上34%的股份,而一些蒙古人对此并不清楚。Oyu Tolgoi is the poster project for a national mining boom that sees Ulaanbaatar crawling with foreign miners and their investment bankers.奥尤陶勒盖是国家矿业兴隆的一个招牌式项目,它让外国矿业公司和他们的投资一起涌入乌兰巴托。Of immediate concern are plans to raise billions of dollars through a multinational offering of shares in a huge coal project, Tavan Tolgoi, also in South Gobi province.当前人们关心的,是以一个庞大煤矿项目的股权面向多国集资筹措数十亿美元的计划;该煤矿名为塔班陶勒盖,也位于南戈壁省。Oyu Tolgoi aly faces problems enough.奥尤陶勒盖面临的麻烦已经够多的了。Inter-governmental negotiations with China have yet to produce an agreement on its supply of power for the early years of production.与中国举行的政府间谈判尚未达成投产初期一些年内由中国提供电力的协议。Ivanhoe has been snapping at Rio for making ;unauthorised remarks; about the project, and there is the small matter of billion in bank finance to be raised.艾芬豪一直对力拓有关这一项目的;非正式;十分不满,另外还有筹集四十亿美元贷款的小事。So the government needed a face-saving way out of the latest fine mess it had gotten the project into.因此,政府需要以一种体面的方式摆脱他们造成的这一项目的最新尴尬局面。On October 6th it issued a joint statement with the foreign partners saying they had settled their differences, without amending the Investment Agreement. 10月6日他们与外国合伙人发表了一项联合声明,宣称各方已在不修改投资协议的情况下达成了一致。Rio and Ivanhoe will be relieved.力拓和艾芬豪可以安心了。But it will still have to deal with the disgruntled parliamentarians, not to mention voters.但心怀不满的国会议员还是需要安抚,更遑论选民们了。 /201301/218111。
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