- == 系统问题，暂停聊天功能。==
- 【征集】西西河的经济学，及清流措施，需要主动参与者，『稷下学宫』新认证方式，24年网站打算和努力目标
主题：白鳍豚绝种了？ -- 巴山夜雨
家园 白鳍豚绝种了？ 今天看到新闻，说科学家在长江中进行了搜索，断定中华白鳍豚已经绝种。真是太悲哀了。
- 复 白鳍豚绝种了？
家园 看看science 杂志是如何报道这次考察的 请留意最后一句话，动物学家的无奈
"It seems the baiji is the only thing that is not made in China anymore," says Pitman.
题外的一个问题：如果某些杂志上的原文大多数网友都不能看到全文，贴出来算不算违反了“反文摘法”？？？？？
Science 22 Dec 2006 1860
WILDLIFE CONSERVATION:
River Dolphins Down for the Count, and Perhaps Out
Jerry Guo*
The world's rarest cetacean is nowhere to be found. Last week, a 3500-kilometer survey along China's Yangtze River failed to turn up a single river dolphin, or baiji (Lipotes vexillifer). "It's going to take a rescue effort of epic proportions to save this species," says Karen Baragona, director of the World Wildlife Fund's China programs. But it may already be too late for the nearly blind, pale creature. Expedition organizer August Pfluger, head of the Swiss-based baiji.org Foundation, says bluntly: "The baiji is functionally extinct."
Unhappy hunting. Expedition members search fruitlessly for signs of baiji on the hazy Yangtze River. The last baiji in captivity (inset) died in 2002.
CREDITS: BARBARA TAYLOR/NOAA/U.S. DEPARTMENT OF COMMERCE; (INSET) WANG XIAOQIANG
The gloomy appraisal has prompted researchers to redouble efforts to save another endangered Yangtze cetacean, the finless porpoise, known in China as the jiangzhu, or river pig. (Cetaceans include whales, dolphins, and porpoises.) The survey recorded fewer than 300 of the world's only freshwater porpoise (Neophocaena phocaenoides asiaorientalis). Experts now estimate a total population of at most 1400, a 50% decline from the last major survey in 1991. "Without further intervention, the finless porpoise will be the next baiji," says survey member Zhang Xianfeng of the Wuhan Institute of Hydrobiology.
Although biologists knew the baiji was scarce, coming home empty-handed after a 6-week survey up and down the Yangtze was unexpected. A team from China, the United Kingdom, and the United States had planned to follow the survey with a $400,000 "rescue mission" to transfer any captured baiji to Tian-e-Zhou Lake in Hubei Province, a sanctuary holding 30 f inless porpoises. That plan has been shelved, says Pfluger.
The baiji split from other dolphins 20 million years ago. Since then, the baiji's eyes have shrunk to pea size. It can discern only light and dark, so it relies on a finely tuned sonar to hunt prey in the silty Yangtze. The last comprehensive survey in 1997 found 13 baiji; from this figure, experts pegged the population at fewer than 100. "For us to see zero means there might be 10" left in the wild, says survey member Barbara Taylor, a marine biologist with the U.S. National Oceanic and Atmospheric Administration (NOAA). Or, as Pfluger notes, zero may mean zero. If so, the baiji would follow the Stellar's sea cow, Caribbean monk seal, and Japanese sea lion into oblivion as the fourth large marine mammal to go extinct in the last 3 centuries. It would be the first cetacean lost in modern times.
Although the baiji's fate is uncertain, the dangers it faces are all too apparent. The most immediate threat is the use of rolling hooks, says expedition co-director Robert Pitman, a NOAA marine biologist. These illegal fishing lines are stretched across a river and are known to snag and drown baiji. During the survey, says Pitman, "we saw hundreds of fishermen using rolling hooks."
Long-term hazards are pollution and choking boat traffic. Near Poyang Lake in Jiangxi Province, connected to the Yangtze by a narrow channel, Taylor counted some 1200 boats in a span of 2 hours. Between the heavy traffic and numerous factories hard up against the lakeshore, Taylor declares Poyang the "biggest environmental disaster" she's ever seen. That's bad news, as Poyang, China's largest lake, is one of the last redoubts of the finless porpoise: It has the biggest intact population, estimated at 400, with 80 spotted during the survey. Plucking the porpoise from peril won't be simple. Proposed megadams may fragment remaining populations, says Zhang. "There's no hope to change the environmental conditions on the Yangtze," he says. Pfluger says his organization will educate fishers about the impact of illegal fishing and finance a sustainable-fishing initiative at Tian-e-Zhou Lake. There, two or three porpoises are born each year, and captive breeding has resulted in a pregnancy last year, says expedition co-director Wang Ding of the Institute of Hydrobiology. "We have to set up more seminatural reserves like Tian-e-Zhou," Wang says.
Sadly, that approach may no longer be applicable to the baiji, an apparent victim of China's booming economy and the attendant environmental degradation of a mighty river. "It seems the baiji is the only thing that is not made in China anymore," says Pitman.
Jerry Guo is a writer in New Haven, Connecticut.
- 复 白鳍豚绝种了？
家园 水系普遍被污染。 大家不要自欺欺人了。
- 复 水系普遍被污染。
家园 中国七大水系均遭污染, 三成连农业灌溉都不行 你说的完全正确，但是这个白鳍豚绝种事件并不是充分证明。
摘录一段中青报的报道：“2005年，全国人大常委会水污染防治法执法检查组检查发现，中国七大水系中劣五类水体占三成左右，水体已经失去使用功能，成为有害的脏水，连农业灌溉都不行。”
“根据国家环保总局公布的资料，我国的河流、河段已有近1／4因污染而不能满足灌溉用水要求，全国湖泊约有75％的水域受到显著污染。”
现实比报道只差不好，这代表粮食远远没有涨够，粮食商品还可以依赖中国日益扩大的缺口加速上涨。下一个投资概念就是卖水给13亿中国人喝，中国是一个人均淡水量只有世界平均四分一的国家，未来几年投资食水工业将会获利甚丰。
- 复 白鳍豚绝种了？
家园 好象不是这样的吧 前两天在国航航班的杂志上看过相应报道。不是这么说的。据说，五十年未被在野外发现的物种才算是灭绝的。前两年还有人在长江中发现过白鳍豚。而且，这次科考没发现，并不表明长江里没有。说是科考队只考察了部分江段，支流并未考察，而且每天也只考察一段时间，不是24小时监控。
- 复 好象不是这样的吧
家园 前段时间中国国家地理杂志出了一个专题 就是讲长江地区的几种濒危动物，包括白鳍豚、中华鲟、扬子鳄等。白鳍豚一是长期没有在野外发现（前几年死掉的那条琪琪是公的，捉到时已受重伤，几乎救不回来。后来又捉到过两条，一条刚捉到就死了，还有一条是母的，研究人员尝试与琪琪配种没有成功，不久也死了，此后再也没有发现过其它白鳍豚）；二是长江目前的状况已经非常不适合白鳍豚生存。而且一种物种数量少于一定程度（具体多少不记得了）使得现存的这些动物无法使这个物种繁衍下去，就会被视为绝种。
从对人类实用的角度考虑，一种植物绝种带来的影响似乎比一种动物绝种带来的影响大。
家园 你忘了有一条被捉住放养在天鹅洲。 中央电视台在全国征集小名，活动进行一半就死了。
从此就不敢再捉，搞了二十几头江豚在天鹅洲放养，发现江豚没问题，还生了小江豚。
因此基本确定天鹅洲放养白鳍豚也应该没问题，但可能为时已晚。
一种植物绝种带来的影响似乎比一种动物绝种带来的影响大。但植物没有大型动物那么抢眼。
- 复 好象不是这样的吧
家园 最起码说明已经非常非常少了。 豚类不象鱼，只要可视范围内有不大可能不被发现。
- 复 白鳍豚绝种了？
家园 说点捣乱的：物种保护意义何在？ 先戴好钢盔：我知道，我知道，广义上的物种保护意义在于保持生态的多样性，从而使生态平衡更稳定... 但是具体到某个物种上，总感觉是它要灭就让它灭好了... 这个东东是没办法以人的意志为转移的... 比方说棘鳍鱼，大家都以为已经灭绝了 -- 也并没有什么天崩地裂的事情发生么... 后来又发现了两条，好好，大家都高兴了，松了一口气 -- 这么珍贵的物种总算没有完全灭绝 -- 可完全忘记了这之前多少年没有这两条鱼的时候，地球依然地转啊转个不停，春风啊不解风情~~~ 好像跑题了，回来说白鳍豚吧，看了那么多资料，都说是“珍贵的活化石”啊，对研究长江流域古生态变迁有帮助啊什么的... 咱们假设一下，如果早在公元1900年的时候白鳍豚就灭绝了，是不是说这个“长江流域古生态变迁研究”就会遭受灭顶之灾，彻底研究不下去了？
总感觉这个“物种保护”的重要性被人为地夸张了许多... 整体生态环境在不断地恶化，光是声嘶力竭地吆喝对某种特定物种的保护，未免有些视野狭隘了吧...
俺是外行，欢迎科普...
家园 保护濒危野生动物是一个哲学问题，不是经济学问题 其实这跟为什么要研究历史有点类似。搞不通罗马帝国有几个皇帝也不影响现在的人吃麦当劳，炒股票。人类之所以为人类就是要有那么一点责任感和好奇心，因为保护濒危动物得不偿失就不去做，我老觉得这种观念无限发展下去扩展下去是很可怕的。一种动物灭绝就其本身来说不算什么大事，一两个没有竞争优势的物种灭绝了也不会影响人类的生存，但按照这个逻辑，说不定有一天我们会觉得赡养老人也是无用，而通过基因制造优良种族才是正道。
那人就不是人了。
有感而发，不是针对麦帅的，不要误会。
但我也反对那种为了保护而剥夺当地人发展权利的做法，任何人都没有权利要求吃不上饭的农民因为保护金丝猴而不能去砍树。所以，唯一的办法就是把一部分人类的财富转移过来进行保护工作，即使得不偿失或者最终一场空也没有办法，毕竟这是人应尽的义务。
家园 这并不是“做与不做”之问，而是“做多做少”之问 “做与不做”是个态度问题 -- 做是肯定要做的，这个估计大家都没有疑问。
我的问题在于“做多做少” -- 程度之问。保护是肯定要保护的，但问题是这钱要花到什么程度？毕竟作为国家不可能把100%的国民生产总值都投入到保护野生动物上是不是？不可能说宁肯大家饿着肚子也要保护好野生动物是不是？尤其是在目前生态环境整体恶化的大前提下，大力保护某一两种濒危物种，这钱花得值不值？
这是个技术问题，而非态度问题。行走大人这次走了眼了...
家园 嗯，麦帅说得有理。凡事应该有度。 确实不能让大家饿着肚子搞野生动物保护。我大概前段时间刘慈欣的科幻小说看多了，想问题有点走极端。
家园 动物保护归根到底应该是对人的保护。 动物是生态平衡的一部分，生态失去平衡对人也没好处。
对于某种具体动物来说，当前也许不知道它对人类有何用处。但无论如何也是基因库之一，它所拥有的基因将来也许对人有用，而且在生态中是否有关键地位也不易搞清。所以能保护的起码能维持下去将来就不会因缺少这重要一环而造成严重后果。