⊙ By Adam Wernick

翻譯：T Boy

AN ANCIENT FOREST BURIED ON THE OCEAN FLOOR

葬身海底的遠(yuǎn)古樹(shù)林

⊙ By Adam Wernick

翻譯：T Boy

海底世界里的“居民”并不都是“原住民”，來(lái)自陸地的“移民”也不少。埋在墨西哥灣水底的一片柏樹(shù)樹(shù)樁就是其中一個(gè)例子，據(jù)說(shuō)，它們已經(jīng)在水下待了五萬(wàn)年以上。這，也許正是人們常說(shuō)的滄海桑田吧……

Host:When we last spoke with Ben Raines of the1)Weeks Bay Foundationin Alabama about a year ago, he told us an amazing story about an underwater woodland off the coast of Alabama. Local fisherman had discovered a mysteriously2)fishy3)patchofocean, and when divers checked it out they found a forest of ancient4)cypress5)stumpson the ocean floor. Since then, Ben has been6)collaboratingwith scientists to study the7)submergedtrees and working on a8)documentaryabout it.

So, Ben, remind us about this forest. What does it look like?

Ben:Well, there’s an ancient river9)channelthat10)meandersthrough the site, and you just see all these11)logs12)layingall over the bottom and then stumps13)projectingup off the bottom. When you get closer and start looking, you know, the logs still have14)bark. We’re actually finding trees with lightning scars on them. They’re just15)incrediblywellpreserved. And it’s just this magic16)sort ofplace you swim through realizing you’re traveling back in time 50,000 years.

Host:Now, you’ve been working with scientists who have been studying this forest over the past year. What have you learned since we last spoke?

Ben:Well, we’ve learned that some of the individual trees may have been as old as 2,000 years before they died, so these were like17)redwoods. We’ve got stumps down there that are up to 10 feet across, and, you know, you don’t see trees like that on the Gulf Coast, and you can’t really imagine them, but before we were here cutting everything down, that’s what was here. Just this forest of trees so big 10 people with their arms18)outstretchedcouldn’t fit all the way around it holding hands.

Host:So, remind me what science tells us about the age of this forest again.

1) Weeks Bay Foundation 威克斯灣基金會(huì)，成立于1990年，是一個(gè)旨在保護(hù)亞拉巴馬海域環(huán)境的非營(yíng)利性組織。

2) fishy [?f???] adj. 可疑的，不對(duì)勁的

3) patch [p?t?] n. 小塊土地，此處指一小塊海域。

4) cypress [?sa?pr?s] n. 柏樹(shù)，柏樹(shù)木

5) stump [st?mp] n. 樹(shù)樁，殘根

6) collaborate [k??l?b?re?t] v. 協(xié)作，合作

7) submerged [s?b?mз?d?d] adj. 沉沒(méi)的，淹沒(méi)的

8) documentary [?d?kj??ment?r?] n. 紀(jì)錄片

9) channel [?t??n(?)l] n. 水溝，水槽

10) meander [m???nd?(r)] v. 蜿蜒而流

11) log [l?ɡ] n. 木頭，原木

12) lay [le?] v. 放，置

13) project [?pr?d?ekt] v. 突出

14) bark [bɑ?k] n. 樹(shù)皮

15) incredibly [?n?kred?b(?)l?] adv. 不可思議的，驚人的

16) sort of 有幾分地

17) redwood [?redw?d] n. 紅杉

18) outstretched [?a?tstret?t] adj. 伸出的，展開(kāi)的

Ben:Well, you know, if you look just at the depth, you would think that it should be about 12-14,000 years old. But then, when we did the actual radiocarbon dating, which was done at the Lawrence Livermore National Laboratory, they did it three times,’cause they were so puzzled they came backradiocarbon dead, which means older than 50,000 years. So, what they believe has happened is, as Louisiana has gotten heavier over the19)eonswith mud coming down the Mississippi River,20)weighing downthe delta over there, it’s caused the bottom over here to rise up like a21)bulge. Like, if you squeeze a balloon, it gets bigger in another spot.

So, the depth here doesn’t appear to be accurate as far as how old the forest is. So, now we’re having some uranium dating done of the trees, and that’s gonna be done in Taiwan, and it’s a whole new technique, so hopefully we’ll get a very accurate date for when the forest was dry land.

Host:But at this point it’s something more than 50,000 years.

Ben:Right, and that’s about as precise as we can get right now.

Host:What’s the latest theory as to how this forest got there? What was the accident in nature that preserved this whole thing?

Ben:Well, we’re still working on that a little bit, and when we get a more precise date we may be able to tie it to some sort of event like a22)meteoror something like that. The other possibility is a big hurricane. You know, sea levels were coming up and it may have just23)shifted24)sedimentsenough to bury this stuff. And so, once things get covered up, they get protected from oxygen, there’s no25)decay. So these trees were essentially26)entombed, you know, while they were living. And that’s why all the trees look like they were cut off at the same height. When you cut into them with a27)saw, they still smell fresh, like fresh28)pineytrees, and they have29)sapthat30)oozesout of the cuts.

19) eon [?i??n] n. 無(wú)限長(zhǎng)的時(shí)代，永世

20) weigh down 使負(fù)重，使下沉

21) bulge [b?ld?] n. 凸出，鼓起

22) meteor [?mi?t??(r)] n. [天]流星，隕石

23) shift [??ft] v. 變換位置，移動(dòng)

24) sediment [?sed?m?nt] n. 沉積物，沖積物

25) decay [d??ke?] n. 腐爛

26) entomb [?n?tu?m] v. 埋葬

27) saw [s??] n. 鋸

28) piney [?pa?n?] adj. 似松的，松樹(shù)般茂盛的

29) sap [s?p] n. 樹(shù)液

30) ooze [u?z] v. 滲出，分泌出

◆ Gulf Coast 墨西哥灣海岸：美國(guó)以南的墨西哥灣（Gulf of Mexico）海岸。墨西哥灣是北美洲大陸東南沿海水域，大部分為美國(guó)和墨西哥環(huán)抱，通過(guò)美國(guó)的佛羅里達(dá)半島和古巴島之間的佛羅里達(dá)海峽與大西洋相連，并與加勒比海相通。密西西比河在此注入大西洋。在美國(guó)英語(yǔ)中，Gulf Coast即指美國(guó)南部與墨西哥灣相接的海岸，Gulf States則指得克薩斯州、路易斯安那州、密西西比州、亞拉巴馬州和佛羅里達(dá)州。

◆ Radiocarbon Dating 放射性碳素?cái)啻ǎ河址Q(chēng)碳-14年代測(cè)定法，是測(cè)定古代遺存年代的一種方法。有放射性的碳-14同位素在有機(jī)物所含碳素中占有一定比例，死亡后大約每隔5730±40年減少一半。因此，根據(jù)古代遺留下來(lái)的有機(jī)物中碳-14放射性的減少程度，便可以測(cè)知其死亡年代?，F(xiàn)在該技術(shù)可測(cè)定約五萬(wàn)年以?xún)?nèi)的年代。

◆ Uranium Dating 鈾系法測(cè)年法：同位素地質(zhì)測(cè)定年代的方法之一，根據(jù)鈾系核素的放射性比值來(lái)測(cè)定沉積物的地質(zhì)年代。同位素238U和235U所產(chǎn)生的衰變系列中含有多種放射性同位素，在正常的地質(zhì)過(guò)程中，這些鈾的子體從母體中分離，按其各自的半衰期所決定的速率進(jìn)行衰變，母體則衰變形成子體核素。利用輻射探測(cè)器可測(cè)定核素的放射性比值，以此推算出沉積物的年齡。

◆ Mississippi River 密西西比河：位于北美洲中南部，是美國(guó)最大的河流，也是北美洲流程最長(zhǎng)、流域面積最廣、水量最大的河流。全長(zhǎng)約3730公里，僅次于非洲的尼羅河、南美洲的亞馬孫河和中國(guó)的長(zhǎng)江，居世界河流的第四位。密西西比河干流流經(jīng)美國(guó)的10個(gè)州：明尼蘇達(dá)州、威斯康星州、艾奧瓦州、伊利諾伊州、密蘇里州、肯塔基州、田納西州、阿肯色州、密西西比州、路易斯安那州。整個(gè)水系流經(jīng)美國(guó)本土48州中的31個(gè)州，以及加拿大的兩個(gè)州。

主持人：大約在一年前，我們?cè)谶@個(gè)節(jié)目與本·雷恩斯交談——他為位于美國(guó)亞拉巴馬州的威克斯灣基金會(huì)工作。當(dāng)時(shí)，他給我們講述了一片離亞拉巴馬州海岸不遠(yuǎn)處的水下樹(shù)林的神奇故事。當(dāng)?shù)貪O民在海中發(fā)現(xiàn)了一片神秘莫測(cè)、讓人心生疑惑的海域。潛水員下去探個(gè)究竟，發(fā)現(xiàn)在海底有一片遠(yuǎn)古柏樹(shù)樹(shù)樁。從那以后，本就一直與科學(xué)家一起研究這片被海水淹沒(méi)的樹(shù)林，并致力于制作一部關(guān)于這片樹(shù)林的紀(jì)錄片。

本，跟我們重溫一下這片海底樹(shù)林的情況。它長(zhǎng)什么樣？

本：嗯，有一條古河道從這個(gè)地方蜿蜒而過(guò)，你可以看到這些原木散落在海底，海底還杵著一根根柏樹(shù)樹(shù)樁。如果你接近這些原木仔細(xì)去看，你知道，你會(huì)發(fā)現(xiàn)這些原木還有樹(shù)皮。事實(shí)上，我們發(fā)現(xiàn)這些樹(shù)上有曾被閃電打中留下的傷痕。它們真的保存得非常好。你如果在這個(gè)地方游過(guò)，意識(shí)到自己正穿越到五萬(wàn)年前，眼前的景象幾乎成了一個(gè)魔幻之地。主持人：好，在過(guò)去的一年里，你一直在與研究這片海底樹(shù)林的科學(xué)家并肩工作。自從我們上次交談后，你又了解到些什么新情況？

本：嗯，我們了解到有些樹(shù)在死去之前可能已經(jīng)有兩千年樹(shù)齡了，像紅杉那么老。水下有些樹(shù)樁的直徑達(dá)10英尺（約3.05米），要知道，如今你在墨西哥灣沿岸地區(qū)可看不到這樣的大樹(shù)，因此也無(wú)從想象。但在人類(lèi)把這個(gè)區(qū)域所有樹(shù)木都砍光之前，這個(gè)地區(qū)的樹(shù)就長(zhǎng)這樣。這片樹(shù)林里的樹(shù)非常粗壯，就算十個(gè)人伸開(kāi)雙臂，手拉手也抱不過(guò)來(lái)。

主持人：好吧，請(qǐng)?jiān)俑嬖V我們，科學(xué)家說(shuō)這片樹(shù)林到底有多古老呢？

本：呃，你知道嗎，如果你只考慮它在水下的深度，你會(huì)以為它們可能有大約一萬(wàn)兩千年到一萬(wàn)四千年的歷史?？墒呛髞?lái)我們?cè)趧趥愃埂だツ獱柸珖?guó)實(shí)驗(yàn)室用放射性碳定年法測(cè)定樹(shù)林的年代。他們做了三次，因?yàn)橛梅派湫蕴级攴ǖ貌坏浇Y(jié)果，這讓他們很困惑，這也意味著這些樹(shù)有五萬(wàn)年以上的歷史。如此一來(lái)，他們認(rèn)為真相是這樣的：經(jīng)過(guò)非常非常漫長(zhǎng)的歲月，密西西比河攜帶著泥沙往下游流去，導(dǎo)致路易斯安那州日漸變得不堪重負(fù)，重重地壓著那里的三角洲，以至于這里的底部鼓起了一塊。就像一個(gè)氣球，你擠壓這個(gè)地方，就會(huì)在另一個(gè)地方鼓起一團(tuán)。

所以在這種情況下，樹(shù)樁在水下的深度就無(wú)法準(zhǔn)確判斷樹(shù)林的年齡。因此，我們現(xiàn)在將通過(guò)鈾系法對(duì)樹(shù)樁進(jìn)行年代測(cè)定，檢測(cè)會(huì)在臺(tái)灣進(jìn)行。這是一項(xiàng)全新的技術(shù)，我們希望借此準(zhǔn)確地知道這片樹(shù)林還處于干燥的土地上時(shí)到底有多老。

主持人：可就目前的研究成果而言，這片樹(shù)林超過(guò)五萬(wàn)歲了。

本：對(duì)，這是如今我們能夠確定的、最準(zhǔn)確的年代了。

主持人：關(guān)于這片樹(shù)林如何跑到海底的最新解釋是什么？究竟是自然界的什么偶發(fā)事件把整片樹(shù)林保存得如此完好呢？

本：這個(gè)嘛，我們還在研究當(dāng)中。等我們知道了這片樹(shù)林的準(zhǔn)確年代，也許就可以把它與一些諸如隕石墜落之類(lèi)的事件聯(lián)系起來(lái)。另一個(gè)可能就是颶風(fēng)。你知道，海平面上升，有可能導(dǎo)致水中的沉積物大規(guī)模移動(dòng)，使這片樹(shù)林葬身海底。這樣一來(lái)，一旦樹(shù)林被完全覆蓋，它們就被保護(hù)了起來(lái)，接觸不到氧氣，就不會(huì)腐爛。所以說(shuō)這些樹(shù)實(shí)際上是在活著的時(shí)候就被埋在下面了，你知道吧。這就是為什么所有的樹(shù)看起來(lái)好像在同一個(gè)高度被砍倒。就好像你用鋸去鋸這些樹(shù)，樹(shù)還會(huì)散發(fā)出新鮮的氣味，是那種新鮮的松樹(shù)氣味，還有樹(shù)液從斷口滲出呢。