你對樹木所不瞭解的另一面(下)

tate Limbs

5.斷枝的植物們

Trees cannot heal a physical wound like a human does. In order to remain healthy and alive, a tree needs to be energy-efficient, and recovery is just an unaffordable drain on resources. Instead of applying a Band-Aid and mustering up some healing, the plant blocks off all life to the injured part, effectively abandoning it. The benefits of this are twofold. Not only does this shut the door solidly in the face of nasties that could further infect the entire tree, but it can now spend its valuable energy on new growth somewhere else.

樹木在受傷以後並沒有類似於我們人類的免疫自愈能力。所以爲了圖謀生存，他們除了增強自身免疫別無選擇。取而代之，與貼個繃帶癒合傷口不一樣，植物一旦出現傷口，會自動放棄拯救。這給它們帶來的好處是雙倍的，一方面，它可以防止外界塵埃的進入，進而制止其破壞整個植物結構；另一方面，這樣有利於將有價值的能量轉移到新生長的地方。

However, amputation is not a fail-safe survival switch. Sometimes, a wound is just too large or infected, and sickness and rot eventually kill off the tree. But when it does work, the damaged cells start the process through leaking their contents which then oxidize and form the lifesaving barrier. As time passes, the wound will eventually close up as every year's new growth forms around it.

然而，植物截肢並不是一種從死亡向倖存的過渡。有時候，傷口過大容易引起感染，病毒不斷侵入，直至植物喪命。而當真正奏效之時，被破壞的細胞組織耗散那些即將氧化的成分，形成保護生命的物質。隨着時間的流逝，傷口會最終癒合，植物又會迎來新一年的生長。

Have Audible Angst

4.可聽見的"焦慮"

French scientists have recorded a sound trees make when they undergo drought stress. They don't ask for a cup of tea in a parched voice—oh, no—trees get weird. They bubble. But by the time they're bloop-blooping somewhere in the ultrasonic range, a dangerous process is already occurring that can prove fatal to the unlucky bubbler.

法國科學家在樹木遭受乾旱的時候記錄下了它們發出的聲音。我指的可不是它們因爲天氣炎熱而想要通過發出嘶啞的聲音得到杯茶，這樣的樹會嚇死人的。它們只是在風的作用下隨意發出一些不規則的聲音。但是，正是在它們發出那些在超聲波範圍內的噪音時，一些危險且致命的事情也在同時發生在這些不幸的小傢伙身上。

To get water to all of their extremities, trees suck the lifesaving liquid—under the pressure of several atmospheres—through special tubes called xylem. During a drought, the plant must increase this pressure but, in doing so, air bubbles form that can interfere with the water flow, and these are the stress sounds now audible to the right microphone. Scientists call the phenomena "cavitations" and, since too many cavitations can kill trees—sometimes endangering valuable plantations—it's crucial to know when they start. The French scientists are aiming to eventually create a device that can capture this ultrasonic noise in order to alert forest managers when a tree needs an emergency watering or even automatically activate a watering device.

在許多極端環境下，爲了盡它們最大的努力得到水，樹木通過叫做木質部（xylem）的特殊導管汲取維持生命的水分。尤其在旱季期間，植物汲取水分的壓力更加大，但是，與此同時，空氣也產生阻礙水流通的氣泡。正是這些相互影響的氣流壓力使得我們能通過麥克風聽到樹的"焦慮"。科學家把這種現象稱爲"氣穴現象"（Cavitation）。因爲經歷太多"氣穴現象"對許多珍貴植物有害，所以知道這種現象發生前的時間非常重要。法國科學家正致力於發明一種能夠捕捉到這個超聲波噪音的裝置，並將其用於敦促森林管理員在樹木缺水的時候給予緊急補水。他們更想要的是這種裝置能夠在樹木需要時自動啓動補水功能。

cular Memory

3.分子記憶

During a study of genetically identical poplar trees, researchers found that the specimens responded to their present environment based on what individuals had gone through in the past, pointing to some sort of memory at a molecular level. Researchers took stem cuttings from poplars and, apart from the fact that the cuttings came from two different nurseries, everything else about the experiment that followed was identical. The genes of the cuttings, species, and environment in which they were raised were all the same to allow researchers to notice any difference in reaction. And they got it.

在一項對基因相同的楊樹的研究當中，研究者發現這些樣本對當下環境的反應跟它們過去遭受過的環境有很大關係，這在一定程度上證明了楊樹具有分子記憶。研究者從這些楊樹中抽取枝幹作爲樣本，除了來自兩個不同的培養區，來到實驗室後它們所有的實驗因素都是相同的。樣本的基因、種類以及培養環境都是一樣的，以便於研究者及時發現區別。他們得到了結果。

Simulating drought for some while watering the rest, the scientists expected the poplars to all react the same since they were in effect genetic clones. But the trees from Alberta activated a different group of genes in response to the "drought" than the poplars obtained from Saskatchewan. This pointed to the plants "remembering" where they came from.

通過在實驗室內模擬乾燥和溼潤兩種環境情況，研究者期望這些楊樹產生的反應都是一樣的，因爲它們屬於同一個基因羣。但是，取自於亞伯達（Alberta）的柳樹枝因對過去幹燥環境的"記憶"產生了一組與取自於薩斯喀徹溫省（Saskatchewan）的不同的基因。這就很好地證明了植物能夠"記得"它們是從哪來的。

uage Of Leaves

2.樹葉的語言

Perhaps "leaves" is the wrong word here. Trees do not use sign language with their foliage to greet each other in the morning—that would just freak everybody out. Communication between trees happens subtly and below ground. Suzanne Simard, a forest ecologist, has made the unprecedented discovery that forest trees communicate and share resources with each other via their roots. With the help of symbiotic fungi, trees can actually feed seedlings with the nutrients the youngsters need to survive.

或許"樹葉"在這裏是錯誤的詞語。在早晨，樹不會用手語對它們的葉子打招呼，那隻會使葉子極度興奮。樹木之間的交流在地下隱隱約約地發生。一位名叫蘇珊娜·西瑪德（Suzanne Simard）的森林生態學家做出了新奇的發現，那就是森林裏的樹木通過它們的根互相交流和分享資源。事實上，在共生真菌的幫助下，樹木可以向幼苗提供"年輕人"賴以存活的營養。

This fungal network also allows bigger trees the opportunity to swap necessities like water and carbon with other trees, depending on their needs. Simard also identified the phenomenon of "mother trees"—the really old and massive trees in a forest. Not only are mother trees connected to all the other trees, but they seem to be the heartbeat of the woodland. They control and dispense resources through the massive fungal web and, when such a matriarch is chopped down, younger trees face a reduced survival rate.

取決於樹木的需要，這種由真菌引起的網絡關聯也允許更大的樹和其它樹交換水和碳這樣的必需品的機會。西瑪德也發現了一種在森林裏又年老又壯大的"母親樹"的現象。母親樹不僅與其它樹相聯繫，它們似乎還是森林的脈搏。它們通過龐大的真菌聯繫網控制和分配資源，當這樣的女統治者被砍掉，幼樹的存活率降低。

n As A Competitive Edge

1.作爲競爭優勢的縱火

Wryly nicknamed "gasoline trees," the popular eucalyptus tree is almost designed to prepare the groundwork for a devastating bush fire. Their broad ribbons of dry, peeling bark create tinder all over the place, made even more dangerous by the extremely flammable oil it produces.

受歡迎的桉樹被嘲諷地稱爲"汽油樹"，它幾乎是爲了準備毀滅性的叢林大火而設計的。它們那寬闊乾燥的帶狀物脫落樹皮爲各地創造火種，這使得極度易燃的精油生產甚至變得更加危險。

This combination is what makes this tree the firefighter's archenemy because it can turn a manageable ground fire into an uncontrollable firestorm in minutes. In 1991, over 3,000 homes and 25 lives were lost after eucalyptus trees caught fire throughout the Oakland Hills of California. After such sweeping wildfires, eucalyptus babies thrive without a problem. During their first couple of years, the young trees will grow intensively, sometimes at the cost of other species that can't keep up. Despite their arsonist nature, eucalyptus trees remain coveted for their strange beauty, fast growth, and prized essential oil.

這種組合的樹成爲消防員的大敵，因爲它可以把一個可控制的地面火力在數分鐘內轉變爲無法控制的風暴火。1991年，在桉樹起火席捲加利福尼亞奧克蘭山之後，超過3000個家庭和25條人命沒有了。在發生這樣徹底的野火後，對桉樹"嬰兒們"的茁壯成長沒有影響。在它們最初的幾年中，年輕的樹集中生長，有時以其它物種跟不上生長的步伐爲代價。儘管它們有縱火犯的本質，桉樹因其獨特的美，生長快速和珍貴的精油仍然被人覬覦。

翻譯:哈利小王子 來源:前十網