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How plants reclaimed Chernobyl's poisoned land
切尔诺贝利核灾给大自然带来的意想不到好处
Chernobyl has become a byword for catastrophe. The 1986 nuclear disaster, recently brought back into the public eye by the hugely popular TV show of the same name, caused thousands of cancers, turned a once populous area into a ghost city, and led to an exclusion zone 2,600 sq km (1,000 sq miles) in size.
切尔诺贝利（Chernobyl）已经成为灾难的代名词。这起发生在1986的核灾难导致成千上万民众患癌，曾经人口稠密的地区变成了鬼城，隔离区面积达2600平方公里（1000平方英里）。最近，一部同名电视剧将这起灾难重新带回人们的视野。
But Chernobyl's exclusion zone isn't devoid of life. Wolves, boars and bears have returned to the lush forests surrounding the old nuclear plant in northern Ukraine. And when it comes to vegetation, all but the most vulnerable and exposed plant life survived. Even in the most radioactive areas of the zone, vegetation was recovering within three years.
但切尔诺贝利的隔离区内并不是没有生命。狼、野猪和熊又回到了乌克兰北部老核电站周围茂密的森林里。在植被方面除了最脆弱和暴露在外的植物，大部分都存活了下来。即使是在该地区辐射最强的地方，植被也在三年内恢复了。
Humans and other mammals and birds would have been killed many times over by the radiation that plants in the most contaminated areas received. So why is plant life so resilient to radiation and nuclear disaster?
处在核污染最严重地区的植物，所接受的辐射量足以让人类、其它哺乳动物及鸟类丧命。那么，为什么植物对辐射和核灾难的抵抗力如此之强呢?
To answer this question, we first need to understand how radiation from nuclear reactors affects living cells. Chernobyl's radioactive material is "unstable" because it is constantly firing out high energy particles and waves that smash cellular structures or produce reactive chemicals which attack the cells' machinery.
要回答这个问题，我们首先需要了解核反应堆的辐射会对生物细胞造成什么样的影响。切尔诺贝利的放射性物质是“不稳定的”，因为它在不断地释放高能粒子和波。这些高能粒子和波会破坏细胞结构，或者产生攻击细胞器的活性化学物质。
Most parts of the cell are replaceable if damaged, but DNA is a crucial exception. At higher radiation doses, DNA becomes garbled and cells die quickly. Lower doses can cause subtler damage in the form of mutations altering the way that the cell functions – for example, causing it to become cancerous, multiply uncontrollably, and spread to other parts of the body.
如果受损，细胞中的大部分都是可替换的，但DNA却是个例外。较高剂量的辐射会使DNA变得混乱，导致细胞迅速死亡。低剂量的辐射所造成的损害则更加微妙，会产生基因突变，改变细胞功能。例如，使细胞癌变，无法控制地繁殖，并扩散到身体的其他部位。
In animals this is often fatal, because their cells and systems are highly specialised and inflexible. Think of animal biology as an intricate machine in which each cell and organ has a place and purpose, and all parts must work and cooperate for the individual to survive. A human cannot manage without a brain, heart or lungs.
在动物身上，这通常是致命的，因为动物的细胞和系统高度分化且不容变更。把动物想象成一台复杂的机器，每个细胞和器官都有自己的位置和目的。为了生存，各部门必须协同工作。没有大脑、心脏或肺，人类无法生存。
Plants, however, develop in a much more flexible way. Because they can't move, they have no choice but to adapt to the circumstances in which they find themselves. Rather than having a defined structure as an animal does, plants make it up as they go along. Whether they grow deeper roots or a taller stem depends on the balance of chemical signals from other parts of the plant and nearby plants, as well as light, temperature, water and nutrient conditions.
然而，植物的生长方式要灵活得多。因为无法移动，它们别无选择，只能适应所处的环境。植物不像动物那样有固定的结构，而是在生长过程中逐渐形成的。它们根茎的深度和长度取决于该植物其它部位和附近植物发出的化学信号，以及光照、温度、水分和营养条件。
Critically, unlike animal cells, almost all plant cells have the capacity to create new cells of any type the plant needs. This is why a gardener can grow new plants from cuttings, with roots sprouting from what was once a stem or leaf.
植物细胞区别于动物细胞重要的一点是，几乎所有的植物细胞都有能力产生植物所需要的任何类型的新细胞。这就是为什么园丁可以从插枝中培育出新的植物，从曾经的茎或叶中萌发出根来。
All of this means that plants can replace dead cells or tissues much more easily than animals, whether the damage is due to being attacked by an animal or to radiation.
所有这一切都意味着，植物比动物更容易替换死去的细胞或组织，无论这些损伤的原因是由于动物攻击还是辐射造成。
And while radiation and other types of DNA damage can cause tumours in plants, mutated cells are generally not able to spread from one part of the plant to another as cancers do, thanks to the rigid, interconnecting walls surrounding plant cells. Nor are such tumours fatal in the vast majority of cases, because the plant can find ways to work around the malfunctioning tissue.
虽然辐射和其他类型的DNA损伤可以导致植物体内长出肿瘤，但由于植物细胞周围的细胞壁是刚性的且相互连接，突变细胞通常无法像癌症那样从植物的一个部位扩散到另一个部位。在绝大多数情况下，这样的肿瘤并不致命，因为植物可以找到方法，绕过失灵组织。
Interestingly, in addition to this innate resilience to radiation, some plants in the Chernobyl exclusion zone seem to be using extra mechanisms to protect their DNA, changing its chemistry to make it more resistant to damage, and turning on systems to repair it if this doesn't work. Levels of natural radiation on the Earth's surface were much higher in the distant past when early plants were evolving, so plants in the exclusion zone may be drawing upon adaptations dating back to this time in order to survive.
有趣的是，除了对辐射有天生的抵抗力之外，切尔诺贝利禁区内的一些植物似乎还有额外的机制保护DNA，改变其化学成分，使其能抵抗辐射。如果这不起作用，它们还会启动修复系统。在遥远的过去，早期植物进化的时候，地球表面的自然辐射水平要高得多，所以禁区内的植物为了生存，可能利用了这个时期遗留下来的适应能力。
Life is now thriving around Chernobyl. Populations of many plant and animal species are actually greater than they were before the disaster.
现在，切尔诺贝利周围的生命正在蓬勃发展。许多动植物的数量实际比灾难前还要多。
Given the tragic loss and shortening of human lives associated with Chernobyl, this resurgence of nature may seem surprising. Radiation does have demonstrably harmful effects on plant life, and may shorten the lives of individual plants and animals. But if life-sustaining resources are in abundant enough supply and burdens are not fatal, then life will flourish.
切尔诺贝利事件造成了悲剧性的损失，缩短了人们的寿命，相比之下，大自然的起死回生令人震惊。辐射确实对植物有明显的伤害，并可能缩短个别植物和动物的寿命。但是，如果有充足的资源维持生命，且所受到的影响不是致命的，那么生命终将茁壮成长。
Crucially, the burden brought by radiation at Chernobyl is less severe than the benefits reaped from humans leaving the area. Now essentially one of Europe's largest nature preserves, the ecosystem around the wrecked power plant supports more life than before, even if each individual cycle of that life lasts a little less.
至关重要的一点是，人类离开该地区所带来的好处比切尔诺贝利核电站辐射带来的伤害还要大。现在这一区域成为了欧洲最大的自然保护区之一，受损核电站周围的生态系统比以前更加生机勃勃，即使是动植物的生命周期比以前缩短了一些。
In a way, the Chernobyl disaster reveals the true extent of our environmental impact on the planet. Harmful as it was, the nuclear accident was far less destructive to the local ecosystem than we were. In driving ourselves away from the area, we have created space for nature to return.
在某种程度上，切尔诺贝利之灾揭示了人类对地球环境影响的真实程度。尽管这次核事故造成了损害，但它对当地生态系统的破坏远远小于人类行为造成的破坏。在人类将自己驱逐出这片区域的过程中，为大自然创造了恢复的空间。
