There is only one planet in the universe,as far as we know, 据我们所知,宇宙中只有一颗行星,
where there is life. 哪里有生命.
The Earth. 地球.
Our home. 我们的家.
The perfect planet. 完美的星球.
Life here is only possible 这里的生活是唯一可能的
because of a unique balance of natural forces. 因为自然力的独特平衡.
Energy from the sun powers the living world. 来自太阳的能量为生活世界提供能量.
Weather systems transport fresh water around the globe. 天气系统将淡水输送到全球各地.
And powerful ocean currents 强大的洋流
circulate life's essential nutrients. 循环生命的基本营养.
This series will reveal how these global forces have worked together 本系列将揭示这些全球力量是如何协同工作的
to create our planet's fragile life-support system. 创造我们星球脆弱的生命维持系统.
One of these forces is so important 其中一种力量非常重要
that life would never have even started without it. 如果没有它,生活就不会开始.
Across the surface of our planet, 穿过地球表面,
there are over 1,500 active volcanoes. 有1500多座活火山.
This is the most active - Kilauea in Hawaii. 这是夏威夷最活跃的基拉韦厄.
Here,magma - liquid rock from the planet's hot interior - 在这里,岩浆-液态岩石来自行星炽热的内部-
bursts out through fractures in the Earth's crust, 从地壳的裂缝中爆发出来,
and it's been flowing for months. 已经流了好几个月了.
Nothing can stand in the lava's way. 没有什么能阻挡熔岩.
Volcanoes are certainly destructive. 火山当然具有破坏性.
But without these powerful underground forces, 但是没有这些强大的地下力量,
there would be no breathable atmosphere. 没有可呼吸的空气.
No oceans. 没有海洋.
No land. 没有土地.
No life. 没有生命.
We can't control volcanoes, 我们无法控制火山,
but they're vital for all living things on Planet Earth. 但它们对地球上所有生物都至关重要.
This is Ol Doinyo Lengai in Tanzania. 我是坦桑尼亚的Ol Doinyo Lengai.
It's one of Africa's most active volcanoes, 它是非洲最活跃的火山之一,
and has erupted over 15 times in the last 100 years. 在过去的100年里已经爆发了15次.
On its northern flank lies Lake Natron, 它的北侧是纳特龙湖,
400 square miles in extent, 面积400平方英里,
and one of the world's most corrosive bodies of water. 世界上最具腐蚀性的水体之一.
The water wells up from deep below, 从地下深处涌出的水井,
carrying such a concentration of chemicals that it can burn skin. 携带如此浓度的化学物质会灼伤皮肤.
But one animal thrives here. 但有一种动物在这里繁衍生息.
Volcano birds. 火山鸟.
Nearly two million lesser flamingos live in East Africa 近200万只小火烈鸟生活在东非
and all of them come here to breed. 它们都来这里繁殖.
But they can only nest here when the lake's level 但它们只能在湖水平的时候在这里筑巢
drops so far that in the centre,its bed is exposed. 下降到如此之远,以至于在中心,它的床是暴露的.
And that rare moment is now. 那难得的时刻就是现在.
How they know when the conditions are right is a mystery, 他们怎么知道什么时候条件合适是个谜,
but some have flown thousands of miles to be here. 但有些人已经飞了几千英里来到这里.
The flamingos head for the middle of the lake, 火烈鸟向湖中央飞去,
where the intense evaporation has created islands of salt. 剧烈的蒸发形成了盐岛.
It's here that the birds build their nests, 鸟儿在这里筑巢,
over three miles from the lake's edge 离湖边三英里多
and safe from land predators,which are unable to cross 远离无法穿越的陆地掠食者
the surrounding moat of caustic soda. 周围的苛性钠护城河.
The single egg is laid on a mount of hardened salt 一个蛋产在一堆坚硬的盐上
built by the adults, 由成年人建造,
its height an insurance against a sudden rise in water level 它的高度是防止水位突然上升的保险
which often happens on Lake Natron. 这经常发生在纳特龙湖.
As the centre dries and enlarges, 随着中心变干变大,
more and more flamingos arrive to nest on it. 越来越多的火烈鸟来到这里筑巢.
In good years,such as now, 在好年头,比如现在,
as many as half a million pairs breed here. 多达50万对在这里繁殖.
After 28 days of incubation, 孵育28天后,
a chick emerges into Natron's harsh glare. 一只小鸡出现在纳特龙刺眼的目光中.
Here,temperatures can rise to 55 degrees Celsius. 在这里,温度可以上升到55摄氏度.
Mother's wing,however,can serve as a sun shield. 然而,母亲的翅膀可以起到防晒的作用.
The chick is fed a rich liquid 小鸡被喂了大量的液体
made of the lake's barely digested algae 由湖中几乎不能消化的藻类组成
and traces of its parent's blood. 还有它父母的血迹.
After a few days,the chick is strong enough to stretch its legs. 几天后,小鸡就强壮到可以伸展腿了.
It then joins a growing creche,made up of chicks of different ages. 然后它加入了一个成长中的托儿所,由不同年龄的小鸡组成.
Soon,the need for fresh water will force the infant birds 很快,对淡水的需求将迫使幼鸟
to trek to springs on the lake's edge. 长途跋涉到湖边的泉水.
A journey they have to make on foot, 他们必须徒步旅行,
as their flight feathers have yet to develop. 因为它们的飞行羽毛还没有发育.
Every day,the adults fly to these springs to feed. 每天,成虫都飞到这些泉水里去觅食.
Here,on the lake's margins,they collect algae that flourish 在这里,在湖边,他们收集藻类繁盛
in the volcanic water - 在火山水中-
vital food for the flamingos. 火烈鸟的重要食物.
It's the algae that turn the flamingos' feathers pink. 是藻类使火烈鸟的羽毛变成粉红色.
It even colours their eyes. 甚至给他们的眼睛涂上颜色.
The adults spend most of their day at the springs, 成年人一天的大部分时间都呆在泉水里,
and now their chicks are going to join them there. 现在他们的小鸡要加入他们的行列了.
No-one wants to get left behind. 没有人想被落在后面.
It's a three-mile march over razor-sharp flakes of soda 在锋利的苏打水上行进了三英里
and sticky,caustic mud. 还有粘稠的腐蚀性泥浆.
A life-threatening trial,especially for the youngest chicks. 危及生命的审判,尤指对幼雏的审判.
The groups merge into one giant creche. 这些团体合并成一个巨大的托儿所.
For some,the challenges are just too great. 对一些人来说,挑战太大了.
Exhaustion overcomes the weakest. 精疲力竭战胜最虚弱的人.
And now,there is yet another threat. 现在,还有另一个威胁.
Marabou storks. 马拉布鹳.
They have long legs like a flamingo, 它们的腿长得像火烈鸟,
but a beak like a Roman sword. 而是一把像罗马剑一样的喙.
And they are patient, 他们很有耐心,
waiting for an easy target. 等待一个容易的目标.
Their very presence creates panic among the chicks. 它们的出现引起了小鸡们的恐慌.
The smallest avoid being trampled underfoot 最小的避免被踩在脚下
by travelling on the outside of the group. 在团队之外旅行.
But that exposes them to attack. 但这会让他们受到攻击.
Their only defence is to run. 他们唯一的防御就是逃跑.
But you have little chance 但你几乎没有机会
when you're barely ankle-high to your pursuer. 当你和你的追求者只有脚踝高的时候.
Stragglers will almost certainly be taken. 掉队者几乎肯定会被带走.
But there comes a point when every stork has had its fill. 但总有一天,每只鹳都会吃饱的.
This little chick is very lucky. 这只小鸡很幸运.
At last,the youngsters reach the freshwater springs 最后,孩子们到达了淡水泉
at the lake's margin to rejoin their parents. 在湖边与父母团聚.
Almost unbelievably,each chick has a unique call 几乎难以置信的是,每个小鸡都有一个独特的叫声
that its parent can recognise. 它的父母能认出.
It's not just lesser flamingos that depend on volcanoes. 不仅仅是较小的火烈鸟依赖火山.
Ultimately,so do all living things. 最终,所有生物也是如此.
Over 80% of the Earth's surface 地球表面的80%以上
is the result of magma bursting up from the molten interior. 是岩浆从熔融的内部喷出的结果.
The process started four billion years ago 这个过程始于40亿年前
and it still continues today. 今天仍在继续.
When lava cools,it solidifies into rock, 当熔岩冷却时,会凝固成岩石,
and eventually weathers into land that can support life. 最终风化成能维持生命的陆地.
All the Galapagos Islands in the Pacific are volcanic, 太平洋上所有的加拉帕戈斯群岛都是火山,
and Fernandina is the youngest of them. 费尔南迪娜是其中最小的.
And still growing. 而且还在增长.
At its centre,a volcanic crater four miles wide 在它的中心,一个四英里宽的火山口
and over 800 metres deep. 深度超过800米.
It seems dormant,but it was erupting only two weeks ago. 它似乎处于休眠状态,但两周前才喷发.
Even so,there are some who depend on the heat from this volcano. 即便如此,仍有一些人依赖这座火山的热量.
A female land iguana,heavy with eggs,approaches the crater's rim. 一只雌性陆地鬣蜥,带着厚厚的卵,靠近陨石坑的边缘.
It took her ten days to climb up here, 她花了十天时间爬到这里,
but the toughest part of her journey is still ahead. 但她最艰难的旅程还在前方.
She's going to descend into the crater itself. 她会自己掉到陨石坑里.
Frequent tremors make the crater walls unstable. 频繁的震动使火山口壁不稳定.
More people have travelled in space 更多的人在太空旅行
than have visited the bottom of Fernandina's crater. 而不是参观费尔南迪娜火山口的底部.
But instinct drives her on. 但本能驱使她继续前进.
The warm volcanic ash on the crater floor 火山口底部温暖的火山灰
has the perfect temperature for incubating her eggs. 有完美的温度孵卵.
But there are no clear paths down. 但是没有明确的路径.
Any made last year have been destroyed by rock falls. 去年制造的任何东西都被落石摧毁了.
The slope is steep and unstable. 这个斜坡很陡,不稳定.
Tumbling rocks quickly become an avalanche. 翻滚的岩石很快就变成了雪崩.
With the boulders falling down away from her, 随着巨石从她身边落下,
she's not in immediate danger. 她现在没有危险.
But behind her,higher up, 但在她身后,更高的地方,
two other females have also started the descent. 另外两名女性也开始下降.
And now she is in the firing line. 现在她在射击线上.
She's safe. 她很安全.
Others before her haven't been so lucky. 在她之前的其他人可没这么幸运.
But she's undeterred. 但她没有被吓倒.
At last,after an eight-hour descent, 最后,经过8个小时的下降,
she reaches the crater floor. 她到达火山口底部.
Now she must find a suitable place to dig her nest. 现在她必须找一个合适的地方挖她的窝.
The best sites are already taken. 最好的地点已经被占领了.
And nesting females are very aggressive. 筑巢的雌性非常好斗.
A nodding head means keep away. 点头表示远离.
Push off! 走开！
Ignored warnings are met with force. 被忽略的警告将被强制执行.
But she's come a long way,and she's not going to give up now. 但她已经走了很长的路,她现在不会放弃.
She,too,starts to dig a hole in which to lay her eggs. 她也开始挖洞产卵.
That done,she will head back, 做完了,她会回去的,
leaving the volcano to provide the warmth her eggs need 离开火山为她的蛋提供所需的温暖
if they are to hatch. 如果它们要孵化的话.
Sometimes,of course,the volcano erupts 当然,有时火山会喷发
and destroys not only eggs but many nesting adults. 不仅破坏卵子,也破坏许多筑巢的成虫.
But for the iguanas, 但对于鬣蜥来说,
the benefits of nesting in the crater are so great 在火山口筑巢的好处是如此巨大
that it's worth all the risks. 它值得所有的风险.
Volcanic islands make up just 5% of the planet's land, 火山岛只占地球陆地的5%,
but they're home to nearly 20% of its species. 但它们是近20%物种的家园.
Animals often evolve very swiftly on islands, 动物在岛屿上的进化通常非常迅速,
cut off from their mainland relatives 与大陆亲戚断绝联系
and faced with the challenges of isolation. 面对与世隔绝的挑战.
This is Wolf,an extinct volcano 这是狼,一座死火山
and one of the most remote islands of the Galapagos, 加拉帕戈斯最偏远的岛屿之一,
800 miles from the nearest large landmass 离最近的大陆地800英里
and over a million years old. 超过一百万年了.
A finch. 一只雀.
A female. 女性.
Its ancestors doubtless were blown here by storms many centuries ago. 毫无疑问,它的祖先在许多世纪前就被风暴吹到了这里.
Like most finches,they feed on seeds,nectar and insects. 像大多数雀类一样,它们以种子、花蜜和昆虫为食.
But there's little food of any kind on Wolf. 但是狼身上几乎没有任何食物.
And since they aren't strong enough fliers to leave the island, 因为他们没有足够的力量离开这个岛,
they've had to find food from a very unusual source. 他们不得不从一个非常不寻常的地方寻找食物.
They depend on another of the island's inhabitants. 他们依靠岛上另一个居民生活.
Nazca boobies. 纳斯卡的胸部.
Every day,these sea birds commute 这些海鸟每天通勤
between the island and their fishing grounds out in the open ocean. 在岛和他们的渔场之间.
Each time a pair meet,they renew their bond. 每一次一对相遇,他们就会重新建立联系.
And then catch up with the neighbours. 然后赶上邻居.
Now is the time 现在是时候了
to hop into action. 开始行动.
Blood. 血.
They are vampire finches. 它们是吸血鬼雀.
These little birds have become one of the world's newest species. 这些小鸟已经成为世界上最新的物种之一.
She cuts the quill of a large flight feather, 她剪下一根大羽毛的羽毛,
and the blood flows. 血液流动.
The sight of it attracts the attention of others. 一看到它就会引起别人的注意.
Blood is very nutritious - worth fighting for. 血液很有营养,值得为之奋斗.
So with this never-ending supply of food, 所以有了源源不断的食物,
the vampire finches can flourish on an island 吸血鬼雀可以在岛上繁衍生息
where otherwise they could not survive. 否则他们就活不下去了.
Why the boobies don't object,nobody knows. 没人知道为什么胸部不反对.
Perhaps the finches' behaviour started 也许是雀鸟的行为开始了
when they helped the boobies to remove parasites from their plumage. 当他们帮助胸部去除羽毛上的寄生虫时.
Maybe the boobies think that the little vampires 也许胸部认为小吸血鬼
are still providing a service. 仍在提供服务.
Who can tell? 谁知道呢？
Volcanic islands don't last forever. 火山岛不会永远存在.
Changes deep in the Earth's crust bring their eruptions to an end 地壳深处的变化结束了它们的喷发
and the forces of erosion then begin to wear them down. 侵蚀的力量开始把它们磨损.
But the coral around them continues to grow, 但周围的珊瑚还在继续生长,
sea levels change,and eventually all that is left 海平面变化,最终剩下的一切
is a ring-shaped island of coral rock surrounding a lagoon. 是环礁湖周围珊瑚岩形成的环形岛屿.
An atoll. 环礁.
There are hundreds of atolls in tropical seas, 热带海域有数百个环礁,
all remnants of vanished volcanoes. 所有消失的火山遗迹.
This is one of the largest and most pristine - 这是一个最大的和最原始的-
Aldabra,in the Indian Ocean. 阿尔达布拉,在印度洋.
20 million years ago,it was an island 两千万年前,它还是一个小岛
with a volcanic crater in its centre. 中心有一个火山口.
Now,it's an atoll. 现在,它是一个环礁.
Mangroves took root and sea birds came to nest. 红树林扎根,海鸟来筑巢.
One land animal in particular 特别是一种陆地动物
reached here before man. 在人类之前到达这里.
A giant tortoise. 一只巨大的乌龟.
These creatures can float 这些生物可以漂浮
and live without food or fresh water for long periods of time. 长期没有食物和淡水.
This isolated atoll is the perfect refuge. 这个孤立的环礁是完美的避难所.
Their only enemy is the sun. 他们唯一的敌人是太阳.
Without shade,a tortoise risks being boiled in his shell. 没有阴凉处,乌龟有被壳煮的危险.
So,after feeding in the cool of the morning, 所以,在凉爽的早晨进食后,
and before the sun becomes too crushingly hot, 在太阳变得太热之前,
they have to find cover. 他们必须找到掩护.
All of them. 所有的.
There is very little vegetation,but caves in the coral rock 植被很少,但珊瑚岩中有洞穴
can provide the shade they so badly need. 能提供他们急需的荫凉.
He's nearly there. 他快到了.
All that is left is a white-knuckle ride to the bottom. 剩下的只是一次白费力气的冒险.
And he's in. 他在里面.
Thousands of others are still out in the sun. 成千上万的人仍在阳光下.
This tree could shade a couple of hundred,if they pack tight. 这棵树可以遮住几百棵,如果他们挤得紧的话.
It's bumper-to-bumper parking. 这是一辆接一辆的停车场.
Within an hour or so,all must find shade of some sort 在一个小时左右的时间里,所有人都必须找到某种阴影
if they're to survive. 如果他们想活下来.
Safe. 安全.
But the future for Aldabra's tortoises is far from certain. 但是阿尔达布拉乌龟的未来还很不确定.
The climate is changing,sea levels are rising, 气候在变化,海平面在上升,
and Aldabra's tortoises may soon have to find a new refuge, 阿尔达布拉的乌龟可能很快就会找到新的避难所,
or drown. 或者淹死.
In some places,volcanoes erupt not in the ocean 在有些地方,火山不是在海洋中爆发的
but in the very middle of a continent. 但是在一个大陆的中部.
North America. 北美.
And in its very heart,a volcanic hot spot - Yellowstone. 在它的心脏,一个火山热点-黄石.
The last major eruption here 上次的大喷发
came to an end about 650,000 years ago, 大约在65万年前结束,
but this volcano is only sleeping. 但这座火山只是在沉睡.
Not far below ground,there is still magma. 离地面不远,仍有岩浆.
And that heats the ground water to boiling point. 把地下水加热到沸点.
Geysers. 间歇泉.
Some spout boiling water and steam to heights of 90 metres or so. 有的喷开水和蒸汽到90米左右的高度.
Elsewhere,the scalding waters liquefy the ground sediments, 在其他地方,滚烫的水使地面沉积物液化,
creating pots of boiling mud. 制造一盆盆沸腾的泥浆.
And this underground heating has proved a lifeline for some. 而这种地下供暖已经证明是一些人的生命线.
River otters. 河獭.
They need a constant supply of food if they're to keep warm 如果他们想保暖,就需要源源不断的食物
in these freezing temperatures. 在这么冷的温度下.
And this close-knit family know exactly where to find it. 这个关系密切的家庭知道在哪里能找到它.
The springs are so hot that the rivers never freeze, 泉水如此之热,河流从不结冰,
even in the coldest winters. 即使在最冷的冬天.
So the otter family can fish the year round. 所以水獭一家一年四季都可以捕鱼.
Trouble. 麻烦.
This coyote knows that in the middle of winter, 这只土狼知道在隆冬的时候,
a thermal river means otters, 热河意味着水獭,
and otters mean fish. 水獭是指鱼.
The question is how to steal their catch. 问题是如何偷他们的猎物.
Perhaps the thing to do is to pretend you're not interested 也许该做的就是假装你不感兴趣
and hope that they wander close enough for a snatch-and-run raid. 希望他们能走得足够近,以便抓捕逃跑.
It seems the cool-under-fire otters 看起来火下的水獭很酷
can outwit the not-so-wily coyote. 能胜过不那么狡猾的郊狼.
Many animals benefit from the volcanic heat 许多动物受益于火山热
coming up from below. 从下面上来.
And we do as well,but not nearly as much as we could. 我们也做得很好,但还没有尽力.
The volcanic heat could provide us 火山热可以为我们提供
with much of the energy that we need, 我们需要很多能量,
and then we could stop burning gas and coal 然后我们就可以停止燃烧煤气和煤了
that is now changing the climate worldwide. 这正在改变全世界的气候.
Deep in the Earth's crust, 在地壳深处,
below both the oceans and the continents, 在海洋和大陆下面,
there are lines of weakness along which rises liquid rock. 有软弱的线,沿着它上升的液体岩石.
The Kamchatka Peninsula in the north-west Pacific 西北太平洋的堪察加半岛
lies along one of them. 躺在其中一个旁边.
There are only a thousand known geysers in the world, 世界上已知的间歇泉只有一千个,
and many of them are here in this isolated valley. 他们中的许多人就在这个与世隔绝的山谷里.
Steam from superheated water fills the air. 空气中充满了过热水的蒸汽.
But the danger from the scalding pools does little to deter 但是滚烫的水池带来的危险并没有阻止什么
Kamchatka's most famous residents. 堪察加半岛最著名的居民.
In May,when the rest of Kamchatka is still covered by snow, 五月,当堪察加半岛的其他地区仍被积雪覆盖时,
this valley is free of it, 这个山谷没有它,
and bears,having just woken up from their winter sleep,know that. 熊,刚从冬眠中醒来,知道这一点.
The grass is fertilised by mineral-rich water 这种草是用富含矿物质的水施肥的
spraying from the geysers. 从间歇泉喷出.
Much-needed forage for a large male bear 大公熊急需的饲料
that hasn't eaten for several months. 好几个月没吃东西了.
And he's not the only one. 他不是唯一一个.
The bears haven't seen one another for seven months, 熊已经七个月没见面了,
since the start of winter. 从冬天开始.
And it seems that right now,they would prefer to keep it that way. 现在看来,他们更愿意保持这种状态.
Nothing should come between a bear and his first meal of the year. 熊和它一年中的第一顿饭之间不应该有任何隔阂.
And in one place,Kamchatka's underground forces 在一个地方,堪察加半岛的地下力量
provide its bears with even more nutritious meals. 为它的熊提供更有营养的食物.
Kurile Lake lies within the crater of an immense volcano 千岛湖位于一座巨大的火山口内
that long ago produced one of the greatest eruptions 那是很久以前最大的一次喷发
in the planet's history. 在这个星球的历史上.
The lake is still circled by active vents 湖泊仍被活跃的喷口环绕
and mineral-rich ash from their regular eruptions 以及它们经常喷发的富含矿物质的火山灰
has made these waters particularly fertile. 使这些水域变得特别肥沃.
Millions of salmon come here from the Pacific Ocean 数以百万计的鲑鱼来自太平洋
in order to spawn in these fertile waters, 为了在这些肥沃的水域产卵,
which will provide their newly hatched young with abundant food. 为刚孵出的幼崽提供充足的食物.
So,grass soon ceases to be top of the menu for Kamchatka's bears. 因此,草很快就不再是堪察加熊的首选.
By the time spring has turned to summer, 当春天变成夏天的时候,
Kurile Lake contains the most dense assembly of bears 千岛湖有最密集的熊群
to be found anywhere on Earth. 在地球上任何地方都能找到.
All hungry for salmon. 都想吃鲑鱼.
But this early in the season,the fish are still strong and swift. 但是在这个季节的早期,鱼仍然强壮而敏捷.
Nothing seems to work. 似乎什么都没用.
But one old bear knows that,right now, 但一只老熊知道,现在,
there is an easier meal to be had. 有一顿更容易吃的饭.
He remembers that if he paddles out into the lake, 他记得如果他划到湖里,
away from the shoals of newly arrived salmon, 远离新来的鲑鱼群,
there's food that doesn't need chasing. 有些食物不需要追逐.
Some of the first fish to arrive have died, 一些最先到达的鱼已经死了,
and their bodies can be easily collected 它们的尸体很容易被收集起来
from the bottom of the lake. 从湖底.
Diving for them at leisure doesn't use many calories. 在休闲时为他们潜水不会消耗很多卡路里.
And he can take his time. 他可以慢慢来.
A couple of weeks later, 几周后,
the salmon are beginning to spawn and are less wary. 鲑鱼开始产卵了,也不那么警惕了.
Now it's worth running. 现在值得一试.
The fish are so abundant 鱼太多了
that there is plenty for all 所有人都有很多
even those with no previous experience. 即使是那些没有经验的人.
There are now so many fish, 现在有那么多鱼,
it's difficult to know which one to chase. 很难知道该追哪一个.
In a single day,a bear can consume 100,000 calories, 一只熊一天可以消耗100000卡路里,
50 times more than the average human being does. 是普通人的50倍.
And one part is particularly delicious 其中一部分特别美味
caviar. 鱼子酱.
80 calories in every mouthful. 每口80卡路里.
By supporting huge concentrations of salmon, 通过支持大量的鲑鱼,
mineral ash from Kurile Lake's volcanoes 来自千岛湖火山的矿物灰
has made life surprisingly easy for these bears. 让这些熊的生活出奇的轻松.
Our planet depends on minerals brought up by volcanoes 我们的星球依赖于火山带来的矿物质
from the Earth's molten core. 从地球熔化的核心.
A single ash cloud can carry billions of tonnes of minerals. 一片火山灰云可以携带数十亿吨的矿物质.
And as a consequence,the lands surrounding volcanoes 因此,火山周围的土地
are among the world's most fertile. 是世界上最肥沃的地区之一.
Those in East Africa's Rift Valley 东非裂谷的那些
support the most dynamic ecosystem on Earth. 支持地球上最具活力的生态系统.
The Serengeti. 塞伦盖蒂.
This is the most productive of all natural grasslands anywhere. 这是世界上所有天然草地中产量最高的.
Every year,over a million wildebeest 每年,超过一百万只角马
assemble in this particular corner of the Serengeti 在塞伦盖蒂的这个角落集合
to feed on grass especially rich in calcium and phosphorus, 以富含钙和磷的草为食,
essential minerals for the pregnant females. 孕妇必需的矿物质.
In just three weeks,half a million calves are born 仅仅三周,就有50万头小牛出生
on these ash-rich plains. 在这些火山灰丰富的平原上.
That's 24,000 a day 一天两万四千
a thousand an hour. 一千个小时.
Calves stand up within a few minutes of being born. 小牛出生后几分钟就站起来了.
Though some need a little more time to find their feet. 尽管有些人需要更多的时间来站稳脚跟.
But a mother won't let her calf suckle 但是妈妈不会让她的小牛吃奶的
until it's mastered a few physical skills 直到掌握了一些身体技能
walking 行走
trotting 小跑
and running. 还有跑步.
Wildebeest calves must run if they're to stay alive. 牛羚幼崽要想活下去就得跑.
For these plains also support 对于这些平原也有支持
the greatest assembly of hunters on the planet. 地球上最大的猎人群体.
Each species has its own special hunting technique. 每个物种都有自己独特的狩猎技术.
But all have the same aim 但都有相同的目标
to make the most of this brief super-abundance of life. 充分利用这短暂而丰富的生命.
Only one in ten wildebeest calves will survive to adulthood. 每十头角马犊牛中只有一头能活到成年.
But that is enough to maintain the million-strong herd of wildebeest 但这足以维持百万只牛羚
AND the planet's highest density of predators. 以及地球上密度最高的食肉动物.
Volcanoes fertilise the planet, 火山使地球肥沃,
but they're the source of something else so important 但它们是其他如此重要的东西的来源
that life could not have started without it. 没有它,生活就不会开始.
The first carbon dioxide in the Earth's atmosphere 地球大气中的第一个二氧化碳
was brought by volcanoes from deep in the Earth's crust. 是由地壳深处的火山带来的.
And this gas is the foundation of life. 这种气体是生命的基础.
Every plant needs it to grow, 每种植物都需要它来生长,
and absorbs it from the air. 从空气中吸收.
Volcanoes continue to release carbon dioxide today, 今天火山继续释放二氧化碳,
and for the last 10,000 years, 在过去的一万年里,
its presence in the atmosphere has suited life perfectly. 它在大气中的存在非常适合生命.
Its greenhouse properties have kept 它的温室特性
our planet's climate stable and warm. 我们地球的气候稳定而温暖.
But too much carbon dioxide would make the planet's temperature 但是过多的二氧化碳会使地球温度升高
rise to levels that would upset the Earth's 上升到足以扰乱地球的高度
long-established ecological balances. 长期建立的生态平衡.
Today,humanity itself 今天,人类本身
has become a new kind of supervolcano. 已经成为一种新的超级火山.
Now,every year,we ourselves release 100 times more carbon 现在,每年,我们自己释放的碳是现在的100倍
than all the Earth's volcanoes combined. 比地球上所有的火山加起来还要多.
And that has brought climate chaos. 这带来了气候混乱.
We can't control volcanoes, 我们无法控制火山,
but we can limit the amount of carbon dioxide that we produce. 但是我们可以限制二氧化碳的产生量.
And if we do that,there will still be time 如果我们这么做,还有时间
to restore the ecological balance 恢复生态平衡
that once made this Earth our perfect planet. 曾经使地球成为我们完美的星球.
Lake Natron,in Tanzania 坦桑尼亚的纳特龙湖
is one of the world's most toxic bodies of water. 是世界上毒性最大的水体之一.
Yet once every few years,when the centre dries out, 然而每隔几年,当中心干涸时,
it's brought to life by thousands of breeding flamingos. 数千只繁殖中的火烈鸟给它带来了生命.
But to reach the colony, 但是为了到达殖民地,
there's only one way to cross this soft soda sludge. 只有一种方法可以穿过软苏打淤泥.
It's finally here. 终于到了.
Our secret weapon 我们的秘密武器
is a hovercraft. 是气垫船.
And it's beautiful. 而且很漂亮.
Having shipped it from the UK, 从英国运来的,
Darren's keen to test that all systems are go. 达伦热衷于测试所有系统是否正常.
Getting it off the trailer is one thing, 把它从拖车上弄下来是一回事,
but at least the hovercraft's fans,that give it lift, 但至少气垫船的风扇能让它升力,
are working well enough. 你工作得很好.
Well,guys,what do you think? 伙计们,你们觉得呢？
We know she works,but 我们知道她工作,但是
maybe some of these guys' lungs don't now. 也许有些人的肺现在没有了.
125 miles away,on the edge of Lake Natron, 125英里外,在纳特龙湖边,
cameraman Matt Aeberhard is trying to camouflage his hides. 摄影师马特·艾伯哈德正试图伪装他的兽皮.
Those are our blinds. 那些是我们的百叶窗.
So,you can't camouflage those on the flats, 所以,你不能伪装公寓里的人,
and the best thing that we can do is actually 我们能做的最好的事情就是
turn them into a little cluster of flamingos. 把它们变成一小群火烈鸟.
It's pretty cool,huh? 很酷吧？
Hide complete,all that's needed is transport out to the colony. 完全隐藏,所需要的只是运送到殖民地.
And after a ten-hour cross-country journey, 经过十个小时的越野旅行,
Darren arrives with his secret weapon 达伦带着他的秘密武器来了
and it's an instant hit. 这是一个即时的打击.
It's the new local tourist attraction. 这是当地新的旅游景点.
You like it? 你喜欢吗？
The first job is to get the hovercraft into service 第一项工作是让气垫船投入使用
and plot a route out to the nesting flamingos. 为筑巢的火烈鸟划出一条路线.
The volcanic spring water is soon replaced 火山泉水很快就被取代了
by a crust of razor-sharp salt crystals. 一层锋利的盐晶体.
And for a machine that relies on a delicate blow-up bottom, 而对于一台依靠精致的底部爆破的机器来说,
that's a problem. 这是个问题.
So,what we have here are the plates of dried out soda 所以,我们这里有一盘干苏打水
which form on the mud substrate underneath, 在下面的泥基上形成,
and it just batters the hovercraft. 它只会击打气垫船.
We just cannot travel across this stuff. 我们不能穿过这些东西.
It's impossible. 这是不可能的.
If I was to skim my hand across that,I would cut it to shreds. 如果我用手掠过那东西,我会把它切成碎片.
But crossing the soda crust is the only way out of to the colonies, 但穿过苏打皮是唯一的出路,
and so Matt and Darren have to hope for the best. 所以马特和达伦只能抱着最好的希望.
Unfortunately for Matt, 对马特来说很不幸,
the best position for his flamingo-covered hide 他的火烈鸟皮的最佳位置
has a rather soggy floor. 地板很湿.
When the mud dries,it leaves massive amounts of salt. 当泥浆变干时,会留下大量的盐.
Very scratchy,nasty and aggressive salt. 非常发痒,肮脏和侵略性的盐.
But sitting shin-deep in toxic sludge 但是坐在有毒污泥深处
is a price worth paying for the view. 这是一个值得付出代价的观点.
And Matt is soon rewarded with the birth of a chick 马特很快就得到了小鸡的出生
right in front of his hide. 就在他的兽皮前.
The daily commute,however, 然而,每天的通勤,
is taking its toll on the hovercraft 正在对气垫船造成损失
Oh,come on! 哦,来吧！
and its blow-up bottom is literally being ripped apart. 它的底部被炸开了.
We've trashed 52 of these that now need to be repaired. 我们已经扔掉了52个现在需要修理的.
It's like travelling over sandpaper. 就像在砂纸上旅行.
So,what do you do when your hovercraft needs 那么,当你的气垫船需要的时候你会怎么做
replacement skirts and you're in the middle of nowhere? 换了裙子,你就不知道在哪儿了？
Enter the local Maasai tribe, 进入当地马赛部落,
well known for their needlework skills. 以刺绣技艺闻名.
There are only a few places in the world that specialise 世界上只有少数几个地方专门从事
in hovercraft maintenance, 在气垫船维修方面,
and Lake Natron is now officially one of those hot spots. 而纳特龙湖现在正式成为这些热点之一.
So if you're in the need of any hovercraft services, 所以如果你需要气垫船服务,
you know where to go. 你知道该去哪里.
Two days later,and after a lot of serious sewing, 两天后,经过一番认真的缝纫,
the hovercraft is ready to ride again. 气垫船准备再次飞行.
You look like the new Tanzanian bobsleigh team! 你看起来像新的坦桑尼亚长橇队！
And getting back on the lake couldn't have come at a better time, 回到湖边再合适不过了,
as the chicks are now on the move. 因为小鸡们现在在行动.
Sadly,the new hide position is no drier. 可悲的是,新的藏身处并不干燥.
We have an enormous creche of hundreds of thousands of birds 我们有一个由数十万只鸟组成的巨大托儿所
just pouring into the lagoon from the salt mud, 刚从盐泥里倒进泻湖,
just constantly chatting to each other. 只是不停地聊天.
But the massive creche attracts some unwelcome visitors 但是巨大的托儿所吸引了一些不受欢迎的游客
predators - marabou storks. 捕食者-马拉布鹳.
These marabous,they know exactly what they are doing. 这些马拉布人,他们很清楚自己在做什么.
Soon,thousands of panicked chicks are on the move, 很快,成千上万惊慌失措的小鸡开始行动,
desperately trying to avoid the predators. 拼命躲避掠食者.
And it's a scene that will live long in Matt's memory. 这一幕将永远留在马特的记忆中.
I mean,it was literally like 我是说,就像
war had been declared. 战争已经宣战.
I mean,that's one of the the 我是说,这是
most amazing and frightening and freaky wildlife scenes 最令人惊异、恐怖和怪异的野生动物场景
I've ever,EVER seen. 我见过,见过.
And believe me,I've seen a few. 相信我,我见过一些.
And few places are more challenging than Lake Natron, 没有什么地方比纳顿湖更具挑战性,
but to quote Matt,if you can deal with 但引用马特的话,如果你能处理好
the acrid and sulphurous stink of the soda, 苏打水的辛辣和硫磺味,
the stinging eyes and the chemical attack on your legs, 刺痛的眼睛和你腿上的化学物质,
then you could be rewarded with one of the greatest spectacles on Earth. 那你就可以得到地球上最壮观的景象之一.
Next time 下次
the sun. 太阳.
Life on our planet is fuelled by its energy. 我们星球上的生命是靠它的能量来维持的.
Everything must be perfectly tuned 一切都必须调整得很好
to the daily and yearly rhythms of this vital force. 每天和每年的节奏.
The Open University has produced a free poster 开放大学制作了一张免费海报
exploring our perfect planet. 探索我们完美的星球.
To order,please call 0300 303 0901. 如需订购,请致电0300 303 0901.
Or go to bbc.co.uk/perfectplanet 或者去bbc.co.uk/perfectplanet
and follow the links to the Open University. 并按照链接到开放大学.