Above the tree line there is a zone that is generally called alpine tundra.

林木线以上区域通常被叫作高山冻。

So, if you're planning on exploring the frigid tundra Hoth-style, it might be helpful.

所以，如果你计划像在霍斯一样寒冷的冻探险，它可能会有所帮助。

He must have fallen off somewhere out on the tundra.

他肯定在冰的某个地方摔下来了。

Beavers may be following the northward expansion of vegetation onto the tundra.

海狸可能在追随冻植被向北扩展的脚步。

As the tundra is very windy, this causes deep drifts to surround the shrubs.

为苔经常刮风，这会导致深处的水流包围灌木丛。

The tundra is released from its prison of snow and ice.

苔被从冰雪的牢中解放出来。

But which places—Arctic tundra or Amazon rainforest—are most vulnerable to such climate change?

但那些地方更容易受到气候变化影响呢？北极苔亚马逊热带雨林呢？

For lemmings, small fussy rodents, there is no place more comfortable than the Arctic tundra.

对于旅鼠这种小而挑剔的啮齿类动物来说，没有比北极苔更舒适的地方了。

And her hands were like two frozen chunks of tundra.

她的手就像冻上的两个冰块。

" Let us gather tundra grass and thatch the roof, " Maud said.

" 我们去弄苔草苫屋顶吧。" 茅德说。

They report today that a white-spruce population has migrated surprisingly far north into the Arctic tundra.

他们今天报告说，令人出乎意料，一批白云杉向北迁移到了北极苔。

The birch is racing over the tundra faster than the pines can keep up.

桦树在苔上生长的速度比松树的速度快。

The transition from forest to treeless tundra on a mountain slope is often a dramatic one.

山上树带界线的植被。

Arctic hare is a mainstay of the tundra diet and one the cubs seem particularly keen on.

北极野兔冻主要的食物小家伙们貌似对这一食物情有独钟。

Strong winds hurtled off the frozen sea, and thick fog and clouds hung low over the tundra.

强风席卷过冰冻的海面，浓雾和乌云沉沉的压在冰上空。

As far as the eye could see the tundra of the plateau was flecked with black streaks.

在目光所及之处，高的苔上布满了黑色的条纹。

" Let's go back, " I said dejectedly. " I think tundra grass, will do, after all" .

" 咱们回去吧，" 我沮丧地说，" 我觉得归根到底苔草也可以用。"

Their plumage changes little with the seasons and their nests are easy to spot against the exposed tundra soil.

它们的羽毛几乎不随季节而变化，而它们的巢穴在苔上裸露的泥土映衬下极易被识别。

In spring, hundreds of millions of birds make the annual trip to the arctic tundra.

春天里，数以亿计的鸟类像往年一样踏上了前往北极苔的旅程。

Won't the shrub stop and it'll turn back into tundra?

灌木丛会停止生长并变回苔吗？