纪录片《我们的地球》 第179期 多样浅海(13)（在线收听）

By midsummer, the surface nutrients have all been absorbed.

直到夏至，海洋表面的养分全部被摄取。

The algae die and the food chain collapses.

藻类死亡，食物链因此崩溃。

In a few special places, however

然而在少数特别的地方，

the temperate seas sustain these levels of life throughout the summer.

气候温和的海域维持这个生命水平贯穿整个夏季。

Along the coast of California,

在加利福尼亚沿海，

ocean currents carry a constant supply of nutrients up from the depths to the surface layers.

洋流持续不断的把养分从海底带到海平面上来。

These upwellings fertilize forests of giant kelp, that thrive in the summer sunshine.

这种上升洋流给巨藻带来了大量养分在夏日阳光照射下它们飞速生长。

The algal towers are as high as a three story house, and they can grow by half a meter a day.

这片巨藻林有足有三层楼那么高，它们每天还能长半米。

Life in the kelp is as full of drama, as in any other forest, but the cast is less familiar.

海藻中的生命充满戏剧性，跟其他森林一样，但演员们仍不太为人知。

An army of sea urchins is mounting an attack.

一大群紫海胆正在发动进攻。

The urchin plague strikes at the kelp's holdfasts their crucial attachments to the rock.

海胆们正在吃巨藻的固着器--把巨藻固定在石头上的重要装置。

Holdfasts are extremely tough, but each urchin has five teeth,

固着器非常坚硬，但是每只海胆有5个锋利的牙齿，

which are self sharpening and are replaced every few months.

而且每隔几个月就换牙。

Urchins fell vast areas of kelp forest,

海胆吃掉了大片的海藻森林，

creating clearings know as urchin barrens, yet barrens is a poor description.

把它们变成了不毛之地，无法形容的荒凉。