纪录片《我们的地球》 第46期 淡水资源(03)（在线收听）

Invertebrates dominate these upper reaches.

无脊椎动物统治着上游河段

The hellgrammite, its body flattened to reduce drag,

这是鱼蛉，其扁平的身体能减少水的冲击力

has bushy gills to extract oxygen from the current.

并依靠浓密的鳃从水中过滤氧气

Black fly larvae anchor themselves with a ring of hooks.

蚋的幼虫靠钩环固定自己

But if these become unstuck, they're still held by a silken safety line.

即使不小心松脱了，它们还有一根坚韧的“安全索”

There are advantages to life in the fast stream.

这些动物拥有在急流中生存的先天优势

Bamboo shrimps can just sit and sift out passing particles with their fan-like forearms.

拟匙指虾只需趴在河底，用它们的扇形前臂从流水中过滤出食物颗粒

Usually these mountain streams only provide enough food for small animals to survive,

通常，山涧提供的食物只能维持小型动物生存

but with the spring melt here in japan, monsters stir in their dens.

可是在日本，每当春雪消融之际，一种怪物便在巢窟中苏醒。