Mother trees are a crucial keystone in regeneration of forests.

母树是森林再生的重要基石。

We hope to see you become a keystone of the intellectual community.

我们希望看到你们成为这知识型社区的一块拱顶石。

So polar bears are an economic keystone in Churchill, driving tourism and creating jobs.

所以北极熊在丘吉尔成了经济基石的一部分，推动旅游业和创造就业机会。

Sharks are keystone species in the world's oceans.

“鲨鱼是世界海洋中的关键物种。

So these water towers are keystone to our future.

因此，这些水塔也成为了我们未来的基石。

Manatees are what's known as a " keystone species."

海牛因其“关键种”身份而著名。

So another term for that is Aspen is a keystone species.

换句话说，山杨是关键物种。

For example, a science reading might explain what a " keystone species" is.

例如，一篇有关科学的文章可能解释关键物种是什么。

This is biden's second visit to the keystone state this week.

这是拜登本周第二次访问拱心石之州（宾夕法尼亚州的别称）。

What Hawaiian keystone species is currently under threat from a fungal infection?

夏威夷的什么关键物种目前正受到真菌感染的威胁？