During this time of plenty, the foxes will bury any extra food, digging right down to the permafrost layer beneath.

在这食物充沛的时期，狐狸会将多余的食物埋藏起来，它们一直挖到地下的永久冻土层。

So the conclusion is that you're actually impacting into ice like northern Canada permafrost layers, a tundra kind of stuff.

所以结论是实际上撞击到了冰，就象加拿大北方的永冻层，冻土带一样的东西。

The top active layer stays frozen during the winter and spring but thaws in the summer time when the permafrost layer remains frozen all year long.

顶层活动层在冬季和春季保持冻结，但在夏季会融化，冻土层全年都保持冻结状态。