How does the poet describe nature in the poem "The Eagle"?

This is an interesting question. The poem is only six lines, and about half of those lines are dedicated to describing the eagle. On one hand, you could make a claim that the eagle is part of the nature that the question is asking about. On the other hand, you could claim that the eagle exists outside of the nature that this question is asking about; however, I don't feel it is appropriate to separate the eagle from nature. Nature is all about the interdependence of abiotic and biotic factors within any given ecosystem. Removing any one of those factors can create huge problems for nature; therefore, I believe that the eagle and nature should be treated as one. If I had to pick just a couple of adjectives to describe nature in this poem, I would say majestic and powerful. The eagle is presented to readers as being high up. He is close to the sun, or watching from mountain walls. It's a ruling position. Kings are set up on thrones that are elevated above ground level. Even Simba from The Lion King was presented to his kingdom from a high mountain overlook. The eagle is also "ring'd" in the way that a king's head is ringed with a crown. As for the powerful aspect of nature in this poem, the eagle "clasps." He doesn't gently hold. His powerful wings allow him to be close to the sun, and he descends with the intensity of a thunderbolt; he doesn't gently float to the ground.

Nature is used in the poem as a way of highlighting the characteristics of the eagle. The eagle, though an animal and therefore part of the natural world, is at the same time set apart from it. His strength and vitality are contrasted to the "wrinkled sea" beneath him, the sea that "crawls." The sea is being presented here almost as if it were an old man, whereas the eagle is young and full of vigor, able to swoop down suddenly like an almighty great thunderbolt.
Other features of the natural world are used by Tennyson to provide a dramatic background against which the eagle's majestic bearing shines forth. He is "ring'd with the azure world," surrounded by the blue of the sky above and the ocean beneath the mountain on which he stands. Crucially, the eagle clasps the crag, not with feet or claws, but with "hands." Tennyson's use of the word serves once more to illustrate the clear distinction between the eagle and his natural surroundings. There is something almost human about him.
https://www.poetryfoundation.org/poems/45322/the-eagle-56d224c9a41d1