Concerning Coleridge's attitude toward nature, I'll tackle "The Rime of the Ancient Mariner" and let another editor handle "Kubla Khan."
The destruction and suffering experienced by the ship and the mariners is brought on by a senseless act of destruction. The ancient mariner kills an albatross for no good reason. He shows a terrible lack of respect for nature, for creation. All of creation possesses value in the poem, and the senseless destruction of any part of nature is a serious offence.
As the mariner says:
Farewell, farewell! but this I tell
To Thee, thou Wedding Guest!
He prayeth well, who loveth well
Both man and bird and beast.
He prayeth best, who loveth best
All things both great and small;
For the dear God who loveth us,
He made and loveth all.
Coleridge's respect for and love of nature is powerfully presented in his "The Rime of the Ancient Mariner." To phrase his views of nature in the poem in modern terms, we might say that Coleridge is suggesting that humans should be stewards of nature, not destroyers.