How does Percy Shelley's treatment of nature differ from earlier romantic poets?

Earlier Romantic poets were writing during the time of the American and French revolutions, as well as the beginning of the Industrial Revolution. The tone of energy, transformation, renewal pervaded the poetry of the time, often appearing as a "back to nature" theme. The idea of nature became a source of refuge from the artificial and lent an aesthetic, spiritual air to much of early Romantic poetry. Wordsworth, for example, presented nature in a philosophical light, with nature being the primary subject of many of his poems. Both he and Coleridge wrote of the healing, majestic, god-like power of nature.
Shelley, however, often included nature merely as part of a poem, or even as the backdrop to other themes and images. Although he wrote of the mystical beauty of nature, he also presented nature’s tendency towards dark power, which cannot be fully controlled by humans. For example, in "Stanzas Written in Dejection, Near Naples" he writes:

And I might feel in the warm air
My cheek grow cold, and hear the sea
Breathe o’er my dying brain its last monotony.

Nature here is indifferent to the suffering of man, and the poem is more about the speaker’s dark mood than it is about the nature around him. In "Ozymandias," we see the indifferent power of nature as it erases all evidence of a man who saw himself as a god. The plaque at the feet of his time-ravaged statue reads:

My name is Ozymandias, King of Kings;
Look on my Works, ye Mighty, and despair!

Yet we see that nature has not only destroyed his statue but his entire kingdom and the memory of whom he was:

Nothing beside remains. Round the decay
Of that colossal Wreck, boundless and bare
The lone and level sands stretch far away.

Again, the theme centers more on the insignificance of man than on nature, which Shelley presents as beautiful and powerful, but not benevolent, as the early Romanticists envisioned.
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