What are the specific roles nature has played in poetry?
Nature has played a role in many different periods of literature. Perhaps the two most important periods in which nature held a very important role are those of Romanticism and Naturalism.
During the Romantic period, 1800-1860, nature's role in society was one that was erected as a contradiction to the previous literary period, The Age of Reason. For Romantics, nature was important because it exemplified the importance of imagination and denounced the importance of limiting rationalizations. Nature, for the Romantics, exemplified the importance of creativity of the human mind. Nature became a meditative function for the authors of the period.
The Naturalistic period (1880-1940) placed a very different importance on nature. Typically nature was personified given the power that nature held over man. Influenced by both Herbert Spenser and Charles Darwin, Naturalistic literature tended to place more power in the hands of nature and man was left to simply survive- if nature allowed him to. Free will did not exist given nature held all of the power. Imagery in Naturalistic texts tended to personify mines and ordinary characters using terminology related to nature. Mines were described as monsters or beasts that would swallow men whole (Germinal- Zola). Here, Nature (personified to show highest power) held all of the power.