What is the role of the landscape in the novel, and how does the novel develop the relationship between man and enviorment into a theme?I'm having...

There is a good answer to this question at the link below
under "style" for the guide on this novel.

Cather's writing
style is strong and vivid, but unadorned. She very carefully depicts the environment of
the Nebraska prairies and in her descriptions, shows how the people are connected to the
land. The weather, the colors, the seasons, the droughts, the crops are all woven into
the story and reveal something about the characters and their relationship to their
environment. One of the themes of this novel is how immigrants helped the United States
grow into a great melting-pot country and how important immigrants were to "the American
Dream." This novel paints a wonderful picture of the pioneer
experience.

Some examples - everyone looks forward to
summer after the long, bitter cold Nebraska winters. Ántonia tells Jim she cannot
imagine how anyone would want to die in summer. When Mr. Shimerda kills himself, it is
winter, and his blood freezes around his body. When Jim comes back to visit Ántonia at
the end of the novel, he passes the land in which he grew up on a train. While he is
traveling through Nebraska, he sees rich farmland, animals and their young -- abundance
everywhere. This is a stark contrast to the city, where he is coming from, and his life,
which is empty. He is divorced and he has no children. In contrast, Ántonia, who has
remained on the land, is happy, fulfilled and has a ton of children, an abundant farm
that is well-stocked with animals, and bursting forth with produce. Jim is unhappy
because he has separated himself from the land, whereas Antonia is happy because she has
remained and grown symbolically "rich" along with the land.