Hmmm. I found one example of what might be considered onomatopeia in the phrase "A snowstorm of cotton-grass seeds blew past her face." As critic M.H. Abram notes, "there is no exact duplication of non-verbal by verbal sounds; the percieved similiarity is due as much to the meaning, and to the feel of articulating the words, as to their sounds."
Alexander Pope says that "the sound should seem an echo of the sense."
As the wilderness in this novel is as much a character as Julie herself, you can surely find many other more approriate examples of language that mimics the senses.
A Glossary of Literary Terms, 7th ed.
Ft. Worth: Harcourt Brace, 1999