How does Aldo Leopold use imagery in A Sand County Almanac?

Imagery:

"It is a river who wields the brush, and it is the same river who...erases it forever from human view. After that it exists only in my mind's eye."

"A conservationist is one who is humbly aware that with each stroke he is writing his signature on the face of his land."

"In wildness is the salvation of the world. Perhaps this is the hidden meaning in the howl of the world, long known among mountains, but seldom perceived among men."