The island is described as a place of natural beauty. The way that the different characters react to it shows something about their character. Jack sees nature as something to conquer, to defeat. Simon sees the beauty that is already there. Ralph sees it as a place where resources can be found, such as wood for a fire or bushes, sticks, and leaves for shelters. The weather also plays an important role in the story. As the boys become more savage, the weather worsens. This can be seen as a statement that the more cruel humans are, the worse we make the world around us. The evil inside each person, or the good, and how we act on these primitive instincts, is how we determine what the world will be, together.
Early Romantic's thought mankind to be living in a naturally perfect state of nature until ruined by Society (Rosseau). The natural environs in LOF mirror the "state of nature" that the boys find themselves in. Golding opposes Rosseau's view with a more Biblical one, advancing the belief that we are not perfect in a state of nature, but are inherently evil. The "perfect island" backdrop serves as a staging point for showing the ruin we would bring left to our own devices. The island is in a pristine state before the plane crashes; it is a pastoral setting reminiscent of the Garden of Eden before the "Fall," because there is the symbolic reference to the fall of Adam and Eve due to original sin, and the fall of the airplane from the sky. The plane leaves a visible scar, as Golding describes it, on the side (face) of the mountain--literally and figuratively disfiguring the landscape.
This is, of course, something that the boys also do. As the robes and clothes come off, as the face of the island is "man-handled," through the shabby buildings and the trash (and especially through the diarrhea---literally defecating in Paradise), Golding advances his motif of mankind's desructive nature, his inability to avoid his inate savagery when he has lost the civilizing restraints that human society imposes on us in the name of order. The end result is that, like the atomic-war ravaged "big" world (macrocosm), the small world of the island (microcosm) is left in fire and ruin.