What training camp sights soothe Paul's mind and what does he think of the Russian POWs?

At the training camp, Paul seems to derive a measure of pleasure from the beauty of nature.  Unlike the first time he was stationed there, Paul has no friends among the soldiers.  This leaves him time to ruminate about his surroundings, which are ironically quite lovely, especially "the play of soft light and transparent shadow".  Paul takes comfort from the sight of

"the grasses and the flowers of the heather...the fine sand (that) is composed of millions of the tiniest pebbles...but most beautiful are the woods with their line of birch trees".

Paul observes,

"It is when one is alone that one begins to observe Nature and to love her".

During this time, Paul is often assigned to guard the Russian prisoners being held at the camp.  Paul says,

"It is strange to see these enemies of ours so close up.  They have faces that make one think...I know nothing of them except that they are prisoners; and that is exactly what troubles me...I perceive behind them only the suffering of the creature, the awful melancholy of life and the pitilessness of men".

The realization of the humanity of the "enemy" causes Paul to think about the true absurdity of war.  He wonders that

"a word of command has made these silent figures our enemies; a word of command might transform them into our friends...but who can draw such a distinction when he looks at these quiet men with their childlike faces and apostles' beards.  Any non-commissioned officer is more of an enemy to a recruit, any schoolmaster to a pupil, than they are to us.  And yet we would shoot at them again and they at us if they were free".

Paul understands that his thoughts are moving in a dangerous direction.  To fully examine the ridiculous truth that men much like himself are his sworn enemies because of a declaration of governments is to embark on a path that is too disturbing to consider (Chapter 8).