Fourth edition (PHB page 266) defines a turn as the 6 seconds during which you, the player, take your actions. A round is the same 6 seconds, during which everyone takes their turn. So, 1 round = 1 turn = 6 seconds.
As far as I can tell, 4e is silent on the issues of non-combat time, movement, and encumbrance. The closest related rule I found was the table about duration of light sources (PHB page 262), which specified that a candles and torches last 1 hour, and a lantern burns for 8 hours per pint of oil.