Specific runes have different duration of effect:
Magic wall - 20 sec
Wild growth - 45 sec or until chop it down
Fire Bomb - 5mins 48 sec (of blocking monsters ability) and 1mins 38 sec (it doesn't block monsters during this time)
Fire Wall - the same as Fire Bomb
Fire Field - the same as Fire Bomb
Energy Bomb - 1mins 38 sec
Energy Field - the same as Energy Bomb
Energy Wall - the same as Energy Bomb
Poison Bomb - 4mins 8 sec
Poison wall - the same as Poison Bomb
Poison field - The same as Poison Bomb
Chameleon - 3mins 20 sec
Soulfire - depends on level and magic level of character
(ex. Level 27 with Magic level 31 lasted for 20 turns;
Level 105 with Magic level 68 lasted 57 turns)
In addition, some runes may also harm You during some time by taking damage.
For example: Fire field - 7 turns x 9sec or Poison Bomb - 46 turns (if not cured)