'Salt' in the Bible

My Strength, I will sing praises to you, for you, God of Gracious Love, are my fortress. To the Director: A special Davidic psalm to the tune of "Lily of The Covenant," for teaching about his battle with Aram-naharaim and Aram-zobah, when Joab returned and attacked 12,000 Edomites in the Salt Valley.

{To the chief Musician upon Shushaneduth, Michtam of David, to teach; when he strove with Aramnaharaim and with Aramzobah, when Joab returned, and smote of Edom in the valley of salt twelve thousand.} O God, thou hast cast us off, thou hast scattered us, thou hast been displeased; O turn thyself to us again.

A fruitful land into a plain of salt, for the wickedness of them that dwell therein.