And it is He who spread out the earth, and set thereon mountains standing firm, and (flowing) rivers: and fruits of every kind He made in pairs, two and two: He draws the Night as a veil over the Day. Verily in those things there are signs for those who consider. (Quran: Chapter 13, Verse 3)

It is God Who sends down water (rain) from the sky, and with it We bring forth vegetation of all kinds, and out of it We bring forth green stalks, from which We bring forth thick clustered grain. And out of the date palm and its sheaths come forth clusters of dates hanging low and near, and gardens of grapes, olives and pomegranates, each similar (in kind) yet different (in variety and taste). Look at their fruits when they begin to bear, and the ripeness thereof. Verily, in these things there are signs for a people who believe. (Quran: Chapter 6, Verse 99)

It is God who has let free the two bodies of flowing water: one palatable and sweet, and the other salt and bitter; yet has He made a barrier between them, a partition that is not to be passed. (Quran: Chapter 25, Verse 53)