"Land" doesn't mean just the stuff you can hold in your hand. It literally has several pages dedicated to it in the OED. The big one. "Ground" too.

It so happens that the word for "dirt" in many languages acquire meaning that transcends mere silica and humus, as our Japanese friend pointed out.

And why would this surprise anyone? "Terroir" is using the word for "ground", "land" as a poetic metaphor for everything needed to make a peasant happy (as opposed to content).