[mikewave]

I'm no farmer, but I'm all ears! If you have dry useless soil and can't water it, does it not have some residual value as an export product?

I suppose this is assuming that there's not going to be water in the future, and that you just want to extract whatever use there is left from an area before giving it over to desertification.

[moralestapia]

Soil, and topsoil in particular, is an extremely valuable and non-renewable resource. When land becomes barren it could take 100s of years to regenerate, or it may never do, as in this case this is a desert and for this process to happen you need a continuous stream of biomass and microbes doing their stuff.

If they did this, in a couple years they still wouldn't have water, and now they'd also wouldn't have land to pour the water onto, so they will end up in an ever worse state than now.

[stewarts]

While not worthless, as there would still be nutrients present. A good bit of soil quality comes from the microorganisms within it.