Skulls in the Wilderness

Here is a slightly more macabre photograph which has no identifying marks. I have a theory it was taken on a battlefield some years after a war. So why? Well, I think the discarded tins contained soldiers rations.

Identifying the location is problematic. I suspect it might be Gallipoli. What confuses me is the cacti. Does this Turkish peninsular have the terrain to support the growth of cactus? If not, then I am baffled. Would any of you care to offer an explanation, please?