If we did not bury our dead, would it be possible to distribute the human remains as fertilizer?

Cremated human remains make for a most excellent fertilizer. Toxins in the human body are released during the cremation process leaving a near perfect balance of nitrogen, phosphorous, potassium, calcium, iron and magnesium. All the necessary ingredients for happy soil.

Not practically, no.

Best way would be to STOP embalming corpses and planting valuable trees on top of the graves, like fruit and nut trees. They could even make pulp or xmas tree farms from organic graveyards and never have to worry about fertilizing. But that's too "icky" for most humans to accept.

As much as I suspect you're trolling, I'll answer it straight.

It's not a good idea to add human remains to a compost for the same reason you should avoid adding meat and dairy in general to your compost. Unless it's a really hot compost, it will stink, and attract vermin.

Cremated remains would be safe to add to your compost pile.

I believe there are acids and chemicals in the body that would be poisonous to edible plants. I'm sure after time it would be ok, but recently deceased people thrown on the ground would most likely not be the best way to help produce food.

Um sorry I'm not the Isaac your looking for. But I agree with the answer at the top