I have roots on top of the ground where I want to lay a 10' x 15' x 6" slab of concrete. These roots are 1" tall fron top of ground. Will they grow up and upheave or crack the concrete if I leave them and lay my slab on top of them?

Chances are yes they will, but more likely the tree or bush will dye after removing the roots. Best would be to remove the source of roots completely.