Nice job
Looks like a dread that's seen some action and has the battle damage to prove it.
Regarding the base, generally you'd use plain ol white PVA glue for keeping the material on the base. For basing like this after the model is painted, usually you'd do a layer of PVA on the base, sprinkle the basing material on, leave it to dry, and then put a layer of watered down PVA over the top of it all to seal it in. If its watered down enough, then it'll form a nice protective layer over the base and not obscure much of the texture. You could then apply a wash for some shading, or a bit of dry brushing for some highlights.
Hope that helps!
Regards