Custom landcape with bluesprint

Hi everybody,

I have a field that I join, and I would like that ground is separated in grid of 10 by 10 and that each of the parts is manipulable but I can not find a solution, (for example I click on a part of the grid and its moves down only this part (with vector), and without destroying the object and keeping the connections so as not to have a big hole everywhere)
that is all,

thank you in advance,
Bests Regards,
Nicolas