Yes, to some extent˙if water is penetrating˙the cellar from above.
BUT˙the predominant cause of dampness in a cellar is˙lateral water pressure from the surrounding ground and without the installation of a waterproof system to the floors and walls, this will continue unabated.
If anything, concreting over the garden will increase the risk of water penetration because˙it will mean the faster run-off of surface water˙which currently˙tends to be absorbed by the garden and so released more slowly. (You may have read press commentary˙on this point in discussions about the increased incidence˙of flooding in built up areas).