Interesting. I would have guessed that any kind of forests have quite limited cap how much carbon it could retain in dead wood, and that this cap will be pretty much fixed. Unless something will stop natural decay processes releasing the carbon back to the atmosphere I don't see how existing grown forest could increase its capacity, since I suppose it is already at its equilibrium.
(Unlike peatlands, where most of accumulated carbon remains underwater, so it presumably has much larger capacity.)
Simply said, without "burying or sinking wood mass" I see no easy way to prevent carbon from returning into the atmosphere. Basically if we need to take carbon from the atmosphere, we should ideally put it back from where we have been mining it for last couple of centuries.