The vegetation type that will be the most affected from the surface warming are the forests.
The forests will start to decline as the surface warming increases, and this is because the forests need more moderate temperatures, or if its warmer than to have a very big amount of precipitation. This is not the case when a global warming occurs, and deeper into the mainland where most of the forests are located, the precipitation will reduce, and that combined with the higher surface temperature will cause the forests to slowly die out in those places. As the forests start to diminish, they will be systematically replaced by grasslands of different types.