actually, there is proof (we measure the acidity of the rain and the damage of the forrests). The latter don't recover. it's just that we substituted the damaged conifers by different species that are more resistent to acidity.
As for the consequences: I tried to describe them in my previous post and I think the list is rather impressive. I can assure you that none is imagined but we're talking about actual damage here. I live in the affected area and see the damage every day. (I did mention that I've been working for the Ministery for Man and the Environment these 20 years, or did I forget?)
The catastrophical flood we had half a year ago was an immediate consequence of deforrestation. The pictures were in the news all over the world, so I think I needn't link to them. I happen to live in the town affected worst.
If you live in a country or area that is not (yet) affected you can only be envied. I hope you are aware of how lucky you are.