It is likely that either the forestry or mining industry will become obsolete explain?

No, neither will become obsolete. As the population grows, more stuff needs made to clothe, feed, shelter and entertain. If you can't grow it, then it has to be mined. So until we can make recycling technology 100% efficient (thermodynamically impossible) then we will need to get more material from the earth, or grow it.

With forestry would you prefer a house of wood or steel? How about your bed, carpet. As more 'green' industries come out, the more they have to rely on forestry products as forestry is actually more sustainable.