What is the effect of people cutting too many trees down for buildings houses lumber and paper?

Well, by cutting down trees air becomes dirty, people sufficate eventually, the air is too dirty to live in, animals lose homes too so cutting down trees all leads to a chain reaction. Trees provide air and mammals need air to survive. Trees clean air so without trees the pollution would really be noticable. If there is no filter for the air people would be breathing pollution which will eventually be VERY bad.