What are some potential changes that would lead to a positive impact for something on this planet that man himself changed originally that is now a problematic issue? It needs to be an original idea but I can't think of any

recycling the right things in the right places - for example, receipts cannot be recycled, and if they are out into paper recycling then this can often cause problems and a whole batch of paper to be recycled can be ruined. this means that a whole bunch of stuff has to go to waste.