The good old days

I remember those good old days, when the air was clean to breathe, water was clear to drink and the land was full of fresh green vegetation to have healthy food. However a lot of environmental problems now affect the entire world. I am even unable to breath due to this pollute air. Today to drink some fresh water, it has to be purified using several methods. We can find fresh green vegetables no more. According to me, of the various kinds of problems faced by our planet, the depletion of non-renewable natural resources is the major concern.