ratios are quite tricky. one sunk tanker ship can poison sqare miles of the ocean. Imagine if once a day one tanker would sink. sure we have lots of ocean left but for how long.
the "natural rapair" sytem is sloooooow.
if you continue to spill out posion into a river sooner or later it will die. Simply because the regeneration is slower then your poisoning.

if you at the same time continue to cut down whole forrests, getting rid of the co2 wont get easier at all.

i have no doubt that we are [censored] up this planet with a mankind masterplan. and sooner or later its either mother natur or us. and i doubt this is a situation we can win.

cheers