Honestly, Enviros are constantly saying "such and such will be gone in ten years"... Recently, they've gone down to six or four years, because our attention span is lower. At this point, the planet doesn't even have enough time to globally warm enough to kill us before the next ice age.
If you don't believe human beings can reasonably steward our farmable food sources, you're simply blind to history. What's more, if you honestly think that human use of natural resources is the problem, your only reasonable response is to kill yourself.