Climate change, over-population and the depletion of natural resources are basically the result of human greed, selfishness, lack of self-control and the lust for power. Simply put, this is a reflection of the degeneration and degradation of the human spirit, resulting in all the woes our poor mother earth is suffering today. There is only one hope to save our dying planet and that is if spirituality can be restored in mankind. And what better way to restore this hope is through the teaching of our Lord Buddha Shakyamuni.
However we must also acknowledge that if everyone also practice the true essence of their own other religion in this world, our planet need not be in such a miserable state.
So to answer Redlantern's question, yes Buddhism, or the true spiritual practice of other religions, can save the Planet.