What is difference between preserve and conserve?

Preserve is to keep it untouched and as is. Conserve means to use it, but wisely and sparingly. For the environment, conservation is good, and preservation is better. Yes many think that preserving nature is good, but if humans don't use it, than what good is it to us? Why should we lock the environment in a display case just for show? Why should we do that to a thing that is so beautiful and helps husmans grow and live?