I remember reading some article about deserts, and how, even when they seem completely empty of life, they actually have entire tiny fragile ecosystems living just under the sand. The article was in favor of imposing restrictions on dune buggies in a couple deserts where the activity was growing out of hand, because wherever the buggies went, that fragile ecosystem was just wiped out. And with the harsh conditions, it takes a really long time for them to recover.