What would happen if we destroy all the life forms on earth :surprised ? Then we grow the trees and plants and some organisms(somelike dogs and cats could be replaced by robots ) which are necessary only for out survival? We could mark the amzon forest and other tropical areas reserved for forests and remove all humas from there. Bring water from Mars. Pollute seas and rivers. Or we could pollute some oceans and leave others clean? And create inland reservoirs for water.