Once you start packing everything you think you’ll need to establish a new biosphere you start running into what I call the “Noah’s Ark” problem pretty quick. You want to bring a pair of lions? Better make sure you have a breeding population of zebras to keep them well fed! And that means a whole lot of grass. And of course you’ll need lots of soil additives and nutrients and microbes and whatnot to keep the grass alive. And so on.
Even if the only species you ultimately care about keeping alive is humanity we aren’t exactly sold separately.
