I have no problem imagining any of those things.
The issue many of us face is that of first steps. How do we get there from here?
I think I would simplify my approach significantly by focusing on supporting keystone species, and working towards their reintroduction in areas from which they'd previously been extirpated.
One excellent example of this is the beaver. Granted, there would need to be infrastructural changes implemented so that their activities don't impact roadways, culverts, and bridges, but bringing the beaver back to it's original habitat would increase water infiltration and aquatic ecosystems, and would keep forests green when they'd otherwise become fire hazards. True, fires will sweep through regardless of what we do, but the fuel load will be greatly decreased, owing to greener undergrowth.
In some places, reintroducing beavers will
boost aquatic system health in estuaries and water courses significant to salmon survival, which in turn feeds several systems throughout their lifecycles, terminating in their becoming food for bears and other critters.
If we really want to assist ecology to a significant degree, I think that rewilding is such an idea. I think reintroducing extirpated species or their analogues to areas in crisis is a terrific way to set biological controls in place. I think, for instance, that an engineered species consisting of the Asian Elephant with added or swapped woolly mammoth DNA would be an amazing new keystone species for the upcoming northern grasslands. I think that they, along with reintroduced bison from further south, would do well on the former permafrost. Adding beavers and the riparian tree species and corresponding guilds would hold fresh water in the landscape and add more aquatic biome.
We'd have two types of megafauna in the mammophant and the bison, beavers would replace the giant beavers of the pleistocene, and wetlands created by their activity would draw elk, which would draw wolves. And there are something like 22,000 to 31,000 polar bears that would suddenly have an easier time adapting to ice-free summers, until they have babies with grizzlies.
That would count as assisting ecology significantly, in my
books.
-CK
A human being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, analyze a new problem, pitch manure, program a computer, cook a tasty meal, fight efficiently, die gallantly. Specialization is for insects.
-Robert A. Heinlein