In my world a powerful entity decided to take a brute force approach to terraforming by picking a planet with a similar orbit and gravity to Earth and literally copy and paste vast swarths of the Earth onto the surface. This results in it dumping various copies of plants, animals, as well as water and air semi-randomly onto a completely separate world. I am wondering what a realistic time frame for this new biosphere to settle down after this sudden change. I imagine there would be an initial die-off period as various plants and animals failed to adjust, but I am curious on how long for things to normalized.
A few centuries for semi-stability, millenia or never for complete stability
A total guess by someone who knows very little about ecology or biology. Make of it what you will, take what's useful, if anything.
There will be chaos straight away, as entire ecosystems collapse. In many ways, the brutality of the shock will make for a more rapid new equilibrium as huge numbers of species go extinct, resulting im simpler ecosystems with fewer niches.
I reason that a century or two ought to be enough for hardy, invasive weed species to cover areas that are going to be fertile, provide cover for regenerating forest, and allow big trees to take over most places that they are going to.
This is what we see in areas that man disrupts and then abandons: rapid changes for a few decades, followed by long, slow ones.
After that, you won't have giant swings in CO2 levels or other really dramatic global changes, changes will be localised and some areas will be fairly stable.
Actual 'stability', similar to what man has known since civilisation began, will take millenia though, as forests and river systems continue to change over centuries.
True stability is never reached due to inevitable perturbation and normal interspecies competition and adaptation.
Your new biosphere instantly collapses
By simply copy-pasting the items, relevant flows are not established and with the lack of the flows or an initiator, they don't start to run. The gulf stream stays off, and Europe dies off. Then other biomes collapse in a frame of months, as self-regulation tries to kick in.
In the end, the planet kickstarted extreme evolutionary pressure with the mass extinction. What little survives slowly will adapt to the remains and the resulting flora and fauna might look entirely different if given a few million years.
Q: "This results in it dumping various copies of plants, animals, as well as water and air semi-randomly onto a completely separate world."
This answer assumes your powerful entity can transfer things in a blink, without being limited by energy, mass or distance. And it has all the time of the world.
Yes, it can be done
..but you'll have to start from scratch.. there is this empty planet, it has nice temperature and proper day and night cycle, but there's nothing there yet. No oxygen, no water, no nitrates, no carbon..
Copy/Paste the moon first
Advisable for compatibility with Earth's species requirements !
Copy/Paste the top layer of Earth in one go (rocky underground + atmosphere)
Now you want to copy/paste Earth. To maintain biodiversity, that is have a healthy transfer for all species involved, you'll need to prepare your new planet to maintain life. It is empty now. Your omnipotent entity may choose to copy/paste the crust first, with oceans and land on top of it. Just put ca 25km of rocky underground and 80km of atmosphere above it as a shell around your new planet. It will contain some 50% of the biosphere already, which is in the soil.
At this point, you'll require a few thousand years of waiting time, to allow tectonic plates to stabilize, let atmospheric cycles and ocean currents settle down. Weather will need to stabilize, rivers will form. I guess your omnipotent entity is immortal as well, so a relatively small wait at this point won't be an issue ?
Copy/Paste sea life and land life in the proper order
Suppose your volcano's have dimmed, your atmosphere works, oceans flow, winds have started and clouds are ready to rain, soil is in place.. you can put your plants and animals, they will survive.
Mind the proper order, you can't put everything at once, the food pyramid has to be built bottom-up.. first you'll need plant life, to maintain oxygen level.
- algae, grass
- fish and insects
- plants and trees
- other animals
Steps 1 and 2 will need some time. Steps 3, 4 and 5 can be done a few weeks before the tourists arrive.