FOSS gamedev and creative worlds

I have a world that was generated using Minetest v0.4.12. However, in v0.4.13 I notice some really neat biomes have been added from savannah to glaciers. Is there a way for me to "regenerate" my world or parts of it so that these new things can be found without losing all my builds and such? I have also added an ore with my own mod, so that would be a problem too as it is important to have available. Another thing is that I am planning on installing the sea life mod, which would need things to be generated too.

If needed I can just start fresh in another world after exporting my builds to worldedit schematics, but I'd rather make use of the one I have already been running for months. I also would assume that I can just go far enough away from my current location to a place where the world hasn't fully generated, but that is pretty inconvenient.

Thanks.

You can regenerate world to it's fresh state.but it would delete any builds or changes you have made.
Newly generated world will of course have the new biomes.

Be sure to make backup before any experiments!
You can do /deleteblocks "somearea" to delete blocks, they will regenerate iirc, if you can avoid damaging your builds.
OR
maybe this can help: https://github.com/AndrejIT/map_unexplore
IIRC this script removes any blocks except player placed, and after you do it, just use it again and should generate blocks.