Wow the Spain is even more strange. It was over farmed and plowed so much that soil is degraded to become like concrete and barren because the water doesn't soak in.

https://www.youtube.com/watch?v=ZUzZk_uqSWc&t=107s

For that type of devastation, I recall reading years ago that growing rye and then rolling it instead of plowing it and replanting rye again for multiple seasons can create moisture retaining top soil. They would also need to add ditches to have pools of water for wild life to make a come back.

It is a completely different phenomenon. In 500 years all these lands are going to have an ecosystem again even if they don't do anything but they have to live with it for 100s of years if they don't do anything.