[drabadur]

The problem of Spain is intense anthropogenic land (mis-)use including deforestation and mining, which led to the desertification especially in the south in the first place; this has been happening since pre-historic times. So, no, there shouldn't be deserts in Spain right now, and they are for the most part not natural. Read further here: https://www.sciencedirect.com/science/article/abs/pii/S00346... (free version available via google search on ResearchGate)

[aregue]

Exactly. Los Monegros was until 1766 Europes largest oak (encina) forest. It had been a communal forest. The forest was privatized and cut to cultivate cereal.

[toomuchtodo]

Does Spain have any reforestation efforts planned for areas experiencing anthropogenic desertification?

[pvaldes]

Without the will to jail arsonists first is a waste of money.

[MichaelZuo]

Huh, it makes me wonder how the Black Forest in Germany was preserved.

[Amezarak]

It mostly wasn’t. What you see now is a tiny remnant.

[willdough]

The linked article is about deforestation by humans and is irrelevant to the fact that huge parts of Spain have long been deserts.

[drabadur]

Deforestation is the only major relevant factor that led to the formation of any desert in Spain, and this started a "long" time ago, and is purely and simply controlled by humans. For example, the famous Tabernas desert is the result of deforestation, followed by intensive erosion.