What does “land poverty” mean?

It means a lack of sufficient access to or ownership of land.

It does not mean that the land itself is poor-quality land.

This distinction is important.

“Land poverty” means:

poverty in terms of land ownership or access to land.

For example:

A formerly enslaved person has freedom but no farm.

He must therefore obtain access to land from someone who owns it.

That creates economic dependence.