Non specific, likely means airial target. I would say airbases are land target.
I'm much more tempted to interpret it as "nodes of aerial systems".
Considering the PLA does systems destruction warfare, I wouldn't be surprised if this is just an unnecessarily technical way of describing nodes of different domain systems (land, air, sea etc), rather than actual targets in the air flying.
It's not a super intuitive way of describing it, as one would think that describing it as "enemy surface targets" would be better, but from a systems confrontation point of view I can see how it makes sense.
The alternative idea of having a primary surface to surface missile system also have a surface to air role (which it would be rather poorly optimized for, even though it technically could be done), just seems like a less likely interpretation and raises more eyebrows.