Annotations are not themselves AOP, they just decorate a class, property or method with metadata. In AOP terms, you could say annotations describe "Aspects", but by themselves they do not provide any extra functionality.
AOP usually requires information to determine where to inject or provide interception. Some AOP libraries use XML to describe the places of the program in which to weave their functionality, others use annotations for this same purpose.
So, Annotations are not AOP, but rather a way of marking locations in the code where AOP can intervene and add cross-cutting concerns.