Preventing top level album creation??

I''ve just installed and have been playing with the Gallery. I'm wanting to create a top level of albums that normal users can't add to. I would like them instead to submit thier albums under one of the top level albums.

Not sure if I'm make sence. Also don't know if there is away to accomplish this.

I know that once an album (on the top level) is created, I can prevent users from adding further albums under it. I'm wanting to limit the number of top level albums.

Thanks,
Bob