There were plugins called
disableactionsbygroup (and before that another one called
closedwiki) which could be used to limit wiki actions (edit pages, see recent changes,...) for specified user groups.
disableactionsbygroup works, but it leaves the buttons visible to the user, just to display a message like "operation not allowed" after pressing it.
It would be better to hide such unusable buttons conditionally.
To remove them from templates is not an option (I think), as button availability is user dependent.
See also:
Removing Wiki options for unregistered users (
http://forum.dokuwiki.org/post/13814) - disableactionsbygroup plugin revival!
Disable Actions by Group (
http://notes.splitbrain.org/users:phptard:disableactionsbygroup)