Until October 2019, notification emails sent to region admins were automatic if you had 'add or edit' permissions in a region. As a regional admin, you didn't have much control over the notifications you were sent. At the time, there was only a profile setting in place to disable these admin emails site-wide.
We've now switched the admin notification system to use the email subscription system within Trailforks that already exists. Within this system, a user can subscribe for updates on a region or a particular trail. When you're assigned to a region as an admin, you're granted certain permissions, and your account is automatically subscribed to that region. For example, if you have editing permissions, you are subscribed to make edits in that region. Additionally, you will be subscribed to a special new "admin" subscription option. This option will send email notifications for items requiring admin approval, such as pending new content. pending edits, abuse reports, or trail reports that require approval.
Since admin notifications are now using the subscription system, as a regional admin, you now have the control to remove and edit your subscriptions to regions. You can also make your subscriptions more granular. If you are an admin for a large region, like a state, you can remove your subscription from the entire state, and instead manually subscribe to only the sub regions you wish to receive notifications for.
Adding a user to a group that already has permissions in a region will automatically subscribe that user to the regions that the group has permissions for. When another administrator or a trail association adds your permissions, they have the option to un-select "subscribe to emails." Doing this will ensure that you are NOT subscribed to a region.