Thank you for reaching out, I'm happy to help.
There is a way to turn those notifications off using notification rules. Just go to Setup -> Notifications -> Notification Rules. Or, alternatively just go here.
To stop reservation emails from being sent you will probably want to disable the Default Reservation Assignee Notifications. You can also create custom notification rules if you would only want to be notified when certain events take place.
Let us know if you need any further assistance with this.