Follow the steps to stop the facebook notifications in email:
First Login to your Facebook account
1.Go to the Settings from the right upper corner drop down menu.
2. Click on Notifications on the left side as shown.
3. Click on Edit on the far right side.
4. Choose the options for notifications as per your needs.
But if you want to specifically stop a notification, then go to your email and click unsubscribe link on the bottom most of the email.
For any query, please comment!