Yes, you can. Whether to receive an email alert when a reply is submitted to a conversation or comment that you started is a Preference setting that can be toggled on or off globally for all of your conversations and comments. 

By default this setting is toggled on, so that you will receive email alerts to all replies to your conversations and comments. To toggle it off for all conversations and comments, do the following:

• Click on the "Preferences" link in the upper right hand corner of the Hub (you must be logged-in to the Hub)
• Scroll down to the "Additional Settings" section, and look for the item "Yes, want email notifications when someone replies".
• Ensure it is checked if you want email notifications, or that it is not checked if you do not.
• Click the "Save Settings" button if you made a change that you want to keep.

Regardless of what your global preference is on this account for email alerts, you can turn the email alert feature on or off on each conversation or comment that you post to the Hub.

When you are creating a conversation or comment,

• scroll down to "Advanced Options" section
• click on the circle with the double down arrows to the left of the "Advanced Options" term. This will pop open a box of options.
  
• Find the item "Alert me by email when replies occur"
• toggle it on or off depending on whether you want to receive email alerts or not respectively.