Mounted drives and removable media are displayed both in Unity launcher and Ubuntu desktop at the same time, which is not really useful and looks cluttered. Following is what you need to do to disable mounted drives from showing up in your Ubuntu desktop.
Hit Alt+ F2 and type ‘gconf-editor’.
Gconf- Editor will open up. Browse to apps – nautilus – desktop.
Notice the highlighted ‘volumes_visible’ option. Just untick it. Done.
Mounted drives won’t be displayed in your desktop anymore.

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