Hmm I do not know of a thread that explains them all but I'll try and help. At the top banner there's a help tab. Click that and go to trophies. It gives a break down of points and list all the badges. It used to have explanations but was lost in the site upgrade.
I can tell you most of them are given out by mods or admins and comes from you just being active and a positive force in the community. Like see the little dancing man bear pig. That's the AFN vibe badge.
All of the others you can earn directly are seed company supporter badges. That's when you grow a strain from start to finish of a breeder that is a AFN sponsor. Then when completed just do a smoke review.
On the last post of your completed thread you'll see a report post button on the thread box. Just push that and ask for your seed supporter badge.
The others you see under my name are plant of the month or BOM trophy from winning the monthly comp.