Hahaha!  Have you never seen anyone fishing?   They fish EVERYWHERE, even in the little man made lakes in parks.   No you don't need a license,  even if its in the law somewhere no one will come and stop you.  Man the Chinese take home and eat what they catch.

Fishing is one of my favorite hobbies. Iv fished in countless lakes and rivers. Never been asked for any kind of license, nor have I ever heard of a "fishing license" here. However, in Hong Kong you do need a license.

Yes you sure do. If you didn't need one all the lakes and rivers and anything with fish in it would be completely wiped out! 

You need balls of steel or a death wish to eat them.

Yes you do. You need a mining permit because of the amount of heavy metals you will obtain if you catch one.

I saw lot of people fishing, sure without permit, on every dirty river. On the other hand, those who are making they living from fishing, living on the boats and so on, they need permit which cost 3000rmb per year, according to Greenpeace article I have read about 1 month ago. In the heavy polluted rivers they sometimes can not catch any fish for few days, and they drinking this water ... 

i think u neeed to wear a mask when u get around a river it is toxic

Without exception, each and every river in this country is a turbid ditch of toxic waste.  Be warned: stay away from the rivers. if you really want to go fishing, fish but throw the damn critter back into the feculent slime.  Never eat river fish here.  Better bet: mutton from Shanghai...

you might need your stomach pumped afterwards.