Is china's production of seafood a ouitive or a negative for louisiana's seafood production

At best it doesn't matter. If there are enough fish to go around in both locations, then the two areas can coexist.

If however, the two jurisdictions are going  to be in competition with each other, then that's not good.

China's Output: 32.5 million tons = 32,500,000,000 pounds 32.5 billion pounds in 2004

Louisiana produced 1.2 billion pounds of sea food in 2005

Louisiana's output compared to China is quite small. I would guess most of it is for domestic use. It means that every man woman and child in the United States eats 3.64 pounds of fish a year. There won't be much left over for export. This does not take cat food into consideration. I cannot find exact statistics on sea creatures (like tune or salmon) that are put in cat food particularly (since they require meat) but it's going to cut down on what could be exported.

I don't think China has much of an effect on what happens in Louisiana.