What might happen to the fisheries if upwelling stopped

If upwelling stopped then the food chain would break thus causing the fisheries to collapse

Destruction of fish habitats

Explanation:

As up-welling is the phenomenon that involves the wind movement of the waves and that drives the nutrient-rich waters towards the surface. And this forms a great place for the breeding of the fishing population and hence this water is essential for the growth and the reproduction of the primary producers and as a fact, about 25 % of the fish caught in the world comes from the marine fresh warm waters.

Brand c i think that should be it