Does flooding affect an ocean environment in any way? How?

What is an environment? An ocean is not an environment, it is a LOT of environments. The Amazon River carries drinkable water forty miles into the Atlantic ocean. Is that a river environment, or an ocean environment? The Pacific ocean covers half the Earth. People in Borneo would not even be aware of a flood in California, but surprisingly, a landslide in Chile causes tsunamis in Japan. So what exactly do you mean by "environment?

A flood refers to a particular river overflowing it's banks. One effects is a large volume of mud consisting of very fine silt. The flooded land gets fresh fertilizer, the fish in the river get a bonanza of food churned up, small fish get protection by hiding in the silty water, and the ocean may or may not be measurably affected. The most common effect that a river has on an ocean is by providing sand for the beaches. A flood might or might not interrupt that supply.

BTW, an ocean does not have to be a very big ocean. There is an ocean in Russia that dried up because they stopped all the rivers feeding it.
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