If artificial eutrophication continues, what do you think will eventually happen to an ecosystem of water?

Ecosystem will be negatively impacted.

Explanation:

Eutrophication is the process in which the amount of nutrients in a water body increase due to the run off from the nearby agricultural land.  

Due to the enhancement of nutrient content of water, the productivity of water plants increases and they increase in number rapidly thereby covering the surface of the water body. This restricts the dissolution of oxygen in water from atmosphere and also causes depletion of existing dissolved oxygen. In absence of sufficient oxygen the water animals start dying.

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