Question

water pollution effects on aquatic life
cultural eutrophication causes
algae blooms that need a lot of
oxygen. what is the result of this
in aquatic ecosystems?
reduced dissolved oxygen
extra dissolved carbon dioxide

Explanation:

Cultural eutrophication leads to algae blooms. Algae blooms consume large amounts of oxygen during processes like decomposition (after the algae die). In aquatic ecosystems, this high oxygen demand from algae blooms (and subsequent decomposition) reduces the amount of dissolved oxygen available for other aquatic organisms. Extra dissolved carbon dioxide is not the direct result of algae blooms' oxygen demand; the key impact here is on dissolved oxygen levels.

Answer:

Reduced dissolved oxygen