What effect can fertilizer runoff have on an aquatic ecosystem?

Fertilizer runoff has a negative impact on water supplies by an increased of plant growth leading to a decrease in fish populations. Excess algae growth results in oxygen depletion which leads to an increase in the amount of nitrate-nitrogen in drinking water and a decrease in fish populations.

Explanation:

Problems. Aquatic ecosystems with decaying algae do not have enough oxygen for many life forms. As excess fertilizers enter aquatic ecosystems and cause algal blooms, the algae die off more rapidly. As algae decompose, they remove oxygen from the water, according to the Natural Resources Defense Council and the EPA.

Explanation:

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