Multiple Choice
The continuing addition of large amounts of nitrogen and phosphorus to aquatic ecosystems may exceed planetary boundaries and create a "tipping point" in which
A) nitrogen and phosphorus are depleted from soils.
B) high nitrogen and phosphorus levels cause ecosystems to change in ways difficult to reverse and that are damaging to human food production.
C) these ecosystems produce far more human food than ever before.
D) water is lost from these systems and they become deserts.
Correct Answer:

Verified
Correct Answer:
Verified
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