Question

which human activity is responsible for overloading the nitrogen and phosphorus cycles?

Answer 1

Answere : Use and runoff of fertilizer from agricultural areas is responsible for overloading the nitrogen and phosphorus cycles.

Overloading the nitrogen and phosphorus cycles damages aquatic ecosystems. In farm fields, gardens, and suburban lawns, ammonia, nitrate, and phosphate are supplied by chemical fertilizers to stimulate plant growth
Water dissolves and carries away large quantities of these fertilizers that then drain into lakes and rivers and overstimulate the growth of phytoplankton.

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