Problem
Construct a two-box model for a lake that consists of an epilimnion (a wellstirred upper region) and a hypolimnion (the cold portion of the lake). rp is the rate of removal (precipitation, sedimentation), rb is the rate of burial, rd is the rate of addition to hypolimnion by dissolution, Qexc is the rate of exchange of water between epilimnion and hypolimnion. Write a mass balance equation for the steady-state concentration of a pollutant in the hypolimnion. Note that at steady state rb = rp - rd. Consider a lake where the average river water flow is 100 m3/s, an average rainfall deposition of 20 m3/s, and a mean burial rate of 200 mg/s for phosphorus. If the influent to the lake has a P loading of 5μg/L from agricultural pesticide runoff into the river, is the lake prone to eutrophication (i.e., biological productivity)? Mean P concentration for biological productivity in lakes is 5μg/L.
The response should include a reference list. Double-space, using Times New Roman 12 pnt font, one-inch margins, and APA style of writing and citations.