Researchers in alaska were interested in increasing the sockeye salmon (oncorhynchus nerka) population in three coastal lakes. to accomplish this, the ponds were treated with fertilizers. as a result, zooplankton biomass increased between 40% and 700% in the three lakes. the substantial growth in zooplankton would suggest that prior to these experiments, these lakes were

going under eutrophication process.

Explanation:

Body waters like lakes normally produces or receives some organic wastes, from the same living things of the environment or by pollution. In this example  the fertilizers that were dropped into the lake, they have a lot of nitrogen, carbon or phosphorous compounds, that by the passing of the time will be consumed by the living things and elevate the production of zooplankton. with the increase of zooplankton, the population of fish is expected to increase also.