An experiment you have been conducting uses a large pond to observe how the input from fertilizer runoff affects the native pond community.You find that many amphibians are not able to survive in this pond when the nitrogen levels are high.What could you do next to best test if nitrogen concentrations affect amphibians?
A) Do a field experiment to exclude amphibians from the pond and see if they survive elsewhere
B) Experimentally raise frogs in a controlled laboratory experiment where some are exposed to water from the pond at certain periods of time and others only raised in filtered water for the duration of the experiment.
C) Find other ponds and input runoff to see if amphibians there cannot survive too
D) Increase the runoff input at your pond and see if amphibian survivorship decreases

Question

Quizplus · Accepted Answer

Option B is the best choice as it is a controlled laboratory experiment where the exposure of frogs to water with high nitrogen concentration can be compared to filtered water. This would help establish a cause-and-effect relationship between nitrogen levels and the survival of amphibians. Option A does not test the effect of nitrogen concentration, while options C and D are not appropriate as they do not control for other factors that may affect survival.

An Experiment You Have Been Conducting Uses a Large Pond