Final answer:
A hydrologist would measure the discharge of a body of water to determine if the flow has changed significantly.
Step-by-step explanation:
A hydrologist would measure the discharge of a body of water to determine if the flow has changed significantly.
Discharge refers to the volume of water flowing through a river channel over time. By measuring the discharge, hydrologists can assess if there has been a significant increase or decrease in the flow of water, which can indicate changes in precipitation patterns, vegetation, topography, land use, and soil characteristics.
The other options listed in the question, such as the stand, stage, and stage-discharge relationship, are not direct measurements used to determine significant changes in water flow.