Benthic substrate sampling frame, Bull Trout Lake, Idaho
A scientist with SCUBA equipment holds a quadrant used to measure the relative cover of benthic plants (macrophytes) and sediments in Bull Trout Lake, Idaho. An underwater writing tablet floats on the surface to the right.
In this lake, macrophytes are abundant at depths of 3-6 m.
Photo: July 2008
"Limnology", the study of inland waters