What is Study-Unit Investigation?
Study-Unit Investigation meaning The systematic study of a NAWQA Study Unit. These investigations consist of four main components: Retrospective Analysis, Occurrence and Distribution and Trend and Change Assessments, and Case Studies. Study Units are organized into three groups of 20 that are studied on a rotational schedule, with 3-year intensive study periods repeated once every 9 years.
reference: USGS – GLOSSARY OF STUDY COMPONENTSWhat is