Repeated observation or sampling at a site, on a scheduled or event basis, for study and analysis. In general, this category excludes sampling programs in which materials are obtained in the field and brought back to a laboratory for study and analysis.
Previous analysis showed this area to have reduced macroinvertebrate biodiversity, an important measure of ecosystem health. New observations indicate that conditions have improved; report includes methods and results of sampling.
Document on the federally supported interagency National Acid Precipitation Assessment Program (NAPAP) covering research on causes and effects of acid precipitation with the USGS as the lead agency for monitoring wet acid deposition.
The study of petroleum in both the saturated and unsaturated zones, to better understand the processes that control contaminant behavior, and to use this understanding to estimate the future behavior of the contaminants.
Summary of the USGS benchmark glacier program to intensively monitor climate, glacier motion, glacier mass balance, glacier geometry, and stream runoff at three glacier basins, Gulkana and Wolverine in Alaska and South Cascade in Washington.
A web-enabled database that provides for the capture, curation, integration, and delivery of bioassessment data collected by USGS, principally macroinvertebrate, algae, fish, and supporting habitat data from rivers and streams.