Collecting pieces or specimens or making measurements or observations at determined intervals or areas. Results may be used as representative of the whole research area or population.
Water District homepage with links to detailed real-time and long-term water resources data for Missouri on streamflow, ground and surface water, and water quality.
Description of river input monitoring project's collecting and analyzing water-quality data to calculate and explain load and trend estimates of selected nutrients and suspended solids for five major river basins in the Chesapeake Bay watershed.
Overview of a project in Virginia to develop a program for assessing public supply source waters to determine their susceptibility to contamination and to determine which systems need detailed source-water assessments.
Homepage for USGS water quality information. The NWISWeb discrete sample database is a compilation of over 3.5 million historical water quality analyses in the USGS district databases. Also includes access to real-time data and a tutorial.
Links to major databases on USGS real-time and historic time period data for water quality, atmospheric deposition, streamflow, and suspended sediments and links to related databases of other agencies.
Links to research at the field stations of the Western Ecological Research Center with direct links to web pages for wildlife videos, satellite telemetry, fire ecology, invasive species, herpetology field guide, and coastal ecosystems.