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.
Explains sources of mercury in the air, ways in which mercury is concentrated in animals, and describes how we measure deposition of atmospheric mercury, with summaries of observations.
Even though lead usage has declined due to environmental awareness and regulation, several human sources of lead continue to affect birds. Hunting ammunition and fishing gear are ingested by the birds, with toxic effects.
Macroinvertebrate data collected by USGS or USFS from 73 sites from 2000 to 2007 and algal data collected from up to 26 sites between 2000 and 2001 in the Eagle River watershed, with emphasis on methods of sample collection and data processing.
Regional studies mapping the seafloor sedimentary character and assessing marine sand and gravel resources around the United States, to inform beach nourishment and coastal restoration, benthic habitat and sediment transport studies
Research findings and examples of application to real problems--highly variable conditions cause the production of toxic methyl mercury in the environment which accumulates in fish.
Description of studies conducted to evaluate the surface water, ground water, water interactions, and water quality of Methow River Basin in Washington. With links to related science topics, datasets, maps, project summaries, and news.
Plan for an upcoming study, at the microbiological scale, of the benthic communities (including corals) that reside in and around mid-Atlantic canyons, which are located at the edge of the continental shelf.
Homepage for the research on occurrence, movement, flux, fate, and effects of agricultural chemicals, such as pesticides, in 25 states by the Midcontinent Agricultural Chemical Research Project (MACRP) with links to study results and publications.