Suction dredging in the national forests : dredging responsibly to protect river ecosystems.

"September 1997"--P. [3] of cover.

Proceedings : Symposium on Sustainable Management of Hemlock Ecosystems in Eastern North America, June 22-24, 1999, Durham, New Hampshire /

Includes bibliographical references.

Dynamic behavior of vinyl chloride in aquatic ecosystems /

Prepared for Environmental Research Laboratory, Office of Research and Development, U. S. Environmental Protection Agency, Athens Georgia.

Organochlorine pesticides and PCBs in aquatic ecosystems of the Central Columbia Plateau.

Mode of access: Internet.

Effects of fire on Madrean Province ecosystems : a symposium proceedings /

"December 1996."