Accession Number : ADA314372

Title :   Investigations of the Production, Transport, and Survival of Monoecious Hydrilla Propagules in the Tidal Potomac River.

Descriptive Note : Final rept.,

Corporate Author : ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS ENVIRONMENTAL LAB

Personal Author(s) : McFarland, Dwilette G. ; Barko, John W.

PDF Url : ADA314372

Report Date : AUG 1996

Pagination or Media Count : 43

Abstract : The submersed aquatic vegetation (SAV) of the freshwater tidal Potomac River has a history of dramatic change in abundance and distribution. Following a four-decade absence in the tidal river (between Chain Bridge and Quantico, VA; Figure 1), SAV reappeared in 1983 in the upper tidal reach and, by 1986, had spread farther downstream into the lower tidal reach as well (Paschal et al. 1982; Haramis and Carter 1983; Carter, Paschal, and Bartow 1985; Carter and Rybicki 1986,1990; U.S. Geological Survey 1994, unpublished). Three submersed species, Vallisneria americana Michx., Myri- ophyllum spicatum L., and Heteranthera dubia (Jacq.) MacM., were dominant between 1983 and 1985; but by 1986, monoecious Hydrilla verticillata (L.f.) a newly established exotic species (first documented near Dyke Marsh, Virginia, in 1982; Steward et al. 1984), had become most abundant. Since 1986, SAV in portions of the tidal river has declined, with the upper tidal reach experiencing the most severe losses (U.S. Geological Survey 1994, unpublished).

Descriptors :   *RIVERS, *VEGETATION, *TIDES, POTOMAC RIVER, VIRGINIA, PRODUCTION, FRESH WATER, CHAINS, LOSSES, WETLANDS, SURVIVAL(PERSONNEL), AQUATIC ORGANISMS, BRIDGES, AQUATIC BIOLOGY, GROWTH(PHYSIOLOGY), AQUATIC PLANTS.

Subject Categories : Biology
      Hydrology, Limnology and Potamology
      Water Pollution and Control

Distribution Statement : APPROVED FOR PUBLIC RELEASE