Skip to main content
USGS - science for a changing world
Advanced Search

Filters: Tags: estuaries (X)

1,627 results (15ms)   

Date Range
Tag Types
Tag Schemes
View Results as: JSON ATOM CSV
Long-term studies were used to examine (1) contrasting time scales and mechanisms of structural variations within two benthic communities and (2) the usefulness of long data sets for evaluating human impact. A 10-year study of a San Francisco Bay mudflat, the details of which are reported elsewhere, has revealed large short-term (on the order of months) variations in species abundances within a community composed predominantly of opportunistic species. The study site, located in a highly urbanized estuary, is subject to the influence of a nearby sewage-treatment facility. However, rapid changes in population size of the common species, in part due to periodic natural habitat disturbance, impedes the detection of...
Categories: Publication; Types: Citation; Tags: Estuaries
Coastal Condition (Combined) This layer is one of the South Atlantic LCC indicators in the estuarine ecosystem (both estuarine marsh and estuarine open water). It is an index of coastal condition capturing water quality, sediment quality, and benthic community condition. Reason for Selection This index measures the overall abiotic condition of the system, is well monitored, and is synthesized by the Environmental Protection Agency (EPA) every 5 years. It integrates measures of water quality, sediment quality, and benthic habitat quality. Input Data The EPA Coastal Condition Index (CCI) is a ranking derived from a water quality index, sediment quality index, benthic index, coastal habitat index, and fish tissue...
The chemical reactivity of uranium was investigated across estuarine gradients from two of the world's largest river systems: the Amazon and Mississippi. Concentrations of dissolved (<0.45 ??m) uranium (U) were measured in surface waters of the Amazon shelf during rising (March 1990), flood (June 1990) and low (November 1991) discharge regimes. The dissolved U content was also examined in surface waters collected across estuarine gradients of the Mississippi outflow region during April 1992, August 1993, and November (1993). All water samples were analyzed for U by isotope dilution inductively coupled plasma mass spectrometry (ICP-MS). In Amazon shelf surface waters uranium increased nonconservatively from about...
Categories: Publication; Types: Citation; Tags: Estuaries
Observations of the Mobile Bay, Alabama, plume during a flood event in April 1991 reveal significant differences in the current field on either side of a front associated with the buoyant plume. During a strong southeasterly wind, turbid, low salinity water from Mobile Bay was pushed through an opening in the west side of the ebb-tidal delta and moved parallel to the coast. A stable front developed between the low salinity water of the buoyant plume (11‰) and the high salinity coastal water (>23‰) that was being forced landward by the prevailing winds. Despite the shallow water depth of 6 m, measurements of currents, temperature, and salinity show large shears and density gradients in both the vertical and the horizontal...
Categories: Publication; Types: Citation; Tags: Estuaries

map background search result map search result map Indicator V 2.0: Estuarine Combined: Coastal Condition Indicator V 2.0: Estuarine Combined: Coastal Condition