The map below shows status and trends at four stations in the Lower Patuxent River for ammonium (NH4+) and phosphorus (PO4-3) fluxes (observed data).

Ammonium (NH4+)

The current status (average of 1996-1998 data) of ammonium fluxes at the four SONE stations in the Patuxent River is illustrated above.  Ideally, we want to see low NH4+ fluxes. With low NH4+, very little nutrients are available for phytoplankton to use to increase their numbers and biomass. Among the four SONE stations in the Patuxent River, two had NH4+ fluxes in the fair range, and two were in the poor range. It should be noted that high river flow years, such as 1996, have a strong influence on ammonium fluxes (fluxes increase). Understanding this, the opposite could be true as well; low river flow years, such as 1999, could decrease ammonium fluxes. Ammonium is part of the nitrification process that helps restore estuarine systems.

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legend "Good” areas are not necessarily of the quality needed by living resources.
*Status is relative to other similar areas in the Bay.
**Trends are significant at p < 0.01.

For more information, please contact Renee Karrh at (410) 260-8628.

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