Dissolved Nitrogen in Estuarine Waters

During the last twenty years, water column concentrations of dissolved N were probably the most intensively measured feature of N in estuarine environments. For example, about 8000 measurements of each of the common dissolved N species (i.e., NO2, NO3, NF44 and dissolved organic nitrogen) were made per year for the 

We re-visited the issue of water column N distributions to see if we could find distinctive seasonal patterns related to estuarine type, location within an estuary and climate variability (i.e., wet, dry, average inflow conditions). We obtained ammonium (referred to hereafter as NH4), nitrite (NO2), nitrate (NO3), and phosphate (PO4) concentration data from 44 USA estuarine systems. Several locations (e.g., tidal freshwater, oHgohahne, mesohahne, polyhahne) were selected in some systems and in a dozen cases we also obtained concentration data during dry, average and wet years (Frank et al., 2007). 

Strong seasonal patterns were evident for NO2 + NO3 and PO4 concentrations (Fig. 18.3). Nitrite -f nitrate concentrations were highest during winter if winter and 

Patuxent River, tidal fresh 70 29 41 PO This study 

Entries labeled this study are from the Chesapeake Bay Water Quality Monitoring Program (2004). Measurement methods included PO, persulfate oxidation UV, ultraviolet oxidation NG, not given. 

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