Delaware River estuary

Schwartz M, Sharpe J. (2003) Use of Rn to trace groundwater discharge into the Delaware River. Estuaries in press... 

Figure 7.25 The

Riedel GF, Sanders JG. 1998. Trace element speciation and behavior in the tidal Delaware River. Estuaries 21(l) 78-90. 

Cottrell, M. T., and Kirchman, D. L. (2004). Single-cell analysis of bacterial growth, cell size, and community structure in the Delaware River estuary. Aquat. Microb. Ecol. 34, 139—149. 

Lipschultz et al. (1985) documented the light inhibition of NH3 oxidation in the Delaware River and concluded that this effect influenced the spatial distribution of nitrification in the estuary. Depending on their depth, light is not usually a problem for nitrification in sediments. In shallow sediments, light may have an indirect positive effect on nitrification rates by increasing photosynthesis, and thus increasing oxygen supply to the sediments (Lorenzen et al., 1998). 

Fig. 2. Variations in surface microlayer chemical composition as shown by DEI-MS spectra for three microlayers (SepPak eluates) collected along a cruise track from Delaware Bay south-eastward across the continental shelf. Spectral intensities are normalised to the most abundant m/z intensity. The spectrum of the sample in the upper panel, which was collected within the Delaware River plume, is dominated by the presence of humic compounds that characteristically pyrolyse to produce mass fragments at every m/z value. The contribution from humic materials decreases markedly with distance from the estuary...

Cerco, C.F., and Seitzinger, S.P. (1997) Measured and modeled effects of benthic algae on eutrophication in Indian River-Rehoboth Bay, Delaware. Estuaries 20, 231-248. 

Largely as the result of such studies, the 1990 Clean Air Act Amendments contain specific provisions (Section 112m, the so-called "Great Waters section) which legislatively mandate an examination of atmospheric contaminant deposition to coastal and inland waters. This includes smaller east coast estuaries such as Delaware s Inland Bays (Rehoboth and Indian River) since their combined output to local shelf waters can be equivalent. With this in mind, the primary objective of this study was to accurately assess the relative atmospheric and fluvial loading of trace elements to the Inland Bays. 

The Delaware Inland Bays are comprised of three interconnected estuaries Rehoboth Bay, Indian River Bay and Little Assawoman Bay, located on the mid-Atlantic coast of Delaware (Figure 1). Although dwarfed in size by large east coast estuaries such as the Chesapeake and Delaware Bays, the Delaware Inland Bays are more typical of the numerous small, shallow, poorly-flushed systems that are found along the Atlantic and Gulf coasts. 

The U.S. ERA currently supports and maintains the WASP model, including various versions from 4 through 7 (Ambrose et al., 1988 1993 Wool et al., 2001). The first ERA public domain WASP applications to examine toxic chemicals in receiving waters and sediments date back to late 1980s with evaluations of volatile organics in the Delaware Estuary (Ambrose, 1987) and heavy metals in the Deep River, North Carolina (JRB, 1984). As a public domain model, various enhancements of the WASP model have been made over the years in order to address site-specific needs and improve on the standard transport and kinetic formulations to simulate a variety of toxics, especially hydrophobic organic chemicals (HOCs) and metals. Several modified versions of the WASP model incorporate settling and resuspension functions that are not available in the EPA-supported model. The WASP model discussion... 

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